diff options
Diffstat (limited to 'vendor/github.com/aws/smithy-go/logging/logger.go')
| -rw-r--r-- | vendor/github.com/aws/smithy-go/logging/logger.go | 82 |
1 files changed, 82 insertions, 0 deletions
diff --git a/vendor/github.com/aws/smithy-go/logging/logger.go b/vendor/github.com/aws/smithy-go/logging/logger.go new file mode 100644 index 0000000..2071924 --- /dev/null +++ b/vendor/github.com/aws/smithy-go/logging/logger.go @@ -0,0 +1,82 @@ +package logging + +import ( + "context" + "io" + "log" +) + +// Classification is the type of the log entry's classification name. +type Classification string + +// Set of standard classifications that can be used by clients and middleware +const ( + Warn Classification = "WARN" + Debug Classification = "DEBUG" +) + +// Logger is an interface for logging entries at certain classifications. +type Logger interface { + // Logf is expected to support the standard fmt package "verbs". + Logf(classification Classification, format string, v ...interface{}) +} + +// LoggerFunc is a wrapper around a function to satisfy the Logger interface. +type LoggerFunc func(classification Classification, format string, v ...interface{}) + +// Logf delegates the logging request to the wrapped function. +func (f LoggerFunc) Logf(classification Classification, format string, v ...interface{}) { + f(classification, format, v...) +} + +// ContextLogger is an optional interface a Logger implementation may expose that provides +// the ability to create context aware log entries. +type ContextLogger interface { + WithContext(context.Context) Logger +} + +// WithContext will pass the provided context to logger if it implements the ContextLogger interface and return the resulting +// logger. Otherwise the logger will be returned as is. As a special case if a nil logger is provided, a Nop logger will +// be returned to the caller. +func WithContext(ctx context.Context, logger Logger) Logger { + if logger == nil { + return Nop{} + } + + cl, ok := logger.(ContextLogger) + if !ok { + return logger + } + + return cl.WithContext(ctx) +} + +// Nop is a Logger implementation that simply does not perform any logging. +type Nop struct{} + +// Logf simply returns without performing any action +func (n Nop) Logf(Classification, string, ...interface{}) { + return +} + +// StandardLogger is a Logger implementation that wraps the standard library logger, and delegates logging to it's +// Printf method. +type StandardLogger struct { + Logger *log.Logger +} + +// Logf logs the given classification and message to the underlying logger. +func (s StandardLogger) Logf(classification Classification, format string, v ...interface{}) { + if len(classification) != 0 { + format = string(classification) + " " + format + } + + s.Logger.Printf(format, v...) +} + +// NewStandardLogger returns a new StandardLogger +func NewStandardLogger(writer io.Writer) *StandardLogger { + return &StandardLogger{ + Logger: log.New(writer, "SDK ", log.LstdFlags), + } +} |
