Merge pull request 'feat(storage): add revision number to documents' (#24) from document-revision into master

Reviewed-on: #24

.env.dist

@@ -1,4 +1,4 @@
 RUN_APP_ARGS=""
 #EDGE_DOCUMENTSTORE_DSN="rpc://localhost:3001/documentstore?tenant=local&appId=%APPID%"
-#EDGE_BLOBSTORE_DSN="cache://localhost:3001/blobstore?driver=rpc&tenant=local&appId=%APPID%"
+#EDGE_BLOBSTORE_DSN="cache://localhost:3001/blobstore?driver=rpc&tenant=local&appId=%APPID%&blobCacheStoreType=fs&blobCacheStoreBaseDir=data/cache/%APPID%&blobCacheSize=64MB"
 #EDGE_SHARESTORE_DSN="rpc://localhost:3001/sharestore?tenant=local"

.gitignore

@@ -2,7 +2,7 @@
 /bin
 /.env
 /tools
-*.sqlite
+*.sqlite*
 /.gitea-release
 /.edge
 /data

.goreleaser.yml

@@ -108,10 +108,17 @@ nfpms:
         file_info:
           mode: 0640
         packager: apk
+      - src: misc/packaging/openrc/storage-server.logrotate.conf
+        dst: /etc/logrotate.d/storage-server
+        packager: apk
       - dst: /var/lib/storage-server
         type: dir
         file_info:
           mode: 0700
         packager: apk
+      - dst: /var/log/storage-server
+        type: dir
+        file_info:
+          mode: 0700
     scripts:
       postinstall: "misc/packaging/common/postinstall-storage-server.sh"

cmd/blobstore-test/main.go

@@ -0,0 +1,146 @@
+package main
+
+import (
+	"context"
+	"crypto/rand"
+	"flag"
+	"io"
+	mrand "math/rand"
+	"runtime"
+	"time"
+
+	"forge.cadoles.com/arcad/edge/pkg/storage"
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver"
+	"github.com/pkg/errors"
+	"gitlab.com/wpetit/goweb/logger"
+
+	_ "forge.cadoles.com/arcad/edge/pkg/storage/driver/cache"
+	_ "forge.cadoles.com/arcad/edge/pkg/storage/driver/rpc"
+	_ "forge.cadoles.com/arcad/edge/pkg/storage/driver/sqlite"
+)
+
+var (
+	dsn string
+)
+
+func init() {
+	flag.StringVar(&dsn, "dsn", "cache://./test-cache.sqlite?driver=sqlite&_pragma=foreign_keys(1)&_pragma=journal_mode=wal&bigCacheShards=32&bigCacheHardMaxCacheSize=128&bigCacheMaxEntrySize=125&bigCacheMaxEntriesInWindow=200000", "blobstore dsn")
+}
+
+func main() {
+	flag.Parse()
+
+	ctx := context.Background()
+
+	logger.SetLevel(logger.LevelDebug)
+
+	blobStore, err := driver.NewBlobStore(dsn)
+	if err != nil {
+		logger.Fatal(ctx, "could not create blobstore", logger.CapturedE(errors.WithStack(err)))
+	}
+
+	bucket, err := blobStore.OpenBucket(ctx, "default")
+	if err != nil {
+		logger.Fatal(ctx, "could not open bucket", logger.CapturedE(errors.WithStack(err)))
+	}
+
+	defer func() {
+		if err := bucket.Close(); err != nil {
+			logger.Fatal(ctx, "could not close bucket", logger.CapturedE(errors.WithStack(err)))
+		}
+	}()
+
+	go readRandomBlobs(ctx, bucket)
+
+	for {
+		writeRandomBlob(ctx, bucket)
+
+		time.Sleep(1 * time.Second)
+
+		size, err := bucket.Size(ctx)
+		if err != nil {
+			logger.Fatal(ctx, "could not retrieve bucket size", logger.CapturedE(errors.WithStack(err)))
+		}
+
+		logger.Debug(ctx, "bucket stats", logger.F("size", size))
+	}
+}
+
+func readRandomBlobs(ctx context.Context, bucket storage.BlobBucket) {
+	for {
+		infos, err := bucket.List(ctx)
+		if err != nil {
+			logger.Fatal(ctx, "could not list blobs", logger.CapturedE(errors.WithStack(err)))
+		}
+
+		total := len(infos)
+		if total == 0 {
+			logger.Debug(ctx, "no blob yet")
+
+			continue
+		}
+
+		blob := infos[mrand.Intn(total)]
+
+		readBlob(ctx, bucket, blob.ID())
+
+		time.Sleep(250 * time.Millisecond)
+	}
+}
+
+func readBlob(ctx context.Context, bucket storage.BlobBucket, blobID storage.BlobID) {
+	ctx = logger.With(ctx, logger.F("blobID", blobID))
+
+	reader, err := bucket.NewReader(ctx, blobID)
+	if err != nil {
+		logger.Fatal(ctx, "could not create reader", logger.CapturedE(errors.WithStack(err)))
+	}
+
+	defer func() {
+		if err := reader.Close(); err != nil {
+			logger.Fatal(ctx, "could not close reader", logger.CapturedE(errors.WithStack(err)))
+		}
+	}()
+
+	if _, err := io.ReadAll(reader); err != nil {
+		logger.Fatal(ctx, "could not read blob", logger.CapturedE(errors.WithStack(err)))
+	}
+}
+
+func writeRandomBlob(ctx context.Context, bucket storage.BlobBucket) {
+	blobID := storage.NewBlobID()
+	buff := make([]byte, 10*1024)
+
+	writer, err := bucket.NewWriter(ctx, blobID)
+	if err != nil {
+		logger.Fatal(ctx, "could not create writer", logger.CapturedE(errors.WithStack(err)))
+	}
+
+	defer func() {
+		if err := writer.Close(); err != nil {
+			logger.Fatal(ctx, "could not close writer", logger.CapturedE(errors.WithStack(err)))
+		}
+	}()
+
+	if _, err := rand.Read(buff); err != nil {
+		logger.Fatal(ctx, "could not read random data", logger.CapturedE(errors.WithStack(err)))
+	}
+
+	if _, err := writer.Write(buff); err != nil {
+		logger.Fatal(ctx, "could not write blob", logger.CapturedE(errors.WithStack(err)))
+	}
+
+	printMemUsage(ctx)
+}
+
+func printMemUsage(ctx context.Context) {
+	var m runtime.MemStats
+	runtime.ReadMemStats(&m)
+	logger.Debug(
+		ctx, "memory usage",
+		logger.F("alloc", m.Alloc/1024/1024),
+		logger.F("totalAlloc", m.TotalAlloc/1024/1024),
+		logger.F("sys", m.Sys/1024/1024),
+		logger.F("numGC", m.NumGC),
+	)
+}

go.mod

@@ -3,14 +3,15 @@ module forge.cadoles.com/arcad/edge
 go 1.21
 
 require (
-	github.com/allegro/bigcache/v3 v3.1.0
 	github.com/getsentry/sentry-go v0.25.0
 	github.com/hashicorp/golang-lru/v2 v2.0.7
 	github.com/hashicorp/mdns v1.0.5
+	github.com/inhies/go-bytesize v0.0.0-20220417184213-4913239db9cf
 	github.com/jackc/puddle/v2 v2.2.1
 	github.com/keegancsmith/rpc v1.3.0
 	github.com/klauspost/compress v1.16.6
 	github.com/lestrrat-go/jwx/v2 v2.0.8
+	github.com/mitchellh/hashstructure/v2 v2.0.2
 	github.com/ulikunitz/xz v0.5.11
 	go.uber.org/goleak v1.3.0
 	modernc.org/sqlite v1.20.4
@@ -87,3 +88,5 @@ require (
 	modernc.org/strutil v1.1.3 // indirect
 	modernc.org/token v1.0.1 // indirect
 )
+
+replace github.com/allegro/bigcache/v3 v3.1.0 => github.com/Bornholm/bigcache v0.0.0-20231201111725-1ddf51584cad

go.sum

@@ -53,8 +53,6 @@ github.com/alecthomas/kong v0.2.1-0.20190708041108-0548c6b1afae/go.mod h1:+inYUS
 github.com/alecthomas/kong-hcl v0.1.8-0.20190615233001-b21fea9723c8/go.mod h1:MRgZdU3vrFd05IQ89AxUZ0aYdF39BYoNFa324SodPCA=
 github.com/alecthomas/repr v0.0.0-20180818092828-117648cd9897 h1:p9Sln00KOTlrYkxI1zYWl1QLnEqAqEARBEYa8FQnQcY=
 github.com/alecthomas/repr v0.0.0-20180818092828-117648cd9897/go.mod h1:xTS7Pm1pD1mvyM075QCDSRqH6qRLXylzS24ZTpRiSzQ=
-github.com/allegro/bigcache/v3 v3.1.0 h1:H2Vp8VOvxcrB91o86fUSVJFqeuz8kpyyB02eH3bSzwk=
-github.com/allegro/bigcache/v3 v3.1.0/go.mod h1:aPyh7jEvrog9zAwx5N7+JUQX5dZTSGpxF1LAR4dr35I=
 github.com/barnybug/go-cast v0.0.0-20201201064555-a87ccbc26692 h1:JW4WZlqyaNWUUahfr7MigeDW6jmtam5cTzzo1lwsFhE=
 github.com/barnybug/go-cast v0.0.0-20201201064555-a87ccbc26692/go.mod h1:Au0ipPuCBA7zsOC61SnyrYetm8VT3vo1UJtwHeYke44=
 github.com/census-instrumentation/opencensus-proto v0.2.1/go.mod h1:f6KPmirojxKA12rnyqOA5BBL4O983OfeGPqjHWSTneU=
@@ -208,6 +206,8 @@ github.com/ianlancetaylor/demangle v0.0.0-20181102032728-5e5cf60278f6/go.mod h1:
 github.com/ianlancetaylor/demangle v0.0.0-20200824232613-28f6c0f3b639/go.mod h1:aSSvb/t6k1mPoxDqO4vJh6VOCGPwU4O0C2/Eqndh1Sc=
 github.com/igm/sockjs-go/v3 v3.0.2 h1:2m0k53w0DBiGozeQUIEPR6snZFmpFpYvVsGnfLPNXbE=
 github.com/igm/sockjs-go/v3 v3.0.2/go.mod h1:UqchsOjeagIBFHvd+RZpLaVRbCwGilEC08EDHsD1jYE=
+github.com/inhies/go-bytesize v0.0.0-20220417184213-4913239db9cf h1:FtEj8sfIcaaBfAKrE1Cwb61YDtYq9JxChK1c7AKce7s=
+github.com/inhies/go-bytesize v0.0.0-20220417184213-4913239db9cf/go.mod h1:yrqSXGoD/4EKfF26AOGzscPOgTTJcyAwM2rpixWT+t4=
 github.com/jackc/puddle/v2 v2.2.1 h1:RhxXJtFG022u4ibrCSMSiu5aOq1i77R3OHKNJj77OAk=
 github.com/jackc/puddle/v2 v2.2.1/go.mod h1:vriiEXHvEE654aYKXXjOvZM39qJ0q+azkZFrfEOc3H4=
 github.com/jessevdk/go-flags v1.4.0/go.mod h1:4FA24M0QyGHXBuZZK/XkWh8h0e1EYbRYJSGM75WSRxI=
@@ -258,6 +258,8 @@ github.com/miekg/dns v0.0.0-20161006100029-fc4e1e2843d8/go.mod h1:W1PPwlIAgtquWB
 github.com/miekg/dns v1.1.41/go.mod h1:p6aan82bvRIyn+zDIv9xYNUpwa73JcSh9BKwknJysuI=
 github.com/miekg/dns v1.1.53 h1:ZBkuHr5dxHtB1caEOlZTLPo7D3L3TWckgUUs/RHfDxw=
 github.com/miekg/dns v1.1.53/go.mod h1:uInx36IzPl7FYnDcMeVWxj9byh7DutNykX4G9Sj60FY=
+github.com/mitchellh/hashstructure/v2 v2.0.2 h1:vGKWl0YJqUNxE8d+h8f6NJLcCJrgbhC4NcD46KavDd4=
+github.com/mitchellh/hashstructure/v2 v2.0.2/go.mod h1:MG3aRVU/N29oo/V/IhBX8GR/zz4kQkprJgF2EVszyDE=
 github.com/mitchellh/mapstructure v1.1.2/go.mod h1:FVVH3fgwuzCH5S8UJGiWEs2h04kUh9fWfEaFds41c1Y=
 github.com/mitchellh/mapstructure v1.5.0 h1:jeMsZIYE/09sWLaz43PL7Gy6RuMjD2eJVyuac5Z2hdY=
 github.com/mitchellh/mapstructure v1.5.0/go.mod h1:bFUtVrKA4DC2yAKiSyO/QUcy7e+RRV2QTWOzhPopBRo=

misc/jenkins/Dockerfile

@@ -4,7 +4,7 @@ ARG HTTP_PROXY=
 ARG HTTPS_PROXY=
 ARG http_proxy=
 ARG https_proxy=
-ARG GO_VERSION=1.21.2
+ARG GO_VERSION=1.21.5
 
 # Install dev environment dependencies
 RUN export DEBIAN_FRONTEND=noninteractive &&\

misc/packaging/openrc/storage-server.logrotate.conf

@@ -0,0 +1,9 @@
+/var/log/storage-server/storage-server.log {
+	missingok
+	sharedscripts
+	compress
+	rotate 7
+	postrotate
+		/etc/init.d/storage-server restart
+	endscript
+}

misc/packaging/openrc/storage-server.openrc.sh

@@ -3,7 +3,7 @@
 command="/usr/bin/storage-server"
 command_args="run"
 supervisor=supervise-daemon
-output_log="/var/log/storage-server.log"
+output_log="/var/log/storage-server/storage-server.log"
 error_log="$output_log"
 
 depend() {

pkg/app/promise_proxy.go

@@ -46,11 +46,11 @@ func NewPromiseProxyFrom(rt *goja.Runtime) *PromiseProxy {
 	return NewPromiseProxy(promise, resolve, reject)
 }
 
-func IsPromise(v goja.Value) (*goja.Promise, bool) {
+func isPromise(v any) (*goja.Promise, bool) {
 	if v == nil {
 		return nil, false
 	}
 
-	promise, ok := v.Export().(*goja.Promise)
+	promise, ok := v.(*goja.Promise)
 	return promise, ok
 }

pkg/app/server.go

@@ -23,7 +23,7 @@ type Server struct {
 	modules   []ServerModule
 }
 
-func (s *Server) ExecFuncByName(ctx context.Context, funcName string, args ...interface{}) (any, error) {
+func (s *Server) ExecFuncByName(ctx context.Context, funcName string, args ...any) (any, error) {
 	ctx = logger.With(ctx, logger.F("function", funcName), logger.F("args", args))
 
 	ret, err := s.Exec(ctx, funcName, args...)
@@ -34,9 +34,9 @@ func (s *Server) ExecFuncByName(ctx context.Context, funcName string, args ...in
 	return ret, nil
 }
 
-func (s *Server) Exec(ctx context.Context, callableOrFuncname any, args ...interface{}) (any, error) {
+func (s *Server) Exec(ctx context.Context, callableOrFuncname any, args ...any) (any, error) {
 	type result struct {
-		value goja.Value
+		value any
 		err   error
 	}
 
@@ -110,7 +110,7 @@ func (s *Server) Exec(ctx context.Context, callableOrFuncname any, args ...inter
 		}
 
 		done <- result{
-			value: value,
+			value: value.Export(),
 		}
 
 		logger.Debug(ctx, "executed callable", logger.F("callable", callableOrFuncname), logger.F("duration", time.Since(start).String()))
@@ -129,20 +129,18 @@ func (s *Server) Exec(ctx context.Context, callableOrFuncname any, args ...inter
 			return nil, errors.WithStack(result.err)
 		}
 
-		value := result.value
-
-		if promise, ok := IsPromise(value); ok {
-			value = s.waitForPromise(promise)
+		if promise, ok := isPromise(result.value); ok {
+			return s.waitForPromise(promise), nil
 		}
 
-		return value.Export(), nil
+		return result.value, nil
 	}
 }
 
-func (s *Server) waitForPromise(promise *goja.Promise) goja.Value {
+func (s *Server) waitForPromise(promise *goja.Promise) any {
 	var (
 		wg    sync.WaitGroup
-		value goja.Value
+		value any
 	)
 
 	wg.Add(1)
@@ -162,7 +160,7 @@ func (s *Server) waitForPromise(promise *goja.Promise) goja.Value {
 					return
 				}
 
-				value = promise.Result()
+				value = promise.Result().Export()
 
 				breakLoop = true
 			})

pkg/module/blob/http.go

@@ -2,6 +2,7 @@ package blob
 
 import (
 	"encoding/json"
+	"io"
 	"io/fs"
 	"mime/multipart"
 	"net/http"
@@ -164,7 +165,14 @@ func handleAppDownload(w http.ResponseWriter, r *http.Request) {
 		}
 	}()
 
-	http.ServeContent(w, r, string(replyMessage.BlobInfo.ID()), replyMessage.BlobInfo.ModTime(), replyMessage.Blob)
+	// TODO Fix usage of ServeContent
+	// http.ServeContent(w, r, string(replyMessage.BlobInfo.ID()), replyMessage.BlobInfo.ModTime(), replyMessage.Blob)
+
+	w.Header().Add("Content-Type", replyMessage.BlobInfo.ContentType())
+
+	if _, err := io.Copy(w, replyMessage.Blob); err != nil {
+		logger.Error(ctx, "could not write blob", logger.CapturedE(errors.WithStack(err)))
+	}
 }
 
 type uploadedFile struct {

pkg/storage/document_store.go

@@ -9,12 +9,16 @@ import (
 	"github.com/oklog/ulid/v2"
 )
 
-var ErrDocumentNotFound = errors.New("document not found")
+var (
+	ErrDocumentNotFound         = errors.New("document not found")
+	ErrDocumentRevisionConflict = errors.New("document revision conflict")
+)
 
 type DocumentID string
 
 const (
 	DocumentAttrID        = "_id"
+	DocumentAttrRevision  = "_revision"
 	DocumentAttrCreatedAt = "_createdAt"
 	DocumentAttrUpdatedAt = "_updatedAt"
 )
@@ -44,6 +48,20 @@ func (d Document) ID() (DocumentID, bool) {
 	return "", false
 }
 
+func (d Document) Revision() (int, bool) {
+	rawRevision, exists := d[DocumentAttrRevision]
+	if !exists {
+		return 0, false
+	}
+
+	revision, ok := rawRevision.(int)
+	if ok {
+		return revision, true
+	}
+
+	return 0, false
+}
+
 func (d Document) CreatedAt() (time.Time, bool) {
 	return d.timeAttr(DocumentAttrCreatedAt)
 }

pkg/storage/driver/cache/blob_bucket.go

@@ -6,17 +6,16 @@ import (
 	"io"
 
 	"forge.cadoles.com/arcad/edge/pkg/storage"
-	"github.com/allegro/bigcache/v3"
-	"github.com/hashicorp/golang-lru/v2/expirable"
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver/cache/lfu"
 	"github.com/pkg/errors"
 	"gitlab.com/wpetit/goweb/logger"
 )
 
 type BlobBucket struct {
 	bucket        storage.BlobBucket
-	contentCache  *bigcache.BigCache
-	blobInfoCache *expirable.LRU[string, storage.BlobInfo]
-	bucketCache   *expirable.LRU[string, storage.BlobBucket]
+	blobCache     *lfu.Cache[string, []byte]
+	bucketCache   *lfu.Cache[string, storage.BlobBucket]
+	blobInfoCache *lfu.Cache[string, storage.BlobInfo]
 }
 
 // Close implements storage.BlobBucket.
@@ -39,7 +38,16 @@ func (b *BlobBucket) Delete(ctx context.Context, id storage.BlobID) error {
 // Get implements storage.BlobBucket.
 func (b *BlobBucket) Get(ctx context.Context, id storage.BlobID) (storage.BlobInfo, error) {
 	key := b.getCacheKey(id)
-	if blobInfo, ok := b.blobInfoCache.Get(key); ok {
+	blobInfo, err := b.blobInfoCache.Get(key)
+	if err != nil && !errors.Is(err, lfu.ErrNotFound) {
+		logger.Error(
+			ctx, "could not retrieve blob info from cache",
+			logger.F("cacheKey", key),
+			logger.CapturedE(errors.WithStack(err)),
+		)
+	}
+
+	if blobInfo != nil {
 		logger.Debug(
 			ctx, "found blob info in cache",
 			logger.F("cacheKey", key),
@@ -52,13 +60,25 @@ func (b *BlobBucket) Get(ctx context.Context, id storage.BlobID) (storage.BlobIn
 	if err != nil {
 		if errors.Is(err, storage.ErrBucketClosed) {
 			b.clearCache(ctx, id)
-			b.bucketCache.Remove(b.Name())
+			if err := b.bucketCache.Delete(b.Name()); err != nil && !errors.Is(err, lfu.ErrNotFound) {
+				logger.Error(
+					ctx, "could not delete bucket from cache",
+					logger.F("cacheKey", b.Name()),
+					logger.CapturedE(errors.WithStack(err)),
+				)
+			}
 		}
 
 		return nil, errors.WithStack(err)
 	}
 
-	b.blobInfoCache.Add(key, info)
+	if err := b.blobInfoCache.Set(key, info); err != nil {
+		logger.Error(
+			ctx, "could not set blob info in cache",
+			logger.F("cacheKey", key),
+			logger.CapturedE(errors.WithStack(err)),
+		)
+	}
 
 	return info, nil
 }
@@ -68,7 +88,13 @@ func (b *BlobBucket) List(ctx context.Context) ([]storage.BlobInfo, error) {
 	infos, err := b.bucket.List(ctx)
 	if err != nil {
 		if errors.Is(err, storage.ErrBucketClosed) {
-			b.bucketCache.Remove(b.Name())
+			if err := b.bucketCache.Delete(b.Name()); err != nil && !errors.Is(err, lfu.ErrNotFound) {
+				logger.Error(
+					ctx, "could not delete bucket from cache",
+					logger.F("cacheKey", b.Name()),
+					logger.CapturedE(errors.WithStack(err)),
+				)
+			}
 		}
 
 		return nil, errors.WithStack(err)
@@ -76,7 +102,13 @@ func (b *BlobBucket) List(ctx context.Context) ([]storage.BlobInfo, error) {
 
 	for _, ifo := range infos {
 		key := b.getCacheKey(ifo.ID())
-		b.blobInfoCache.Add(key, ifo)
+		if err := b.blobInfoCache.Set(key, ifo); err != nil {
+			logger.Error(
+				ctx, "could not set blob info in cache",
+				logger.F("cacheKey", key),
+				logger.CapturedE(errors.WithStack(err)),
+			)
+		}
 	}
 
 	return infos, nil
@@ -93,7 +125,6 @@ func (b *BlobBucket) NewReader(ctx context.Context, id storage.BlobID) (io.ReadS
 		logger.Debug(
 			ctx, "found blob content in cache",
 			logger.F("cacheKey", b.getCacheKey(id)),
-			logger.F("cacheStats", b.contentCache.Stats()),
 		)
 		return cached, nil
 	}
@@ -102,7 +133,13 @@ func (b *BlobBucket) NewReader(ctx context.Context, id storage.BlobID) (io.ReadS
 	if err != nil {
 		if errors.Is(err, storage.ErrBucketClosed) {
 			b.clearCache(ctx, id)
-			b.bucketCache.Remove(b.Name())
+			if err := b.bucketCache.Delete(b.Name()); err != nil && !errors.Is(err, lfu.ErrNotFound) {
+				logger.Error(
+					ctx, "could not delete bucket from cache",
+					logger.F("cacheKey", b.Name()),
+					logger.CapturedE(errors.WithStack(err)),
+				)
+			}
 		}
 
 		return nil, errors.WithStack(err)
@@ -110,7 +147,7 @@ func (b *BlobBucket) NewReader(ctx context.Context, id storage.BlobID) (io.ReadS
 
 	return &readCacher{
 		reader: reader,
-		cache:  b.contentCache,
+		cache:  b.blobCache,
 		key:    b.getCacheKey(id),
 	}, nil
 }
@@ -121,13 +158,13 @@ func (b *BlobBucket) getCacheKey(id storage.BlobID) string {
 
 func (b *BlobBucket) inContentCache(id storage.BlobID) (io.ReadSeekCloser, bool) {
 	key := b.getCacheKey(id)
-	data, err := b.contentCache.Get(key)
+	data, err := b.blobCache.Get(key)
 	if err != nil {
-		if errors.Is(err, bigcache.ErrEntryNotFound) {
+		if errors.Is(err, lfu.ErrNotFound) {
 			return nil, false
 		}
 
-		logger.Error(context.Background(), "could not retrieve cache value", logger.CapturedE(errors.WithStack(err)))
+		logger.Error(context.Background(), "could not retrieve cached value", logger.CapturedE(errors.WithStack(err)))
 
 		return nil, false
 	}
@@ -140,11 +177,17 @@ func (b *BlobBucket) clearCache(ctx context.Context, id storage.BlobID) {
 
 	logger.Debug(ctx, "clearing cache", logger.F("cacheKey", key))
 
-	if err := b.contentCache.Delete(key); err != nil {
-		logger.Error(ctx, "could not clear cache", logger.CapturedE(errors.WithStack(err)))
+	if err := b.blobCache.Delete(key); err != nil && !errors.Is(err, lfu.ErrNotFound) {
+		logger.Error(ctx, "could not clear cache", logger.F("cacheKey", key), logger.CapturedE(errors.WithStack(err)))
 	}
 
-	b.blobInfoCache.Remove(key)
+	if err := b.blobInfoCache.Delete(key); err != nil {
+		logger.Error(
+			ctx, "could not delete blob info from cache",
+			logger.F("cacheKey", key),
+			logger.CapturedE(errors.WithStack(err)),
+		)
+	}
 }
 
 // NewWriter implements storage.BlobBucket.
@@ -154,7 +197,13 @@ func (b *BlobBucket) NewWriter(ctx context.Context, id storage.BlobID) (io.Write
 	writer, err := b.bucket.NewWriter(ctx, id)
 	if err != nil {
 		if errors.Is(err, storage.ErrBucketClosed) {
-			b.bucketCache.Remove(b.Name())
+			if err := b.bucketCache.Delete(b.Name()); err != nil && !errors.Is(err, lfu.ErrNotFound) {
+				logger.Error(
+					ctx, "could not delete bucket from cache",
+					logger.F("cacheKey", b.Name()),
+					logger.CapturedE(errors.WithStack(err)),
+				)
+			}
 		}
 
 		return nil, errors.WithStack(err)
@@ -168,7 +217,13 @@ func (b *BlobBucket) Size(ctx context.Context) (int64, error) {
 	size, err := b.bucket.Size(ctx)
 	if err != nil {
 		if errors.Is(err, storage.ErrBucketClosed) {
-			b.bucketCache.Remove(b.Name())
+			if err := b.bucketCache.Delete(b.Name()); err != nil && !errors.Is(err, lfu.ErrNotFound) {
+				logger.Error(
+					ctx, "could not delete bucket from cache",
+					logger.F("cacheKey", b.Name()),
+					logger.CapturedE(errors.WithStack(err)),
+				)
+			}
 		}
 
 		return 0, errors.WithStack(err)

pkg/storage/driver/cache/blob_store.go

@@ -4,17 +4,16 @@ import (
 	"context"
 
 	"forge.cadoles.com/arcad/edge/pkg/storage"
-	"github.com/allegro/bigcache/v3"
-	"github.com/hashicorp/golang-lru/v2/expirable"
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver/cache/lfu"
 	"github.com/pkg/errors"
 	"gitlab.com/wpetit/goweb/logger"
 )
 
 type BlobStore struct {
 	store         storage.BlobStore
-	contentCache  *bigcache.BigCache
-	bucketCache   *expirable.LRU[string, storage.BlobBucket]
-	blobInfoCache *expirable.LRU[string, storage.BlobInfo]
+	blobCache     *lfu.Cache[string, []byte]
+	bucketCache   *lfu.Cache[string, storage.BlobBucket]
+	blobInfoCache *lfu.Cache[string, storage.BlobInfo]
 }
 
 // DeleteBucket implements storage.BlobStore.
@@ -23,7 +22,7 @@ func (s *BlobStore) DeleteBucket(ctx context.Context, name string) error {
 		return errors.WithStack(err)
 	}
 
-	s.bucketCache.Remove(name)
+	s.bucketCache.Delete(name)
 
 	return nil
 }
@@ -40,28 +39,40 @@ func (s *BlobStore) ListBuckets(ctx context.Context) ([]string, error) {
 
 // OpenBucket implements storage.BlobStore.
 func (s *BlobStore) OpenBucket(ctx context.Context, name string) (storage.BlobBucket, error) {
-	bucket, ok := s.bucketCache.Get(name)
-	if ok {
+	bucket, err := s.bucketCache.Get(name)
+	if err == nil {
 		logger.Debug(ctx, "found bucket in cache", logger.F("name", name))
 
 		return &BlobBucket{
 			bucket:        bucket,
-			contentCache:  s.contentCache,
+			blobCache:     s.blobCache,
 			blobInfoCache: s.blobInfoCache,
 			bucketCache:   s.bucketCache,
 		}, nil
 	}
 
-	bucket, err := s.store.OpenBucket(ctx, name)
+	if err != nil && !errors.Is(err, lfu.ErrNotFound) {
+		logger.Error(ctx, "could not retrieve bucket from cache",
+			logger.F("cacheKey", name),
+			logger.CapturedE(errors.WithStack(err)),
+		)
+	}
+
+	bucket, err = s.store.OpenBucket(ctx, name)
 	if err != nil {
 		return nil, errors.WithStack(err)
 	}
 
-	s.bucketCache.Add(name, bucket)
+	if err := s.bucketCache.Set(name, bucket); err != nil {
+		logger.Error(ctx, "could not set bucket in cache",
+			logger.F("cacheKey", name),
+			logger.CapturedE(errors.WithStack(err)),
+		)
+	}
 
 	return &BlobBucket{
 		bucket:        bucket,
-		contentCache:  s.contentCache,
+		blobCache:     s.blobCache,
 		blobInfoCache: s.blobInfoCache,
 		bucketCache:   s.bucketCache,
 	}, nil
@@ -70,30 +81,36 @@ func (s *BlobStore) OpenBucket(ctx context.Context, name string) (storage.BlobBu
 func NewBlobStore(store storage.BlobStore, funcs ...OptionFunc) (*BlobStore, error) {
 	options := NewOptions(funcs...)
 
-	cacheConfig := bigcache.DefaultConfig(options.CacheTTL)
-	cacheConfig.Logger = &cacheLogger{}
+	blobCache := lfu.NewCache[string, []byte](
+		options.BlobCacheStore,
+		lfu.WithTTL[string, []byte](options.CacheTTL),
+		lfu.WithCapacity[string, []byte](options.BlobCacheSize),
+		lfu.WithGetValueSize[string, []byte](func(value []byte) (int, error) {
+			return len(value), nil
+		}),
+	)
 
-	contentCache, err := bigcache.New(context.Background(), cacheConfig)
-	if err != nil {
-		return nil, errors.WithStack(err)
-	}
+	blobBucketCache := lfu.NewCache[string, storage.BlobBucket](
+		options.BlobBucketCacheStore,
+		lfu.WithCapacity[string, storage.BlobBucket](options.BlobBucketCacheSize),
+		lfu.WithGetValueSize[string, storage.BlobBucket](func(value storage.BlobBucket) (int, error) {
+			return 1, nil
+		}),
+	)
 
-	onBlobBucketEvict := func(key string, bucket storage.BlobBucket) {
-		ctx := context.Background()
-		logger.Debug(ctx, "evicting blob bucket from cache", logger.F("cacheKey", key))
-
-		if err := bucket.Close(); err != nil {
-			logger.Error(ctx, "could not close bucket", logger.E(errors.WithStack(err)))
-		}
-	}
-
-	bucketCache := expirable.NewLRU[string, storage.BlobBucket](options.BucketCacheSize, onBlobBucketEvict, options.CacheTTL)
-	blobInfoCache := expirable.NewLRU[string, storage.BlobInfo](options.BlobInfoCacheSize, nil, options.CacheTTL)
+	blobInfoCache := lfu.NewCache[string, storage.BlobInfo](
+		options.BlobInfoCacheStore,
+		lfu.WithTTL[string, storage.BlobInfo](options.CacheTTL),
+		lfu.WithCapacity[string, storage.BlobInfo](options.BlobInfoCacheSize),
+		lfu.WithGetValueSize[string, storage.BlobInfo](func(value storage.BlobInfo) (int, error) {
+			return 1, nil
+		}),
+	)
 
 	return &BlobStore{
 		store:         store,
-		contentCache:  contentCache,
-		bucketCache:   bucketCache,
+		blobCache:     blobCache,
+		bucketCache:   blobBucketCache,
 		blobInfoCache: blobInfoCache,
 	}, nil
 }

pkg/storage/driver/cache/driver.go

@@ -1,17 +1,19 @@
 package cache
 
 import (
-	"context"
-	"fmt"
+	"bytes"
+	"io"
 	"net/url"
 	"strconv"
 	"time"
 
 	"forge.cadoles.com/arcad/edge/pkg/storage"
 	"forge.cadoles.com/arcad/edge/pkg/storage/driver"
-	"github.com/allegro/bigcache/v3"
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver/cache/lfu"
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver/cache/lfu/fs"
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver/cache/lfu/memory"
+	"github.com/inhies/go-bytesize"
 	"github.com/pkg/errors"
-	"gitlab.com/wpetit/goweb/logger"
 )
 
 func init() {
@@ -30,66 +32,87 @@ func blobStoreFactory(dsn *url.URL) (storage.BlobStore, error) {
 
 	blobStoreOptionFuncs := make([]OptionFunc, 0)
 
-	rawCacheTTL := query.Get("cacheTTL")
-	if rawCacheTTL != "" {
-		query.Del("cacheTTL")
-
-		ttl, err := time.ParseDuration(rawCacheTTL)
-		if err != nil {
-			return nil, errors.Wrap(err, "could not parse url parameter 'cacheTTL'")
+	cacheTTL, err := parseDuration(&query, "cacheTTL")
+	if err != nil {
+		if !errors.Is(err, errNotFound) {
+			return nil, errors.WithStack(err)
 		}
 
-		blobStoreOptionFuncs = append(blobStoreOptionFuncs, WithCacheTTL(ttl))
+		cacheTTL = time.Hour
 	}
 
-	rawCacheShards := query.Get("blobCacheShards")
-	if rawCacheShards != "" {
-		query.Del("blobCacheShards")
+	blobStoreOptionFuncs = append(blobStoreOptionFuncs, WithCacheTTL(cacheTTL))
 
-		cacheShards, err := strconv.ParseInt(rawCacheShards, 10, 32)
-		if err != nil {
-			return nil, errors.Wrap(err, "could not parse url parameter 'blobCacheShards'")
+	blobBucketCacheSize, err := parseInt(&query, "blobBucketCacheSize")
+	if err != nil {
+		if !errors.Is(err, errNotFound) {
+			return nil, errors.WithStack(err)
 		}
 
-		blobStoreOptionFuncs = append(blobStoreOptionFuncs, WithBlobCacheShards(int(cacheShards)))
+		blobBucketCacheSize = 16
 	}
 
-	rawBlobCacheMaxMemorySize := query.Get("blobCacheMaxMemorySize")
-	if rawBlobCacheMaxMemorySize != "" {
-		query.Del("blobCacheMaxMemorySize")
+	blobStoreOptionFuncs = append(blobStoreOptionFuncs, WithBlobBucketCacheSize(int(blobBucketCacheSize)))
 
-		blobCacheMaxMemorySize, err := strconv.ParseInt(rawBlobCacheMaxMemorySize, 10, 32)
-		if err != nil {
-			return nil, errors.Wrap(err, "could not parse url parameter 'blobCacheMaxMemorySize'")
+	blobBucketCacheStorePrefix := "blobBucketCacheStore"
+	blobBucketCacheStore, err := parseCacheStore[string, storage.BlobBucket](&query, blobBucketCacheStorePrefix)
+	if err != nil {
+		return nil, errors.WithStack(err)
+	}
+
+	blobStoreOptionFuncs = append(blobStoreOptionFuncs, WithBlobBucketCacheStore(blobBucketCacheStore))
+
+	bloInfoCacheSize, err := parseInt(&query, "bloInfoCacheSize")
+	if err != nil {
+		if !errors.Is(err, errNotFound) {
+			return nil, errors.WithStack(err)
 		}
 
-		blobStoreOptionFuncs = append(blobStoreOptionFuncs, WithBlobCacheMaxMemorySize(int(blobCacheMaxMemorySize)))
+		bloInfoCacheSize = 16
 	}
 
-	rawBlobBucketCacheSize := query.Get("blobBucketCacheSize")
-	if rawBlobBucketCacheSize != "" {
-		query.Del("blobBucketCacheSize")
+	blobStoreOptionFuncs = append(blobStoreOptionFuncs, WithBlobInfoCacheSize(int(bloInfoCacheSize)))
 
-		blobBucketCacheSize, err := strconv.ParseInt(rawBlobBucketCacheSize, 10, 32)
-		if err != nil {
-			return nil, errors.Wrap(err, "could not parse url parameter 'blobBucketCacheSize'")
+	blobInfoCacheStorePrefix := "blobInfoCacheStore"
+	blobInfoCacheStore, err := parseCacheStore[string, storage.BlobInfo](&query, blobInfoCacheStorePrefix)
+	if err != nil {
+		return nil, errors.WithStack(err)
+	}
+
+	blobStoreOptionFuncs = append(blobStoreOptionFuncs, WithBlobInfoCacheStore(blobInfoCacheStore))
+
+	blobCacheSize, err := parseByteSize(&query, "blobCacheSize")
+	if err != nil {
+		if !errors.Is(err, errNotFound) {
+			return nil, errors.WithStack(err)
 		}
 
-		blobStoreOptionFuncs = append(blobStoreOptionFuncs, WithBucketCacheSize(int(blobBucketCacheSize)))
+		blobCacheSize = 256e+6
 	}
 
-	rawBlobInfoCacheSize := query.Get("blobInfoCacheSize")
-	if rawBlobInfoCacheSize != "" {
-		query.Del("blobInfoCacheSize")
+	blobStoreOptionFuncs = append(blobStoreOptionFuncs, WithBlobCacheSize(int(blobCacheSize)))
 
-		blobInfoCacheSize, err := strconv.ParseInt(rawBlobInfoCacheSize, 10, 32)
-		if err != nil {
-			return nil, errors.Wrap(err, "could not parse url parameter 'blobInfoCacheSize'")
-		}
+	blobCacheStorePrefix := "blobCacheStore"
+	blobCacheStore, err := parseCacheStore[string, []byte](
+		&query, blobCacheStorePrefix,
+		fs.WithMarshalValue[string, []byte](func(value []byte) (io.Reader, error) {
+			return bytes.NewBuffer(value), nil
+		}),
+		fs.WithUnmarshalValue[string, []byte](func(r io.Reader) ([]byte, error) {
+			data, err := io.ReadAll(r)
+			if err != nil {
+				return nil, errors.WithStack(err)
+			}
 
-		blobStoreOptionFuncs = append(blobStoreOptionFuncs, WithBlobInfoCacheSize(int(blobInfoCacheSize)))
+			return data, nil
+		}),
+	)
+	if err != nil {
+		return nil, errors.WithStack(err)
 	}
 
+	blobStoreOptionFuncs = append(blobStoreOptionFuncs, WithBlobCacheStore(blobCacheStore))
+
 	url := &url.URL{
 		Scheme:   rawDriver,
 		Host:     dsn.Host,
@@ -110,10 +133,132 @@ func blobStoreFactory(dsn *url.URL) (storage.BlobStore, error) {
 	return store, nil
 }
 
-type cacheLogger struct{}
+var errNotFound = errors.New("not found")
 
-func (l *cacheLogger) Printf(format string, v ...interface{}) {
-	logger.Debug(context.Background(), fmt.Sprintf(format, v...))
+func parseString(query *url.Values, name string) (string, error) {
+	value := query.Get(name)
+	if value != "" {
+		query.Del(name)
+		return value, nil
+	}
+
+	return "", errors.WithStack(errNotFound)
 }
 
-var _ bigcache.Logger = &cacheLogger{}
+func parseByteSize(query *url.Values, name string) (bytesize.ByteSize, error) {
+	rawValue := query.Get(name)
+	if rawValue != "" {
+		query.Del(name)
+
+		value, err := bytesize.Parse(rawValue)
+		if err != nil {
+			return 0, errors.Wrapf(err, "could not parse url parameter '%s'", name)
+		}
+
+		return value, nil
+	}
+
+	return 0, errors.WithStack(errNotFound)
+}
+
+func parseInt(query *url.Values, name string) (int64, error) {
+	rawValue := query.Get(name)
+	if rawValue != "" {
+		query.Del(name)
+
+		value, err := strconv.ParseInt(rawValue, 10, 32)
+		if err != nil {
+			return 0, errors.Wrapf(err, "could not parse url parameter '%s'", name)
+		}
+
+		return value, nil
+	}
+
+	return 0, errors.WithStack(errNotFound)
+}
+
+func parseDuration(query *url.Values, name string) (time.Duration, error) {
+	rawValue := query.Get(name)
+	if rawValue != "" {
+		query.Del(name)
+
+		value, err := time.ParseDuration(rawValue)
+		if err != nil {
+			return 0, errors.Wrapf(err, "could not parse url parameter '%s'", name)
+		}
+
+		return value, nil
+	}
+
+	return 0, errors.WithStack(errNotFound)
+}
+
+const (
+	storeTypeFS     string = "fs"
+	storeTypeMemory string = "memory"
+)
+
+func parseCacheStore[K comparable, V any](query *url.Values, prefix string, optionFuncs ...any) (lfu.Store[K, V], error) {
+	storeTypeParam := prefix + "Type"
+	storeType, err := parseString(query, storeTypeParam)
+	if err != nil {
+		if errors.Is(err, errNotFound) {
+			storeType = storeTypeMemory
+		}
+	}
+
+	switch storeType {
+	case storeTypeFS:
+		store, err := parseFSCacheStore[K, V](query, prefix, optionFuncs...)
+		if err != nil {
+			return nil, errors.WithStack(err)
+		}
+
+		return store, nil
+
+	case storeTypeMemory:
+		store, err := parseMemoryCacheStore[K, V](query, prefix, optionFuncs...)
+		if err != nil {
+			return nil, errors.WithStack(err)
+		}
+
+		return store, nil
+	}
+
+	return nil, errors.Errorf("unexpected store type value '%s' for parameter '%s'", storeType, storeTypeParam)
+}
+
+func parseFSCacheStore[K comparable, V any](query *url.Values, prefix string, optionFuncs ...any) (*fs.Store[K, V], error) {
+	baseDirParam := prefix + "BaseDir"
+	baseDir, err := parseString(query, baseDirParam)
+	if err != nil {
+		if errors.Is(err, errNotFound) {
+			return nil, errors.Wrapf(err, "missing required url parameter '%s'", baseDirParam)
+		}
+
+		return nil, errors.WithStack(err)
+	}
+
+	funcs := make([]fs.OptionsFunc[K, V], 0)
+
+	for _, anyFn := range optionFuncs {
+		fn, ok := anyFn.(fs.OptionsFunc[K, V])
+		if !ok {
+			continue
+		}
+
+		funcs = append(funcs, fn)
+	}
+
+	store := fs.NewStore[K, V](baseDir, funcs...)
+
+	if err := store.Clear(); err != nil {
+		return nil, errors.WithStack(err)
+	}
+
+	return store, nil
+}
+
+func parseMemoryCacheStore[K comparable, V any](query *url.Values, prefix string, optionFuncs ...any) (*memory.Store[K, V], error) {
+	return memory.NewStore[K, V](), nil
+}

pkg/storage/driver/cache/lfu/cache.go

@@ -0,0 +1,349 @@
+package lfu
+
+import (
+	"slices"
+	"sync/atomic"
+	"time"
+
+	"github.com/pkg/errors"
+)
+
+var (
+	ErrNotFound           = errors.New("not found")
+	ErrSizeExceedCapacity = errors.New("size exceed capacity")
+	errExpired            = errors.New("expired")
+)
+
+type Cache[K comparable, V any] struct {
+	index *Map[K, *cacheItem[K, V]]
+	freqs *List[*frequencyItem[K, V]]
+
+	size atomic.Int32
+
+	capacity     int
+	store        Store[K, V]
+	getValueSize GetValueSizeFunc[V]
+	sync         *Synchronizer[K]
+
+	log LogFunc
+	ttl time.Duration
+}
+
+type cacheItem[K any, V any] struct {
+	key             K
+	size            int
+	time            atomic.Int64
+	frequencyParent *Element[*frequencyItem[K, V]]
+}
+
+func (i *cacheItem[K, V]) Expired(ttl time.Duration) bool {
+	if ttl == 0 {
+		return false
+	}
+
+	itemTime := time.Unix(i.time.Load(), 0)
+
+	// If item has expired, mark it as not found
+	return itemTime.Add(ttl).Before(time.Now())
+}
+
+func (i *cacheItem[K, V]) Refresh() {
+	i.time.Store(time.Now().Unix())
+}
+
+func newCacheItem[K any, V any](key K, size int) *cacheItem[K, V] {
+	item := &cacheItem[K, V]{
+		key:  key,
+		size: size,
+	}
+	item.time.Store(time.Now().Unix())
+	return item
+}
+
+type frequencyItem[K any, V any] struct {
+	entries *Map[*cacheItem[K, V], struct{}]
+	freq    int
+}
+
+func newFrequencyItem[K any, V any]() *frequencyItem[K, V] {
+	frequencyItem := &frequencyItem[K, V]{}
+	frequencyItem.entries = NewMap[*cacheItem[K, V], struct{}]()
+	return frequencyItem
+}
+
+func (c *Cache[K, V]) Set(key K, value V) error {
+	newItemSize, err := c.getValueSize(value)
+	if err != nil {
+		return errors.WithStack(err)
+	}
+
+	c.log("setting '%v' (size: %d)", key, newItemSize)
+
+	if newItemSize > int(c.capacity) {
+		return errors.Wrapf(ErrSizeExceedCapacity, "item size '%d' exceed cache total capacity of '%v'", newItemSize, c.capacity)
+	}
+
+	var sizeDelta int
+
+	err = c.sync.WriteTx(key, func() error {
+		if err := c.store.Set(key, value); err != nil {
+			return errors.WithStack(err)
+		}
+
+		item, ok := c.index.Get(key)
+		if ok {
+			oldItemSize := item.size
+			sizeDelta = -int(oldItemSize) + newItemSize
+			item.Refresh()
+		} else {
+			item = newCacheItem[K, V](key, newItemSize)
+			c.index.Set(key, item)
+			sizeDelta = newItemSize
+		}
+
+		c.size.Add(int32(sizeDelta))
+		c.increment(item)
+
+		return nil
+	})
+	if err != nil {
+		return errors.WithStack(err)
+	}
+
+	// Eviction, if needed
+	if err := c.Evict(key); err != nil {
+		return errors.WithStack(err)
+	}
+
+	return nil
+}
+
+func (c *Cache[K, V]) Get(key K) (V, error) {
+	var value V
+	err := c.sync.ReadTx(key, func(upgrade func(func())) error {
+		c.log("getting '%v'", key)
+
+		e, ok := c.index.Get(key)
+		if !ok {
+			return errors.WithStack(ErrNotFound)
+		}
+
+		if e.Expired(c.ttl) {
+			return errors.WithStack(errExpired)
+		}
+
+		v, err := c.store.Get(key)
+		if err != nil {
+			return errors.WithStack(err)
+		}
+
+		upgrade(func() {
+			c.increment(e)
+		})
+
+		value = v
+
+		return nil
+	})
+	if err != nil {
+		if errors.Is(err, errExpired) {
+			if err := c.Delete(key); err != nil {
+				return *new(V), errors.WithStack(err)
+			}
+
+			return *new(V), errors.WithStack(ErrNotFound)
+		}
+
+		return *new(V), errors.WithStack(err)
+	}
+
+	return value, nil
+}
+
+func (c *Cache[K, V]) Delete(key K) error {
+	err := c.sync.WriteTx(key, func() error {
+		c.log("deleting '%v'", key)
+
+		item, exists := c.index.Get(key)
+		if !exists {
+			return errors.WithStack(ErrNotFound)
+		}
+
+		if err := c.store.Delete(key); err != nil {
+			return errors.WithStack(err)
+		}
+
+		c.size.Add(-int32(item.size))
+
+		c.remove(item.frequencyParent, item)
+		c.index.Delete(key)
+
+		return nil
+	})
+	if err != nil {
+		return errors.WithStack(err)
+	}
+
+	return nil
+}
+
+func (c *Cache[K, V]) Evict(skipped ...K) error {
+	exceed, delta := c.atCapacity()
+	if exceed && delta > 0 {
+		if err := c.evict(delta, skipped...); err != nil {
+			return errors.WithStack(err)
+		}
+	}
+
+	return nil
+}
+
+func (c *Cache[K, V]) Len() int {
+	return c.index.Len()
+}
+
+func (c *Cache[K, V]) Size() int {
+	return int(c.size.Load())
+}
+
+func (c *Cache[K, V]) Capacity() int {
+	return c.capacity
+}
+
+func (c *Cache[K, V]) increment(item *cacheItem[K, V]) {
+	currentFrequencyElement := item.frequencyParent
+	var nextFrequencyAmount int
+	var nextFrequencyElement *Element[*frequencyItem[K, V]]
+
+	if currentFrequencyElement == nil {
+		nextFrequencyAmount = 1
+		nextFrequencyElement = c.freqs.First()
+	} else {
+		atomicFrequencyItem := c.freqs.Value(currentFrequencyElement)
+		nextFrequencyAmount = atomicFrequencyItem.freq + 1
+		nextFrequencyElement = c.freqs.Next(currentFrequencyElement)
+	}
+
+	var nextFrequency *frequencyItem[K, V]
+	if nextFrequencyElement != nil {
+		nextFrequency = c.freqs.Value(nextFrequencyElement)
+	}
+
+	if nextFrequencyElement == nil || nextFrequency == nil || nextFrequency.freq != nextFrequencyAmount {
+		newFrequencyItem := newFrequencyItem[K, V]()
+		newFrequencyItem.freq = nextFrequencyAmount
+
+		if currentFrequencyElement == nil {
+			nextFrequencyElement = c.freqs.PushFront(newFrequencyItem)
+		} else {
+			nextFrequencyElement = c.freqs.InsertValueAfter(newFrequencyItem, currentFrequencyElement)
+		}
+	}
+
+	item.frequencyParent = nextFrequencyElement
+
+	nextFrequency = c.freqs.Value(nextFrequencyElement)
+	nextFrequency.entries.Set(item, struct{}{})
+
+	if currentFrequencyElement != nil {
+		c.remove(currentFrequencyElement, item)
+	}
+}
+
+func (c *Cache[K, V]) remove(listItem *Element[*frequencyItem[K, V]], item *cacheItem[K, V]) {
+	entries := c.freqs.Value(listItem).entries
+
+	entries.Delete(item)
+}
+
+func (c *Cache[K, V]) atCapacity() (bool, int) {
+	size, capacity := c.Size(), c.Capacity()
+	c.log("cache stats: %d/%d", size, capacity)
+	return size >= capacity, size - capacity
+}
+
+func (c *Cache[K, V]) evict(total int, skipped ...K) error {
+	if total == 0 {
+		return nil
+	}
+
+	frequencyElement := c.freqs.First()
+	if frequencyElement == nil {
+		c.log("no frequency element")
+		return nil
+	}
+
+	for evicted := 0; evicted < total; {
+		c.log("running eviction: [to_evict:%d, evicted: %d]", total, evicted)
+
+		c.log("first frequency element %p", frequencyElement)
+
+		frequencyItem := c.freqs.Value(frequencyElement)
+		if frequencyItem == nil {
+			return nil
+		}
+
+		entries := frequencyItem.entries
+
+		if entries.Len() == 0 {
+			c.log("no frequency entries")
+			frequencyElement = c.freqs.Next(frequencyElement)
+			continue
+		}
+
+		var rangeErr error
+		entries.Range(func(key, v any) bool {
+			if evicted >= total {
+				c.log("evicted enough (%d >= %d), stopping", evicted, total)
+				return false
+			}
+
+			entry, _ := key.(*cacheItem[K, V])
+
+			if slices.Contains(skipped, entry.key) {
+				c.log("skipping key '%v'", entry.key)
+				return true
+			}
+
+			if err := c.Delete(entry.key); err != nil {
+				if errors.Is(err, ErrNotFound) {
+					c.log("key '%s' not found", entry.key)
+					// Cleanup obsolete frequency
+					c.remove(frequencyElement, entry)
+					return true
+				}
+
+				rangeErr = errors.WithStack(err)
+				return false
+			}
+
+			c.log("evicted key '%v' (size: %d)", entry.key, entry.size)
+
+			evicted += int(entry.size)
+
+			return true
+		})
+		if rangeErr != nil {
+			return errors.WithStack(rangeErr)
+		}
+	}
+
+	return nil
+}
+
+func NewCache[K comparable, V any](store Store[K, V], funcs ...OptionsFunc[K, V]) *Cache[K, V] {
+	opts := DefaultOptions[K, V](funcs...)
+
+	cache := &Cache[K, V]{
+		index:        NewMap[K, *cacheItem[K, V]](),
+		freqs:        NewList[*frequencyItem[K, V]](),
+		capacity:     opts.Capacity,
+		store:        store,
+		getValueSize: opts.GetValueSize,
+		sync:         NewSynchronizer[K](),
+		log:          opts.Log,
+		ttl:          opts.TTL,
+	}
+
+	return cache
+}

pkg/storage/driver/cache/lfu/fs/cache_test.go

@@ -0,0 +1,37 @@
+package fs
+
+import (
+	"bytes"
+	"io"
+	"path/filepath"
+	"testing"
+
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver/cache/lfu"
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver/cache/lfu/testsuite"
+	"github.com/pkg/errors"
+)
+
+func TestCacheWithFSStore(t *testing.T) {
+	testsuite.TestCacheWithStore(t, func(testName string) lfu.Store[string, string] {
+		dir := filepath.Join("testdata", "testsuite", testName)
+		store := NewStore[string, string](dir,
+			WithMarshalValue[string, string](func(value string) (io.Reader, error) {
+				return bytes.NewBuffer([]byte(value)), nil
+			}),
+			WithUnmarshalValue[string, string](func(r io.Reader) (string, error) {
+				data, err := io.ReadAll(r)
+				if err != nil {
+					return "", errors.WithStack(err)
+				}
+
+				return string(data), nil
+			}),
+		)
+
+		if err := store.Clear(); err != nil {
+			panic(errors.WithStack(err))
+		}
+
+		return store
+	})
+}

pkg/storage/driver/cache/lfu/fs/hash.go

@@ -0,0 +1,19 @@
+package fs
+
+import (
+	"strconv"
+
+	"github.com/mitchellh/hashstructure/v2"
+	"github.com/pkg/errors"
+)
+
+func DefaultGetPath[K comparable](key K) ([]string, error) {
+	uintHash, err := hashstructure.Hash(key, hashstructure.FormatV2, nil)
+	if err != nil {
+		return nil, errors.WithStack(err)
+	}
+
+	hash := strconv.FormatUint(uintHash, 16)
+
+	return []string{hash}, nil
+}

pkg/storage/driver/cache/lfu/fs/marshal.go

@@ -0,0 +1,31 @@
+package fs
+
+import (
+	"bytes"
+	"encoding/gob"
+	"io"
+
+	"github.com/pkg/errors"
+)
+
+func DefaultMarshalValue[V any](value V) (io.Reader, error) {
+	var buf bytes.Buffer
+	encoder := gob.NewEncoder(&buf)
+
+	if err := encoder.Encode(value); err != nil {
+		return nil, errors.WithStack(err)
+	}
+
+	return &buf, nil
+}
+
+func DefaultUnmarshalValue[V any](d io.Reader) (V, error) {
+	var value V
+	encoder := gob.NewDecoder(d)
+
+	if err := encoder.Decode(&value); err != nil {
+		return *new(V), errors.WithStack(err)
+	}
+
+	return value, nil
+}

pkg/storage/driver/cache/lfu/fs/options.go

@@ -0,0 +1,45 @@
+package fs
+
+import "io"
+
+type GetPathFunc[K comparable] func(key K) ([]string, error)
+type MarshalValueFunc[V any] func(value V) (io.Reader, error)
+type UnmarshalValueFunc[V any] func(r io.Reader) (V, error)
+
+type Options[K comparable, V any] struct {
+	GetPath        GetPathFunc[K]
+	MarshalValue   MarshalValueFunc[V]
+	UnmarshalValue UnmarshalValueFunc[V]
+}
+
+type OptionsFunc[K comparable, V any] func(opts *Options[K, V])
+
+func DefaultOptions[K comparable, V any](funcs ...OptionsFunc[K, V]) *Options[K, V] {
+	opts := &Options[K, V]{
+		GetPath:        DefaultGetPath[K],
+		MarshalValue:   DefaultMarshalValue[V],
+		UnmarshalValue: DefaultUnmarshalValue[V],
+	}
+	for _, fn := range funcs {
+		fn(opts)
+	}
+	return opts
+}
+
+func WithGetPath[K comparable, V any](getKeyHash GetPathFunc[K]) OptionsFunc[K, V] {
+	return func(opts *Options[K, V]) {
+		opts.GetPath = getKeyHash
+	}
+}
+
+func WithMarshalValue[K comparable, V any](marshalValue MarshalValueFunc[V]) OptionsFunc[K, V] {
+	return func(opts *Options[K, V]) {
+		opts.MarshalValue = marshalValue
+	}
+}
+
+func WithUnmarshalValue[K comparable, V any](unmarshalValue UnmarshalValueFunc[V]) OptionsFunc[K, V] {
+	return func(opts *Options[K, V]) {
+		opts.UnmarshalValue = unmarshalValue
+	}
+}

pkg/storage/driver/cache/lfu/fs/store.go

@@ -0,0 +1,165 @@
+package fs
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"path/filepath"
+
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver/cache/lfu"
+	"github.com/pkg/errors"
+)
+
+type Store[K comparable, V any] struct {
+	baseDir        string
+	getPath        GetPathFunc[K]
+	marshalValue   MarshalValueFunc[V]
+	unmarshalValue UnmarshalValueFunc[V]
+}
+
+// Delete implements Store.
+func (s *Store[K, V]) Delete(key K) error {
+	path, err := s.getEntryPath(key)
+	if err != nil {
+		return errors.WithStack(err)
+	}
+
+	if err := os.Remove(path); err != nil && !errors.Is(err, os.ErrNotExist) {
+		return errors.WithStack(err)
+	}
+
+	return nil
+}
+
+// Get implements Store.
+func (s *Store[K, V]) Get(key K) (V, error) {
+	path, err := s.getEntryPath(key)
+	if err != nil {
+		return *new(V), errors.WithStack(err)
+	}
+
+	value, err := s.readValue(path)
+	if err != nil {
+		if errors.Is(err, os.ErrNotExist) {
+			return *new(V), errors.WithStack(lfu.ErrNotFound)
+		}
+
+		return *new(V), errors.WithStack(err)
+	}
+
+	return value, nil
+}
+
+// Set implements Store.
+func (s *Store[K, V]) Set(key K, value V) error {
+	path, err := s.getEntryPath(key)
+	if err != nil {
+		return errors.WithStack(err)
+	}
+
+	if err := s.writeValue(path, value); err != nil {
+		return errors.WithStack(err)
+	}
+
+	return nil
+}
+
+func (s *Store[K, V]) Clear() error {
+	if err := os.RemoveAll(s.baseDir); err != nil {
+		return errors.WithStack(err)
+	}
+
+	return nil
+}
+
+func (s *Store[K, V]) getEntryPath(k K) (string, error) {
+	path, err := s.getPath(k)
+	if err != nil {
+		return "", errors.WithStack(err)
+	}
+
+	path = append([]string{s.baseDir}, path...)
+	return filepath.Join(path...), nil
+}
+
+func (s *Store[K, V]) writeValue(path string, value V) error {
+	fi, err := os.Stat(path)
+	if err == nil && !fi.Mode().IsRegular() {
+		return fmt.Errorf("%s already exists and is not a regular file", path)
+	}
+
+	dir := filepath.Dir(path)
+
+	if err := os.MkdirAll(dir, 0750); err != nil {
+		return errors.WithStack(err)
+	}
+
+	f, err := os.CreateTemp(dir, filepath.Base(path)+".tmp")
+	if err != nil {
+		return errors.WithStack(err)
+	}
+
+	tmpName := f.Name()
+	defer func() {
+		if err != nil {
+			f.Close()
+			os.Remove(tmpName)
+		}
+	}()
+
+	reader, err := s.marshalValue(value)
+	if err != nil {
+		return errors.WithStack(err)
+	}
+
+	if _, err := io.Copy(f, reader); err != nil {
+		return errors.WithStack(err)
+	}
+
+	if err := f.Sync(); err != nil {
+		return errors.WithStack(err)
+	}
+
+	if err := f.Close(); err != nil {
+		return errors.WithStack(err)
+	}
+
+	if err := os.Rename(tmpName, path); err != nil {
+		return errors.WithStack(err)
+	}
+
+	return nil
+}
+
+func (s *Store[K, V]) readValue(path string) (V, error) {
+	file, err := os.Open(path)
+	if err != nil {
+		return *new(V), errors.WithStack(err)
+	}
+
+	defer func() {
+		if err := file.Close(); err != nil && !errors.Is(err, os.ErrClosed) {
+			panic(errors.WithStack(err))
+		}
+	}()
+
+	value, err := s.unmarshalValue(file)
+
+	if err != nil {
+		return *new(V), errors.WithStack(err)
+	}
+
+	return value, nil
+}
+
+func NewStore[K comparable, V any](baseDir string, funcs ...OptionsFunc[K, V]) *Store[K, V] {
+	opts := DefaultOptions[K, V](funcs...)
+	return &Store[K, V]{
+		baseDir:        baseDir,
+		getPath:        opts.GetPath,
+		unmarshalValue: opts.UnmarshalValue,
+		marshalValue:   opts.MarshalValue,
+	}
+}
+
+var _ lfu.Store[string, int] = &Store[string, int]{}

pkg/storage/driver/cache/lfu/fs/testdata/.gitignore

@@ -0,0 +1,2 @@
+*
+!.gitignore

pkg/storage/driver/cache/lfu/list.go

@@ -0,0 +1,203 @@
+package lfu
+
+import (
+	"sync/atomic"
+)
+
+type List[T any] struct {
+	root *Element[T]
+	len  atomic.Int32
+	sync *Synchronizer[*Element[T]]
+}
+
+func (l *List[T]) First() *Element[T] {
+	if l.Len() == 0 {
+		return nil
+	}
+
+	var next *Element[T]
+	l.sync.ReadTx(l.root, func(upgrade func(func())) error {
+		next = l.root.next
+		return nil
+	})
+
+	return next
+}
+
+func (l *List[T]) Last() *Element[T] {
+	if l.Len() == 0 {
+		return nil
+	}
+
+	var prev *Element[T]
+	l.sync.ReadTx(l.root, func(upgrade func(func())) error {
+		prev = l.root.prev
+		return nil
+	})
+
+	return prev
+}
+
+func (l *List[T]) Prev(e *Element[T]) *Element[T] {
+	var prev *Element[T]
+	l.sync.ReadTx(e, func(upgrade func(func())) error {
+		prev = e.prev
+		return nil
+	})
+
+	return prev
+}
+
+func (l *List[T]) Next(e *Element[T]) *Element[T] {
+	var next *Element[T]
+	l.sync.ReadTx(e, func(upgrade func(func())) error {
+		next = e.next
+		return nil
+	})
+
+	return next
+}
+
+func (l *List[T]) Value(e *Element[T]) T {
+	var value T
+	l.sync.ReadTx(e, func(upgrade func(func())) error {
+		value = e.value
+		return nil
+	})
+
+	return value
+}
+
+func (l *List[T]) PushFront(v T) *Element[T] {
+	return l.InsertValueAfter(v, l.root)
+}
+
+func (l *List[T]) PushBack(v T) *Element[T] {
+	return l.InsertValueAfter(v, l.root)
+}
+
+func (l *List[T]) Remove(e *Element[T]) {
+	l.remove(e)
+}
+
+func (l *List[T]) Len() int {
+	return int(l.len.Load())
+}
+
+func (l *List[T]) insertAfter(e *Element[T], at *Element[T]) *Element[T] {
+	l.sync.ReadTx(e, func(upgrade func(fn func())) error {
+		var next *Element[T]
+		l.sync.ReadTx(at, func(upgrade func(func())) error {
+			next = at.next
+			return nil
+		})
+
+		upgrade(func() {
+			e.prev = at
+			e.next = next
+			e.list = l
+		})
+
+		if e.prev != nil {
+			l.sync.WriteTx(e.prev, func() error {
+				e.prev.next = e
+				return nil
+			})
+		}
+
+		if e.next != nil {
+			l.sync.WriteTx(e.next, func() error {
+				e.next.prev = e
+				return nil
+			})
+		}
+
+		return nil
+	})
+
+	l.len.Add(1)
+
+	return e
+}
+
+func (l *List[T]) InsertValueAfter(v T, at *Element[T]) *Element[T] {
+	e := NewElement[T](v)
+	return l.insertAfter(e, at)
+}
+
+func (l *List[T]) remove(e *Element[T]) {
+	if e == nil && e == l.root {
+		return
+	}
+
+	l.sync.ReadTx(e, func(upgrade func(fn func())) error {
+		if e.prev != nil {
+			if e.prev == e {
+				upgrade(func() {
+					e.prev.next = e.next
+				})
+			} else {
+				l.sync.WriteTx(e.prev, func() error {
+					e.prev.next = e.next
+					return nil
+				})
+			}
+		}
+
+		if e.next != nil {
+			if e.next == e {
+				upgrade(func() {
+					e.next.prev = e.prev
+				})
+			} else {
+				l.sync.WriteTx(e.next, func() error {
+					e.next.prev = e.prev
+					return nil
+				})
+			}
+		}
+
+		upgrade(func() {
+			e.next = nil
+			e.prev = nil
+			e.list = nil
+		})
+
+		return nil
+	})
+
+	l.sync.Remove(e)
+	l.len.Add(-1)
+}
+
+func NewList[T any]() *List[T] {
+	root := NewElement(*new(T))
+	root.next = root
+	root.prev = root
+
+	list := &List[T]{
+		sync: NewSynchronizer[*Element[T]](),
+	}
+
+	root.list = list
+	list.root = root
+
+	return list
+}
+
+type Element[T any] struct {
+	prev  *Element[T]
+	next  *Element[T]
+	list  *List[T]
+	value T
+}
+
+func NewElement[T any](v T) *Element[T] {
+	element := &Element[T]{
+		prev:  nil,
+		next:  nil,
+		list:  nil,
+		value: v,
+	}
+	return element
+}

pkg/storage/driver/cache/lfu/map.go

@@ -0,0 +1,67 @@
+package lfu
+
+import (
+	"sync"
+	"sync/atomic"
+)
+
+type Map[K comparable, V any] struct {
+	size  atomic.Int32
+	inner sync.Map
+}
+
+func (m *Map[K, V]) Get(key K) (V, bool) {
+	raw, exists := m.inner.Load(key)
+	if !exists {
+		return *new(V), false
+	}
+
+	value, ok := raw.(V)
+	if !ok {
+		return *new(V), false
+	}
+
+	return value, true
+}
+
+func (m *Map[K, V]) GetOrSet(key K, defaultValue V) (V, bool) {
+	raw, loaded := m.inner.LoadOrStore(key, defaultValue)
+	if !loaded {
+		m.size.Add(1)
+	}
+
+	value, ok := raw.(V)
+	if !ok {
+		return *new(V), loaded
+	}
+
+	return value, loaded
+}
+
+func (m *Map[K, V]) Set(key K, value V) {
+	_, loaded := m.inner.Swap(key, value)
+	if !loaded {
+		m.size.Add(1)
+	}
+}
+
+func (m *Map[K, V]) Delete(key K) {
+	_, existed := m.inner.LoadAndDelete(key)
+	if existed {
+		m.size.Add(-1)
+	}
+}
+
+func (m *Map[K, V]) Range(fn func(key, value any) bool) {
+	m.inner.Range(fn)
+}
+
+func (m *Map[K, V]) Len() int {
+	return int(m.size.Load())
+}
+
+func NewMap[K comparable, V any]() *Map[K, V] {
+	return &Map[K, V]{
+		inner: sync.Map{},
+	}
+}

pkg/storage/driver/cache/lfu/memory/cache_test.go

@@ -0,0 +1,14 @@
+package memory
+
+import (
+	"testing"
+
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver/cache/lfu"
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver/cache/lfu/testsuite"
+)
+
+func TestCacheWithMemoryStore(t *testing.T) {
+	testsuite.TestCacheWithStore(t, func(testName string) lfu.Store[string, string] {
+		return NewStore[string, string]()
+	})
+}

pkg/storage/driver/cache/lfu/memory/memory.go

@@ -0,0 +1,40 @@
+package memory
+
+import (
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver/cache/lfu"
+	"github.com/pkg/errors"
+)
+
+type Store[K comparable, V any] struct {
+	index *lfu.Map[K, V]
+}
+
+// Delete implements Store.
+func (s *Store[K, V]) Delete(key K) error {
+	s.index.Delete(key)
+	return nil
+}
+
+// Get implements Store.
+func (s *Store[K, V]) Get(key K) (V, error) {
+	value, exists := s.index.Get(key)
+	if !exists {
+		return *new(V), errors.WithStack(lfu.ErrNotFound)
+	}
+
+	return value, nil
+}
+
+// Set implements Store.
+func (s *Store[K, V]) Set(key K, value V) error {
+	s.index.Set(key, value)
+	return nil
+}
+
+func NewStore[K comparable, V any]() *Store[K, V] {
+	return &Store[K, V]{
+		index: lfu.NewMap[K, V](),
+	}
+}
+
+var _ lfu.Store[string, int] = &Store[string, int]{}

pkg/storage/driver/cache/lfu/options.go

@@ -0,0 +1,57 @@
+package lfu
+
+import "time"
+
+type GetValueSizeFunc[V any] func(value V) (int, error)
+
+type LogFunc func(format string, values ...any)
+
+func DefaultLogFunc(format string, values ...any) {
+
+}
+
+type Options[K comparable, V any] struct {
+	GetValueSize GetValueSizeFunc[V]
+	Capacity     int
+	Log          LogFunc
+	TTL          time.Duration
+}
+
+type OptionsFunc[K comparable, V any] func(opts *Options[K, V])
+
+func DefaultOptions[K comparable, V any](funcs ...OptionsFunc[K, V]) *Options[K, V] {
+	opts := &Options[K, V]{
+		GetValueSize: DefaultGetValueSize[V],
+		Capacity:     100,
+		Log:          DefaultLogFunc,
+		TTL:          0,
+	}
+	for _, fn := range funcs {
+		fn(opts)
+	}
+	return opts
+}
+
+func WithCapacity[K comparable, V any](capacity int) OptionsFunc[K, V] {
+	return func(opts *Options[K, V]) {
+		opts.Capacity = capacity
+	}
+}
+
+func WithGetValueSize[K comparable, V any](getValueSize GetValueSizeFunc[V]) OptionsFunc[K, V] {
+	return func(opts *Options[K, V]) {
+		opts.GetValueSize = getValueSize
+	}
+}
+
+func WithLog[K comparable, V any](fn LogFunc) OptionsFunc[K, V] {
+	return func(opts *Options[K, V]) {
+		opts.Log = fn
+	}
+}
+
+func WithTTL[K comparable, V any](ttl time.Duration) OptionsFunc[K, V] {
+	return func(opts *Options[K, V]) {
+		opts.TTL = ttl
+	}
+}

pkg/storage/driver/cache/lfu/size.go

@@ -0,0 +1,41 @@
+package lfu
+
+import (
+	"github.com/pkg/errors"
+)
+
+type Measurable interface {
+	Size() (int, error)
+}
+
+func DefaultGetValueSize[V any](value V) (int, error) {
+	switch v := any(value).(type) {
+	case int:
+		return v, nil
+	case int8:
+		return int(v), nil
+	case int32:
+		return int(v), nil
+	case int64:
+		return int(v), nil
+	case float32:
+		return int(v), nil
+	case float64:
+		return int(v), nil
+	case []byte:
+		return len(v), nil
+	case string:
+		return len(v), nil
+	}
+
+	if measurable, ok := any(value).(Measurable); ok {
+		size, err := measurable.Size()
+		if err != nil {
+			return 0, errors.WithStack(err)
+		}
+
+		return size, nil
+	}
+
+	return 0, errors.Errorf("could not retrieve size of type '%T'", value)
+}

pkg/storage/driver/cache/lfu/store.go

@@ -0,0 +1,7 @@
+package lfu
+
+type Store[K comparable, V any] interface {
+	Delete(key K) error
+	Set(key K, value V) error
+	Get(key K) (V, error)
+}

pkg/storage/driver/cache/lfu/synchronizer.go

@@ -0,0 +1,56 @@
+package lfu
+
+import (
+	"sync"
+
+	"github.com/pkg/errors"
+)
+
+type Synchronizer[K comparable] struct {
+	index *Map[K, *sync.RWMutex]
+}
+
+func (s *Synchronizer[K]) Remove(key K) {
+	s.index.Delete(key)
+}
+
+func (s *Synchronizer[K]) ReadTx(key K, fn func(upgrade func(fn func())) error) error {
+	mutex, _ := s.index.GetOrSet(key, &sync.RWMutex{})
+	mutex.RLock()
+	defer mutex.RUnlock()
+
+	upgrade := func(fn func()) {
+		mutex.RUnlock()
+		mutex.Lock()
+		defer func() {
+			mutex.Unlock()
+			mutex.RLock()
+		}()
+
+		fn()
+	}
+
+	if err := fn(upgrade); err != nil {
+		return errors.WithStack(err)
+	}
+
+	return nil
+}
+
+func (s *Synchronizer[K]) WriteTx(key K, fn func() error) error {
+	mutex, _ := s.index.GetOrSet(key, &sync.RWMutex{})
+	mutex.Lock()
+	defer mutex.Unlock()
+
+	if err := fn(); err != nil {
+		return errors.WithStack(err)
+	}
+
+	return nil
+}
+
+func NewSynchronizer[K comparable]() *Synchronizer[K] {
+	return &Synchronizer[K]{
+		index: NewMap[K, *sync.RWMutex](),
+	}
+}

pkg/storage/driver/cache/lfu/testsuite/main.go

@@ -0,0 +1,41 @@
+package testsuite
+
+import (
+	"reflect"
+	"runtime"
+	"strings"
+	"testing"
+
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver/cache/lfu"
+	"github.com/pkg/errors"
+)
+
+type StoreFactory func(testName string) lfu.Store[string, string]
+type testCase func(t *testing.T, store lfu.Store[string, string]) error
+
+var testCases = []testCase{
+	testSetGetDelete,
+	testEviction,
+	testConcurrent,
+	testMultipleSet,
+	testTTL,
+}
+
+func TestCacheWithStore(t *testing.T, factory StoreFactory) {
+	for _, tc := range testCases {
+		funcName := runtime.FuncForPC(reflect.ValueOf(tc).Pointer()).Name()
+		funcNameParts := strings.Split(funcName, "/")
+		testName := funcNameParts[len(funcNameParts)-1]
+		func(tc testCase) {
+			t.Run(testName, func(t *testing.T) {
+				t.Parallel()
+
+				store := factory(testName)
+
+				if err := tc(t, store); err != nil {
+					t.Fatalf("%+v", errors.WithStack(err))
+				}
+			})
+		}(tc)
+	}
+}

pkg/storage/driver/cache/lfu/testsuite/test_concurrent.go

@@ -0,0 +1,67 @@
+package testsuite
+
+import (
+	"fmt"
+	"sync"
+	"testing"
+
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver/cache/lfu"
+	"github.com/pkg/errors"
+)
+
+func testConcurrent(t *testing.T, store lfu.Store[string, string]) error {
+	const value = "foobar"
+	totalKeys := 25
+	totalSize := len(value) * totalKeys
+	capacity := totalSize / 2
+
+	cache := lfu.NewCache[string, string](store,
+		lfu.WithCapacity[string, string](capacity),
+		lfu.WithLog[string, string](t.Logf),
+	)
+
+	var wg sync.WaitGroup
+
+	wg.Add(totalKeys)
+
+	loops := totalKeys * 10
+
+	for i := 0; i < totalKeys; i++ {
+		key := fmt.Sprintf("key%d", i)
+		func(key string) {
+			go func() {
+				defer wg.Done()
+				for i := 0; i < loops; i++ {
+					if err := cache.Set(key, value); err != nil {
+						t.Errorf("%+v", errors.WithStack(err))
+					}
+				}
+			}()
+		}(key)
+	}
+
+	wg.Wait()
+
+	t.Logf("cache before final evict [capacity: %d, size: %d, len: %d]", cache.Capacity(), cache.Size(), cache.Len())
+
+	if err := cache.Evict(); err != nil {
+		t.Errorf("%+v", errors.WithStack(err))
+	}
+
+	t.Logf("cache after final evict [capacity: %d, size: %d, len: %d]", cache.Capacity(), cache.Size(), cache.Len())
+
+	expectedLength := capacity / len(value)
+	if e, g := expectedLength, cache.Len(); e < g {
+		t.Errorf("cache.Len(): expected <= %d, got %d", e, g)
+	}
+
+	if cache.Size() > capacity {
+		t.Errorf("cache.Size(): expected <= %d, got %d", capacity, cache.Size())
+	}
+
+	if e, g := expectedLength*len(value), cache.Size(); e < g {
+		t.Errorf("cache.Size(): expected <= %d, got %d", e, g)
+	}
+
+	return nil
+}

pkg/storage/driver/cache/lfu/testsuite/test_eviction.go

@@ -0,0 +1,70 @@
+package testsuite
+
+import (
+	"testing"
+
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver/cache/lfu"
+	"github.com/pkg/errors"
+)
+
+func testEviction(t *testing.T, store lfu.Store[string, string]) error {
+	cache := lfu.NewCache[string, string](store,
+		lfu.WithCapacity[string, string](10),
+		lfu.WithLog[string, string](t.Logf),
+	)
+
+	if err := cache.Set("key1", "key1"); err != nil {
+		return errors.WithStack(err)
+	}
+
+	if err := cache.Set("key2", "key2"); err != nil {
+		return errors.WithStack(err)
+	}
+
+	// Increment frequency of key2
+	if _, err := cache.Get("key2"); err != nil {
+		return errors.WithStack(err)
+	}
+
+	if e, g := 8, cache.Size(); e != g {
+		t.Errorf("cache.Size(): expected '%v', got '%v'", e, g)
+	}
+
+	if err := cache.Set("key3", "key3"); err != nil {
+		return errors.WithStack(err)
+	}
+
+	t.Logf("cache [capacity: %d, size: %d, len: %d]", cache.Capacity(), cache.Size(), cache.Len())
+
+	_, err := cache.Get("key1")
+	if err == nil {
+		t.Errorf("expected 'key1' to be evicted")
+	}
+
+	if !errors.Is(err, lfu.ErrNotFound) {
+		t.Errorf("expected err to be 'ErrNotFound'")
+	}
+
+	value, err := cache.Get("key2")
+	if err != nil {
+		return errors.WithStack(err)
+	}
+
+	if e, g := "key2", value; e < g {
+		t.Errorf("cache.Get(\"key2\"): expected %v, got %v", e, g)
+	}
+
+	if e, g := cache.Capacity(), cache.Size(); e < g {
+		t.Errorf("cache.Size(): expected <= %d, got %d", e, g)
+	}
+
+	if e, g := 2, cache.Len(); e != g {
+		t.Errorf("cache.Len(): expected %d, got %d", e, g)
+	}
+
+	if cache.Size() < 0 {
+		t.Errorf("cache.Size(): expected value >= 0, got %d", cache.Size())
+	}
+
+	return nil
+}

pkg/storage/driver/cache/lfu/testsuite/test_multiple_set.go

@@ -0,0 +1,80 @@
+package testsuite
+
+import (
+	"testing"
+
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver/cache/lfu"
+	"github.com/pkg/errors"
+)
+
+func testMultipleSet(t *testing.T, store lfu.Store[string, string]) error {
+	const (
+		key         = "mykey"
+		firstValue  = "foo"
+		secondValue = "bar"
+		thirdValue  = "foobar"
+	)
+
+	cache := lfu.NewCache[string, string](store)
+
+	if e, g := 0, cache.Size(); e != g {
+		t.Errorf("cache.Size(): expected '%v', got '%v'", e, g)
+	}
+
+	if err := cache.Set(key, firstValue); err != nil {
+		return errors.WithStack(err)
+	}
+
+	if e, g := len(firstValue), cache.Size(); e != g {
+		t.Errorf("cache.Size(): expected '%v', got '%v'", e, g)
+	}
+
+	retrieved, err := cache.Get(key)
+	if err != nil {
+		return errors.WithStack(err)
+	}
+
+	if e, g := firstValue, retrieved; e != g {
+		t.Errorf("cache.Get(key): expected '%v', got '%v'", e, g)
+	}
+
+	if err := cache.Set(key, secondValue); err != nil {
+		return errors.WithStack(err)
+	}
+
+	if e, g := len(secondValue), cache.Size(); e != g {
+		t.Errorf("cache.Size(): expected '%v', got '%v'", e, g)
+	}
+
+	retrieved, err = cache.Get(key)
+	if err != nil {
+		return errors.WithStack(err)
+	}
+
+	if e, g := secondValue, retrieved; e != g {
+		t.Errorf("cache.Get(key): expected '%v', got '%v'", e, g)
+	}
+
+	if err := cache.Set(key, thirdValue); err != nil {
+		return errors.WithStack(err)
+	}
+
+	if e, g := len(thirdValue), cache.Size(); e != g {
+		t.Errorf("cache.Size(): expected '%v', got '%v'", e, g)
+	}
+
+	retrieved, err = cache.Get(key)
+	if err != nil {
+		return errors.WithStack(err)
+	}
+
+	if e, g := thirdValue, retrieved; e != g {
+		t.Errorf("cache.Get(key): expected '%v', got '%v'", e, g)
+	}
+
+	if e, g := len(thirdValue), cache.Size(); e != g {
+		t.Errorf("cache.Size(): expected '%v', got '%v'", e, g)
+	}
+
+	return nil
+}

pkg/storage/driver/cache/lfu/testsuite/test_set_get_delete.go

@@ -0,0 +1,66 @@
+package testsuite
+
+import (
+	"testing"
+
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver/cache/lfu"
+	"github.com/pkg/errors"
+)
+
+func testSetGetDelete(t *testing.T, store lfu.Store[string, string]) error {
+	const (
+		key   = "mykey"
+		value = "foobar"
+	)
+
+	cache := lfu.NewCache[string, string](store, lfu.WithCapacity[string, string](10))
+
+	if e, g := 0, cache.Size(); e != g {
+		t.Errorf("cache.Size(): expected '%v', got '%v'", e, g)
+	}
+
+	if err := cache.Set(key, value); err != nil {
+		return errors.WithStack(err)
+	}
+
+	if e, g := len(value), cache.Size(); e != g {
+		t.Errorf("cache.Size(): expected '%v', got '%v'", e, g)
+	}
+
+	if e, g := 1, cache.Len(); e != g {
+		t.Errorf("cache.Len(): expected '%v', got '%v'", e, g)
+	}
+
+	retrieved, err := cache.Get(key)
+	if err != nil {
+		return errors.WithStack(err)
+	}
+
+	if e, g := value, retrieved; e != g {
+		t.Errorf("cache.Get(key): expected '%v', got '%v'", e, g)
+	}
+
+	if err := cache.Delete(key); err != nil {
+		return errors.WithStack(err)
+	}
+
+	if _, err := cache.Get(key); err == nil || !errors.Is(err, lfu.ErrNotFound) {
+		t.Errorf("cache.Get(key): err should be lfu.ErrNotFound, got '%v'", errors.WithStack(err))
+	}
+
+	if e, g := value, retrieved; e != g {
+		t.Errorf("cache.Get(key): expected '%v', got '%v'", e, g)
+	}
+
+	if e, g := 0, cache.Size(); e != g {
+		t.Errorf("cache.Size(): expected '%v', got '%v'", e, g)
+	}
+
+	if e, g := 0, cache.Len(); e != g {
+		t.Errorf("cache.Len(): expected '%v', got '%v'", e, g)
+	}
+
+	t.Logf("cache [capacity: %d, size: %d, len: %d]", cache.Capacity(), cache.Size(), cache.Len())
+
+	return nil
+}

pkg/storage/driver/cache/lfu/testsuite/test_ttl.go

@@ -0,0 +1,54 @@
+package testsuite
+
+import (
+	"testing"
+	"time"
+
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver/cache/lfu"
+	"github.com/pkg/errors"
+)
+
+func testTTL(t *testing.T, store lfu.Store[string, string]) error {
+	const (
+		key   = "mykey"
+		value = "foobar"
+	)
+
+	ttl := time.Second
+
+	cache := lfu.NewCache[string, string](store,
+		lfu.WithTTL[string, string](ttl),
+		lfu.WithCapacity[string, string](10),
+	)
+
+	if err := cache.Set(key, value); err != nil {
+		return errors.WithStack(err)
+	}
+
+	retrieved, err := cache.Get(key)
+	if err != nil {
+		return errors.WithStack(err)
+	}
+
+	if e, g := value, retrieved; e != g {
+		t.Errorf("cache.Get(key): expected '%v', got '%v'", e, g)
+	}
+
+	time.Sleep(ttl * 2)
+
+	if _, err := cache.Get(key); !errors.Is(err, lfu.ErrNotFound) {
+		t.Errorf("cache.Get(key): expected err == lfu.ErrNotFound, got '%v'", err)
+	}
+
+	t.Logf("cache [capacity: %d, size: %d, len: %d]", cache.Capacity(), cache.Size(), cache.Len())
+
+	if e, g := 0, cache.Size(); e != g {
+		t.Errorf("cache.Size(): expected '%v', got '%v'", e, g)
+	}
+
+	if e, g := 0, cache.Len(); e != g {
+		t.Errorf("cache.Len(): expected '%v', got '%v'", e, g)
+	}
+
+	return nil
+}

pkg/storage/driver/cache/options.go

@@ -1,24 +1,41 @@
 package cache
 
-import "time"
+import (
+	"time"
+
+	"forge.cadoles.com/arcad/edge/pkg/storage"
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver/cache/lfu"
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver/cache/lfu/memory"
+)
 
 type Options struct {
-	CacheTTL               time.Duration
-	BlobCacheMaxMemorySize int
-	BlobCacheShards        int
-	BucketCacheSize        int
-	BlobInfoCacheSize      int
+	CacheTTL time.Duration
+
+	BlobCacheStore lfu.Store[string, []byte]
+	// Maximum total size of cached data
+	BlobCacheSize int
+
+	BlobInfoCacheStore lfu.Store[string, storage.BlobInfo]
+	// Maximum number of blob infos
+	BlobInfoCacheSize int
+
+	BlobBucketCacheStore lfu.Store[string, storage.BlobBucket]
+	// Maximum number of blob bucket
+	BlobBucketCacheSize int
 }
 
 type OptionFunc func(opts *Options)
 
 func NewOptions(funcs ...OptionFunc) *Options {
+	defaultTTL := 60 * time.Minute
 	opts := &Options{
-		CacheTTL:               60 * time.Minute,
-		BlobCacheMaxMemorySize: 256,
-		BlobCacheShards:        1024,
-		BucketCacheSize:        16,
-		BlobInfoCacheSize:      512,
+		CacheTTL:             defaultTTL,
+		BlobCacheStore:       memory.NewStore[string, []byte](),
+		BlobCacheSize:        1e+9, // 1Gb
+		BlobInfoCacheStore:   memory.NewStore[string, storage.BlobInfo](),
+		BlobInfoCacheSize:    256,
+		BlobBucketCacheStore: memory.NewStore[string, storage.BlobBucket](),
+		BlobBucketCacheSize:  16,
 	}
 
 	for _, fn := range funcs {
@@ -34,21 +51,15 @@ func WithCacheTTL(ttl time.Duration) OptionFunc {
 	}
 }
 
-func WithBlobCacheMaxMemorySize(size int) OptionFunc {
+func WithBlobBucketCacheSize(size int) OptionFunc {
 	return func(opts *Options) {
-		opts.BlobCacheMaxMemorySize = size
+		opts.BlobBucketCacheSize = size
 	}
 }
 
-func WithBlobCacheShards(shards int) OptionFunc {
+func WithBlobBucketCacheStore(store lfu.Store[string, storage.BlobBucket]) OptionFunc {
 	return func(opts *Options) {
-		opts.BlobCacheShards = shards
-	}
-}
-
-func WithBucketCacheSize(size int) OptionFunc {
-	return func(opts *Options) {
-		opts.BucketCacheSize = size
+		opts.BlobBucketCacheStore = store
 	}
 }
 
@@ -57,3 +68,21 @@ func WithBlobInfoCacheSize(size int) OptionFunc {
 		opts.BlobInfoCacheSize = size
 	}
 }
+
+func WithBlobInfoCacheStore(store lfu.Store[string, storage.BlobInfo]) OptionFunc {
+	return func(opts *Options) {
+		opts.BlobInfoCacheStore = store
+	}
+}
+
+func WithBlobCacheSize(size int) OptionFunc {
+	return func(opts *Options) {
+		opts.BlobCacheSize = size
+	}
+}
+
+func WithBlobCacheStore(store lfu.Store[string, []byte]) OptionFunc {
+	return func(opts *Options) {
+		opts.BlobCacheStore = store
+	}
+}

pkg/storage/driver/cache/reader.go

@@ -1,18 +1,21 @@
 package cache
 
 import (
+	"bytes"
 	"context"
 	"fmt"
 	"io"
 
-	"github.com/allegro/bigcache/v3"
+	"cdr.dev/slog"
+	"forge.cadoles.com/arcad/edge/pkg/storage/driver/cache/lfu"
 	"github.com/pkg/errors"
 	"gitlab.com/wpetit/goweb/logger"
 )
 
 type readCacher struct {
 	reader io.ReadSeekCloser
-	cache  *bigcache.BigCache
+	cache  *lfu.Cache[string, []byte]
+	buf    bytes.Buffer
 	key    string
 }
 
@@ -22,6 +25,21 @@ func (r *readCacher) Close() error {
 		return errors.WithStack(err)
 	}
 
+	if err := r.cache.Set(r.key, r.buf.Bytes()); err != nil {
+		var logErr slog.Field
+		if errors.Is(err, lfu.ErrSizeExceedCapacity) {
+			logErr = logger.E(errors.WithStack(err))
+		} else {
+			logErr = logger.CapturedE(errors.WithStack(err))
+		}
+		logger.Error(context.Background(), "could not cache buffered data",
+			logger.F("cacheKey", r.key),
+			logErr,
+		)
+	}
+
+	r.buf.Reset()
+
 	return nil
 }
 
@@ -37,13 +55,9 @@ func (r *readCacher) Read(p []byte) (n int, err error) {
 	}
 
 	if length > 0 {
-		if err := r.cache.Append(r.key, p[:length]); err != nil {
+		if _, err := r.buf.Write(p[:length]); err != nil {
 			ctx := logger.With(context.Background(), logger.F("cacheKey", r.key))
 			logger.Error(ctx, "could not write to buffer", logger.CapturedE(errors.WithStack(err)))
-
-			if err := r.cache.Delete(r.key); err != nil {
-				logger.Error(ctx, "could not delete cache key", logger.CapturedE(errors.WithStack(err)))
-			}
 		}
 	}
 

pkg/storage/driver/sqlite/blob_store_test.go

@@ -24,7 +24,7 @@ func TestBlobStore(t *testing.T) {
 		t.Fatalf("%+v", errors.WithStack(err))
 	}
 
-	dsn := fmt.Sprintf("%s?_pragma=foreign_keys(1)&_pragma=busy_timeout=%d", file, (60 * time.Second).Milliseconds())
+	dsn := fmt.Sprintf("%s?_pragma=foreign_keys(1)&_pragma=busy_timeout=%d&_pragma=journal_mode=wal", file, (60 * time.Second).Milliseconds())
 	store := NewBlobStore(dsn)
 
 	testsuite.TestBlobStore(context.Background(), t, store)

pkg/storage/driver/sqlite/document_store.go

@@ -13,9 +13,14 @@ import (
 	"github.com/pkg/errors"
 	"gitlab.com/wpetit/goweb/logger"
 
+	_ "embed"
+
 	_ "modernc.org/sqlite"
 )
 
+//go:embed document_store.sql
+var documentStoreSchema string
+
 type DocumentStore struct {
 	getDB GetDBFunc
 }
@@ -48,7 +53,7 @@ func (s *DocumentStore) Get(ctx context.Context, collection string, id storage.D
 
 	err := s.withTx(ctx, func(tx *sql.Tx) error {
 		query := `
-		SELECT id, data, created_at, updated_at 
+		SELECT id, revision, data, created_at, updated_at 
 		FROM documents 
 		WHERE collection = $1 AND id = $2 
 		`
@@ -59,9 +64,10 @@ func (s *DocumentStore) Get(ctx context.Context, collection string, id storage.D
 			createdAt time.Time
 			updatedAt time.Time
 			data      JSONMap
+			revision  int
 		)
 
-		err := row.Scan(&id, &data, &createdAt, &updatedAt)
+		err := row.Scan(&id, &revision, &data, &createdAt, &updatedAt)
 		if err != nil {
 			if errors.Is(err, sql.ErrNoRows) {
 				return errors.WithStack(storage.ErrDocumentNotFound)
@@ -77,6 +83,7 @@ func (s *DocumentStore) Get(ctx context.Context, collection string, id storage.D
 		document = storage.Document(data)
 
 		document[storage.DocumentAttrID] = id
+		document[storage.DocumentAttrRevision] = revision
 		document[storage.DocumentAttrCreatedAt] = createdAt
 		document[storage.DocumentAttrUpdatedAt] = updatedAt
 
@@ -119,7 +126,7 @@ func (s *DocumentStore) Query(ctx context.Context, collection string, filter *fi
 		}
 
 		query := `
-		SELECT id, data, created_at, updated_at 
+		SELECT id, revision, data, created_at, updated_at 
 		FROM documents 
 		WHERE collection = $1 AND (` + criteria + `)
 		`
@@ -171,17 +178,19 @@ func (s *DocumentStore) Query(ctx context.Context, collection string, filter *fi
 		for rows.Next() {
 			var (
 				id        storage.DocumentID
+				revision  int
 				createdAt time.Time
 				updatedAt time.Time
 				data      JSONMap
 			)
 
-			if err := rows.Scan(&id, &data, &createdAt, &updatedAt); err != nil {
+			if err := rows.Scan(&id, &revision, &data, &createdAt, &updatedAt); err != nil {
 				return errors.WithStack(err)
 			}
 
 			document := storage.Document(data)
 			document[storage.DocumentAttrID] = id
+			document[storage.DocumentAttrRevision] = revision
 			document[storage.DocumentAttrCreatedAt] = createdAt
 			document[storage.DocumentAttrUpdatedAt] = updatedAt
 
@@ -206,22 +215,16 @@ func (s *DocumentStore) Upsert(ctx context.Context, collection string, document
 	var upsertedDocument storage.Document
 
 	err := s.withTx(ctx, func(tx *sql.Tx) error {
-		query := `
-		INSERT INTO documents (id, collection, data, created_at, updated_at) 
-		VALUES($1, $2, $3, $4, $4)
-		ON CONFLICT (id, collection) DO UPDATE SET
-			data = $3, updated_at = $4
-		RETURNING "id", "data", "created_at", "updated_at"
-		`
-
-		now := time.Now().UTC()
-
 		id, exists := document.ID()
 		if !exists || id == "" {
 			id = storage.NewDocumentID()
 		}
 
-		args := []any{id, collection, JSONMap(document), now, now}
+		query := `
+			SELECT revision FROM documents WHERE id = $1
+		`
+
+		args := []any{id}
 
 		logger.Debug(
 			ctx, "executing query",
@@ -231,14 +234,44 @@ func (s *DocumentStore) Upsert(ctx context.Context, collection string, document
 
 		row := tx.QueryRowContext(ctx, query, args...)
 
+		var storedRevision int
+
+		if err := row.Scan(&storedRevision); err != nil && !errors.Is(err, sql.ErrNoRows) {
+			return errors.WithStack(err)
+		}
+
+		revision, found := document.Revision()
+		if found && storedRevision != revision {
+			return errors.Wrapf(storage.ErrDocumentRevisionConflict, "document revision '%d' does not match stored '%d'", revision, storedRevision)
+		}
+
+		query = `
+		INSERT INTO documents (id, collection, data, created_at, updated_at) 
+		VALUES($1, $2, $3, $4, $4)
+		ON CONFLICT (id, collection) DO UPDATE SET
+			data = $3, updated_at = $4, revision = revision + 1
+		RETURNING "id", "revision", "data", "created_at", "updated_at"
+		`
+
+		now := time.Now().UTC()
+
+		args = []any{id, collection, JSONMap(document), now, now}
+
+		logger.Debug(
+			ctx, "executing query",
+			logger.F("query", query),
+			logger.F("args", args),
+		)
+
+		row = tx.QueryRowContext(ctx, query, args...)
+
 		var (
 			createdAt time.Time
 			updatedAt time.Time
 			data      JSONMap
 		)
 
-		err := row.Scan(&id, &data, &createdAt, &updatedAt)
-		if err != nil {
+		if err := row.Scan(&id, &revision, &data, &createdAt, &updatedAt); err != nil {
 			return errors.WithStack(err)
 		}
 
@@ -249,6 +282,7 @@ func (s *DocumentStore) Upsert(ctx context.Context, collection string, document
 		upsertedDocument = storage.Document(data)
 
 		upsertedDocument[storage.DocumentAttrID] = id
+		upsertedDocument[storage.DocumentAttrRevision] = revision
 		upsertedDocument[storage.DocumentAttrCreatedAt] = createdAt
 		upsertedDocument[storage.DocumentAttrUpdatedAt] = updatedAt
 
@@ -276,29 +310,13 @@ func (s *DocumentStore) withTx(ctx context.Context, fn func(tx *sql.Tx) error) e
 	return nil
 }
 
-func ensureDocumentTables(ctx context.Context, db *sql.DB) error {
+func migrateSchema(ctx context.Context, db *sql.DB) error {
 	err := WithTx(ctx, db, func(tx *sql.Tx) error {
-		query := `
-			CREATE TABLE IF NOT EXISTS documents (
-				id TEXT PRIMARY KEY,
-				collection TEXT NOT NULL,
-				data TEXT,
-				created_at TIMESTAMP NOT NULL,
-				updated_at TIMESTAMP NOT NULL,
-				UNIQUE(id, collection) ON CONFLICT REPLACE
-			);
-		`
-		if _, err := tx.ExecContext(ctx, query); err != nil {
-			return errors.WithStack(err)
+		for _, migr := range documentStoreMigrations {
+			if err := migr(ctx, tx); err != nil {
+				return errors.WithStack(err)
+			}
 		}
-
-		query = `
-			CREATE INDEX IF NOT EXISTS collection_idx ON documents (collection);
-		`
-		if _, err := tx.ExecContext(ctx, query); err != nil {
-			return errors.WithStack(err)
-		}
-
 		return nil
 	})
 	if err != nil {
@@ -344,7 +362,7 @@ func withLimitOffsetClause(query string, args []any, limit int, offset int) (str
 }
 
 func NewDocumentStore(path string) *DocumentStore {
-	getDB := NewGetDBFunc(path, ensureDocumentTables)
+	getDB := NewGetDBFunc(path, migrateSchema)
 
 	return &DocumentStore{
 		getDB: getDB,
@@ -352,7 +370,7 @@ func NewDocumentStore(path string) *DocumentStore {
 }
 
 func NewDocumentStoreWithDB(db *sql.DB) *DocumentStore {
-	getDB := NewGetDBFuncFromDB(db, ensureDocumentTables)
+	getDB := NewGetDBFuncFromDB(db, migrateSchema)
 
 	return &DocumentStore{
 		getDB: getDB,

pkg/storage/driver/sqlite/document_store.sql

@@ -0,0 +1,16 @@
+CREATE TABLE IF NOT EXISTS documents (
+    id TEXT PRIMARY KEY,
+    collection TEXT NOT NULL,
+    data TEXT,
+    created_at TIMESTAMP NOT NULL,
+    updated_at TIMESTAMP NOT NULL,
+    UNIQUE(id, collection) ON CONFLICT REPLACE
+);
+
+---
+
+CREATE INDEX IF NOT EXISTS collection_idx ON documents (collection);
+
+---
+
+ALTER TABLE documents ADD COLUMN revision INTEGER DEFAULT 0;

pkg/storage/driver/sqlite/document_store_migrations.go

@@ -0,0 +1,98 @@
+package sqlite
+
+import (
+	"context"
+	"database/sql"
+
+	"github.com/pkg/errors"
+	"gitlab.com/wpetit/goweb/logger"
+)
+
+type MigrateFunc func(ctx context.Context, tx *sql.Tx) error
+
+var documentStoreMigrations = []MigrateFunc{
+	documentStoreMigrationBaseSchema,
+	documentStoreMigrationAddIDIndex,
+	documentStoreMigrationAddRevisionColumn,
+}
+
+func documentStoreMigrationBaseSchema(ctx context.Context, tx *sql.Tx) error {
+	query := `
+		CREATE TABLE IF NOT EXISTS documents (
+			id TEXT PRIMARY KEY,
+			collection TEXT NOT NULL,
+			data TEXT,
+			created_at TIMESTAMP NOT NULL,
+			updated_at TIMESTAMP NOT NULL,
+			UNIQUE(id, collection) ON CONFLICT REPLACE
+		);
+	`
+
+	if _, err := tx.ExecContext(ctx, query); err != nil {
+		return errors.WithStack(err)
+	}
+
+	return nil
+}
+
+func documentStoreMigrationAddIDIndex(ctx context.Context, tx *sql.Tx) error {
+	query := `
+		CREATE INDEX IF NOT EXISTS collection_idx ON documents (collection);
+	`
+
+	if _, err := tx.ExecContext(ctx, query); err != nil {
+		return errors.WithStack(err)
+	}
+
+	return nil
+}
+
+func documentStoreMigrationAddRevisionColumn(ctx context.Context, tx *sql.Tx) error {
+	query := `PRAGMA table_info(documents)`
+
+	rows, err := tx.QueryContext(ctx, query)
+	if err != nil {
+		return errors.WithStack(err)
+	}
+
+	defer func() {
+		if err := rows.Close(); err != nil {
+			logger.Error(ctx, "could not close rows", logger.CapturedE(errors.WithStack(err)))
+		}
+	}()
+
+	var hasRevisionColumn bool
+
+	for rows.Next() {
+		var (
+			id           int
+			name         string
+			dataType     string
+			nullable     int
+			defaultValue any
+			primaryKey   int
+		)
+
+		if err := rows.Scan(&id, &name, &dataType, &nullable, &defaultValue, &primaryKey); err != nil {
+			return errors.WithStack(err)
+		}
+
+		if name == "revision" {
+			hasRevisionColumn = true
+			break
+		}
+	}
+
+	if err := rows.Err(); err != nil {
+		return errors.WithStack(err)
+	}
+
+	if !hasRevisionColumn {
+		query = `ALTER TABLE documents ADD COLUMN revision INTEGER DEFAULT 0`
+		if _, err := tx.ExecContext(ctx, query); err != nil {
+			return errors.WithStack(err)
+		}
+	}
+
+	return nil
+}

pkg/storage/driver/sqlite/document_store_test.go

@@ -22,7 +22,7 @@ func TestDocumentStore(t *testing.T) {
 		t.Fatalf("%+v", errors.WithStack(err))
 	}
 
-	dsn := fmt.Sprintf("%s?_pragma=foreign_keys(1)&_pragma=busy_timeout=%d", file, (60 * time.Second).Milliseconds())
+	dsn := fmt.Sprintf("%s?_pragma=foreign_keys(1)&_pragma=busy_timeout=%d&_pragma=journal_mode=wal", file, (60 * time.Second).Milliseconds())
 	store := NewDocumentStore(dsn)
 
 	testsuite.TestDocumentStore(context.Background(), t, store)

pkg/storage/driver/sqlite/driver.go

@@ -20,7 +20,7 @@ func init() {
 func documentStoreFactory(url *url.URL) (storage.DocumentStore, error) {
 	dir := filepath.Dir(url.Host + url.Path)
 
-	if dir != ":memory:" {
+	if dir != "." {
 		if err := os.MkdirAll(dir, os.FileMode(0750)); err != nil {
 			return nil, errors.WithStack(err)
 		}
@@ -39,7 +39,7 @@ func documentStoreFactory(url *url.URL) (storage.DocumentStore, error) {
 func blobStoreFactory(url *url.URL) (storage.BlobStore, error) {
 	dir := filepath.Dir(url.Host + url.Path)
 
-	if dir != ":memory:" {
+	if dir != "." {
 		if err := os.MkdirAll(dir, os.FileMode(0750)); err != nil {
 			return nil, errors.WithStack(err)
 		}
@@ -58,7 +58,7 @@ func blobStoreFactory(url *url.URL) (storage.BlobStore, error) {
 func shareStoreFactory(url *url.URL) (share.Store, error) {
 	dir := filepath.Dir(url.Host + url.Path)
 
-	if dir != ":memory:" {
+	if dir != "." {
 		if err := os.MkdirAll(dir, os.FileMode(0750)); err != nil {
 			return nil, errors.WithStack(err)
 		}

pkg/storage/driver/sqlite/share_store_test.go

@@ -26,7 +26,7 @@ func newTestStore(testName string) (share.Store, error) {
 		return nil, errors.WithStack(err)
 	}
 
-	dsn := fmt.Sprintf("%s?_pragma=foreign_keys(1)&_pragma=busy_timeout=%d", file, (60 * time.Second).Milliseconds())
+	dsn := fmt.Sprintf("%s?_pragma=foreign_keys(1)&_pragma=busy_timeout=%d&_pragma=journal_mode=wal", file, (60 * time.Second).Milliseconds())
 	store := NewShareStore(dsn)
 
 	return store, nil

pkg/storage/testsuite/document_store_ops.go

@@ -185,8 +185,13 @@ var documentStoreOpsTestCases = []documentStoreOpsTestCase{
 				return errors.Errorf("upsertedDoc[\"attr1\"]: expected '%v', got '%v'", e, g)
 			}
 
+			upsertedDocRevision, _ := upsertedDoc.Revision()
+			if e, g := 0, upsertedDocRevision; e != g {
+				return errors.Errorf("upsertedDoc.Revision(): expected '%v', got '%v'", e, g)
+			}
+
 			// Check that document does not have unexpected properties
-			if e, g := 4, len(upsertedDoc); e != g {
+			if e, g := 5, len(upsertedDoc); e != g {
 				return errors.Errorf("len(upsertedDoc): expected '%v', got '%v'", e, g)
 			}
 
@@ -217,6 +222,11 @@ var documentStoreOpsTestCases = []documentStoreOpsTestCase{
 				return errors.New("upsertedDoc2.UpdatedAt() should have been different than upsertedDoc.UpdatedAt()")
 			}
 
+			upsertedDoc2Revision, _ := upsertedDoc2.Revision()
+			if e, g := 1, upsertedDoc2Revision; e != g {
+				return errors.Errorf("upsertedDoc.Revision(): expected '%v', got '%v'", e, g)
+			}
+
 			// Verify that there is no additional created document in the collection
 
 			results, err := store.Query(ctx, collection, nil)
@@ -228,6 +238,11 @@ var documentStoreOpsTestCases = []documentStoreOpsTestCase{
 				return errors.Errorf("len(results): expected '%v', got '%v'", e, g)
 			}
 
+			firstResultRevision, _ := results[0].Revision()
+			if e, g := 1, firstResultRevision; e != g {
+				return errors.Errorf("results[0].Revision(): expected '%v', got '%v'", e, g)
+			}
+
 			return nil
 		},
 	},
@@ -437,7 +452,6 @@ func testDocumentStoreOps(ctx context.Context, t *testing.T, store storage.Docum
 	for _, tc := range documentStoreOpsTestCases {
 		func(tc documentStoreOpsTestCase) {
 			t.Run(tc.Name, func(t *testing.T) {
-				t.Parallel()
 				if err := tc.Run(ctx, store); err != nil {
 					t.Errorf("%+v", errors.WithStack(err))
 				}