diff options
Diffstat (limited to 'vendor/github.com/aws/aws-sdk-go/private/protocol/json/jsonutil/build.go')
-rw-r--r-- | vendor/github.com/aws/aws-sdk-go/private/protocol/json/jsonutil/build.go | 296 |
1 files changed, 296 insertions, 0 deletions
diff --git a/vendor/github.com/aws/aws-sdk-go/private/protocol/json/jsonutil/build.go b/vendor/github.com/aws/aws-sdk-go/private/protocol/json/jsonutil/build.go new file mode 100644 index 000000000..864fb6704 --- /dev/null +++ b/vendor/github.com/aws/aws-sdk-go/private/protocol/json/jsonutil/build.go @@ -0,0 +1,296 @@ +// Package jsonutil provides JSON serialization of AWS requests and responses. +package jsonutil + +import ( + "bytes" + "encoding/base64" + "encoding/json" + "fmt" + "math" + "reflect" + "sort" + "strconv" + "time" + + "github.com/aws/aws-sdk-go/aws" + "github.com/aws/aws-sdk-go/private/protocol" +) + +var timeType = reflect.ValueOf(time.Time{}).Type() +var byteSliceType = reflect.ValueOf([]byte{}).Type() + +// BuildJSON builds a JSON string for a given object v. +func BuildJSON(v interface{}) ([]byte, error) { + var buf bytes.Buffer + + err := buildAny(reflect.ValueOf(v), &buf, "") + return buf.Bytes(), err +} + +func buildAny(value reflect.Value, buf *bytes.Buffer, tag reflect.StructTag) error { + origVal := value + value = reflect.Indirect(value) + if !value.IsValid() { + return nil + } + + vtype := value.Type() + + t := tag.Get("type") + if t == "" { + switch vtype.Kind() { + case reflect.Struct: + // also it can't be a time object + if value.Type() != timeType { + t = "structure" + } + case reflect.Slice: + // also it can't be a byte slice + if _, ok := value.Interface().([]byte); !ok { + t = "list" + } + case reflect.Map: + // cannot be a JSONValue map + if _, ok := value.Interface().(aws.JSONValue); !ok { + t = "map" + } + } + } + + switch t { + case "structure": + if field, ok := vtype.FieldByName("_"); ok { + tag = field.Tag + } + return buildStruct(value, buf, tag) + case "list": + return buildList(value, buf, tag) + case "map": + return buildMap(value, buf, tag) + default: + return buildScalar(origVal, buf, tag) + } +} + +func buildStruct(value reflect.Value, buf *bytes.Buffer, tag reflect.StructTag) error { + if !value.IsValid() { + return nil + } + + // unwrap payloads + if payload := tag.Get("payload"); payload != "" { + field, _ := value.Type().FieldByName(payload) + tag = field.Tag + value = elemOf(value.FieldByName(payload)) + + if !value.IsValid() { + return nil + } + } + + buf.WriteByte('{') + + t := value.Type() + first := true + for i := 0; i < t.NumField(); i++ { + member := value.Field(i) + + // This allocates the most memory. + // Additionally, we cannot skip nil fields due to + // idempotency auto filling. + field := t.Field(i) + + if field.PkgPath != "" { + continue // ignore unexported fields + } + if field.Tag.Get("json") == "-" { + continue + } + if field.Tag.Get("location") != "" { + continue // ignore non-body elements + } + if field.Tag.Get("ignore") != "" { + continue + } + + if protocol.CanSetIdempotencyToken(member, field) { + token := protocol.GetIdempotencyToken() + member = reflect.ValueOf(&token) + } + + if (member.Kind() == reflect.Ptr || member.Kind() == reflect.Slice || member.Kind() == reflect.Map) && member.IsNil() { + continue // ignore unset fields + } + + if first { + first = false + } else { + buf.WriteByte(',') + } + + // figure out what this field is called + name := field.Name + if locName := field.Tag.Get("locationName"); locName != "" { + name = locName + } + + writeString(name, buf) + buf.WriteString(`:`) + + err := buildAny(member, buf, field.Tag) + if err != nil { + return err + } + + } + + buf.WriteString("}") + + return nil +} + +func buildList(value reflect.Value, buf *bytes.Buffer, tag reflect.StructTag) error { + buf.WriteString("[") + + for i := 0; i < value.Len(); i++ { + buildAny(value.Index(i), buf, "") + + if i < value.Len()-1 { + buf.WriteString(",") + } + } + + buf.WriteString("]") + + return nil +} + +type sortedValues []reflect.Value + +func (sv sortedValues) Len() int { return len(sv) } +func (sv sortedValues) Swap(i, j int) { sv[i], sv[j] = sv[j], sv[i] } +func (sv sortedValues) Less(i, j int) bool { return sv[i].String() < sv[j].String() } + +func buildMap(value reflect.Value, buf *bytes.Buffer, tag reflect.StructTag) error { + buf.WriteString("{") + + sv := sortedValues(value.MapKeys()) + sort.Sort(sv) + + for i, k := range sv { + if i > 0 { + buf.WriteByte(',') + } + + writeString(k.String(), buf) + buf.WriteString(`:`) + + buildAny(value.MapIndex(k), buf, "") + } + + buf.WriteString("}") + + return nil +} + +func buildScalar(v reflect.Value, buf *bytes.Buffer, tag reflect.StructTag) error { + // prevents allocation on the heap. + scratch := [64]byte{} + switch value := reflect.Indirect(v); value.Kind() { + case reflect.String: + writeString(value.String(), buf) + case reflect.Bool: + if value.Bool() { + buf.WriteString("true") + } else { + buf.WriteString("false") + } + case reflect.Int64: + buf.Write(strconv.AppendInt(scratch[:0], value.Int(), 10)) + case reflect.Float64: + f := value.Float() + if math.IsInf(f, 0) || math.IsNaN(f) { + return &json.UnsupportedValueError{Value: v, Str: strconv.FormatFloat(f, 'f', -1, 64)} + } + buf.Write(strconv.AppendFloat(scratch[:0], f, 'f', -1, 64)) + default: + switch converted := value.Interface().(type) { + case time.Time: + format := tag.Get("timestampFormat") + if len(format) == 0 { + format = protocol.UnixTimeFormatName + } + + ts := protocol.FormatTime(format, converted) + if format != protocol.UnixTimeFormatName { + ts = `"` + ts + `"` + } + + buf.WriteString(ts) + case []byte: + if !value.IsNil() { + buf.WriteByte('"') + if len(converted) < 1024 { + // for small buffers, using Encode directly is much faster. + dst := make([]byte, base64.StdEncoding.EncodedLen(len(converted))) + base64.StdEncoding.Encode(dst, converted) + buf.Write(dst) + } else { + // for large buffers, avoid unnecessary extra temporary + // buffer space. + enc := base64.NewEncoder(base64.StdEncoding, buf) + enc.Write(converted) + enc.Close() + } + buf.WriteByte('"') + } + case aws.JSONValue: + str, err := protocol.EncodeJSONValue(converted, protocol.QuotedEscape) + if err != nil { + return fmt.Errorf("unable to encode JSONValue, %v", err) + } + buf.WriteString(str) + default: + return fmt.Errorf("unsupported JSON value %v (%s)", value.Interface(), value.Type()) + } + } + return nil +} + +var hex = "0123456789abcdef" + +func writeString(s string, buf *bytes.Buffer) { + buf.WriteByte('"') + for i := 0; i < len(s); i++ { + if s[i] == '"' { + buf.WriteString(`\"`) + } else if s[i] == '\\' { + buf.WriteString(`\\`) + } else if s[i] == '\b' { + buf.WriteString(`\b`) + } else if s[i] == '\f' { + buf.WriteString(`\f`) + } else if s[i] == '\r' { + buf.WriteString(`\r`) + } else if s[i] == '\t' { + buf.WriteString(`\t`) + } else if s[i] == '\n' { + buf.WriteString(`\n`) + } else if s[i] < 32 { + buf.WriteString("\\u00") + buf.WriteByte(hex[s[i]>>4]) + buf.WriteByte(hex[s[i]&0xF]) + } else { + buf.WriteByte(s[i]) + } + } + buf.WriteByte('"') +} + +// Returns the reflection element of a value, if it is a pointer. +func elemOf(value reflect.Value) reflect.Value { + for value.Kind() == reflect.Ptr { + value = value.Elem() + } + return value +} |