feat(storage): rpc driver client pooling and memory-constrained cache

driver

ref #20

go.mod

@@ -15,11 +15,13 @@ require (
 
 require (
 	cloud.google.com/go v0.75.0 // indirect
+	github.com/allegro/bigcache/v3 v3.1.0 // indirect
 	github.com/decred/dcrd/dcrec/secp256k1/v4 v4.1.0 // indirect
 	github.com/go-playground/locales v0.14.0 // indirect
 	github.com/go-playground/universal-translator v0.18.0 // indirect
 	github.com/goccy/go-json v0.9.11 // indirect
 	github.com/gogo/protobuf v0.0.0-20161014173244-50d1bd39ce4e // indirect
+	github.com/jackc/puddle/v2 v2.2.1 // indirect
 	github.com/leodido/go-urn v1.2.1 // indirect
 	github.com/lestrrat-go/blackmagic v1.0.1 // indirect
 	github.com/lestrrat-go/httpcc v1.0.1 // indirect
@@ -27,6 +29,7 @@ require (
 	github.com/lestrrat-go/iter v1.0.2 // indirect
 	github.com/lestrrat-go/option v1.0.0 // indirect
 	github.com/miekg/dns v1.1.53 // indirect
+	golang.org/x/sync v0.1.0 // indirect
 	google.golang.org/genproto v0.0.0-20210226172003-ab064af71705 // indirect
 	google.golang.org/grpc v1.35.0 // indirect
 	gopkg.in/go-playground/validator.v9 v9.29.1 // indirect

go.sum

@@ -53,6 +53,8 @@ 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=
@@ -206,6 +208,8 @@ 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/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=
 github.com/jstemmer/go-junit-report v0.0.0-20190106144839-af01ea7f8024/go.mod h1:6v2b51hI/fHJwM22ozAgKL4VKDeJcHhJFhtBdhmNjmU=
 github.com/jstemmer/go-junit-report v0.9.1/go.mod h1:Brl9GWCQeLvo8nXZwPNNblvFj/XSXhF0NWZEnDohbsk=

pkg/storage/driver/cache/blob_bucket.go

@@ -6,14 +6,14 @@ import (
 	"io"
 
 	"forge.cadoles.com/arcad/edge/pkg/storage"
-	"github.com/hashicorp/golang-lru/v2/expirable"
+	"github.com/allegro/bigcache/v3"
 	"github.com/pkg/errors"
 	"gitlab.com/wpetit/goweb/logger"
 )
 
 type BlobBucket struct {
 	bucket storage.BlobBucket
-	cache  *expirable.LRU[string, []byte]
+	cache  *bigcache.BigCache
 }
 
 // Close implements storage.BlobBucket.
@@ -62,7 +62,7 @@ func (b *BlobBucket) Name() string {
 // NewReader implements storage.BlobBucket.
 func (b *BlobBucket) NewReader(ctx context.Context, id storage.BlobID) (io.ReadSeekCloser, error) {
 	if cached, exist := b.inCache(id); exist {
-		logger.Debug(ctx, "found blob in cache", logger.F("cacheKey", b.getCacheKey(id)))
+		logger.Debug(ctx, "found blob in cache", logger.F("cacheKey", b.getCacheKey(id)), logger.F("cacheStats", b.cache.Stats()))
 		return cached, nil
 	}
 
@@ -84,8 +84,14 @@ func (b *BlobBucket) getCacheKey(id storage.BlobID) string {
 
 func (b *BlobBucket) inCache(id storage.BlobID) (io.ReadSeekCloser, bool) {
 	key := b.getCacheKey(id)
-	data, exist := b.cache.Get(key)
+	data, err := b.cache.Get(key)
-	if !exist {
+	if err != nil {
+		if errors.Is(err, bigcache.ErrEntryNotFound) {
+			return nil, false
+		}
+
+		logger.Error(context.Background(), "could not retrieve cache value", logger.CapturedE(errors.WithStack(err)))
+
 		return nil, false
 	}
 

pkg/storage/driver/cache/blob_store.go

@@ -2,16 +2,15 @@ package cache
 
 import (
 	"context"
-	"time"
 
 	"forge.cadoles.com/arcad/edge/pkg/storage"
-	"github.com/hashicorp/golang-lru/v2/expirable"
+	"github.com/allegro/bigcache/v3"
 	"github.com/pkg/errors"
 )
 
 type BlobStore struct {
 	store storage.BlobStore
-	cache *expirable.LRU[string, []byte]
+	cache *bigcache.BigCache
 }
 
 // DeleteBucket implements storage.BlobStore.
@@ -46,10 +45,10 @@ func (s *BlobStore) OpenBucket(ctx context.Context, name string) (storage.BlobBu
 	}, nil
 }
 
-func NewBlobStore(store storage.BlobStore, cacheSize int, cacheTTL time.Duration) *BlobStore {
+func NewBlobStore(store storage.BlobStore, cache *bigcache.BigCache) *BlobStore {
 	return &BlobStore{
 		store: store,
-		cache: expirable.NewLRU[string, []byte](cacheSize, nil, cacheTTL),
+		cache: cache,
 	}
 }
 

pkg/storage/driver/cache/blob_store_test.go

@@ -9,6 +9,7 @@ import (
 
 	"forge.cadoles.com/arcad/edge/pkg/storage/driver/sqlite"
 	"forge.cadoles.com/arcad/edge/pkg/storage/testsuite"
+	"github.com/allegro/bigcache/v3"
 	"github.com/pkg/errors"
 	"gitlab.com/wpetit/goweb/logger"
 )
@@ -28,7 +29,13 @@ func TestBlobStore(t *testing.T) {
 	dsn := fmt.Sprintf("%s?_pragma=foreign_keys(1)&_pragma=busy_timeout=%d", file, (60 * time.Second).Milliseconds())
 
 	backend := sqlite.NewBlobStore(dsn)
-	store := NewBlobStore(backend, 32, time.Second*1)
+
+	cache, err := bigcache.New(context.Background(), bigcache.DefaultConfig(time.Minute))
+	if err != nil {
+		t.Fatalf("%+v", errors.WithStack(err))
+	}
+
+	store := NewBlobStore(backend, cache)
 
 	testsuite.TestBlobStore(context.Background(), t, store)
 }
@@ -44,7 +51,13 @@ func BenchmarkBlobStore(t *testing.B) {
 
 	dsn := fmt.Sprintf("%s?_pragma=foreign_keys(1)&_pragma=busy_timeout=%d", file, (60 * time.Second).Milliseconds())
 	backend := sqlite.NewBlobStore(dsn)
-	store := NewBlobStore(backend, 32, time.Minute)
+
+	cache, err := bigcache.New(context.Background(), bigcache.DefaultConfig(time.Minute))
+	if err != nil {
+		t.Fatalf("%+v", errors.WithStack(err))
+	}
+
+	store := NewBlobStore(backend, cache)
 
 	testsuite.BenchmarkBlobStore(t, store)
 }

pkg/storage/driver/cache/driver.go

@@ -1,13 +1,17 @@
 package cache
 
 import (
+	"context"
+	"fmt"
 	"net/url"
 	"strconv"
 	"time"
 
 	"forge.cadoles.com/arcad/edge/pkg/storage"
 	"forge.cadoles.com/arcad/edge/pkg/storage/driver"
+	"github.com/allegro/bigcache/v3"
 	"github.com/pkg/errors"
+	"gitlab.com/wpetit/goweb/logger"
 )
 
 func init() {
@@ -17,30 +21,6 @@ func init() {
 func blobStoreFactory(dsn *url.URL) (storage.BlobStore, error) {
 	query := dsn.Query()
 
-	rawCacheSize := query.Get("cacheSize")
-	if rawCacheSize == "" {
-		rawCacheSize = "128"
-	}
-
-	cacheSize, err := strconv.ParseInt(rawCacheSize, 10, 32)
-	if err != nil {
-		return nil, errors.Wrap(err, "could not parse cacheSize url parameter")
-	}
-
-	query.Del("cacheSize")
-
-	rawCacheTTL := query.Get("cacheTTL")
-	if rawCacheTTL == "" {
-		rawCacheTTL = "10m"
-	}
-
-	cacheTTL, err := time.ParseDuration(rawCacheTTL)
-	if err != nil {
-		return nil, errors.Wrap(err, "could not parse cacheTTL url parameter")
-	}
-
-	query.Del("cacheTTL")
-
 	rawDriver := query.Get("driver")
 	if rawDriver == "" {
 		return nil, errors.New("missing required url parameter 'driver'")
@@ -48,6 +28,54 @@ func blobStoreFactory(dsn *url.URL) (storage.BlobStore, error) {
 
 	query.Del("driver")
 
+	cacheTTL := time.Minute * 60
+
+	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 = ttl
+	}
+
+	cacheConfig := bigcache.DefaultConfig(cacheTTL)
+	cacheConfig.Logger = &cacheLogger{}
+
+	rawCacheShards := query.Get("cacheShards")
+	if rawCacheShards != "" {
+		query.Del("cacheShards")
+
+		cacheShards, err := strconv.ParseInt(rawCacheShards, 10, 32)
+		if err != nil {
+			return nil, errors.Wrap(err, "could not parse url parameter 'cacheShards'")
+		}
+
+		cacheConfig.Shards = int(cacheShards)
+	}
+
+	rawMaxCacheSize := query.Get("maxCacheSize")
+	if rawMaxCacheSize != "" {
+		query.Del("maxCacheSize")
+
+		maxCacheSize, err := strconv.ParseInt(rawMaxCacheSize, 10, 32)
+		if err != nil {
+			return nil, errors.Wrap(err, "could not parse url parameter 'maxCacheSize'")
+		}
+
+		// See cacheConfig.HardMaxCacheSize documentation
+		var minCacheSize int64 = (2 * (64 + 32) * int64(cacheConfig.Shards)) / 1000
+
+		if maxCacheSize < minCacheSize {
+			return nil, errors.Errorf("max cache size can not be set to a value below '%d'", minCacheSize)
+		}
+
+		cacheConfig.HardMaxCacheSize = int(maxCacheSize)
+	}
+
 	url := &url.URL{
 		Scheme:   rawDriver,
 		Host:     dsn.Host,
@@ -60,5 +88,18 @@ func blobStoreFactory(dsn *url.URL) (storage.BlobStore, error) {
 		return nil, errors.WithStack(err)
 	}
 
-	return NewBlobStore(store, int(cacheSize), cacheTTL), nil
+	cache, err := bigcache.New(context.Background(), cacheConfig)
+	if err != nil {
+		return nil, errors.WithStack(err)
 	}
+
+	return NewBlobStore(store, cache), nil
+}
+
+type cacheLogger struct{}
+
+func (l *cacheLogger) Printf(format string, v ...interface{}) {
+	logger.Debug(context.Background(), fmt.Sprintf(format, v...))
+}
+
+var _ bigcache.Logger = &cacheLogger{}

pkg/storage/driver/cache/reader.go

@@ -1,21 +1,19 @@
 package cache
 
 import (
-	"bytes"
 	"context"
 	"fmt"
 	"io"
 
-	"github.com/hashicorp/golang-lru/v2/expirable"
+	"github.com/allegro/bigcache/v3"
 	"github.com/pkg/errors"
 	"gitlab.com/wpetit/goweb/logger"
 )
 
 type readCacher struct {
 	reader io.ReadSeekCloser
-	cache  *expirable.LRU[string, []byte]
+	cache  *bigcache.BigCache
 	key    string
-	buffer bytes.Buffer
 }
 
 // Close implements io.ReadSeekCloser.
@@ -32,16 +30,6 @@ func (r *readCacher) Read(p []byte) (n int, err error) {
 	length, err := r.reader.Read(p)
 	if err != nil {
 		if err == io.EOF {
-			if length > 0 {
-				if _, err := r.buffer.Write(p[:length]); err != nil {
-					logger.Error(context.Background(), "could not write to buffer", logger.CapturedE(errors.WithStack(err)))
-					return length, io.EOF
-				}
-			}
-
-			logger.Debug(context.Background(), "caching blob", logger.F("cacheKey", r.key))
-			r.cache.Add(r.key, r.buffer.Bytes())
-
 			return length, io.EOF
 		}
 
@@ -49,8 +37,13 @@ func (r *readCacher) Read(p []byte) (n int, err error) {
 	}
 
 	if length > 0 {
-		if _, err := r.buffer.Write(p[:length]); err != nil {
+		if err := r.cache.Append(r.key, p[:length]); err != nil {
-			logger.Error(context.Background(), "could not write to buffer", logger.CapturedE(errors.WithStack(err)))
+			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/rpc/client/blob_store.go

@@ -5,7 +5,6 @@ import (
 	"net/url"
 
 	"github.com/keegancsmith/rpc"
-	"gitlab.com/wpetit/goweb/logger"
 
 	"forge.cadoles.com/arcad/edge/pkg/storage"
 	"forge.cadoles.com/arcad/edge/pkg/storage/driver/rpc/server/blob"
@@ -13,7 +12,7 @@ import (
 )
 
 type BlobStore struct {
-	serverURL *url.URL
+	withClient WithClientFunc
 }
 
 // DeleteBucket implements storage.BlobStore.
@@ -75,27 +74,11 @@ func (s *BlobStore) call(ctx context.Context, serviceMethod string, args any, re
 	return nil
 }
 
-func (s *BlobStore) withClient(ctx context.Context, fn func(ctx context.Context, client *rpc.Client) error) error {
-	client, err := rpc.DialHTTPPath("tcp", s.serverURL.Host, s.serverURL.Path+"?"+s.serverURL.RawQuery)
-	if err != nil {
-		return errors.WithStack(err)
-	}
-
-	defer func() {
-		if err := client.Close(); err != nil {
-			logger.Error(ctx, "could not close rpc client", logger.CapturedE(errors.WithStack(err)))
-		}
-	}()
-
-	if err := fn(ctx, client); err != nil {
-		return errors.WithStack(err)
-	}
-
-	return nil
-}
-
 func NewBlobStore(serverURL *url.URL) *BlobStore {
-	return &BlobStore{serverURL}
+	withClient := WithPooledClient(serverURL)
+	return &BlobStore{
+		withClient: withClient,
+	}
 }
 
 var _ storage.BlobStore = &BlobStore{}

pkg/storage/driver/rpc/client/client_pool.go

@@ -0,0 +1,94 @@
+package client
+
+import (
+	"context"
+	"net/url"
+	"strconv"
+	"sync"
+
+	"github.com/jackc/puddle/v2"
+	"github.com/keegancsmith/rpc"
+	"github.com/pkg/errors"
+	"gitlab.com/wpetit/goweb/logger"
+)
+
+func NewClientPool(serverURL *url.URL, poolSize int) (*puddle.Pool[*rpc.Client], error) {
+	constructor := func(context.Context) (*rpc.Client, error) {
+		client, err := rpc.DialHTTPPath("tcp", serverURL.Host, serverURL.Path+"?"+serverURL.RawQuery)
+		if err != nil {
+			return nil, errors.WithStack(err)
+		}
+
+		return client, nil
+	}
+
+	destructor := func(client *rpc.Client) {
+		if err := client.Close(); err != nil {
+			logger.Error(context.Background(), "could not close client", logger.CapturedE(errors.WithStack(err)))
+		}
+	}
+
+	maxPoolSize := int32(poolSize)
+
+	pool, err := puddle.NewPool(&puddle.Config[*rpc.Client]{Constructor: constructor, Destructor: destructor, MaxSize: maxPoolSize})
+	if err != nil {
+		return nil, errors.WithStack(err)
+	}
+
+	return pool, nil
+}
+
+type WithClientFunc func(ctx context.Context, fn func(ctx context.Context, client *rpc.Client) error) error
+
+func WithPooledClient(serverURL *url.URL) WithClientFunc {
+	var (
+		pool       *puddle.Pool[*rpc.Client]
+		createPool sync.Once
+	)
+
+	return func(ctx context.Context, fn func(context.Context, *rpc.Client) error) error {
+		var err error
+		createPool.Do(func() {
+			rawPoolSize := serverURL.Query().Get("clientPoolSize")
+			if rawPoolSize == "" {
+				rawPoolSize = "5"
+			}
+
+			var poolSize int64
+
+			poolSize, err = strconv.ParseInt(rawPoolSize, 10, 32)
+			if err != nil {
+				err = errors.Wrap(err, "could not parse clientPoolSize url query parameter")
+
+				return
+			}
+
+			pool, err = NewClientPool(serverURL, int(poolSize))
+			if err != nil {
+				err = errors.WithStack(err)
+
+				return
+			}
+		})
+		if err != nil {
+			return errors.WithStack(err)
+		}
+
+		clientResource, err := pool.Acquire(ctx)
+		if err != nil {
+			return errors.WithStack(err)
+		}
+
+		if err := fn(ctx, clientResource.Value()); err != nil {
+			if errors.Is(err, rpc.ErrShutdown) {
+				clientResource.Destroy()
+			}
+
+			return errors.WithStack(err)
+		}
+
+		clientResource.Release()
+
+		return nil
+	}
+}

pkg/storage/driver/rpc/client/document_store.go

@@ -6,7 +6,6 @@ import (
 
 	"github.com/keegancsmith/rpc"
 	"github.com/pkg/errors"
-	"gitlab.com/wpetit/goweb/logger"
 
 	"forge.cadoles.com/arcad/edge/pkg/storage"
 	"forge.cadoles.com/arcad/edge/pkg/storage/driver/rpc/server/document"
@@ -14,7 +13,7 @@ import (
 )
 
 type DocumentStore struct {
-	serverURL *url.URL
+	withClient WithClientFunc
 }
 
 // Delete implements storage.DocumentStore.
@@ -108,27 +107,12 @@ func (s *DocumentStore) call(ctx context.Context, serviceMethod string, args any
 	return nil
 }
 
-func (s *DocumentStore) withClient(ctx context.Context, fn func(ctx context.Context, client *rpc.Client) error) error {
+func NewDocumentStore(serverURL *url.URL) *DocumentStore {
-	client, err := rpc.DialHTTPPath("tcp", s.serverURL.Host, s.serverURL.Path+"?"+s.serverURL.RawQuery)
+	withClient := WithPooledClient(serverURL)
-	if err != nil {
-		return errors.WithStack(err)
-	}
 
-	defer func() {
+	return &DocumentStore{
-		if err := client.Close(); err != nil {
+		withClient: withClient,
-			logger.Error(ctx, "could not close rpc client", logger.CapturedE(errors.WithStack(err)))
 	}
-	}()
-
-	if err := fn(ctx, client); err != nil {
-		return errors.WithStack(err)
-	}
-
-	return nil
-}
-
-func NewDocumentStore(url *url.URL) *DocumentStore {
-	return &DocumentStore{url}
 }
 
 var _ storage.DocumentStore = &DocumentStore{}