propagation

type Config struct {
	// contains filtered or unexported fields
}

type HTTPExtractor interface {
	// Extract method retrieves encoded information using supplier
	// from the associated carrier, decodes it and creates a new
	// context containing the decoded information.
	//
	// Information can be a correlation context or a remote span
	// context. In case of span context, the propagator should
	// store it in the context using
	// trace.ContextWithRemoteSpanContext. In case of correlation
	// context, the propagator should use correlation.WithMap to
	// store it in the context.
	Extract(ctx context.Context, supplier HTTPSupplier) context.Context
}

type HTTPInjector interface {
	// Inject method retrieves information from the context,
	// encodes it into propagator specific format and then injects
	// the encoded information using supplier into an associated
	// carrier.
	Inject(ctx context.Context, supplier HTTPSupplier)
}

type HTTPPropagator interface {
	HTTPInjector
	HTTPExtractor

	// GetAllKeys returns the HTTP header names used.
	GetAllKeys() []string
}

type HTTPSupplier interface {
	// Get method retrieves a single value for a given key.
	Get(key string) string
	// Set method stores a single value for a given key. Note that
	// this should not be appending a value to some array, but
	// rather overwrite the old value.
	Set(key string, value string)
}

type Option func(*Config)

type Propagators interface {
	// HTTPExtractors returns the configured extractors.
	HTTPExtractors() []HTTPExtractor

	// HTTPInjectors returns the configured injectors.
	HTTPInjectors() []HTTPInjector
}