slog: Echo middleware
Echo middleware to log http requests using slog.
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Simple to use, built on open standards, and designed for full cost control
Simple to use, built on open standards, and designed for full cost control
See also:
- slog-multi:
slog.Handlerchaining, fanout, routing, failover, load balancing... - slog-formatter:
slogattribute formatting - slog-sampling:
slogsampling policy - slog-mock:
slog.Handlerfor test purposes
HTTP middlewares:
- slog-gin: Gin middleware for
sloglogger - slog-echo: Echo middleware for
sloglogger - slog-fiber: Fiber middleware for
sloglogger - slog-chi: Chi middleware for
sloglogger - slog-http:
net/httpmiddleware forsloglogger
Loggers:
- slog-zap: A
sloghandler forZap - slog-zerolog: A
sloghandler forZerolog - slog-logrus: A
sloghandler forLogrus
Log sinks:
- slog-datadog: A
sloghandler forDatadog - slog-betterstack: A
sloghandler forBetterstack - slog-rollbar: A
sloghandler forRollbar - slog-loki: A
sloghandler forLoki - slog-sentry: A
sloghandler forSentry - slog-syslog: A
sloghandler forSyslog - slog-logstash: A
sloghandler forLogstash - slog-fluentd: A
sloghandler forFluentd - slog-graylog: A
sloghandler forGraylog - slog-quickwit: A
sloghandler forQuickwit - slog-slack: A
sloghandler forSlack - slog-telegram: A
sloghandler forTelegram - slog-mattermost: A
sloghandler forMattermost - slog-microsoft-teams: A
sloghandler forMicrosoft Teams - slog-webhook: A
sloghandler forWebhook - slog-kafka: A
sloghandler forKafka - slog-nats: A
sloghandler forNATS - slog-parquet: A
sloghandler forParquet+Object Storage - slog-channel: A
sloghandler for Go channels
Install
# echo v4 (current)
go get github.com/samber/slog-echo
# echo v5 (alpha)
go get github.com/samber/slog-echo@echo-v5
go get github.com/samber/slog-echo
# echo v5 (alpha)
go get github.com/samber/slog-echo@echo-v5
Compatibility: go >= 1.21
No breaking changes will be made to exported APIs before v2.0.0.
Usage
Handler options
type Config struct {
DefaultLevel slog.Level
ClientErrorLevel slog.Level
ServerErrorLevel slog.Level
WithUserAgent bool
WithRequestID bool
WithRequestBody bool
WithRequestHeader bool
WithResponseBody bool
WithResponseHeader bool
WithSpanID bool
WithTraceID bool
WithClientIP bool
WithCustomMessage func(c echo.Context, err error) string
Filters []Filter
}
DefaultLevel slog.Level
ClientErrorLevel slog.Level
ServerErrorLevel slog.Level
WithUserAgent bool
WithRequestID bool
WithRequestBody bool
WithRequestHeader bool
WithResponseBody bool
WithResponseHeader bool
WithSpanID bool
WithTraceID bool
WithClientIP bool
WithCustomMessage func(c echo.Context, err error) string
Filters []Filter
}
Attributes will be injected in log payload.
Other global parameters:
slogecho.TraceIDKey = "trace_id"
slogecho.SpanIDKey = "span_id"
slogecho.RequestBodyMaxSize = 64 * 1024 // 64KB
slogecho.ResponseBodyMaxSize = 64 * 1024 // 64KB
slogecho.HiddenRequestHeaders = map[string]struct{}{ ... }
slogecho.HiddenResponseHeaders = map[string]struct{}{ ... }
slogecho.SpanIDKey = "span_id"
slogecho.RequestBodyMaxSize = 64 * 1024 // 64KB
slogecho.ResponseBodyMaxSize = 64 * 1024 // 64KB
slogecho.HiddenRequestHeaders = map[string]struct{}{ ... }
slogecho.HiddenResponseHeaders = map[string]struct{}{ ... }
Minimal
import (
"net/http"
"os"
"time"
"github.com/labstack/echo/v4"
"github.com/labstack/echo/v4/middleware"
slogecho "github.com/samber/slog-echo"
"log/slog"
)
// Create a slog logger, which:
// - Logs to stdout.
logger := slog.New(slog.NewTextHandler(os.Stdout, nil))
// Echo instance
e := echo.New()
// Middleware
e.Use(slogecho.New(logger))
e.Use(middleware.Recover())
// Routes
e.GET("/", func(c echo.Context) error {
return c.String(http.StatusOK, "Hello, World!")
})
e.GET("/error", func(c echo.Context) error {
return echo.
NewHTTPError(http.StatusInternalServerError, "I'm angry").
WithInternal(errors.New("I'm angry internally"))
})
// Start server
e.Logger.Fatal(e.Start(":4242"))
// output:
// time=2023-10-15T20:32:58.926+02:00 level=INFO msg="Success" env=production request.time=2023-10-15T20:32:58.626+02:00 request.method=GET request.path=/ request.route="" request.ip=127.0.0.1:63932 request.length=0 response.time=2023-10-15T20:32:58.926+02:00 response.latency=100ms response.status=200 response.length=7 id=229c7fc8-64f5-4467-bc4a-940700503b0d http.error="map[code:500 internal:I'm angry internally message:I'm angry]" http.internal="I'm angry internally"
"net/http"
"os"
"time"
"github.com/labstack/echo/v4"
"github.com/labstack/echo/v4/middleware"
slogecho "github.com/samber/slog-echo"
"log/slog"
)
// Create a slog logger, which:
// - Logs to stdout.
logger := slog.New(slog.NewTextHandler(os.Stdout, nil))
// Echo instance
e := echo.New()
// Middleware
e.Use(slogecho.New(logger))
e.Use(middleware.Recover())
// Routes
e.GET("/", func(c echo.Context) error {
return c.String(http.StatusOK, "Hello, World!")
})
e.GET("/error", func(c echo.Context) error {
return echo.
NewHTTPError(http.StatusInternalServerError, "I'm angry").
WithInternal(errors.New("I'm angry internally"))
})
// Start server
e.Logger.Fatal(e.Start(":4242"))
// output:
// time=2023-10-15T20:32:58.926+02:00 level=INFO msg="Success" env=production request.time=2023-10-15T20:32:58.626+02:00 request.method=GET request.path=/ request.route="" request.ip=127.0.0.1:63932 request.length=0 response.time=2023-10-15T20:32:58.926+02:00 response.latency=100ms response.status=200 response.length=7 id=229c7fc8-64f5-4467-bc4a-940700503b0d http.error="map[code:500 internal:I'm angry internally message:I'm angry]" http.internal="I'm angry internally"
OTEL
logger := slog.New(slog.NewTextHandler(os.Stdout, nil))
config := slogecho.Config{
WithSpanID: true,
WithTraceID: true,
}
e := echo.New()
e.Use(slogecho.NewWithConfig(logger, config))
e.Use(middleware.Recover())
config := slogecho.Config{
WithSpanID: true,
WithTraceID: true,
}
e := echo.New()
e.Use(slogecho.NewWithConfig(logger, config))
e.Use(middleware.Recover())
Custom log levels
logger := slog.New(slog.NewTextHandler(os.Stdout, nil))
config := slogecho.Config{
DefaultLevel: slog.LevelInfo,
ClientErrorLevel: slog.LevelWarn,
ServerErrorLevel: slog.LevelError,
}
e := echo.New()
e.Use(slogecho.NewWithConfig(logger, config))
e.Use(middleware.Recover())
config := slogecho.Config{
DefaultLevel: slog.LevelInfo,
ClientErrorLevel: slog.LevelWarn,
ServerErrorLevel: slog.LevelError,
}
e := echo.New()
e.Use(slogecho.NewWithConfig(logger, config))
e.Use(middleware.Recover())
Verbose
logger := slog.New(slog.NewTextHandler(os.Stdout, nil))
config := slogecho.Config{
WithRequestBody: true,
WithResponseBody: true,
WithRequestHeader: true,
WithResponseHeader: true,
}
e := echo.New()
e.Use(slogecho.NewWithConfig(logger, config))
e.Use(middleware.Recover())
config := slogecho.Config{
WithRequestBody: true,
WithResponseBody: true,
WithRequestHeader: true,
WithResponseHeader: true,
}
e := echo.New()
e.Use(slogecho.NewWithConfig(logger, config))
e.Use(middleware.Recover())
Filters
logger := slog.New(slog.NewTextHandler(os.Stdout, nil))
e := echo.New()
e.Use(
slogecho.NewWithFilters(
logger,
slogecho.Accept(func (c echo.Context) bool {
return xxx
}),
slogecho.IgnoreStatus(401, 404),
),
)
e.Use(middleware.Recover())
e := echo.New()
e.Use(
slogecho.NewWithFilters(
logger,
slogecho.Accept(func (c echo.Context) bool {
return xxx
}),
slogecho.IgnoreStatus(401, 404),
),
)
e.Use(middleware.Recover())
Available filters:
Filters
logger := slog.New(slog.NewTextHandler(os.Stdout, nil))
router := gin.New()
router.Use(
sloggin.NewWithFilters(
logger,
sloggin.Accept(func (c *gin.Context) bool {
return xxx
}),
sloggin.IgnoreStatus(401, 404),
),
)
router := gin.New()
router.Use(
sloggin.NewWithFilters(
logger,
sloggin.Accept(func (c *gin.Context) bool {
return xxx
}),
sloggin.IgnoreStatus(401, 404),
),
)
Available filters:
- Accept / Ignore
- AcceptMethod / IgnoreMethod
- AcceptStatus / IgnoreStatus
- AcceptStatusGreaterThan / IgnoreStatusGreaterThan
- AcceptStatusLessThan / IgnoreStatusLessThan
- AcceptStatusGreaterThanOrEqual / IgnoreStatusGreaterThanOrEqual
- AcceptStatusLessThanOrEqual / IgnoreStatusLessThanOrEqual
- AcceptPath / IgnorePath
- AcceptPathContains / IgnorePathContains
- AcceptPathPrefix / IgnorePathPrefix
- AcceptPathSuffix / IgnorePathSuffix
- AcceptPathMatch / IgnorePathMatch
- AcceptHost / IgnoreHost
- AcceptHostContains / IgnoreHostContains
- AcceptHostPrefix / IgnoreHostPrefix
- AcceptHostSuffix / IgnoreHostSuffix
- AcceptHostMatch / IgnoreHostMatch
Using custom time formatters
import (
"github.com/labstack/echo/v4"
"github.com/labstack/echo/v4/middleware"
slogecho "github.com/samber/slog-echo"
slogformatter "github.com/samber/slog-formatter"
"log/slog"
)
// Create a slog logger, which:
// - Logs to stdout.
// - RFC3339 with UTC time format.
logger := slog.New(
slogformatter.NewFormatterHandler(
slogformatter.TimezoneConverter(time.UTC),
slogformatter.TimeFormatter(time.DateTime, nil),
)(
slog.NewTextHandler(os.Stdout, nil),
),
)
// Echo instance
e := echo.New()
// Middleware
e.Use(slogecho.New(logger))
e.Use(middleware.Recover())
// Routes
e.GET("/", func(c echo.Context) error {
return c.String(http.StatusOK, "Hello, World!")
})
e.GET("/error", func(c echo.Context) error {
return echo.
NewHTTPError(http.StatusInternalServerError, "I'm angry").
WithInternal(errors.New("I'm angry internally"))
})
// Start server
e.Logger.Fatal(e.Start(":4242"))
// output:
// time=2023-10-15T20:32:58.926+02:00 level=INFO msg="Success" env=production request.time=2023-10-15T20:32:58Z request.method=GET request.path=/ request.route="" request.ip=127.0.0.1:63932 request.length=0 response.time=2023-10-15T20:32:58Z response.latency=100ms response.status=200 response.length=7 id=229c7fc8-64f5-4467-bc4a-940700503b0d error="map[code:500 internal:I'm angry internally message:I'm angry]" internal="I'm angry internally"
"github.com/labstack/echo/v4"
"github.com/labstack/echo/v4/middleware"
slogecho "github.com/samber/slog-echo"
slogformatter "github.com/samber/slog-formatter"
"log/slog"
)
// Create a slog logger, which:
// - Logs to stdout.
// - RFC3339 with UTC time format.
logger := slog.New(
slogformatter.NewFormatterHandler(
slogformatter.TimezoneConverter(time.UTC),
slogformatter.TimeFormatter(time.DateTime, nil),
)(
slog.NewTextHandler(os.Stdout, nil),
),
)
// Echo instance
e := echo.New()
// Middleware
e.Use(slogecho.New(logger))
e.Use(middleware.Recover())
// Routes
e.GET("/", func(c echo.Context) error {
return c.String(http.StatusOK, "Hello, World!")
})
e.GET("/error", func(c echo.Context) error {
return echo.
NewHTTPError(http.StatusInternalServerError, "I'm angry").
WithInternal(errors.New("I'm angry internally"))
})
// Start server
e.Logger.Fatal(e.Start(":4242"))
// output:
// time=2023-10-15T20:32:58.926+02:00 level=INFO msg="Success" env=production request.time=2023-10-15T20:32:58Z request.method=GET request.path=/ request.route="" request.ip=127.0.0.1:63932 request.length=0 response.time=2023-10-15T20:32:58Z response.latency=100ms response.status=200 response.length=7 id=229c7fc8-64f5-4467-bc4a-940700503b0d error="map[code:500 internal:I'm angry internally message:I'm angry]" internal="I'm angry internally"
Using custom logger sub-group
logger := slog.New(slog.NewTextHandler(os.Stdout, nil))
// Echo instance
e := echo.New()
// Middleware
e.Use(slogecho.New(logger.WithGroup("http")))
e.Use(middleware.Recover())
// Routes
e.GET("/", func(c echo.Context) error {
return c.String(http.StatusOK, "Hello, World!")
})
e.GET("/error", func(c echo.Context) error {
return echo.
NewHTTPError(http.StatusInternalServerError, "I'm angry").
WithInternal(errors.New("I'm angry internally"))
})
// Start server
e.Logger.Fatal(e.Start(":4242"))
// output:
// time=2023-10-15T20:32:58.926+02:00 level=INFO msg="Success" env=production http.request.time=2023-10-15T20:32:58.626+02:00 http.request.method=GET http.request.path=/ http.request.route="" http.request.ip=127.0.0.1:63932 http.request.length=0 http.response.time=2023-10-15T20:32:58.926+02:00 http.response.latency=100ms http.response.status=200 http.response.length=7 http.id=229c7fc8-64f5-4467-bc4a-940700503b0d http.error="map[code:500 internal:I'm angry internally message:I'm angry]" http.internal="I'm angry internally"
// Echo instance
e := echo.New()
// Middleware
e.Use(slogecho.New(logger.WithGroup("http")))
e.Use(middleware.Recover())
// Routes
e.GET("/", func(c echo.Context) error {
return c.String(http.StatusOK, "Hello, World!")
})
e.GET("/error", func(c echo.Context) error {
return echo.
NewHTTPError(http.StatusInternalServerError, "I'm angry").
WithInternal(errors.New("I'm angry internally"))
})
// Start server
e.Logger.Fatal(e.Start(":4242"))
// output:
// time=2023-10-15T20:32:58.926+02:00 level=INFO msg="Success" env=production http.request.time=2023-10-15T20:32:58.626+02:00 http.request.method=GET http.request.path=/ http.request.route="" http.request.ip=127.0.0.1:63932 http.request.length=0 http.response.time=2023-10-15T20:32:58.926+02:00 http.response.latency=100ms http.response.status=200 http.response.length=7 http.id=229c7fc8-64f5-4467-bc4a-940700503b0d http.error="map[code:500 internal:I'm angry internally message:I'm angry]" http.internal="I'm angry internally"
Add logger to a single route
logger := slog.New(slog.NewTextHandler(os.Stdout, nil))
// Echo instance
e := echo.New()
// Middleware
e.Use(middleware.Recover())
// Routes
e.GET("/", func(c echo.Context) error {
return c.String(http.StatusOK, "Hello, World!")
}, slogecho.New(logger))
// Start server
e.Logger.Fatal(e.Start(":4242"))
// Echo instance
e := echo.New()
// Middleware
e.Use(middleware.Recover())
// Routes
e.GET("/", func(c echo.Context) error {
return c.String(http.StatusOK, "Hello, World!")
}, slogecho.New(logger))
// Start server
e.Logger.Fatal(e.Start(":4242"))
Adding custom attributes
logger := slog.New(slog.NewTextHandler(os.Stdout, nil))
// Add an attribute to all log entries made through this logger.
logger = logger.With("env", "production")
// Echo instance
e := echo.New()
// Middleware
e.Use(slogecho.New(logger))
e.Use(middleware.Recover())
// Routes
e.GET("/", func(c echo.Context) error {
// Add an attribute to a single log entry.
slogecho.AddCustomAttributes(c, slog.String("foo", "bar"))
return c.String(http.StatusOK, "Hello, World!")
})
// Start server
e.Logger.Fatal(e.Start(":4242"))
// output:
// time=2023-10-15T20:32:58.926+02:00 level=INFO msg="Success" env=production request.time=2023-10-15T20:32:58.626+02:00 request.method=GET request.path=/ request.route="" request.ip=127.0.0.1:63932 request.length=0 response.time=2023-10-15T20:32:58.926+02:00 response.latency=100ms response.status=200 response.length=7 id=229c7fc8-64f5-4467-bc4a-940700503b0d foo=bar error="map[code:500 internal:I'm angry internally message:I'm angry]" internal="I'm angry internally"
// Add an attribute to all log entries made through this logger.
logger = logger.With("env", "production")
// Echo instance
e := echo.New()
// Middleware
e.Use(slogecho.New(logger))
e.Use(middleware.Recover())
// Routes
e.GET("/", func(c echo.Context) error {
// Add an attribute to a single log entry.
slogecho.AddCustomAttributes(c, slog.String("foo", "bar"))
return c.String(http.StatusOK, "Hello, World!")
})
// Start server
e.Logger.Fatal(e.Start(":4242"))
// output:
// time=2023-10-15T20:32:58.926+02:00 level=INFO msg="Success" env=production request.time=2023-10-15T20:32:58.626+02:00 request.method=GET request.path=/ request.route="" request.ip=127.0.0.1:63932 request.length=0 response.time=2023-10-15T20:32:58.926+02:00 response.latency=100ms response.status=200 response.length=7 id=229c7fc8-64f5-4467-bc4a-940700503b0d foo=bar error="map[code:500 internal:I'm angry internally message:I'm angry]" internal="I'm angry internally"
JSON output
logger := slog.New(slog.NewJSONHandler(os.Stdout, nil))
// Echo instance
e := echo.New()
// Middleware
e.Use(slogecho.New(logger))
e.Use(middleware.Recover())
// Routes
e.GET("/", func(c echo.Context) error {
return c.String(http.StatusOK, "Hello, World!")
})
// Start server
e.Logger.Fatal(e.Start(":4242"))
// output:
// {"time":"2023-10-15T20:32:58.926+02:00","level":"INFO","msg" :"Success","env":"production","http":{"request":{"time":"202 3-10-15T20:32:58.626+02:00","method":"GET","path":"/","route ":"","ip":"127.0.0.1:55296","length":0},"response":{"time":" 2023-10-15T20:32:58.926+02:00","latency":100000,"status":200 ,"length":7},"id":"04201917-d7ba-4b20-a3bb-2fffba5f2bd9"}, "error": {"code":500, "internal":"I'm angry internally", "message":"I'm angry"}, "internal": "I'm angry internally"}
// Echo instance
e := echo.New()
// Middleware
e.Use(slogecho.New(logger))
e.Use(middleware.Recover())
// Routes
e.GET("/", func(c echo.Context) error {
return c.String(http.StatusOK, "Hello, World!")
})
// Start server
e.Logger.Fatal(e.Start(":4242"))
// output:
// {"time":"2023-10-15T20:32:58.926+02:00","level":"INFO","msg" :"Success","env":"production","http":{"request":{"time":"202 3-10-15T20:32:58.626+02:00","method":"GET","path":"/","route ":"","ip":"127.0.0.1:55296","length":0},"response":{"time":" 2023-10-15T20:32:58.926+02:00","latency":100000,"status":200 ,"length":7},"id":"04201917-d7ba-4b20-a3bb-2fffba5f2bd9"}, "error": {"code":500, "internal":"I'm angry internally", "message":"I'm angry"}, "internal": "I'm angry internally"}
Contributing
- Ping me on Twitter @samuelberthe (DMs, mentions, whatever :))
- Fork the project
- Fix open issues or request new features
Don't hesitate ;)
# Install some dev dependencies
make tools
# Run tests
make test
# or
make watch-test
make tools
# Run tests
make test
# or
make watch-test
Contributors
Show your support
Give a if this project helped you!
License
Copyright (c) 2023 Samuel Berthe.
This project is MIT licensed.