go-micro

go-micro

go-micro microservice framework template

This is a small template for creating a new microservice in go.

Its not intended to be a fully featured microservice framework, just a small starting point with the things i normally need to build up a small, fast go microservice.

The project structure depends on this: https://github.com/golang-standards/project-layout

Features:

• usage of Opentracing/jaeger
• gelf logging
• authorization with jwt
• cached healthcheck, livez and readyz endpoints
• https/ssl and http for payload and metrics/healthcheck
• metrics with Prometheus: https://prometheus.io/docs/guides/go-application/
• Docker build with builder and target image
• chi as the router framework
• go 1.21
• automatic config substitution

Why using this and not a framework?

Because you gain more flexibility. See this little repo as a starting point for writing your own microservice framework for you or your company.

Configuration

In this template the configuration will be automatically loaded. You have the following options to set the service configuration file.

• default: the service will try to load the configuration from the <userhome>/<servicename>/service.yaml
• via Commandline: -c <configfile> will load the configuration from this file

IN the configuration file you can use ${} macros for adding environment variables for the configuration itself. This will not work on the secret.yaml. The secret.yaml (if given in the configuration) will load a partial configuration from another file. (Mainly for separating credentials from the other configuration) Be aware, you manually have to merge both configuration in the config.mergeSecret() function.

Secrets

Die Konfiguration kann in 2 Teile aufgespalten werden. Einmal in die normale Konfiguration. Zusätzlich können bestimmte Teile z.B. Credentials in eine 2.Datei ausgelagert werden. Diese können dann über einen anderen Mechanismus (z.B. per Kubernetes secret store) zur Verfügung gestellt werden. Die Struktur muss identisch sein. Diese 2. Datei wird dann über den Eintrag secretfile in der config.yaml referenziert. Beim Servicestart werden alle Werte über die Werte der config.yaml geladen.

secretfile: "./config/secret.yaml"

Enviroment

Werte der config Dateien können durch Enviroment Variablen ersetzt werden. Dazu werden {$name} im String ersetzt mit den entsprechenden Werten von aktuelle Umgebungsvariablen. Verweise auf undefinierte Variablen werden durch einen leeren String ersetzt.

Prometheus integration

You can switch on the prometheus integration simply by adding

metrics:
  enable: true

to the service config.

How to add a new counter?

Simply on the class, where you want to add a new counter (or something else) make a new variable with:

var (
  postConfigCounter = promauto.NewCounter(prometheus.CounterOpts{
	 Name: "gomicro_post_config_total",
     Help: "The total number of post config requests",
  })
)

In the code where to count the events simply do an

postConfigCounter.Inc()

Thats all. More examples here: https://prometheus.io/docs/guides/go-application/