peridot/vendor/go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp/config.go
2024-10-16 12:56:53 +02:00

197 lines
5.8 KiB
Go

// Copyright The OpenTelemetry Authors
// SPDX-License-Identifier: Apache-2.0
package otelhttp // import "go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
import (
"context"
"net/http"
"net/http/httptrace"
"go.opentelemetry.io/otel"
"go.opentelemetry.io/otel/metric"
"go.opentelemetry.io/otel/propagation"
"go.opentelemetry.io/otel/trace"
)
// ScopeName is the instrumentation scope name.
const ScopeName = "go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp"
// config represents the configuration options available for the http.Handler
// and http.Transport types.
type config struct {
ServerName string
Tracer trace.Tracer
Meter metric.Meter
Propagators propagation.TextMapPropagator
SpanStartOptions []trace.SpanStartOption
PublicEndpoint bool
PublicEndpointFn func(*http.Request) bool
ReadEvent bool
WriteEvent bool
Filters []Filter
SpanNameFormatter func(string, *http.Request) string
ClientTrace func(context.Context) *httptrace.ClientTrace
TracerProvider trace.TracerProvider
MeterProvider metric.MeterProvider
}
// Option interface used for setting optional config properties.
type Option interface {
apply(*config)
}
type optionFunc func(*config)
func (o optionFunc) apply(c *config) {
o(c)
}
// newConfig creates a new config struct and applies opts to it.
func newConfig(opts ...Option) *config {
c := &config{
Propagators: otel.GetTextMapPropagator(),
MeterProvider: otel.GetMeterProvider(),
}
for _, opt := range opts {
opt.apply(c)
}
// Tracer is only initialized if manually specified. Otherwise, can be passed with the tracing context.
if c.TracerProvider != nil {
c.Tracer = newTracer(c.TracerProvider)
}
c.Meter = c.MeterProvider.Meter(
ScopeName,
metric.WithInstrumentationVersion(Version()),
)
return c
}
// WithTracerProvider specifies a tracer provider to use for creating a tracer.
// If none is specified, the global provider is used.
func WithTracerProvider(provider trace.TracerProvider) Option {
return optionFunc(func(cfg *config) {
if provider != nil {
cfg.TracerProvider = provider
}
})
}
// WithMeterProvider specifies a meter provider to use for creating a meter.
// If none is specified, the global provider is used.
func WithMeterProvider(provider metric.MeterProvider) Option {
return optionFunc(func(cfg *config) {
if provider != nil {
cfg.MeterProvider = provider
}
})
}
// WithPublicEndpoint configures the Handler to link the span with an incoming
// span context. If this option is not provided, then the association is a child
// association instead of a link.
func WithPublicEndpoint() Option {
return optionFunc(func(c *config) {
c.PublicEndpoint = true
})
}
// WithPublicEndpointFn runs with every request, and allows conditionally
// configuring the Handler to link the span with an incoming span context. If
// this option is not provided or returns false, then the association is a
// child association instead of a link.
// Note: WithPublicEndpoint takes precedence over WithPublicEndpointFn.
func WithPublicEndpointFn(fn func(*http.Request) bool) Option {
return optionFunc(func(c *config) {
c.PublicEndpointFn = fn
})
}
// WithPropagators configures specific propagators. If this
// option isn't specified, then the global TextMapPropagator is used.
func WithPropagators(ps propagation.TextMapPropagator) Option {
return optionFunc(func(c *config) {
if ps != nil {
c.Propagators = ps
}
})
}
// WithSpanOptions configures an additional set of
// trace.SpanOptions, which are applied to each new span.
func WithSpanOptions(opts ...trace.SpanStartOption) Option {
return optionFunc(func(c *config) {
c.SpanStartOptions = append(c.SpanStartOptions, opts...)
})
}
// WithFilter adds a filter to the list of filters used by the handler.
// If any filter indicates to exclude a request then the request will not be
// traced. All filters must allow a request to be traced for a Span to be created.
// If no filters are provided then all requests are traced.
// Filters will be invoked for each processed request, it is advised to make them
// simple and fast.
func WithFilter(f Filter) Option {
return optionFunc(func(c *config) {
c.Filters = append(c.Filters, f)
})
}
type event int
// Different types of events that can be recorded, see WithMessageEvents.
const (
ReadEvents event = iota
WriteEvents
)
// WithMessageEvents configures the Handler to record the specified events
// (span.AddEvent) on spans. By default only summary attributes are added at the
// end of the request.
//
// Valid events are:
// - ReadEvents: Record the number of bytes read after every http.Request.Body.Read
// using the ReadBytesKey
// - WriteEvents: Record the number of bytes written after every http.ResponeWriter.Write
// using the WriteBytesKey
func WithMessageEvents(events ...event) Option {
return optionFunc(func(c *config) {
for _, e := range events {
switch e {
case ReadEvents:
c.ReadEvent = true
case WriteEvents:
c.WriteEvent = true
}
}
})
}
// WithSpanNameFormatter takes a function that will be called on every
// request and the returned string will become the Span Name.
func WithSpanNameFormatter(f func(operation string, r *http.Request) string) Option {
return optionFunc(func(c *config) {
c.SpanNameFormatter = f
})
}
// WithClientTrace takes a function that returns client trace instance that will be
// applied to the requests sent through the otelhttp Transport.
func WithClientTrace(f func(context.Context) *httptrace.ClientTrace) Option {
return optionFunc(func(c *config) {
c.ClientTrace = f
})
}
// WithServerName returns an Option that sets the name of the (virtual) server
// handling requests.
func WithServerName(server string) Option {
return optionFunc(func(c *config) {
c.ServerName = server
})
}