Introduction

config is a simple golang library and designed to read configurations from JSON, Yaml files, environment variables and command line. config depends on go-yaml to anlayze Yaml file and uses built-in golang library to handle JSON file.

Installation

1. Install Yaml library first:

go get gopkg.in/yaml.v2

2. Install config library:

go get github.com/eschao/config

Usage

1. Defines default values

config library supports defining a default value for structure members by using default keyword in structure tags

  type Log struct {
    Path  string `default:"/var/logs"`
    Level string `default:"debug"`
  }

After that, calls config.ParseDefault(interface{}) to set it on structure instance, example codes as the below:

  logConfig := Log{}
  config.ParseDefault(&logConfig)

2. Reads configurations from JSON file

Like analyzing JSON object from file, reading configurations from JSON file is also simple:

  type Database struct {
    Host string     `json:"host"`
    Port int        `json:"port"`
    Username string `json:"username" default:"admin"`
    Password string `json:"password" default:"admin"`
    Log Log         `json:"log"`
  }

Parsing configurations from JSON:

  dbConfig := Database{}
  config.ParseConfigFile(&dbConfig, "config.json")