wasilak/otelgo

package logs

import (
    "context"
    "os"

    "dario.cat/mergo"
    "go.opentelemetry.io/otel/attribute"
    "go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploggrpc"
    "go.opentelemetry.io/otel/exporters/otlp/otlplog/otlploghttp"
    "go.opentelemetry.io/otel/log/global"
    sdk "go.opentelemetry.io/otel/sdk/log"
    "go.opentelemetry.io/otel/sdk/resource"
    semconv "go.opentelemetry.io/otel/semconv/v1.25.0"
)

type OtelGoLogsConfig struct {
    Attributes []attribute.KeyValue `json:"attributes"` // Attributes specifies the attributes to be added to the logger resource. Default is an empty slice.
}

var defaultConfig = OtelGoLogsConfig{
    Attributes: []attribute.KeyValue{
        semconv.ServiceNameKey.String(os.Getenv("OTEL_SERVICE_NAME")),
        semconv.ServiceVersionKey.String("v0.0.0"),
    },
}

func Init(ctx context.Context, config OtelGoLogsConfig) (context.Context, *sdk.LoggerProvider, error) {
    err := mergo.Merge(&defaultConfig, config, mergo.WithOverride)
    if err != nil {
        return ctx, nil, err
    }

    res, err := resource.New(ctx,
        resource.WithHost(),
        resource.WithContainer(),
        resource.WithProcess(),
        resource.WithTelemetrySDK(),
        resource.WithOS(),
        resource.WithFromEnv(),
        resource.WithAttributes(defaultConfig.Attributes...),
    )
    if err != nil {
        return ctx, nil, err
    }

    var exporter sdk.Exporter

    if os.Getenv("OTEL_EXPORTER_OTLP_PROTOCOL") == "grpc" {
        exporter, err = otlploggrpc.New(ctx)
        if err != nil {
            return ctx, nil, err
        }
    } else {
        exporter, err = otlploghttp.New(ctx)
        if err != nil {
            return ctx, nil, err
        }
    }

    processor := sdk.NewBatchProcessor(exporter)

    logProvider := sdk.NewLoggerProvider(
        sdk.WithResource(res),
        sdk.WithProcessor(processor),
    )

    // Handle shutdown properly so nothing leaks.
    // defer func() {
    //     if err := logProvider.Shutdown(ctx); err != nil {
    //         log.Fatalln(err)
    //     }
    // }()

    global.SetLoggerProvider(logProvider)

    return ctx, logProvider, nil
}