comment

Golang package for use comments in JSON config files

Programming language: Go

License: MIT License

Tags: Utilities     Configuration     Miscellaneous    

README

comment

Golang package for use comments in JSON config files

Motivation

json config file: config.json

{
  "name": "example",
  "address": "192.168.0.1",
  "active": true
}

How we can change address?

Create a new file config2.json or fix in the current one.

Both variants are not convenient.

What is proposed

Introduce end-line comment. For shielding use the symbol #.

new json-config file with comments config.cjson

{
  "name": "example",
  # "address": "192.168.0.1", - this line is commented
  "address": "192.168.0.2", # New address!
  "active": true 
}

Easier and convenient than previous both variants.

For parse this file first use the function comment.Trim(data). We obtain the following:

{
  "name": "example",
  "address": "192.168.0.2", 
  "active": true 
}

Next, we use standard parser json.Unmarshal

package main

import (
    "encoding/json"
    "fmt"
    "io/ioutil"
    "log"

    "github.com/toelsiba/comment"
)

type Config struct {
    Name    string `json:"name"`
    Address string `json:"address"`
    Active  bool   `json:"active"`
}

func main() {

    data, err := ioutil.ReadFile("config.cjson")
    if err != nil {
        log.Fatal(err)
    }

    data = comment.Trim(data)
    fmt.Println(string(data))

    var config Config
    err = json.Unmarshal(data, &config)
    if err != nil {
        log.Fatal(err)
    }

    fmt.Printf("%+v\n", config)
}

Or more short variant:

func main() {
    var c Config
    err := comment.ReadConfig("config.cjson", &c)
    if err != nil {
        log.Fatal(err)
    }
    fmt.Println(c)
}

If you need have symbol # in line - used doublet ##.