Fluentbit exporter

This repo contains the fluentbit exporter for opentelemetry. It allows users to export the telemetry data collected by the various SDK's using a fluentbit/fluentd instance, using the fluentforward protocol.

Provided that you have a fluent instance running on the node, you can export spans to the collector (with the fluentforwardreceiver enabed) or any other fluent instance that is listening using the fluentforward protocol by installing this exporter in your application by simply using the InstallNewPipeline() method as shown:

hostport := "localhost:24224"
serviveName := "fluentforward"
retryTimeout := 10*time.Second
err := fluentforward.InstallNewPipeline(hostport, serviceName, retryTimeout)

While initializing the exporter, we can specify the timeout parameter, which will reconnect to the remote instance every timeout duration, which decreases the chances of writes failing due to connection issues.

If a write fails, the exporter will attempt to reconnect to the fluent instance and will retry the write again before returning.

The data mapping can be found below:

For a span:

Otel-go representation	Otel type	Fluentbit representation	Fluentbit type
TraceID	trace.ID	TraceID	string
SpanID	trace.SpanID	SpanID	string
ParentSpanID	trace.SpanID	ParentSpanID	string
Name	string	Name	string
SpanKind	trace.SpanKind	SpanKind	int
StartTime	time.Time	StartTime	int64
EndTime	time.Time	EndTime	int64
Attributes	[]label.KeyValue	Attrs	map[label.Key]interface{}
DroppedAttributesCount	int	DroppedAttributeCount	int
MessageEvents	trace.Event	MessageEvents	[]event
DroppedEventsCount	int	DroppedEventsCount	int
Links	[]trace.Link	Links	[]link
DroppedLinksCount	int	DroppedLinksCount	int
StatusCode	codes.Code	StatusCode	string
StatusMessage	string	StatusMessage	string
Resource	*resource.Resource	Resource	string
InstrumentationLibrary	Instrumentation.Library	InstrumentationLibraryName, Version	string

Note: The field TraceState is missing in the go implementation

The mappings for an event and a link are as shown:

Link

Otel-go representation	Otel type	Fluentbit representation	Fluentbit type
TraceID	trace.ID	TraceID	string
SpanID	trace.SpanID	SpanID	string
Attributes	[]label.KeyValue	Attrs	map[label.Key]interface{}

Event

Otel-go representation	Otel type	Fluentbit representation	Fluentbit type
Name	string	Name	string
Time	time.Time	Time	int64
Attributes	[]label.KeyValue	Attrs	map[label.Key]interface{}