trying pack (goober) encoding

Author: grantnelson-wf

build/cache/cache.go

@@ -6,6 +6,7 @@ import (
 	"compress/gzip"
 	"crypto/sha256"
 	"encoding/gob"
+	"encoding/json"
 	"fmt"
 	"go/build"
 	"io"
@@ -14,6 +15,7 @@ import (
 	"path/filepath"
 	"time"
 
+	"github.com/gopherjs/gopherjs/build/cache/pack"
 	log "github.com/sirupsen/logrus"
 )
 
@@ -26,6 +28,8 @@ import (
 type Cacheable interface {
 	Write(encode func(any) error) error
 	Read(decode func(any) error) error
+	PackEncode(e *pack.Encoder) error
+	PackDecode(d *pack.Decoder) error
 }
 
 // Cache defines methods to store and load cacheable objects.
@@ -206,23 +210,54 @@ func (bc *BuildCache) Load(c Cacheable, importPath string, srcModTime time.Time)
 	return true
 }
 
-func (bc *BuildCache) serialize(c Cacheable, buildTime time.Time, w io.Writer) (err error) {
+var encoding = `json`
+
+func (bc *BuildCache) serialize(c Cacheable, buildTime time.Time, w io.Writer) error {
+	switch encoding {
+	case `json`:
+		return bc.jsonSerialize(c, buildTime, w)
+	case `gob`:
+		return bc.gobSerialize(c, buildTime, w)
+	case `zipGob`:
+		return bc.zipGobSerialize(c, buildTime, w)
+	default:
+		panic(fmt.Errorf(`unknown encoding for serialization: %q`, encoding))
+	}
+}
+
+func (bc *BuildCache) deserialize(c Cacheable, srcModTime time.Time, r io.Reader) (buildTime time.Time, old bool, err error) {
+	switch encoding {
+	case `json`:
+		return bc.jsonDeserialize(c, srcModTime, r)
+	case `gob`:
+		return bc.gobDeserialize(c, srcModTime, r)
+	case `zipGob`:
+		return bc.zipGobDeserialize(c, srcModTime, r)
+	default:
+		panic(fmt.Errorf(`unknown encoding for serialization: %q`, encoding))
+	}
+}
+
+func (bc *BuildCache) zipGobSerialize(c Cacheable, buildTime time.Time, w io.Writer) (err error) {
 	zw := gzip.NewWriter(w)
 	defer func() {
 		// This close flushes the gzip but does not close the given writer.
 		if closeErr := zw.Close(); err == nil {
 			err = closeErr
 		}
 	}()
+	return bc.gobSerialize(c, buildTime, zw)
+}
 
-	ge := gob.NewEncoder(zw)
+func (bc *BuildCache) gobSerialize(c Cacheable, buildTime time.Time, w io.Writer) error {
+	ge := gob.NewEncoder(w)
 	if err := ge.Encode(buildTime); err != nil {
 		return err
 	}
 	return c.Write(ge.Encode)
 }
 
-func (bc *BuildCache) deserialize(c Cacheable, srcModTime time.Time, r io.Reader) (buildTime time.Time, old bool, err error) {
+func (bc *BuildCache) zipGobDeserialize(c Cacheable, srcModTime time.Time, r io.Reader) (buildTime time.Time, old bool, err error) {
 	zr, err := gzip.NewReader(r)
 	if err != nil {
 		return buildTime, false, err
@@ -233,8 +268,11 @@ func (bc *BuildCache) deserialize(c Cacheable, srcModTime time.Time, r io.Reader
 			err = closeErr
 		}
 	}()
+	return bc.gobDeserialize(c, srcModTime, zr)
+}
 
-	gd := gob.NewDecoder(zr)
+func (bc *BuildCache) gobDeserialize(c Cacheable, srcModTime time.Time, r io.Reader) (buildTime time.Time, old bool, err error) {
+	gd := gob.NewDecoder(r)
 	if err := gd.Decode(&buildTime); err != nil {
 		return buildTime, false, err
 	}
@@ -244,6 +282,25 @@ func (bc *BuildCache) deserialize(c Cacheable, srcModTime time.Time, r io.Reader
 	return buildTime, false, c.Read(gd.Decode)
 }
 
+func (bc *BuildCache) jsonSerialize(c Cacheable, buildTime time.Time, w io.Writer) (err error) {
+	encode := json.NewEncoder(w).Encode
+	if err := encode(&buildTime); err != nil {
+		return err
+	}
+	return c.Write(encode)
+}
+
+func (bc *BuildCache) jsonDeserialize(c Cacheable, srcModTime time.Time, r io.Reader) (buildTime time.Time, old bool, err error) {
+	decode := json.NewDecoder(r).Decode
+	if err := decode(&buildTime); err != nil {
+		return buildTime, false, err
+	}
+	if srcModTime.After(buildTime) {
+		return buildTime, true, nil // Package is out-of-date, cache miss.
+	}
+	return buildTime, false, c.Read(decode)
+}
+
 // commonKey returns a part of the cache key common for all artifacts generated
 // under a given BuildCache configuration.
 func (bc *BuildCache) commonKey() string {

build/cache/cache_test.go

@@ -5,12 +5,15 @@ import (
 	"time"
 
 	"github.com/google/go-cmp/cmp"
+	"github.com/gopherjs/gopherjs/build/cache/pack"
 )
 
 type CacheableMock struct{ Data string }
 
 func (m *CacheableMock) Write(encode func(any) error) error { return encode(m.Data) }
 func (m *CacheableMock) Read(decode func(any) error) error  { return decode(&m.Data) }
+func (m *CacheableMock) PackEncode(e *pack.Encoder) error   { return e.EncodeString(m.Data) }
+func (m *CacheableMock) PackDecode(d *pack.Decoder) error   { return d.DecodeString(&m.Data) }
 
 func TestStore(t *testing.T) {
 	cacheForTest(t)