1 /* 2 Copyright 2021 The Kubernetes Authors. 3 4 Licensed under the Apache License, Version 2.0 (the "License"); 5 you may not use this file except in compliance with the License. 6 You may obtain a copy of the License at 7 8 http://www.apache.org/licenses/LICENSE-2.0 9 10 Unless required by applicable law or agreed to in writing, software 11 distributed under the License is distributed on an "AS IS" BASIS, 12 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 See the License for the specific language governing permissions and 14 limitations under the License. 15 */ 16 17 package ktesting 18 19 import ( 20 "flag" 21 "strconv" 22 23 "k8s.io/klog/v2/internal/serialize" 24 "k8s.io/klog/v2/internal/verbosity" 25 ) 26 27 // Config influences logging in a test logger. To make this configurable via 28 // command line flags, instantiate this once per program and use AddFlags to 29 // bind command line flags to the instance before passing it to NewTestContext. 30 // 31 // Must be constructed with NewConfig. 32 type Config struct { 33 vstate *verbosity.VState 34 co configOptions 35 } 36 37 // Verbosity returns a value instance that can be used to query (via String) or 38 // modify (via Set) the verbosity threshold. This is thread-safe and can be 39 // done at runtime. 40 func (c *Config) Verbosity() flag.Value { 41 return c.vstate.V() 42 } 43 44 // VModule returns a value instance that can be used to query (via String) or 45 // modify (via Set) the vmodule settings. This is thread-safe and can be done 46 // at runtime. 47 func (c *Config) VModule() flag.Value { 48 return c.vstate.VModule() 49 } 50 51 // ConfigOption implements functional parameters for NewConfig. 52 type ConfigOption func(co *configOptions) 53 54 type configOptions struct { 55 anyToString serialize.AnyToStringFunc 56 verbosityFlagName string 57 vmoduleFlagName string 58 verbosityDefault int 59 bufferLogs bool 60 } 61 62 // AnyToString overrides the default formatter for values that are not 63 // supported directly by klog. The default is `fmt.Sprintf("%+v")`. 64 // The formatter must not panic. 65 func AnyToString(anyToString func(value interface{}) string) ConfigOption { 66 return func(co *configOptions) { 67 co.anyToString = anyToString 68 } 69 } 70 71 // VerbosityFlagName overrides the default -testing.v for the verbosity level. 72 func VerbosityFlagName(name string) ConfigOption { 73 return func(co *configOptions) { 74 co.verbosityFlagName = name 75 } 76 } 77 78 // VModulFlagName overrides the default -testing.vmodule for the per-module 79 // verbosity levels. 80 func VModuleFlagName(name string) ConfigOption { 81 return func(co *configOptions) { 82 co.vmoduleFlagName = name 83 } 84 } 85 86 // Verbosity overrides the default verbosity level of 5. That default is higher 87 // than in klog itself because it enables logging entries for "the steps 88 // leading up to errors and warnings" and "troubleshooting" (see 89 // https://github.com/kubernetes/community/blob/9406b4352fe2d5810cb21cc3cb059ce5886de157/contributors/devel/sig-instrumentation/logging.md#logging-conventions), 90 // which is useful when debugging a failed test. `go test` only shows the log 91 // output for failed tests. To see all output, use `go test -v`. 92 func Verbosity(level int) ConfigOption { 93 return func(co *configOptions) { 94 co.verbosityDefault = level 95 } 96 } 97 98 // BufferLogs controls whether log entries are captured in memory in addition 99 // to being printed. Off by default. Unit tests that want to verify that 100 // log entries are emitted as expected can turn this on and then retrieve 101 // the captured log through the Underlier LogSink interface. 102 func BufferLogs(enabled bool) ConfigOption { 103 return func(co *configOptions) { 104 co.bufferLogs = enabled 105 } 106 } 107 108 // NewConfig returns a configuration with recommended defaults and optional 109 // modifications. Command line flags are not bound to any FlagSet yet. 110 func NewConfig(opts ...ConfigOption) *Config { 111 c := &Config{ 112 co: configOptions{ 113 verbosityFlagName: "testing.v", 114 vmoduleFlagName: "testing.vmodule", 115 verbosityDefault: 5, 116 }, 117 } 118 for _, opt := range opts { 119 opt(&c.co) 120 } 121 122 c.vstate = verbosity.New() 123 // Cannot fail for this input. 124 _ = c.vstate.V().Set(strconv.FormatInt(int64(c.co.verbosityDefault), 10)) 125 return c 126 } 127 128 // AddFlags registers the command line flags that control the configuration. 129 func (c *Config) AddFlags(fs *flag.FlagSet) { 130 fs.Var(c.vstate.V(), c.co.verbosityFlagName, "number for the log level verbosity of the testing logger") 131 fs.Var(c.vstate.VModule(), c.co.vmoduleFlagName, "comma-separated list of pattern=N log level settings for files matching the patterns") 132 } 133