diff options
Diffstat (limited to 'src/pkg/json/encode.go')
| -rw-r--r-- | src/pkg/json/encode.go | 46 |
1 files changed, 41 insertions, 5 deletions
diff --git a/src/pkg/json/encode.go b/src/pkg/json/encode.go index 0fcc78aa8..26ce47039 100644 --- a/src/pkg/json/encode.go +++ b/src/pkg/json/encode.go @@ -7,12 +7,14 @@ package json import ( - "os" "bytes" + "encoding/base64" + "os" "reflect" "runtime" "sort" "strconv" + "unicode" "utf8" ) @@ -31,12 +33,14 @@ import ( // String values encode as JSON strings, with each invalid UTF-8 sequence // replaced by the encoding of the Unicode replacement character U+FFFD. // -// Array and slice values encode as JSON arrays. +// Array and slice values encode as JSON arrays, except that +// []byte encodes as a base64-encoded string. // // Struct values encode as JSON objects. Each struct field becomes // a member of the object. By default the object's key name is the -// struct field name. If the struct field has a tag, that tag will -// be used as the name instead. Only exported fields will be encoded. +// struct field name. If the struct field has a non-empty tag consisting +// of only Unicode letters, digits, and underscores, that tag will be used +// as the name instead. Only exported fields will be encoded. // // Map values encode as JSON objects. // The map's key type must be string; the object keys are used directly @@ -176,6 +180,8 @@ func (e *encodeState) error(err os.Error) { panic(err) } +var byteSliceType = reflect.Typeof([]byte(nil)) + func (e *encodeState) reflectValue(v reflect.Value) { if v == nil { e.WriteString("null") @@ -230,7 +236,7 @@ func (e *encodeState) reflectValue(v reflect.Value) { } else { e.WriteByte(',') } - if f.Tag != "" { + if isValidTag(f.Tag) { e.string(f.Tag) } else { e.string(f.Name) @@ -262,6 +268,24 @@ func (e *encodeState) reflectValue(v reflect.Value) { e.WriteByte('}') case reflect.ArrayOrSliceValue: + if v.Type() == byteSliceType { + e.WriteByte('"') + s := v.Interface().([]byte) + if len(s) < 1024 { + // for small buffers, using Encode directly is much faster. + dst := make([]byte, base64.StdEncoding.EncodedLen(len(s))) + base64.StdEncoding.Encode(dst, s) + e.Write(dst) + } else { + // for large buffers, avoid unnecessary extra temporary + // buffer space. + enc := base64.NewEncoder(base64.StdEncoding, e) + enc.Write(s) + enc.Close() + } + e.WriteByte('"') + break + } e.WriteByte('[') n := v.Len() for i := 0; i < n; i++ { @@ -285,6 +309,18 @@ func (e *encodeState) reflectValue(v reflect.Value) { return } +func isValidTag(s string) bool { + if s == "" { + return false + } + for _, c := range s { + if c != '_' && !unicode.IsLetter(c) && !unicode.IsDigit(c) { + return false + } + } + return true +} + // stringValues is a slice of reflect.Value holding *reflect.StringValue. // It implements the methods to sort by string. type stringValues []reflect.Value |