observer/pkg/exporters/exporters.go

package exporters

import (
	"context"
	"git.ma-al.com/gora_filip/pkg/exporters/console_exporter"
	gelf_exporter "git.ma-al.com/gora_filip/pkg/exporters/gelf_exporter"
	otlphttp_exporter "go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp"
	sdktrace "go.opentelemetry.io/otel/sdk/trace"
)

// Private type preventing implementation of TraceProcessor by external packages.
type traceProviderOpt sdktrace.TracerProviderOption

type TraceExporter interface {
	IntoTraceProviderOption() traceProviderOpt
}

func NewFromSpanExporter(exporter sdktrace.SpanExporter) ExporterWithConfig {
	return ExporterWithConfig{
		exporter: exporter,
	}
}

// Sneaky wrapper that makes it so that the TraceExporter can be created from SpanProcessor.
type proc struct {
	sdktrace.SpanProcessor
}

func (p proc) IntoTraceProviderOption() traceProviderOpt {
	return sdktrace.WithSpanProcessor(p)
}

func NewFromSpanProcessor(processor sdktrace.SpanProcessor) TraceExporter {
	return TraceExporter(proc{
		SpanProcessor: processor,
	})
}

// Combined exporter with batch processor config
type ExporterWithConfig struct {
	exporter sdktrace.SpanExporter
	config   []sdktrace.BatchSpanProcessorOption
}

func (ecfg ExporterWithConfig) Add(opt sdktrace.BatchSpanProcessorOption) ExporterWithConfig {
	ecfg.config = append(ecfg.config, opt)
	return ecfg
}

func (ecfg ExporterWithConfig) IntoTraceProviderOption() traceProviderOpt {
	return sdktrace.WithBatcher(ecfg.exporter, ecfg.config...)
}

// An exporter printing to console with very small delay
func DevConsoleExporter(opts ...console_exporter.ProcessorOptions) TraceExporter {
	var exporter TraceExporter
	if len(opts) > 0 {
		exporter = NewFromSpanProcessor(console_exporter.NewProcessor(opts[0]))
	} else {
		exporter = NewFromSpanProcessor(console_exporter.DefaultConsoleExportProcessor())
	}
	return TraceExporter(exporter)
}

// Default exporter to Graylog.
func GelfExporter(opts ...gelf_exporter.Option) (ExporterWithConfig, error) {
	gelfExp, err := gelf_exporter.New(opts...)
	return NewFromSpanExporter(gelfExp), err
}

// Exporter for traces over HTTP. Can be used with Jaeger.
// See documentation of [otlhttp_exporter] for details.
func OtlpHTTPExporter(opts ...otlphttp_exporter.Option) (ExporterWithConfig, error) {
	otlpExp, err := otlphttp_exporter.New(context.Background(), opts...)
	return NewFromSpanExporter(otlpExp), err
}