logger

README

logger

Gin middleware/handler to logger url path using rs/zerolog.

Example

package main

import (
  "fmt"
  "net/http"
  "regexp"
  "time"

  "github.com/gin-contrib/logger"
  "github.com/gin-contrib/requestid"
  "github.com/gin-gonic/gin"
  "github.com/rs/zerolog"
  "github.com/rs/zerolog/log"
)

var rxURL = regexp.MustCompile(`^/regexp\d*`)

func main() {
  r := gin.New()

  // Add a logger middleware, which:
  //   - Logs all requests, like a combined access and error log.
  //   - Logs to stdout.
  // r.Use(logger.SetLogger())

  // Example pong request.
  r.GET("/pong", logger.SetLogger(), func(c *gin.Context) {
    c.String(http.StatusOK, "pong "+fmt.Sprint(time.Now().Unix()))
  })

  // Example ping request.
  r.GET("/ping", logger.SetLogger(
    logger.WithSkipPath([]string{"/skip"}),
    logger.WithUTC(true),
    logger.WithSkipPathRegexps(rxURL),
  ), func(c *gin.Context) {
    c.String(http.StatusOK, "pong "+fmt.Sprint(time.Now().Unix()))
  })

  // Example skip path request.
  r.GET("/skip", logger.SetLogger(
    logger.WithSkipPath([]string{"/skip"}),
  ), func(c *gin.Context) {
    c.String(http.StatusOK, "pong "+fmt.Sprint(time.Now().Unix()))
  })

  // Example skip path request.
  r.GET("/regexp1", logger.SetLogger(
    logger.WithSkipPathRegexps(rxURL),
  ), func(c *gin.Context) {
    c.String(http.StatusOK, "pong "+fmt.Sprint(time.Now().Unix()))
  })

  // Example skip path request.
  r.GET("/regexp2", logger.SetLogger(
    logger.WithSkipPathRegexps(rxURL),
  ), func(c *gin.Context) {
    c.String(http.StatusOK, "pong "+fmt.Sprint(time.Now().Unix()))
  })

  // add custom fields.
  r.GET("/id", requestid.New(requestid.WithGenerator(func() string {
    return "foobar"
  })), logger.SetLogger(
    logger.WithLogger(func(c *gin.Context, l zerolog.Logger) zerolog.Logger {
      if trace.SpanFromContext(c.Request.Context()).SpanContext().IsValid() {
        l = l.With().
          Str("trace_id", trace.SpanFromContext(c.Request.Context()).SpanContext().TraceID().String()).
          Str("span_id", trace.SpanFromContext(c.Request.Context()).SpanContext().SpanID().String()).
          Logger()
      }

      return l.With().
        Str("id", requestid.Get(c)).
        Str("foo", "bar").
        Str("path", c.Request.URL.Path).
        Logger()
    }),
  ), func(c *gin.Context) {
    c.String(http.StatusOK, "pong "+fmt.Sprint(time.Now().Unix()))
  })

  // Example of JSON format log
  r.GET("/json", logger.SetLogger(
    logger.WithLogger(func(_ *gin.Context, l zerolog.Logger) zerolog.Logger {
      return l.Output(gin.DefaultWriter).With().Logger()
    }),
  ), func(c *gin.Context) {
    c.String(http.StatusOK, "pong "+fmt.Sprint(time.Now().Unix()))
  })

  // Example of skipper usage
  r.GET("/health", logger.SetLogger(
    logger.WithSkipper(func(c *gin.Context) bool {
      return c.Request.URL.Path == "/health"
    }),
  ), func(c *gin.Context) {
    c.String(http.StatusOK, "pong "+fmt.Sprint(time.Now().Unix()))
  })

  // Listen and Server in 0.0.0.0:8080
  if err := r.Run(":8080"); err != nil {
    log.Fatal().Msg("can' start server with 8080 port")
  }
}

Screenshot

Run app server:

go run _example/main.go

Test request:

curl http://localhost:8080/ping
curl http://localhost:8080/pong
curl http://localhost:8080/json

Documentation

Index

• func ParseLevel(levelStr string) (zerolog.Level, error)
• func SetLogger(opts ...Option) gin.HandlerFunc
• type Fn
• type Option
  • func WithClientErrorLevel(lvl zerolog.Level) Option
  • func WithDefaultLevel(lvl zerolog.Level) Option
  • func WithLogger(fn func(*gin.Context, zerolog.Logger) zerolog.Logger) Option
  • func WithPathLevel(m map[string]zerolog.Level) Option
  • func WithServerErrorLevel(lvl zerolog.Level) Option
  • func WithSkipPath(s []string) Option
  • func WithSkipPathRegexps(regs ...*regexp.Regexp) Option
  • func WithSkipper(s Skipper) Option
  • func WithUTC(s bool) Option
  • func WithWriter(s io.Writer) Option
• type Skipper

Functions

func ParseLevel

func ParseLevel(levelStr string) (zerolog.Level, error)

ParseLevel converts a level string into a zerolog Level value. returns an error if the input string does not match known values.

func SetLogger

func SetLogger(opts ...Option) gin.HandlerFunc

SetLogger initializes the logging middleware.

Types

type Fn

type Fn func(*gin.Context, zerolog.Logger) zerolog.Logger

type Option

type Option interface {
	// contains filtered or unexported methods
}

Option specifies instrumentation configuration options.

func WithClientErrorLevel

func WithClientErrorLevel(lvl zerolog.Level) Option

WithClientErrorLevel set the log level used for request with status code between 400 and 499

func WithDefaultLevel

func WithDefaultLevel(lvl zerolog.Level) Option

WithDefaultLevel set the log level used for request with status code < 400

func WithLogger

func WithLogger(fn func(*gin.Context, zerolog.Logger) zerolog.Logger) Option

WithLogger set custom logger func

func WithPathLevel

func WithPathLevel(m map[string]zerolog.Level) Option

WithPathLevel use logging level for successful requests to a specific path

func WithServerErrorLevel

func WithServerErrorLevel(lvl zerolog.Level) Option

WithServerErrorLevel set the log level used for request with status code >= 500

func WithSkipPath

func WithSkipPath(s []string) Option

WithSkipPath skip URL path by specific pattern

func WithSkipPathRegexps

func WithSkipPathRegexps(regs ...*regexp.Regexp) Option

WithSkipPathRegexps multiple skip URL paths by regexp pattern

func WithSkipper

func WithSkipper(s Skipper) Option

WithSkipper set function to skip middleware requests with this function returning true will not have their logs written Default is nil

func WithUTC

func WithUTC(s bool) Option

WithUTC returns t with the location set to UTC.

func WithWriter

func WithWriter(s io.Writer) Option

WithWriter change the default output writer. Default is gin.DefaultWriter

type Skipper

type Skipper func(c *gin.Context) bool

Skipper is a function to skip logs based on provided Context