https://github.com/samber/slog-echo
🚨 Echo middleware for slog logger
https://github.com/samber/slog-echo
attribute echo echo-framework error errors go golang handler http log log-level logger middleware slog structured-logging
Last synced: 9 months ago
JSON representation
🚨 Echo middleware for slog logger
- Host: GitHub
- URL: https://github.com/samber/slog-echo
- Owner: samber
- License: mit
- Created: 2023-04-30T18:16:38.000Z (over 2 years ago)
- Default Branch: main
- Last Pushed: 2025-03-25T10:57:16.000Z (9 months ago)
- Last Synced: 2025-03-29T14:11:21.066Z (9 months ago)
- Topics: attribute, echo, echo-framework, error, errors, go, golang, handler, http, log, log-level, logger, middleware, slog, structured-logging
- Language: Go
- Homepage: https://pkg.go.dev/github.com/samber/slog-echo
- Size: 139 KB
- Stars: 116
- Watchers: 3
- Forks: 14
- Open Issues: 1
-
Metadata Files:
- Readme: README.md
- Funding: .github/FUNDING.yml
- License: LICENSE
Awesome Lists containing this project
- awesome-slog - slog-echo
README
# slog: Echo middleware
[](https://github.com/samber/slog-echo/releases)

[](https://pkg.go.dev/github.com/samber/slog-echo)

[](https://goreportcard.com/report/github.com/samber/slog-echo)
[](https://codecov.io/gh/samber/slog-echo)
[](https://github.com/samber/slog-echo/graphs/contributors)
[](./LICENSE)
[Echo](https://github.com/labstack/echo) middleware to log http requests using [slog](https://pkg.go.dev/log/slog).
Sponsored by:
Cloud-native search engine for observability - An OSS alternative to Splunk, Elasticsearch, Loki, and Tempo.
**See also:**
- [slog-multi](https://github.com/samber/slog-multi): `slog.Handler` chaining, fanout, routing, failover, load balancing...
- [slog-formatter](https://github.com/samber/slog-formatter): `slog` attribute formatting
- [slog-sampling](https://github.com/samber/slog-sampling): `slog` sampling policy
- [slog-mock](https://github.com/samber/slog-mock): `slog.Handler` for test purposes
**HTTP middlewares:**
- [slog-gin](https://github.com/samber/slog-gin): Gin middleware for `slog` logger
- [slog-echo](https://github.com/samber/slog-echo): Echo middleware for `slog` logger
- [slog-fiber](https://github.com/samber/slog-fiber): Fiber middleware for `slog` logger
- [slog-chi](https://github.com/samber/slog-chi): Chi middleware for `slog` logger
- [slog-http](https://github.com/samber/slog-http): `net/http` middleware for `slog` logger
**Loggers:**
- [slog-zap](https://github.com/samber/slog-zap): A `slog` handler for `Zap`
- [slog-zerolog](https://github.com/samber/slog-zerolog): A `slog` handler for `Zerolog`
- [slog-logrus](https://github.com/samber/slog-logrus): A `slog` handler for `Logrus`
**Log sinks:**
- [slog-datadog](https://github.com/samber/slog-datadog): A `slog` handler for `Datadog`
- [slog-betterstack](https://github.com/samber/slog-betterstack): A `slog` handler for `Betterstack`
- [slog-rollbar](https://github.com/samber/slog-rollbar): A `slog` handler for `Rollbar`
- [slog-loki](https://github.com/samber/slog-loki): A `slog` handler for `Loki`
- [slog-sentry](https://github.com/samber/slog-sentry): A `slog` handler for `Sentry`
- [slog-syslog](https://github.com/samber/slog-syslog): A `slog` handler for `Syslog`
- [slog-logstash](https://github.com/samber/slog-logstash): A `slog` handler for `Logstash`
- [slog-fluentd](https://github.com/samber/slog-fluentd): A `slog` handler for `Fluentd`
- [slog-graylog](https://github.com/samber/slog-graylog): A `slog` handler for `Graylog`
- [slog-quickwit](https://github.com/samber/slog-quickwit): A `slog` handler for `Quickwit`
- [slog-slack](https://github.com/samber/slog-slack): A `slog` handler for `Slack`
- [slog-telegram](https://github.com/samber/slog-telegram): A `slog` handler for `Telegram`
- [slog-mattermost](https://github.com/samber/slog-mattermost): A `slog` handler for `Mattermost`
- [slog-microsoft-teams](https://github.com/samber/slog-microsoft-teams): A `slog` handler for `Microsoft Teams`
- [slog-webhook](https://github.com/samber/slog-webhook): A `slog` handler for `Webhook`
- [slog-kafka](https://github.com/samber/slog-kafka): A `slog` handler for `Kafka`
- [slog-nats](https://github.com/samber/slog-nats): A `slog` handler for `NATS`
- [slog-parquet](https://github.com/samber/slog-parquet): A `slog` handler for `Parquet` + `Object Storage`
- [slog-channel](https://github.com/samber/slog-channel): A `slog` handler for Go channels
## 🚀 Install
```sh
# echo v4 (current)
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
```go
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
Filters []Filter
}
```
Attributes will be injected in log payload.
Other global parameters:
```go
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{}{ ... }
```
### Minimal
```go
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"
```
### OTEL
```go
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())
```
### Custom log levels
```go
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())
```
### Verbose
```go
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())
```
### Filters
```go
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())
```
Available filters:
### Filters
```go
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),
),
)
```
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
```go
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"
```
### Using custom logger sub-group
```go
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"
```
### Add logger to a single route
```go
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"))
```
### Adding custom attributes
```go
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"
```
### JSON output
```go
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":"2023-10-15T20:32:58.626+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](https://twitter.com/samuelberthe) (DMs, mentions, whatever :))
- Fork the [project](https://github.com/samber/slog-echo)
- Fix [open issues](https://github.com/samber/slog-echo/issues) or request new features
Don't hesitate ;)
```bash
# Install some dev dependencies
make tools
# Run tests
make test
# or
make watch-test
```
## 👤 Contributors

## 💫 Show your support
Give a ⭐️ if this project helped you!
[](https://github.com/sponsors/samber)
## 📝 License
Copyright © 2023 [Samuel Berthe](https://github.com/samber).
This project is [MIT](./LICENSE) licensed.