logger.go at master ⋅ gin-gonic/gin

// Copyright 2014 Manu Martinez-Almeida.  All rights reserved.
// Use of this source code is governed by a MIT style
// license that can be found in the LICENSE file.

package gin

import (
	"fmt"
	"io"
	"net/http"
	"os"
	"time"

	"github.com/mattn/go-isatty"
)

type consoleColorModeValue int

const (
	autoColor consoleColorModeValue = iota
	disableColor
	forceColor
)

const (
	green   = "\033[97;42m"
	white   = "\033[90;47m"
	yellow  = "\033[90;43m"
	red     = "\033[97;41m"
	blue    = "\033[97;44m"
	magenta = "\033[97;45m"
	cyan    = "\033[97;46m"
	reset   = "\033[0m"
)

var consoleColorMode = autoColor

// LoggerConfig defines the config for Logger middleware.
type LoggerConfig struct {
	// Optional. Default value is gin.defaultLogFormatter
	Formatter LogFormatter

	// Output is a writer where logs are written.
	// Optional. Default value is gin.DefaultWriter.
	Output io.Writer

	// SkipPaths is a url path array which logs are not written.
	// Optional.
	SkipPaths []string
}

// LogFormatter gives the signature of the formatter function passed to LoggerWithFormatter
type LogFormatter func(params LogFormatterParams) string

// LogFormatterParams is the structure any formatter will be handed when time to log comes
type LogFormatterParams struct {
	Request *http.Request

	// TimeStamp shows the time after the server returns a response.
	TimeStamp time.Time
	// StatusCode is HTTP response code.
	StatusCode int
	// Latency is how much time the server cost to process a certain request.
	Latency time.Duration
	// ClientIP equals Context's ClientIP method.
	ClientIP string
	// Method is the HTTP method given to the request.
	Method string
	// Path is a path the client requests.
	Path string
	// ErrorMessage is set if error has occurred in processing the request.
	ErrorMessage string
	// isTerm shows whether does gin's output descriptor refers to a terminal.
	isTerm bool
	// BodySize is the size of the Response Body
	BodySize int
	// Keys are the keys set on the request's context.
	Keys map[string]interface{}
}

// StatusCodeColor is the ANSI color for appropriately logging http status code to a terminal.
func (p *LogFormatterParams) StatusCodeColor() string {
	code := p.StatusCode

	switch {
	case code >= http.StatusOK && code < http.StatusMultipleChoices:
		return green
	case code >= http.StatusMultipleChoices && code < http.StatusBadRequest:
		return white
	case code >= http.StatusBadRequest && code < http.StatusInternalServerError:
		return yellow
	default:
		return red
	}
}

// MethodColor is the ANSI color for appropriately logging http method to a terminal.
func (p *LogFormatterParams) MethodColor() string {
	method := p.Method

	switch method {
	case http.MethodGet:
		return blue
	case http.MethodPost:
		return cyan
	case http.MethodPut:
		return yellow
	case http.MethodDelete:
		return red
	case http.MethodPatch:
		return green
	case http.MethodHead:
		return magenta
	case http.MethodOptions:
		return white
	default:
		return reset
	}
}

// ResetColor resets all escape attributes.
func (p *LogFormatterParams) ResetColor() string {
	return reset
}

// IsOutputColor indicates whether can colors be outputted to the log.
func (p *LogFormatterParams) IsOutputColor() bool {
	return consoleColorMode == forceColor || (consoleColorMode == autoColor && p.isTerm)
}

// defaultLogFormatter is the default log format function Logger middleware uses.
var defaultLogFormatter = func(param LogFormatterParams) string {
	var statusColor, methodColor, resetColor string
	if param.IsOutputColor() {
		statusColor = param.StatusCodeColor()
		methodColor = param.MethodColor()
		resetColor = param.ResetColor()
	}

	if param.Latency > time.Minute {
		// Truncate in a golang < 1.8 safe way
		param.Latency = param.Latency - param.Latency%time.Second
	}
	return fmt.Sprintf("[GIN] %v |%s %3d %s| %13v | %15s |%s %-7s %s %#v\n%s",
		param.TimeStamp.Format("2006/01/02 - 15:04:05"),
		statusColor, param.StatusCode, resetColor,
		param.Latency,
		param.ClientIP,
		methodColor, param.Method, resetColor,
		param.Path,
		param.ErrorMessage,
	)
}

// DisableConsoleColor disables color output in the console.
func DisableConsoleColor() {
	consoleColorMode = disableColor
}

// ForceConsoleColor force color output in the console.
func ForceConsoleColor() {
	consoleColorMode = forceColor
}

// ErrorLogger returns a handlerfunc for any error type.
func ErrorLogger() HandlerFunc {
	return ErrorLoggerT(ErrorTypeAny)
}

// ErrorLoggerT returns a handlerfunc for a given error type.
func ErrorLoggerT(typ ErrorType) HandlerFunc {
	return func(c *Context) {
		c.Next()
		errors := c.Errors.ByType(typ)
		if len(errors) > 0 {
			c.JSON(-1, errors)
		}
	}
}

// Logger instances a Logger middleware that will write the logs to gin.DefaultWriter.
// By default gin.DefaultWriter = os.Stdout.
func Logger() HandlerFunc {
	return LoggerWithConfig(LoggerConfig{})
}

// LoggerWithFormatter instance a Logger middleware with the specified log format function.
func LoggerWithFormatter(f LogFormatter) HandlerFunc {
	return LoggerWithConfig(LoggerConfig{
		Formatter: f,
	})
}

// LoggerWithWriter instance a Logger middleware with the specified writer buffer.
// Example: os.Stdout, a file opened in write mode, a socket...
func LoggerWithWriter(out io.Writer, notlogged ...string) HandlerFunc {
	return LoggerWithConfig(LoggerConfig{
		Output:    out,
		SkipPaths: notlogged,
	})
}

// LoggerWithConfig instance a Logger middleware with config.
func LoggerWithConfig(conf LoggerConfig) HandlerFunc {
	formatter := conf.Formatter
	if formatter == nil {
		formatter = defaultLogFormatter
	}

	out := conf.Output
	if out == nil {
		out = DefaultWriter
	}

	notlogged := conf.SkipPaths

	isTerm := true

	if w, ok := out.(*os.File); !ok || os.Getenv("TERM") == "dumb" ||
		(!isatty.IsTerminal(w.Fd()) && !isatty.IsCygwinTerminal(w.Fd())) {
		isTerm = false
	}

	var skip map[string]struct{}

	if length := len(notlogged); length > 0 {
		skip = make(map[string]struct{}, length)

		for _, path := range notlogged {
			skip[path] = struct{}{}
		}
	}

	return func(c *Context) {
		// Start timer
		start := time.Now()
		path := c.Request.URL.Path
		raw := c.Request.URL.RawQuery

		// Process request
		c.Next()

		// Log only when path is not being skipped
		if _, ok := skip[path]; !ok {
			param := LogFormatterParams{
				Request: c.Request,
				isTerm:  isTerm,
				Keys:    c.Keys,
			}

			// Stop timer
			param.TimeStamp = time.Now()
			param.Latency = param.TimeStamp.Sub(start)

			param.ClientIP = c.ClientIP()
			param.Method = c.Request.Method
			param.StatusCode = c.Writer.Status()
			param.ErrorMessage = c.Errors.ByType(ErrorTypePrivate).String()

			param.BodySize = c.Writer.Size()

			if raw != "" {
				path = path + "?" + raw
			}

			param.Path = path

			fmt.Fprint(out, formatter(param))
		}
	}
}

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1		// Copyright 2014 Manu Martinez-Almeida. All rights reserved.
2		// Use of this source code is governed by a MIT style
3		// license that can be found in the LICENSE file.
4
5		package gin
6
7		import (
8		"fmt"
9		"io"
10		"net/http"
11		"os"
12		"time"
13
14		"github.com/mattn/go-isatty"
15		)
16
17		type consoleColorModeValue int
18
19		const (
20		autoColor consoleColorModeValue = iota
21		disableColor
22		forceColor
23		)
24
25		const (
26		green = "\033[97;42m"
27		white = "\033[90;47m"
28		yellow = "\033[90;43m"
29		red = "\033[97;41m"
30		blue = "\033[97;44m"
31		magenta = "\033[97;45m"
32		cyan = "\033[97;46m"
33		reset = "\033[0m"
34		)
35
36		var consoleColorMode = autoColor
37
38		// LoggerConfig defines the config for Logger middleware.
39		type LoggerConfig struct {
40		// Optional. Default value is gin.defaultLogFormatter
41		Formatter LogFormatter
42
43		// Output is a writer where logs are written.
44		// Optional. Default value is gin.DefaultWriter.
45		Output io.Writer
46
47		// SkipPaths is a url path array which logs are not written.
48		// Optional.
49		SkipPaths []string
50		}
51
52		// LogFormatter gives the signature of the formatter function passed to LoggerWithFormatter
53		type LogFormatter func(params LogFormatterParams) string
54
55		// LogFormatterParams is the structure any formatter will be handed when time to log comes
56		type LogFormatterParams struct {
57		Request *http.Request
58
59		// TimeStamp shows the time after the server returns a response.
60		TimeStamp time.Time
61		// StatusCode is HTTP response code.
62		StatusCode int
63		// Latency is how much time the server cost to process a certain request.
64		Latency time.Duration
65		// ClientIP equals Context's ClientIP method.
66		ClientIP string
67		// Method is the HTTP method given to the request.
68		Method string
69		// Path is a path the client requests.
70		Path string
71		// ErrorMessage is set if error has occurred in processing the request.
72		ErrorMessage string
73		// isTerm shows whether does gin's output descriptor refers to a terminal.
74		isTerm bool
75		// BodySize is the size of the Response Body
76		BodySize int
77		// Keys are the keys set on the request's context.
78		Keys map[string]interface{}
79		}
80
81		// StatusCodeColor is the ANSI color for appropriately logging http status code to a terminal.
82		func (p *LogFormatterParams) StatusCodeColor() string {
83	14	code := p.StatusCode
84
85	14	switch {
86	14	case code >= http.StatusOK && code < http.StatusMultipleChoices:
87	14	return green
88	14	case code >= http.StatusMultipleChoices && code < http.StatusBadRequest:
89	14	return white
90	14	case code >= http.StatusBadRequest && code < http.StatusInternalServerError:
91	14	return yellow
92	14	default:
93	14	return red
94		}
95		}
96
97		// MethodColor is the ANSI color for appropriately logging http method to a terminal.
98		func (p *LogFormatterParams) MethodColor() string {
99	14	method := p.Method
100
101	14	switch method {
102	14	case http.MethodGet:
103	14	return blue
104	14	case http.MethodPost:
105	14	return cyan
106	14	case http.MethodPut:
107	14	return yellow
108	14	case http.MethodDelete:
109	14	return red
110	14	case http.MethodPatch:
111	14	return green
112	14	case http.MethodHead:
113	14	return magenta
114	14	case http.MethodOptions:
115	14	return white
116	14	default:
117	14	return reset
118		}
119		}
120
121		// ResetColor resets all escape attributes.
122		func (p *LogFormatterParams) ResetColor() string {
123	14	return reset
124		}
125
126		// IsOutputColor indicates whether can colors be outputted to the log.
127		func (p *LogFormatterParams) IsOutputColor() bool {
128	14	return consoleColorMode == forceColor \|\| (consoleColorMode == autoColor && p.isTerm)
129		}
130
131		// defaultLogFormatter is the default log format function Logger middleware uses.
132	14	var defaultLogFormatter = func(param LogFormatterParams) string {
133	14	var statusColor, methodColor, resetColor string
134	14	if param.IsOutputColor() {
135	14	statusColor = param.StatusCodeColor()
136	14	methodColor = param.MethodColor()
137	14	resetColor = param.ResetColor()
138		}
139
140	14	if param.Latency > time.Minute {
141		// Truncate in a golang < 1.8 safe way
142	14	param.Latency = param.Latency - param.Latency%time.Second
143		}
144	14	return fmt.Sprintf("[GIN] %v \|%s %3d %s\| %13v \| %15s \|%s %-7s %s %#v\n%s",
145	14	param.TimeStamp.Format("2006/01/02 - 15:04:05"),
146	14	statusColor, param.StatusCode, resetColor,
147	14	param.Latency,
148	14	param.ClientIP,
149	14	methodColor, param.Method, resetColor,
150	14	param.Path,
151	14	param.ErrorMessage,
152	14	)
153		}
154
155		// DisableConsoleColor disables color output in the console.
156		func DisableConsoleColor() {
157	14	consoleColorMode = disableColor
158		}
159
160		// ForceConsoleColor force color output in the console.
161		func ForceConsoleColor() {
162	14	consoleColorMode = forceColor
163		}
164
165		// ErrorLogger returns a handlerfunc for any error type.
166		func ErrorLogger() HandlerFunc {
167	14	return ErrorLoggerT(ErrorTypeAny)
168		}
169
170		// ErrorLoggerT returns a handlerfunc for a given error type.
171		func ErrorLoggerT(typ ErrorType) HandlerFunc {
172	14	return func(c *Context) {
173	14	c.Next()
174	14	errors := c.Errors.ByType(typ)
175	14	if len(errors) > 0 {
176	14	c.JSON(-1, errors)
177		}
178		}
179		}
180
181		// Logger instances a Logger middleware that will write the logs to gin.DefaultWriter.
182		// By default gin.DefaultWriter = os.Stdout.
183		func Logger() HandlerFunc {
184	14	return LoggerWithConfig(LoggerConfig{})
185		}
186
187		// LoggerWithFormatter instance a Logger middleware with the specified log format function.
188		func LoggerWithFormatter(f LogFormatter) HandlerFunc {
189	14	return LoggerWithConfig(LoggerConfig{
190	14	Formatter: f,
191	14	})
192		}
193
194		// LoggerWithWriter instance a Logger middleware with the specified writer buffer.
195		// Example: os.Stdout, a file opened in write mode, a socket...
196		func LoggerWithWriter(out io.Writer, notlogged ...string) HandlerFunc {
197	14	return LoggerWithConfig(LoggerConfig{
198	14	Output: out,
199	14	SkipPaths: notlogged,
200	14	})
201		}
202
203		// LoggerWithConfig instance a Logger middleware with config.
204		func LoggerWithConfig(conf LoggerConfig) HandlerFunc {
205	14	formatter := conf.Formatter
206	14	if formatter == nil {
207	14	formatter = defaultLogFormatter
208		}
209
210	14	out := conf.Output
211	14	if out == nil {
212	14	out = DefaultWriter
213		}
214
215	14	notlogged := conf.SkipPaths
216
217	14	isTerm := true
218
219	14	if w, ok := out.(*os.File); !ok \|\| os.Getenv("TERM") == "dumb" \|\|
220	14	(!isatty.IsTerminal(w.Fd()) && !isatty.IsCygwinTerminal(w.Fd())) {
221	14	isTerm = false
222		}
223
224	14	var skip map[string]struct{}
225
226	14	if length := len(notlogged); length > 0 {
227	14	skip = make(map[string]struct{}, length)
228
229		for _, path := range notlogged {
230	14	skip[path] = struct{}{}
231		}
232		}
233
234	14	return func(c *Context) {
235		// Start timer
236	14	start := time.Now()
237	14	path := c.Request.URL.Path
238	14	raw := c.Request.URL.RawQuery
239
240		// Process request
241	14	c.Next()
242
243		// Log only when path is not being skipped
244	14	if _, ok := skip[path]; !ok {
245	14	param := LogFormatterParams{
246	14	Request: c.Request,
247	14	isTerm: isTerm,
248	14	Keys: c.Keys,
249		}
250
251		// Stop timer
252	14	param.TimeStamp = time.Now()
253	14	param.Latency = param.TimeStamp.Sub(start)
254
255	14	param.ClientIP = c.ClientIP()
256	14	param.Method = c.Request.Method
257	14	param.StatusCode = c.Writer.Status()
258	14	param.ErrorMessage = c.Errors.ByType(ErrorTypePrivate).String()
259
260	14	param.BodySize = c.Writer.Size()
261
262	14	if raw != "" {
263	14	path = path + "?" + raw
264		}
265
266	14	param.Path = path
267
268	14	fmt.Fprint(out, formatter(param))
269		}
270		}
271		}