1/*
2 *
3 * Copyright 2017 gRPC authors.
4 *
5 * Licensed under the Apache License, Version 2.0 (the "License");
6 * you may not use this file except in compliance with the License.
7 * You may obtain a copy of the License at
8 *
9 *     http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the License for the specific language governing permissions and
15 * limitations under the License.
16 *
17 */
18
19package grpclog
20
21import (
22	"io"
23	"io/ioutil"
24	"log"
25	"os"
26	"strconv"
27)
28
29// LoggerV2 does underlying logging work for grpclog.
30type LoggerV2 interface {
31	// Info logs to INFO log. Arguments are handled in the manner of fmt.Print.
32	Info(args ...interface{})
33	// Infoln logs to INFO log. Arguments are handled in the manner of fmt.Println.
34	Infoln(args ...interface{})
35	// Infof logs to INFO log. Arguments are handled in the manner of fmt.Printf.
36	Infof(format string, args ...interface{})
37	// Warning logs to WARNING log. Arguments are handled in the manner of fmt.Print.
38	Warning(args ...interface{})
39	// Warningln logs to WARNING log. Arguments are handled in the manner of fmt.Println.
40	Warningln(args ...interface{})
41	// Warningf logs to WARNING log. Arguments are handled in the manner of fmt.Printf.
42	Warningf(format string, args ...interface{})
43	// Error logs to ERROR log. Arguments are handled in the manner of fmt.Print.
44	Error(args ...interface{})
45	// Errorln logs to ERROR log. Arguments are handled in the manner of fmt.Println.
46	Errorln(args ...interface{})
47	// Errorf logs to ERROR log. Arguments are handled in the manner of fmt.Printf.
48	Errorf(format string, args ...interface{})
49	// Fatal logs to ERROR log. Arguments are handled in the manner of fmt.Print.
50	// gRPC ensures that all Fatal logs will exit with os.Exit(1).
51	// Implementations may also call os.Exit() with a non-zero exit code.
52	Fatal(args ...interface{})
53	// Fatalln logs to ERROR log. Arguments are handled in the manner of fmt.Println.
54	// gRPC ensures that all Fatal logs will exit with os.Exit(1).
55	// Implementations may also call os.Exit() with a non-zero exit code.
56	Fatalln(args ...interface{})
57	// Fatalf logs to ERROR log. Arguments are handled in the manner of fmt.Printf.
58	// gRPC ensures that all Fatal logs will exit with os.Exit(1).
59	// Implementations may also call os.Exit() with a non-zero exit code.
60	Fatalf(format string, args ...interface{})
61	// V reports whether verbosity level l is at least the requested verbose level.
62	V(l int) bool
63}
64
65// SetLoggerV2 sets logger that is used in grpc to a V2 logger.
66// Not mutex-protected, should be called before any gRPC functions.
67func SetLoggerV2(l LoggerV2) {
68	logger = l
69}
70
71const (
72	// infoLog indicates Info severity.
73	infoLog int = iota
74	// warningLog indicates Warning severity.
75	warningLog
76	// errorLog indicates Error severity.
77	errorLog
78	// fatalLog indicates Fatal severity.
79	fatalLog
80)
81
82// severityName contains the string representation of each severity.
83var severityName = []string{
84	infoLog:    "INFO",
85	warningLog: "WARNING",
86	errorLog:   "ERROR",
87	fatalLog:   "FATAL",
88}
89
90// loggerT is the default logger used by grpclog.
91type loggerT struct {
92	m []*log.Logger
93	v int
94}
95
96// NewLoggerV2 creates a loggerV2 with the provided writers.
97// Fatal logs will be written to errorW, warningW, infoW, followed by exit(1).
98// Error logs will be written to errorW, warningW and infoW.
99// Warning logs will be written to warningW and infoW.
100// Info logs will be written to infoW.
101func NewLoggerV2(infoW, warningW, errorW io.Writer) LoggerV2 {
102	return NewLoggerV2WithVerbosity(infoW, warningW, errorW, 0)
103}
104
105// NewLoggerV2WithVerbosity creates a loggerV2 with the provided writers and
106// verbosity level.
107func NewLoggerV2WithVerbosity(infoW, warningW, errorW io.Writer, v int) LoggerV2 {
108	var m []*log.Logger
109	m = append(m, log.New(infoW, severityName[infoLog]+": ", log.LstdFlags))
110	m = append(m, log.New(io.MultiWriter(infoW, warningW), severityName[warningLog]+": ", log.LstdFlags))
111	ew := io.MultiWriter(infoW, warningW, errorW) // ew will be used for error and fatal.
112	m = append(m, log.New(ew, severityName[errorLog]+": ", log.LstdFlags))
113	m = append(m, log.New(ew, severityName[fatalLog]+": ", log.LstdFlags))
114	return &loggerT{m: m, v: v}
115}
116
117// newLoggerV2 creates a loggerV2 to be used as default logger.
118// All logs are written to stderr.
119func newLoggerV2() LoggerV2 {
120	errorW := ioutil.Discard
121	warningW := ioutil.Discard
122	infoW := ioutil.Discard
123
124	logLevel := os.Getenv("GRPC_GO_LOG_SEVERITY_LEVEL")
125	switch logLevel {
126	case "", "ERROR", "error": // If env is unset, set level to ERROR.
127		errorW = os.Stderr
128	case "WARNING", "warning":
129		warningW = os.Stderr
130	case "INFO", "info":
131		infoW = os.Stderr
132	}
133
134	var v int
135	vLevel := os.Getenv("GRPC_GO_LOG_VERBOSITY_LEVEL")
136	if vl, err := strconv.Atoi(vLevel); err == nil {
137		v = vl
138	}
139	return NewLoggerV2WithVerbosity(infoW, warningW, errorW, v)
140}
141
142func (g *loggerT) Info(args ...interface{}) {
143	g.m[infoLog].Print(args...)
144}
145
146func (g *loggerT) Infoln(args ...interface{}) {
147	g.m[infoLog].Println(args...)
148}
149
150func (g *loggerT) Infof(format string, args ...interface{}) {
151	g.m[infoLog].Printf(format, args...)
152}
153
154func (g *loggerT) Warning(args ...interface{}) {
155	g.m[warningLog].Print(args...)
156}
157
158func (g *loggerT) Warningln(args ...interface{}) {
159	g.m[warningLog].Println(args...)
160}
161
162func (g *loggerT) Warningf(format string, args ...interface{}) {
163	g.m[warningLog].Printf(format, args...)
164}
165
166func (g *loggerT) Error(args ...interface{}) {
167	g.m[errorLog].Print(args...)
168}
169
170func (g *loggerT) Errorln(args ...interface{}) {
171	g.m[errorLog].Println(args...)
172}
173
174func (g *loggerT) Errorf(format string, args ...interface{}) {
175	g.m[errorLog].Printf(format, args...)
176}
177
178func (g *loggerT) Fatal(args ...interface{}) {
179	g.m[fatalLog].Fatal(args...)
180	// No need to call os.Exit() again because log.Logger.Fatal() calls os.Exit().
181}
182
183func (g *loggerT) Fatalln(args ...interface{}) {
184	g.m[fatalLog].Fatalln(args...)
185	// No need to call os.Exit() again because log.Logger.Fatal() calls os.Exit().
186}
187
188func (g *loggerT) Fatalf(format string, args ...interface{}) {
189	g.m[fatalLog].Fatalf(format, args...)
190	// No need to call os.Exit() again because log.Logger.Fatal() calls os.Exit().
191}
192
193func (g *loggerT) V(l int) bool {
194	return l <= g.v
195}
196