package middleware
import (
"bytes"
"io"
"os"
"strconv"
"strings"
"sync"
"time"
"github.com/labstack/echo"
"github.com/labstack/gommon/color"
"github.com/valyala/fasttemplate"
)
type (
// LoggerConfig defines the config for Logger middleware.
LoggerConfig struct {
// Skipper defines a function to skip middleware.
Skipper Skipper
// Tags to constructed the logger format.
//
// - time_unix
// - time_unix_nano
// - time_rfc3339
// - time_rfc3339_nano
// - time_custom
// - id (Request ID)
// - remote_ip
// - uri
// - host
// - method
// - path
// - referer
// - user_agent
// - status
// - latency (In nanoseconds)
// - latency_human (Human readable)
// - bytes_in (Bytes received)
// - bytes_out (Bytes sent)
// - header:<NAME>
// - query:<NAME>
// - form:<NAME>
//
// Example "${remote_ip} ${status}"
//
// Optional. Default value DefaultLoggerConfig.Format.
Format string `yaml:"format"`
// Optional. Default value DefaultLoggerConfig.CustomTimeFormat.
CustomTimeFormat string `yaml:"custom_time_format"`
// Output is a writer where logs in JSON format are written.
// Optional. Default value os.Stdout.
Output io.Writer
template *fasttemplate.Template
colorer *color.Color
pool *sync.Pool
}
)
var (
// DefaultLoggerConfig is the default Logger middleware config.
DefaultLoggerConfig = LoggerConfig{
Skipper: DefaultSkipper,
Format: `{"time":"${time_rfc3339_nano}","id":"${id}","remote_ip":"${remote_ip}","host":"${host}",` +
`"method":"${method}","uri":"${uri}","status":${status}, "latency":${latency},` +
`"latency_human":"${latency_human}","bytes_in":${bytes_in},` +
`"bytes_out":${bytes_out}}` + "\n",
CustomTimeFormat: "2006-01-02 15:04:05.00000",
Output: os.Stdout,
colorer: color.New(),
}
)
// Logger returns a middleware that logs HTTP requests.
func Logger() echo.MiddlewareFunc {
return LoggerWithConfig(DefaultLoggerConfig)
}
// LoggerWithConfig returns a Logger middleware with config.
// See: `Logger()`.
func LoggerWithConfig(config LoggerConfig) echo.MiddlewareFunc {
// Defaults
if config.Skipper == nil {
config.Skipper = DefaultLoggerConfig.Skipper
}
if config.Format == "" {
config.Format = DefaultLoggerConfig.Format
}
if config.Output == nil {
config.Output = DefaultLoggerConfig.Output
}
config.template = fasttemplate.New(config.Format, "${", "}")
config.colorer = color.New()
config.colorer.SetOutput(config.Output)
config.pool = &sync.Pool{
New: func() interface{} {
return bytes.NewBuffer(make([]byte, 256))
},
}
return func(next echo.HandlerFunc) echo.HandlerFunc {
return func(c echo.Context) (err error) {
if config.Skipper(c) {
return next(c)
}
req := c.Request()
res := c.Response()
start := time.Now()
if err = next(c); err != nil {
c.Error(err)
}
stop := time.Now()
buf := config.pool.Get().(*bytes.Buffer)
buf.Reset()
defer config.pool.Put(buf)
if _, err = config.template.ExecuteFunc(buf, func(w io.Writer, tag string) (int, error) {
switch tag {
case "time_unix":
return buf.WriteString(strconv.FormatInt(time.Now().Unix(), 10))
case "time_unix_nano":
return buf.WriteString(strconv.FormatInt(time.Now().UnixNano(), 10))
case "time_rfc3339":
return buf.WriteString(time.Now().Format(time.RFC3339))
case "time_rfc3339_nano":
return buf.WriteString(time.Now().Format(time.RFC3339Nano))
case "time_custom":
return buf.WriteString(time.Now().Format(config.CustomTimeFormat))
case "id":
id := req.Header.Get(echo.HeaderXRequestID)
if id == "" {
id = res.Header().Get(echo.HeaderXRequestID)
}
return buf.WriteString(id)
case "remote_ip":
return buf.WriteString(c.RealIP())
case "host":
return buf.WriteString(req.Host)
case "uri":
return buf.WriteString(req.RequestURI)
case "method":
return buf.WriteString(req.Method)
case "path":
p := req.URL.Path
if p == "" {
p = "/"
}
return buf.WriteString(p)
case "referer":
return buf.WriteString(req.Referer())
case "user_agent":
return buf.WriteString(req.UserAgent())
case "status":
n := res.Status
s := config.colorer.Green(n)
switch {
case n >= 500:
s = config.colorer.Red(n)
case n >= 400:
s = config.colorer.Yellow(n)
case n >= 300:
s = config.colorer.Cyan(n)
}
return buf.WriteString(s)
case "latency":
l := stop.Sub(start)
return buf.WriteString(strconv.FormatInt(int64(l), 10))
case "latency_human":
return buf.WriteString(stop.Sub(start).String())
case "bytes_in":
cl := req.Header.Get(echo.HeaderContentLength)
if cl == "" {
cl = "0"
}
return buf.WriteString(cl)
case "bytes_out":
return buf.WriteString(strconv.FormatInt(res.Size, 10))
default:
switch {
case strings.HasPrefix(tag, "header:"):
return buf.Write([]byte(c.Request().Header.Get(tag[7:])))
case strings.HasPrefix(tag, "query:"):
return buf.Write([]byte(c.QueryParam(tag[6:])))
case strings.HasPrefix(tag, "form:"):
return buf.Write([]byte(c.FormValue(tag[5:])))
case strings.HasPrefix(tag, "cookie:"):
cookie, err := c.Cookie(tag[7:])
if err == nil {
return buf.Write([]byte(cookie.Value))
}
}
}
return 0, nil
}); err != nil {
return
}
_, err = config.Output.Write(buf.Bytes())
return
}
}
}