xref: /aosp_15_r20/external/golang-protobuf/internal/msgfmt/format.go (revision 1c12ee1efe575feb122dbf939ff15148a3b3e8f2)
1// Copyright 2019 The Go Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style
3// license that can be found in the LICENSE file.
4
5// Package msgfmt implements a text marshaler combining the desirable features
6// of both the JSON and proto text formats.
7// It is optimized for human readability and has no associated deserializer.
8package msgfmt
9
10import (
11	"bytes"
12	"fmt"
13	"reflect"
14	"sort"
15	"strconv"
16	"strings"
17	"time"
18
19	"google.golang.org/protobuf/encoding/protowire"
20	"google.golang.org/protobuf/internal/detrand"
21	"google.golang.org/protobuf/internal/genid"
22	"google.golang.org/protobuf/internal/order"
23	"google.golang.org/protobuf/proto"
24	"google.golang.org/protobuf/reflect/protoreflect"
25	"google.golang.org/protobuf/reflect/protoregistry"
26)
27
28// Format returns a formatted string for the message.
29func Format(m proto.Message) string {
30	return string(appendMessage(nil, m.ProtoReflect()))
31}
32
33// FormatValue returns a formatted string for an arbitrary value.
34func FormatValue(v protoreflect.Value, fd protoreflect.FieldDescriptor) string {
35	return string(appendValue(nil, v, fd))
36}
37
38func appendValue(b []byte, v protoreflect.Value, fd protoreflect.FieldDescriptor) []byte {
39	switch v := v.Interface().(type) {
40	case nil:
41		return append(b, "<invalid>"...)
42	case bool, int32, int64, uint32, uint64, float32, float64:
43		return append(b, fmt.Sprint(v)...)
44	case string:
45		return append(b, strconv.Quote(string(v))...)
46	case []byte:
47		return append(b, strconv.Quote(string(v))...)
48	case protoreflect.EnumNumber:
49		return appendEnum(b, v, fd)
50	case protoreflect.Message:
51		return appendMessage(b, v)
52	case protoreflect.List:
53		return appendList(b, v, fd)
54	case protoreflect.Map:
55		return appendMap(b, v, fd)
56	default:
57		panic(fmt.Sprintf("invalid type: %T", v))
58	}
59}
60
61func appendEnum(b []byte, v protoreflect.EnumNumber, fd protoreflect.FieldDescriptor) []byte {
62	if fd != nil {
63		if ev := fd.Enum().Values().ByNumber(v); ev != nil {
64			return append(b, ev.Name()...)
65		}
66	}
67	return strconv.AppendInt(b, int64(v), 10)
68}
69
70func appendMessage(b []byte, m protoreflect.Message) []byte {
71	if b2 := appendKnownMessage(b, m); b2 != nil {
72		return b2
73	}
74
75	b = append(b, '{')
76	order.RangeFields(m, order.IndexNameFieldOrder, func(fd protoreflect.FieldDescriptor, v protoreflect.Value) bool {
77		b = append(b, fd.TextName()...)
78		b = append(b, ':')
79		b = appendValue(b, v, fd)
80		b = append(b, delim()...)
81		return true
82	})
83	b = appendUnknown(b, m.GetUnknown())
84	b = bytes.TrimRight(b, delim())
85	b = append(b, '}')
86	return b
87}
88
89var protocmpMessageType = reflect.TypeOf(map[string]interface{}(nil))
90
91func appendKnownMessage(b []byte, m protoreflect.Message) []byte {
92	md := m.Descriptor()
93	fds := md.Fields()
94	switch md.FullName() {
95	case genid.Any_message_fullname:
96		var msgVal protoreflect.Message
97		url := m.Get(fds.ByNumber(genid.Any_TypeUrl_field_number)).String()
98		if v := reflect.ValueOf(m); v.Type().ConvertibleTo(protocmpMessageType) {
99			// For protocmp.Message, directly obtain the sub-message value
100			// which is stored in structured form, rather than as raw bytes.
101			m2 := v.Convert(protocmpMessageType).Interface().(map[string]interface{})
102			v, ok := m2[string(genid.Any_Value_field_name)].(proto.Message)
103			if !ok {
104				return nil
105			}
106			msgVal = v.ProtoReflect()
107		} else {
108			val := m.Get(fds.ByNumber(genid.Any_Value_field_number)).Bytes()
109			mt, err := protoregistry.GlobalTypes.FindMessageByURL(url)
110			if err != nil {
111				return nil
112			}
113			msgVal = mt.New()
114			err = proto.UnmarshalOptions{AllowPartial: true}.Unmarshal(val, msgVal.Interface())
115			if err != nil {
116				return nil
117			}
118		}
119
120		b = append(b, '{')
121		b = append(b, "["+url+"]"...)
122		b = append(b, ':')
123		b = appendMessage(b, msgVal)
124		b = append(b, '}')
125		return b
126
127	case genid.Timestamp_message_fullname:
128		secs := m.Get(fds.ByNumber(genid.Timestamp_Seconds_field_number)).Int()
129		nanos := m.Get(fds.ByNumber(genid.Timestamp_Nanos_field_number)).Int()
130		if nanos < 0 || nanos >= 1e9 {
131			return nil
132		}
133		t := time.Unix(secs, nanos).UTC()
134		x := t.Format("2006-01-02T15:04:05.000000000") // RFC 3339
135		x = strings.TrimSuffix(x, "000")
136		x = strings.TrimSuffix(x, "000")
137		x = strings.TrimSuffix(x, ".000")
138		return append(b, x+"Z"...)
139
140	case genid.Duration_message_fullname:
141		sign := ""
142		secs := m.Get(fds.ByNumber(genid.Duration_Seconds_field_number)).Int()
143		nanos := m.Get(fds.ByNumber(genid.Duration_Nanos_field_number)).Int()
144		if nanos <= -1e9 || nanos >= 1e9 || (secs > 0 && nanos < 0) || (secs < 0 && nanos > 0) {
145			return nil
146		}
147		if secs < 0 || nanos < 0 {
148			sign, secs, nanos = "-", -1*secs, -1*nanos
149		}
150		x := fmt.Sprintf("%s%d.%09d", sign, secs, nanos)
151		x = strings.TrimSuffix(x, "000")
152		x = strings.TrimSuffix(x, "000")
153		x = strings.TrimSuffix(x, ".000")
154		return append(b, x+"s"...)
155
156	case genid.BoolValue_message_fullname,
157		genid.Int32Value_message_fullname,
158		genid.Int64Value_message_fullname,
159		genid.UInt32Value_message_fullname,
160		genid.UInt64Value_message_fullname,
161		genid.FloatValue_message_fullname,
162		genid.DoubleValue_message_fullname,
163		genid.StringValue_message_fullname,
164		genid.BytesValue_message_fullname:
165		fd := fds.ByNumber(genid.WrapperValue_Value_field_number)
166		return appendValue(b, m.Get(fd), fd)
167	}
168
169	return nil
170}
171
172func appendUnknown(b []byte, raw protoreflect.RawFields) []byte {
173	rs := make(map[protoreflect.FieldNumber][]protoreflect.RawFields)
174	for len(raw) > 0 {
175		num, _, n := protowire.ConsumeField(raw)
176		rs[num] = append(rs[num], raw[:n])
177		raw = raw[n:]
178	}
179
180	var ns []protoreflect.FieldNumber
181	for n := range rs {
182		ns = append(ns, n)
183	}
184	sort.Slice(ns, func(i, j int) bool { return ns[i] < ns[j] })
185
186	for _, n := range ns {
187		var leftBracket, rightBracket string
188		if len(rs[n]) > 1 {
189			leftBracket, rightBracket = "[", "]"
190		}
191
192		b = strconv.AppendInt(b, int64(n), 10)
193		b = append(b, ':')
194		b = append(b, leftBracket...)
195		for _, r := range rs[n] {
196			num, typ, n := protowire.ConsumeTag(r)
197			r = r[n:]
198			switch typ {
199			case protowire.VarintType:
200				v, _ := protowire.ConsumeVarint(r)
201				b = strconv.AppendInt(b, int64(v), 10)
202			case protowire.Fixed32Type:
203				v, _ := protowire.ConsumeFixed32(r)
204				b = append(b, fmt.Sprintf("0x%08x", v)...)
205			case protowire.Fixed64Type:
206				v, _ := protowire.ConsumeFixed64(r)
207				b = append(b, fmt.Sprintf("0x%016x", v)...)
208			case protowire.BytesType:
209				v, _ := protowire.ConsumeBytes(r)
210				b = strconv.AppendQuote(b, string(v))
211			case protowire.StartGroupType:
212				v, _ := protowire.ConsumeGroup(num, r)
213				b = append(b, '{')
214				b = appendUnknown(b, v)
215				b = bytes.TrimRight(b, delim())
216				b = append(b, '}')
217			default:
218				panic(fmt.Sprintf("invalid type: %v", typ))
219			}
220			b = append(b, delim()...)
221		}
222		b = bytes.TrimRight(b, delim())
223		b = append(b, rightBracket...)
224		b = append(b, delim()...)
225	}
226	return b
227}
228
229func appendList(b []byte, v protoreflect.List, fd protoreflect.FieldDescriptor) []byte {
230	b = append(b, '[')
231	for i := 0; i < v.Len(); i++ {
232		b = appendValue(b, v.Get(i), fd)
233		b = append(b, delim()...)
234	}
235	b = bytes.TrimRight(b, delim())
236	b = append(b, ']')
237	return b
238}
239
240func appendMap(b []byte, v protoreflect.Map, fd protoreflect.FieldDescriptor) []byte {
241	b = append(b, '{')
242	order.RangeEntries(v, order.GenericKeyOrder, func(k protoreflect.MapKey, v protoreflect.Value) bool {
243		b = appendValue(b, k.Value(), fd.MapKey())
244		b = append(b, ':')
245		b = appendValue(b, v, fd.MapValue())
246		b = append(b, delim()...)
247		return true
248	})
249	b = bytes.TrimRight(b, delim())
250	b = append(b, '}')
251	return b
252}
253
254func delim() string {
255	// Deliberately introduce instability into the message string to
256	// discourage users from depending on it.
257	if detrand.Bool() {
258		return "  "
259	}
260	return ", "
261}
262