vendor/google.golang.org/grpc/internal/binarylog/binarylog.go

   1 /*
   2  *
   3  * Copyright 2018 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
  19 // Package binarylog implementation binary logging as defined in
  20 // https://github.com/grpc/proposal/blob/master/A16-binary-logging.md.
  21 package binarylog
  22
  23 import (
  24         "fmt"
  25         "os"
  26
  27         "google.golang.org/grpc/grpclog"
  28 )
  29
  30 // Logger is the global binary logger. It can be used to get binary logger for
  31 // each method.
  32 type Logger interface {
  33         getMethodLogger(methodName string) *MethodLogger
  34 }
  35
  36 // binLogger is the global binary logger for the binary. One of this should be
  37 // built at init time from the configuration (environment varialbe or flags).
  38 //
  39 // It is used to get a methodLogger for each individual method.
  40 var binLogger Logger
  41
  42 // SetLogger sets the binarg logger.
  43 //
  44 // Only call this at init time.
  45 func SetLogger(l Logger) {
  46         binLogger = l
  47 }
  48
  49 // GetMethodLogger returns the methodLogger for the given methodName.
  50 //
  51 // methodName should be in the format of "/service/method".
  52 //
  53 // Each methodLogger returned by this method is a new instance. This is to
  54 // generate sequence id within the call.
  55 func GetMethodLogger(methodName string) *MethodLogger {
  56         if binLogger == nil {
  57                 return nil
  58         }
  59         return binLogger.getMethodLogger(methodName)
  60 }
  61
  62 func init() {
  63         const envStr = "GRPC_BINARY_LOG_FILTER"
  64         configStr := os.Getenv(envStr)
  65         binLogger = NewLoggerFromConfigString(configStr)
  66 }
  67
  68 type methodLoggerConfig struct {
  69         // Max length of header and message.
  70         hdr, msg uint64
  71 }
  72
  73 type logger struct {
  74         all      *methodLoggerConfig
  75         services map[string]*methodLoggerConfig
  76         methods  map[string]*methodLoggerConfig
  77
  78         blacklist map[string]struct{}
  79 }
  80
  81 // newEmptyLogger creates an empty logger. The map fields need to be filled in
  82 // using the set* functions.
  83 func newEmptyLogger() *logger {
  84         return &logger{}
  85 }
  86
  87 // Set method logger for "*".
  88 func (l *logger) setDefaultMethodLogger(ml *methodLoggerConfig) error {
  89         if l.all != nil {
  90                 return fmt.Errorf("conflicting global rules found")
  91         }
  92         l.all = ml
  93         return nil
  94 }
  95
  96 // Set method logger for "service/*".
  97 //
  98 // New methodLogger with same service overrides the old one.
  99 func (l *logger) setServiceMethodLogger(service string, ml *methodLoggerConfig) error {
 100         if _, ok := l.services[service]; ok {
 101                 return fmt.Errorf("conflicting rules for service %v found", service)
 102         }
 103         if l.services == nil {
 104                 l.services = make(map[string]*methodLoggerConfig)
 105         }
 106         l.services[service] = ml
 107         return nil
 108 }
 109
 110 // Set method logger for "service/method".
 111 //
 112 // New methodLogger with same method overrides the old one.
 113 func (l *logger) setMethodMethodLogger(method string, ml *methodLoggerConfig) error {
 114         if _, ok := l.blacklist[method]; ok {
 115                 return fmt.Errorf("conflicting rules for method %v found", method)
 116         }
 117         if _, ok := l.methods[method]; ok {
 118                 return fmt.Errorf("conflicting rules for method %v found", method)
 119         }
 120         if l.methods == nil {
 121                 l.methods = make(map[string]*methodLoggerConfig)
 122         }
 123         l.methods[method] = ml
 124         return nil
 125 }
 126
 127 // Set blacklist method for "-service/method".
 128 func (l *logger) setBlacklist(method string) error {
 129         if _, ok := l.blacklist[method]; ok {
 130                 return fmt.Errorf("conflicting rules for method %v found", method)
 131         }
 132         if _, ok := l.methods[method]; ok {
 133                 return fmt.Errorf("conflicting rules for method %v found", method)
 134         }
 135         if l.blacklist == nil {
 136                 l.blacklist = make(map[string]struct{})
 137         }
 138         l.blacklist[method] = struct{}{}
 139         return nil
 140 }
 141
 142 // getMethodLogger returns the methodLogger for the given methodName.
 143 //
 144 // methodName should be in the format of "/service/method".
 145 //
 146 // Each methodLogger returned by this method is a new instance. This is to
 147 // generate sequence id within the call.
 148 func (l *logger) getMethodLogger(methodName string) *MethodLogger {
 149         s, m, err := parseMethodName(methodName)
 150         if err != nil {
 151                 grpclog.Infof("binarylogging: failed to parse %q: %v", methodName, err)
 152                 return nil
 153         }
 154         if ml, ok := l.methods[s+"/"+m]; ok {
 155                 return newMethodLogger(ml.hdr, ml.msg)
 156         }
 157         if _, ok := l.blacklist[s+"/"+m]; ok {
 158                 return nil
 159         }
 160         if ml, ok := l.services[s]; ok {
 161                 return newMethodLogger(ml.hdr, ml.msg)
 162         }
 163         if l.all == nil {
 164                 return nil
 165         }
 166         return newMethodLogger(l.all.hdr, l.all.msg)
 167 }