Go OpenTelemetry example

Go OpenTelemetry example.

App Description

Simple app: Orders and Payments services + API GW.

• API GW handles REST requests and proxies them to services
• Orders - create and process orders
• Payments - process payment and return payment info
• Orders handles REST requests from API GW
• Payments handles gRPC requests from API GW
• Payments handles Kafka events from API GW
• Orders saves data to MongoDB
• Payments saves data to PostgreSQL

OpenTelemetry Features

Application contains OpenTelemetry setup:

• Tracer setup with Jaeger exporter
  • Tracer creates spans for all transports: REST, gRPC, Events, DB requests
• Meter setup with Prometheus exporter
• Jaeger and Prometheus deployed with docker-compose

Structure

• /api - contains Kafka, REST and gRPC service and message definitions
• /cmd - application setup
• /config - .env file with environment variables
• /deploy
  • docker-compose.yml - docker-compose file with Jaeger, Prometheus, MongoDB and PostgreSQL setup
• /internal
  • /apigw - API GW service internals
  • /config - config files setup with viper
  • /event - events base controller
  • /grpc - grpc base controller
  • /logger - application logger, creates file transport (for filebeat) and console transport
  • /mongodb - mongodb database setup
  • /order - order service internals
  • /payment - payment service internals
  • /psql - postgres database setup
  • /rest - application REST base controller
  • /telemetry - otel setup files

Local Running

You should deploy dependencies with docker-compose:

cd deploy
docker-compose up -d

Then you could run all services separately:

go run ./cmd/<service-name>/main.go