Go jsconfig

Kailash Nadh, January 2015

MIT License

What?

jsconfig is a tiny JSON configuration file parser for Go with support for comments. Really, JSON spec doesn't include comments, but a configuration file without helpful comments is a pain to deal with.

Moreover, JSON for configuration files is powerful when combined with structs, enabling effortless loading of complex, nested data structures with Go's native JSON Unmarshaling.

Installation (go 1.1+)

go get github.com/knadh/jsonconfig

Usage

Sample file: config.json

Notice the comments

{
	// url to the site
	"url": "http://google.com",

	"methods": ["GET", "POST"], // supported methods

	"always_load": true,

	// nested structure with different types
	"module": {
		"name": "Welcome",
		"route": "/",
		"port": 8080
	}
}

Loading the configuration

package main

import (
	"github.com/knadh/jsonconfig"
)

func main() {
	// setup the structure
	config := struct {
		Url string `json:"url"`

		Methods []string `json:"methods"`

		AlwaysLoad  bool `json:"always_load"`

		Module struct{
			Name string `json:"name"`
			Route string `json:"route"`
			Port int `json:"port"`
		} `json:"module"`
	}{}

	// parse and load json config
	err := jsonconfig.Load("config.json", &config)

	if err == nil {
		println("The url is", config.Url)
		println("Supported methods are", config.Methods[0], config.Methods[1])
		
		println("The module is", config.Module.Name, "on route", config.Module.Route)
	}
}