logger

README

Logger

This is a highly opinionated wrapper around the zap logger.

Usage

Create a new logger near the entrypoint of your code.

logger, err := logger.New(ctx, false) // Without debug

Make sure to call the Clean function when you're done with the usage.

defer logger.Clean()

You can now add this logger to a context.

ctx = NewContextWithLogger(ctx, logger)

If you pass this context correctly to the call site, you can fetch the logger from the context and use its functions.

logger = NewLoggerFromContext(ctx)
logger.Info("This is an info message")

One of the primary reasons for creating this package is to easily append fields to a logger for additional debugging.

You can set global fields to the logger.

logger = logger.WithField("name", name) // All subsequent calls to this logger will log the name field.

You can also set local fields only to the log message.

logger.WithField("name", name).Info("Login user")

The logger also supports multiple fields.

	logger.WithFields(Fields(
		"test-key", "test-value",
		"test-other-key", 1,
	)).Info("This is an info message with multiple field")

Documentation

Overview

Package logger is a highly opinionated wrapper around the Zap logger

Index

• func Fields(a ...any) (fields []zapcore.Field)
• func NewContextWithLogger(parentCtx context.Context, logger *Logger) context.Context
• type Field
• type Logger
  • func LoggerFromContext(ctx context.Context) *Logger
  • func New(ctx context.Context, debug bool) (*Logger, error)
  • func (l *Logger) Clean()
  • func (l *Logger) Debug(msg string)
  • func (l *Logger) Error(msg string)
  • func (l *Logger) Fatal(msg string)
  • func (l *Logger) Info(msg string)
  • func (logger *Logger) Middleware() func(http.Handler) http.Handler
  • func (l *Logger) Warn(msg string)
  • func (l *Logger) WithError(err error) *Logger
  • func (l *Logger) WithField(key string, val interface{}) *Logger
  • func (l *Logger) WithFields(f []zapcore.Field) *Logger
• type Options

Functions

func Fields

func Fields(a ...any) (fields []zapcore.Field)

Fields accepts the values as a string:interface pair. If the pairs don't match, they will be skipped

func NewContextWithLogger

func NewContextWithLogger(parentCtx context.Context, logger *Logger) context.Context

NewContextWithLogger returns a new context with a logger and panics if it doesn't match the interface.

Types

type Field

type Field struct {
	Key   string
	Value interface{}
}

Field represents a logger field.

type Logger

type Logger struct {
	// contains filtered or unexported fields
}

Logger wraps zap.Logger.

func LoggerFromContext

func LoggerFromContext(ctx context.Context) *Logger

LoggerFromContext retrieves a logger from a context and panics if there isn't one.

func New

func New(ctx context.Context, debug bool) (*Logger, error)

New creates a new logger. Make sure to call defer logger.Clean() after calling this. Log messages are JSON Encoded and timestamps are RFC3339 encoded.

func (*Logger) Clean

func (l *Logger) Clean()

Clean cleans up the log states. Make sure to call this after creating a new logger.

func (*Logger) Debug

func (l *Logger) Debug(msg string)

Debug logs a Debug level message.

func (*Logger) Error

func (l *Logger) Error(msg string)

Error logs a Error level message.

func (*Logger) Fatal

func (l *Logger) Fatal(msg string)

Fatal logs a Fatal message.

func (*Logger) Info

func (l *Logger) Info(msg string)

Info logs a Info level message.

func (*Logger) Middleware

func (logger *Logger) Middleware() func(http.Handler) http.Handler

Middleware is a middleware that adds the logger to the request context.

func (*Logger) Warn

func (l *Logger) Warn(msg string)

Warn logs a Warning level message.

func (*Logger) WithError

func (l *Logger) WithError(err error) *Logger

WithError returns a new logger with the provided error.

func (*Logger) WithField

func (l *Logger) WithField(key string, val interface{}) *Logger

WithField returns a new logger with the provided field.

func (*Logger) WithFields

func (l *Logger) WithFields(f []zapcore.Field) *Logger

WithFields returns a logger with the providedfields.

type Options

type Options struct {
}

Options is the logger options.