README
¶
OpenTelemetry handler
log/slog handler attaching OpenTelemetry trace details to logs.
Installation
go get github.com/go-slog/otelslog
Usage
Wrap an existing handler:
import(
"log/slog"
"github.com/go-slog/otelslog"
)
var handler slog.Handler
// Set up your handler
// handler = ...
// Wrap Handler
handler = otelslog.NewHandler(handler)
logger := slog.New(handler)
// Call logger with a context
logger.InfoContext(ctx, "hello world")
// Output: level=INFO msg="hello world" trace_id=74726163655f69645f74657374313233 span_id=7370616e5f696431
Use it as a middleware in slogmulti.Pipe:
import (
"github.com/go-slog/otelslog"
"github.com/samber/slog-multi"
)
handler = slogmulti.Pipe(otelslog.Middleware()).Handler(handler)
// Set p logger
// ...
Development
Run tests:
go test -race -v ./...
Run linter:
golangci-lint run
License
The project is licensed under the MIT License.
Documentation
¶
Overview ¶
Package otelslog provides an slog.Handler that attaches OpenTelemetry trace details to logs.
Package otelslog provides an slog.Handler that attaches OpenTelemetry trace details to logs.
Index ¶
Examples ¶
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func Middleware ¶
Middleware returns a Middleware for an slogmulti.Pipe handler.
func NewHandler ¶
NewHandler returns a new Handler.
func WithResource ¶ added in v0.1.0
WithResource returns an slog.Logger with all attributes attached from a resource.Resource.
Example ¶
// Set up handler
handler := testHandler()
// Set up logger
logger := slog.New(handler)
res, _ := resource.New(
context.Background(),
resource.WithAttributes(
attribute.String("service.name", "my-service"),
attribute.String("service.version", "1.0.0"),
attribute.Bool("debug", false),
attribute.Float64("sampling", 0.6),
),
)
// Attach resource details to logger
logger = otelslog.WithResource(logger, res)
// Call logger
logger.Info("hello world")
Output: time=0001-01-01T00:00:00.000Z level=INFO msg="hello world" debug=false sampling=0.6 service.name=my-service service.version=1.0.0
Types ¶
type Handler ¶
Handler attaches details from an OpenTelemetry trace to each log record.
Example ¶
package main
import (
"context"
"log/slog"
"os"
"time"
"go.opentelemetry.io/otel/trace"
"github.com/go-slog/otelslog"
)
func testHandler() slog.Handler {
return slog.NewTextHandler(os.Stdout, &slog.HandlerOptions{
AddSource: false,
Level: nil,
ReplaceAttr: func(_ []string, a slog.Attr) slog.Attr {
if a.Key == slog.TimeKey {
a.Value = slog.TimeValue(time.Time{})
}
return a
},
})
}
func testContext() context.Context {
ctx := context.Background()
spanContext := trace.NewSpanContext(trace.SpanContextConfig{
TraceID: [16]byte{116, 114, 97, 99, 101, 95, 105, 100, 95, 116, 101, 115, 116, 49, 50, 51},
SpanID: [8]byte{115, 112, 97, 110, 95, 105, 100, 49},
})
ctx = trace.ContextWithSpanContext(ctx, spanContext)
return ctx
}
func main() {
var handler slog.Handler
// Set up handler
handler = testHandler()
// Wrap handler
handler = otelslog.NewHandler(handler)
// Set up logger
logger := slog.New(handler)
// later in some trace context (eg. http request)
ctx := testContext()
// Call logger with a context
logger.InfoContext(ctx, "hello world")
}
Output: time=0001-01-01T00:00:00.000Z level=INFO msg="hello world" trace_id=74726163655f69645f74657374313233 span_id=7370616e5f696431
func (Handler) Handle ¶
Handle implements slog.Handler.
func (Handler) WithAttrs ¶
WithAttrs implements slog.Handler.
Source Files