Otelfiber

https://pkg.go.dev/github.com/gofiber/contrib/otelfiber/v2
Admin
Otelfiber is an OpenTelemetry middleware for the Fiber web framework that provides distributed...
Tokens:2,084
Snippets:28
Trust Score:9.6
Update:6 months ago
Show doc for...
Tokens:
Raw
### Install otelfiber Middleware

Source: https://pkg.go.dev/github.com/gofiber/contrib/otelfiber/v2

Use `go get` to install the otelfiber middleware for Fiber v2. Ensure you are using Go 1.19 or above.

```go
go get -u github.com/gofiber/contrib/otelfiber/v2
```

--------------------------------

### Full Fiber Application with otelfiber

Source: https://pkg.go.dev/github.com/gofiber/contrib/otelfiber/v2

This example demonstrates setting up a Fiber application with otelfiber middleware, including tracer initialization, custom routes, and error handling. It uses stdout exporter for tracing.

```go
package main

import (
	"context"
	"errors"
	"log"

	"go.opentelemetry.io/otel/sdk/resource"

	"github.com/gofiber/fiber/v2"

	"github.com/gofiber/contrib/otelfiber"
	"go.opentelemetry.io/otel"
	"go.opentelemetry.io/otel/attribute"
	stdout "go.opentelemetry.io/otel/exporters/stdout/stdouttrace"

	"go.opentelemetry.io/otel/propagation"
	sdktrace "go.opentelemetry.io/otel/sdk/trace"
	semconv "go.opentelemetry.io/otel/semconv/v1.4.0"
	oteltrace "go.opentelemetry.io/otel/trace"
)

var tracer = otel.Tracer("fiber-server")

func main() {
	tp := initTracer()
	defer func() {
		if err := tp.Shutdown(context.Background()); err != nil {
			log.Printf("Error shutting down tracer provider: %v", err)
		}
	}()

	app := fiber.New()

	app.Use(otelfiber.Middleware())

	app.Get("/error", func(ctx *fiber.Ctx) error {
		return errors.New("abc")
	})

	app.Get("/users/:id", func(c *fiber.Ctx) error {
		id := c.Params("id")
		name := getUser(c.UserContext(), id)
		return c.JSON(fiber.Map{"id": id, name: name})
	})

	log.Fatal(app.Listen(":3000"))
}

func initTracer() *sdktrace.TracerProvider {
	exporter, err := stdout.New(stdout.WithPrettyPrint())
	if err != nil {
		log.Fatal(err)
	}
	tp := sdktrace.NewTracerProvider(
		sdktrace.WithSampler(sdktrace.AlwaysSample()),
		sdktrace.WithBatcher(exporter),
		sdktrace.WithResource(
			resource.NewWithAttributes(
				semconv.SchemaURL,
				semconv.ServiceNameKey.String("my-service"),
			)),
	)
	otel.SetTracerProvider(tp)
	otel.SetTextMapPropagator(propagation.NewCompositeTextMapPropagator(propagation.TraceContext{}, propagation.Baggage{}))
	return tp
}

func getUser(ctx context.Context, id string) string {
	_, span := tracer.Start(ctx, "getUser", oteltrace.WithAttributes(attribute.String("id", id)))
	defer span.End()
	if id == "123" {
		return "otelfiber tester"
	}
	return "unknown"
}

```

--------------------------------

### Define configuration options

Source: https://pkg.go.dev/github.com/gofiber/contrib/otelfiber/v2

Functions to configure the behavior of the otelfiber middleware, including providers, attributes, and filtering.

```go
func WithCollectClientIP(collect bool) Option
```

```go
func WithCustomAttributes(f func(ctx *fiber.Ctx) []attribute.KeyValue) Option
```

```go
func WithCustomMetricAttributes(f func(ctx *fiber.Ctx) []attribute.KeyValue) Option
```

```go
func WithMeterProvider(provider otelmetric.MeterProvider) Option
```

```go
func WithNext(f func(ctx *fiber.Ctx) bool) Option
```

```go
func WithPort(port int) Option
```

```go
func WithPropagators(propagators propagation.TextMapPropagator) Option
```

```go
func WithSpanNameFormatter(f func(ctx *fiber.Ctx) string) Option
```

```go
func WithTracerProvider(provider oteltrace.TracerProvider) Option
```

```go
func WithoutMetrics(withoutMetrics bool) Option
```

--------------------------------

### Configuration Options

Source: https://pkg.go.dev/github.com/gofiber/contrib/otelfiber/v2

Available options to configure the otelfiber middleware behavior.

```APIDOC
## Configuration Options

### Description
Functions used to configure the behavior of the otelfiber middleware.

### Options
- **WithCollectClientIP** (bool) - Specifies whether to collect the client's IP address.
- **WithCustomAttributes** (func) - Adds custom attributes to the span.
- **WithCustomMetricAttributes** (func) - Adds custom attributes to metrics.
- **WithMeterProvider** (otelmetric.MeterProvider) - Sets the meter provider for metrics.
- **WithNext** (func) - Defines a condition to skip the middleware.
- **WithPort** (int) - Sets the server port attribute.
- **WithPropagators** (propagation.TextMapPropagator) - Sets the propagators for context extraction.
- **WithSpanNameFormatter** (func) - Customizes the span name.
- **WithTracerProvider** (oteltrace.TracerProvider) - Sets the tracer provider.
- **WithoutMetrics** (bool) - Disables metrics collection.
```

--------------------------------

### Define Option interface

Source: https://pkg.go.dev/github.com/gofiber/contrib/otelfiber/v2

Interface for specifying instrumentation configuration options.

```go
type Option interface {
	// contains filtered or unexported methods
}
```

--------------------------------

### Middleware Initialization

Source: https://pkg.go.dev/github.com/gofiber/contrib/otelfiber/v2

The Middleware function returns a fiber.Handler that traces incoming requests. It accepts optional configuration functions to customize the instrumentation behavior.

```APIDOC
## Middleware

### Description
Returns a fiber.Handler that traces incoming requests using OpenTelemetry.

### Method
N/A (Middleware function)

### Parameters
#### Request Body
- **opts** (...Option) - Optional - A variadic list of configuration options to customize tracing and metrics collection.

### Request Example
app.Use(otelfiber.Middleware(otelfiber.WithPort(8080)))
```

--------------------------------

### otelfiber Middleware Signature

Source: https://pkg.go.dev/github.com/gofiber/contrib/otelfiber/v2

The `Middleware` function accepts optional configuration options to customize its behavior.

```go
otelfiber.Middleware(opts ...otelfiber.Option) fiber.Handler
```

--------------------------------

### Define Middleware function

Source: https://pkg.go.dev/github.com/gofiber/contrib/otelfiber/v2

Returns a Fiber handler that traces incoming requests.

```go
func Middleware(opts ...Option) fiber.Handler
```

--------------------------------

### Define HasBasicAuth function

Source: https://pkg.go.dev/github.com/gofiber/contrib/otelfiber/v2

Utility function to check for basic authentication credentials.

```go
func HasBasicAuth(auth string) (string, bool)
```

--------------------------------

### Define otelfiber constants

Source: https://pkg.go.dev/github.com/gofiber/contrib/otelfiber/v2

Constants representing standard OpenTelemetry metric names and units for HTTP server instrumentation.

```go
const (
	MetricNameHttpServerDuration       = "http.server.duration"
	MetricNameHttpServerRequestSize    = "http.server.request.size"
	MetricNameHttpServerResponseSize   = "http.server.response.size"
	MetricNameHttpServerActiveRequests = "http.server.active_requests"

	// Unit constants for deprecated metric units
	UnitDimensionless = "1"
	UnitBytes         = "By"
	UnitMilliseconds  = "ms"
)
```

--------------------------------

### Generate Span Status from HTTP Status Code and Span Kind

Source: https://pkg.go.dev/github.com/gofiber/contrib/otelfiber/v2/internal

Generates an OpenTelemetry status code and message based on an HTTP status code and span kind. Excludes 4xx codes for SERVER span kinds to set the appropriate status.

```go
func SpanStatusFromHTTPStatusCodeAndSpanKind(code int, spanKind trace.SpanKind) (codes.Code, string)
```

--------------------------------

### func SpanStatusFromHTTPStatusCodeAndSpanKind

Source: https://pkg.go.dev/github.com/gofiber/contrib/otelfiber/v2/internal

Generates an OpenTelemetry span status code and message based on the provided HTTP status code and span kind.

```APIDOC
## func SpanStatusFromHTTPStatusCodeAndSpanKind

### Description
Generates a status code and a message as specified by the OpenTelemetry specification for a span. Exclude 4xx for SERVER to set the appropriate status.

### Parameters
- **code** (int) - Required - The HTTP status code.
- **spanKind** (trace.SpanKind) - Required - The OpenTelemetry span kind.

### Response
- **codes.Code** - The resulting OpenTelemetry status code.
- **string** - The status message.
```
Tokens:
Raw