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Logging From Go

This feature requires AppSignal Collector version 0.7.0 or higher.

This documentation outlines how to configure logging with the AppSignal for Go integration.

Configure Logging

Do not send Personal Identifiable Information (PII) to AppSignal. Filter PII (e.g., names, emails) from logs and use an ID, hash, or pseudonymized identifier instead.

For HIPAA-covered entities, more information about signing a Business Associate Agreement (BAA) can be found in our Business Add-Ons documentation.

You do not need to create a log source to send logs from the AppSignal for Go integration. An "application" log source will be created automatically.

The Go integration uses OpenTelemetry's logging capabilities to send logs to AppSignal.

Stand-alone usage

To use logging with OpenTelemetry in Go, you need to set up the logger using OpenTelemetry's logger provider.

Go
package main
 
import (
	"context"
	"go.opentelemetry.io/otel"
	"go.opentelemetry.io/otel/log"
)
 
func main() {
	// Get the logger from the global logger provider
	loggerProvider := otel.GetLoggerProvider()
	logger := loggerProvider.Logger("my-app")
 
	// Log a message
	logger.Emit(context.Background(), log.Record{
		Severity: log.SeverityInfo,
		Body:     log.StringValue("Log message line"),
	})
}

Usage with slog

This feature requires Go version 1.21 or higher.

You can configure the standard slog package to send structured logs to AppSignal using the OpenTelemetry handler.

Go
package main
 
import (
	"context"
	"log/slog"
	"go.opentelemetry.io/contrib/bridges/otelslog"
)
 
func main() {
	// Create an OpenTelemetry `slog` handler
	otelHandler := otelslog.NewHandler("my-app")
 
	// Create a `slog` logger with the OpenTelemetry handler
	logger := slog.New(otelHandler)
 
	// Use the logger
	logger.Info("Log message line")
	logger.With("user_id", 123).Info("User logged in")
	logger.Error("An error occurred", "error", "database connection failed")
}

Usage

Sending Logs

Using the OpenTelemetry logger directly, you can define the severity level of your logs:

Go
package main
 
import (
	"context"
	"go.opentelemetry.io/otel"
	"go.opentelemetry.io/otel/log"
)
 
func main() {
	loggerProvider := otel.GetLoggerProvider()
	logger := loggerProvider.Logger("my-app")
 
	// Different severity levels
	logger.Emit(context.Background(), log.Record{
		Severity: log.SeverityWarn,
		Body:     log.StringValue("Something went wrong"),
	})
 
	logger.Emit(context.Background(), log.Record{
		Severity: log.SeverityInfo,
		Body:     log.StringValue("Action completed"),
	})
 
	logger.Emit(context.Background(), log.Record{
		Severity: log.SeverityError,
		Body:     log.StringValue("Database connection failed"),
	})
}

You can define custom attributes to send log information that can be used when filtering and querying logs:

Go
package main
 
import (
	"context"
	"go.opentelemetry.io/otel"
	"go.opentelemetry.io/otel/log"
)
 
func processInvoice(customerID string) {
	loggerProvider := otel.GetLoggerProvider()
	logger := loggerProvider.Logger("invoice_helper")
 
	logger.Emit(context.Background(), log.Record{
		Severity: log.SeverityInfo,
		Body:     log.StringValue("Generating invoice for customer"),
		Attributes: []log.KeyValue{
			log.String("customer_id", customerID),
		},
	})
 
	invoice := generateInvoice(customerID)
 
	logger.Emit(context.Background(), log.Record{
		Severity: log.SeverityInfo,
		Body:     log.StringValue("Generated invoice for customer"),
		Attributes: []log.KeyValue{
			log.String("customer_id", customerID),
			log.String("invoice_id", invoice.ID),
		},
	})
}

You can query and filter on message contents and attribute values from within the Log Management tool.

Once configured, the desired attributes will be sent to AppSignal as log tags, and be queryable in the AppSignal logging interface.

Filtering Logs

You can use the ignore_logs configuration option to ignore log lines. See our Ignore Logs guide to learn more.

Need Help?

After configuring your Go application to send logs, logs should appear in AppSignal. If you are unsure about this step or AppSignal is not receiving any logs, you can always reach out for assistance. We'll help get you back on track!