super-graph/core/internal/allow/allow.go

358 lines
6.3 KiB
Go

package allow
import (
"bytes"
"encoding/json"
"errors"
"fmt"
"io/ioutil"
"log"
"os"
"sort"
"strings"
"text/scanner"
"github.com/chirino/graphql/schema"
"github.com/dosco/super-graph/jsn"
)
const (
expComment = iota + 1
expVar
expQuery
)
type Item struct {
Name string
key string
Query string
Vars string
Comment string
}
type List struct {
filepath string
saveChan chan Item
}
type Config struct {
CreateIfNotExists bool
Persist bool
Log *log.Logger
}
func New(filename string, conf Config) (*List, error) {
al := List{}
if filename != "" {
fp := filename
if _, err := os.Stat(fp); err == nil {
al.filepath = fp
} else if !os.IsNotExist(err) {
return nil, err
}
}
if al.filepath == "" {
fp := "./allow.list"
if _, err := os.Stat(fp); err == nil {
al.filepath = fp
} else if !os.IsNotExist(err) {
return nil, err
}
}
if al.filepath == "" {
fp := "./config/allow.list"
if _, err := os.Stat(fp); err == nil {
al.filepath = fp
} else if !os.IsNotExist(err) {
return nil, err
}
}
if al.filepath == "" {
if !conf.CreateIfNotExists {
return nil, errors.New("allow.list not found")
}
if filename == "" {
al.filepath = "./config/allow.list"
} else {
al.filepath = filename
}
if file, err := os.OpenFile(al.filepath, os.O_RDONLY|os.O_CREATE, 0644); err != nil {
return nil, err
} else {
file.Close()
}
}
var err error
if conf.Persist {
al.saveChan = make(chan Item)
go func() {
for v := range al.saveChan {
err := al.save(v)
if err != nil && conf.Log != nil {
conf.Log.Println("WRN allow list save:", err)
}
}
}()
}
if err != nil {
return nil, err
}
return &al, nil
}
func (al *List) IsPersist() bool {
return al.saveChan != nil
}
func (al *List) Set(vars []byte, query, comment string) error {
if al.saveChan == nil {
return errors.New("allow.list is read-only")
}
if query == "" {
return errors.New("empty query")
}
al.saveChan <- Item{
Comment: comment,
Query: query,
Vars: string(vars),
}
return nil
}
func (al *List) Load() ([]Item, error) {
b, err := ioutil.ReadFile(al.filepath)
if err != nil {
return nil, err
}
return parse(string(b), al.filepath)
}
func parse(b string, filename string) ([]Item, error) {
var items []Item
var s scanner.Scanner
s.Init(strings.NewReader(b))
s.Filename = filename
s.Mode ^= scanner.SkipComments
var op, sp scanner.Position
var item Item
newComment := false
st := expComment
for tok := s.Scan(); tok != scanner.EOF; tok = s.Scan() {
txt := s.TokenText()
switch {
case strings.HasPrefix(txt, "/*"):
if st == expQuery {
v := b[sp.Offset:s.Pos().Offset]
item.Query = strings.TrimSpace(v[:strings.LastIndexByte(v, '}')+1])
items = append(items, item)
}
item = Item{Comment: strings.TrimSpace(txt[2 : len(txt)-2])}
sp = s.Pos()
st = expComment
newComment = true
case !newComment && strings.HasPrefix(txt, "#"):
if st == expQuery {
v := b[sp.Offset:s.Pos().Offset]
item.Query = strings.TrimSpace(v[:strings.LastIndexByte(v, '}')+1])
items = append(items, item)
}
item = Item{}
sp = s.Pos()
st = expComment
case strings.HasPrefix(txt, "variables"):
if st == expComment {
v := b[sp.Offset:s.Pos().Offset]
item.Comment = strings.TrimSpace(v[:strings.IndexByte(v, '\n')])
}
sp = s.Pos()
st = expVar
case isGraphQL(txt):
if st == expVar {
v := b[sp.Offset:s.Pos().Offset]
item.Vars = strings.TrimSpace(v[:strings.LastIndexByte(v, '}')+1])
}
sp = op
st = expQuery
}
op = s.Pos()
}
if st == expQuery {
v := b[sp.Offset:s.Pos().Offset]
item.Query = strings.TrimSpace(v[:strings.LastIndexByte(v, '}')+1])
items = append(items, item)
}
for i := range items {
items[i].Name = QueryName(items[i].Query)
items[i].key = strings.ToLower(items[i].Name)
}
return items, nil
}
func isGraphQL(s string) bool {
return strings.HasPrefix(s, "query") ||
strings.HasPrefix(s, "mutation") ||
strings.HasPrefix(s, "subscription")
}
func (al *List) save(item Item) error {
var buf bytes.Buffer
qd := &schema.QueryDocument{}
if err := qd.Parse(item.Query); err != nil {
return err
}
qd.WriteTo(&buf)
query := buf.String()
buf.Reset()
item.Name = QueryName(query)
item.key = strings.ToLower(item.Name)
if item.Name == "" {
return nil
}
list, err := al.Load()
if err != nil {
return err
}
index := -1
for i, v := range list {
if strings.EqualFold(v.Name, item.Name) {
index = i
break
}
}
if index != -1 {
if list[index].Comment != "" {
item.Comment = list[index].Comment
}
list[index] = item
} else {
list = append(list, item)
}
f, err := os.Create(al.filepath)
if err != nil {
return err
}
defer f.Close()
sort.Slice(list, func(i, j int) bool {
return strings.Compare(list[i].key, list[j].key) == -1
})
for i, v := range list {
var vars string
if v.Vars != "" {
buf.Reset()
if err := jsn.Clear(&buf, []byte(v.Vars)); err != nil {
continue
}
vj := json.RawMessage(buf.Bytes())
if vj, err = json.MarshalIndent(vj, "", " "); err != nil {
continue
}
vars = string(vj)
}
list[i].Vars = vars
list[i].Comment = strings.TrimSpace(v.Comment)
}
for _, v := range list {
if v.Comment != "" {
f.WriteString(fmt.Sprintf("/* %s */\n\n", v.Comment))
} else {
f.WriteString(fmt.Sprintf("/* %s */\n\n", v.Name))
}
if v.Vars != "" {
_, err = f.WriteString(fmt.Sprintf("variables %s\n\n", v.Vars))
if err != nil {
return err
}
}
_, err = f.WriteString(fmt.Sprintf("%s\n\n", v.Query))
if err != nil {
return err
}
}
return nil
}
func matchPrefix(b []byte, i int, s string) bool {
if (len(b) - i) < len(s) {
return false
}
for n := 0; n < len(s); n++ {
if b[(i+n)] != s[n] {
return false
}
}
return true
}
func QueryName(b string) string {
state, s := 0, 0
for i := 0; i < len(b); i++ {
switch {
case state == 2 && !isValidNameChar(b[i]):
return b[s:i]
case state == 1 && b[i] == '{':
return ""
case state == 1 && isValidNameChar(b[i]):
s = i
state = 2
case i != 0 && b[i] == ' ' && (b[i-1] == 'n' || b[i-1] == 'y'):
state = 1
}
}
return ""
}
func isValidNameChar(c byte) bool {
return (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9') || c == '_'
}