├── LICENSE
├── README.md
└── jsonconfig.go


/LICENSE:
--------------------------------------------------------------------------------
 1 | The MIT License (MIT)
 2 | 
 3 | Copyright (c) 2015 Kailash Nadh
 4 | 
 5 | Permission is hereby granted, free of charge, to any person obtaining a copy of
 6 | this software and associated documentation files (the "Software"), to deal in
 7 | the Software without restriction, including without limitation the rights to
 8 | use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
 9 | the Software, and to permit persons to whom the Software is furnished to do so,
10 | subject to the following conditions:
11 | 
12 | The above copyright notice and this permission notice shall be included in all
13 | copies or substantial portions of the Software.
14 | 
15 | THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 | IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
17 | FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
18 | COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
19 | IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
20 | CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
21 | 


--------------------------------------------------------------------------------
/README.md:
--------------------------------------------------------------------------------
 1 | # Go jsconfig
 2 | 
 3 | Kailash Nadh, January 2015
 4 | 
 5 | MIT License
 6 | 
 7 | ## What?
 8 | 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.
 9 | 
10 | 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.
11 | 
12 | ## Installation (go 1.1+)
13 | `go get github.com/knadh/jsonconfig`
14 | 
15 | ## Usage
16 | ### Sample file: config.json
17 | Notice the comments
18 | <pre>
19 | {
20 | 	// url to the site
21 | 	"url": "http://google.com",
22 | 
23 | 	"methods": ["GET", "POST"], // supported methods
24 | 
25 | 	"always_load": true,
26 | 
27 | 	// nested structure with different types
28 | 	"module": {
29 | 		"name": "Welcome",
30 | 		"route": "/",
31 | 		"port": 8080
32 | 	}
33 | }
34 | </pre>
35 | 
36 | ### Loading the configuration
37 | ```go
38 | package main
39 | 
40 | import (
41 | 	"github.com/knadh/jsonconfig"
42 | )
43 | 
44 | func main() {
45 | 	// setup the structure
46 | 	config := struct {
47 | 		Url string `json:"url"`
48 | 
49 | 		Methods []string `json:"methods"`
50 | 
51 | 		AlwaysLoad  bool `json:"always_load"`
52 | 
53 | 		Module struct{
54 | 			Name string `json:"name"`
55 | 			Route string `json:"route"`
56 | 			Port int `json:"port"`
57 | 		} `json:"module"`
58 | 	}{}
59 | 
60 | 	// parse and load json config
61 | 	err := jsonconfig.Load("config.json", &config)
62 | 
63 | 	if err == nil {
64 | 		println("The url is", config.Url)
65 | 		println("Supported methods are", config.Methods[0], config.Methods[1])
66 | 		
67 | 		println("The module is", config.Module.Name, "on route", config.Module.Route)
68 | 	}
69 | }
70 | ```


--------------------------------------------------------------------------------
/jsonconfig.go:
--------------------------------------------------------------------------------
 1 | // Package jsonconfig is a super tiny (pseudo) JSON configuration parser for Go with support for comments.
 2 | 
 3 | // Kailash Nadh, http://nadh.in/code/jsonconfig
 4 | // Jan 2015
 5 | // MIT License
 6 | 
 7 | package jsonconfig
 8 | 
 9 | import (
10 | 	"encoding/json"
11 | 	"errors"
12 | 	"io/ioutil"
13 | 	"regexp"
14 | )
15 | 
16 | func Load(filename string, config interface{}) error {
17 | 	// Read the config file.
18 | 	data, err := ioutil.ReadFile(filename)
19 | 	if err != nil {
20 | 		return errors.New("Error reading file")
21 | 	}
22 | 
23 | 	// Regex monstrosity because of the lack of lookbehinds/aheads.
24 | 
25 | 	// Standalone comments.
26 | 	r1, _ := regexp.Compile(`(?m)^(\s+)?//(.*)$`)
27 | 
28 | 	// Numbers and boolean.
29 | 	r2, _ := regexp.Compile(`(?m)"(.+?)":(\s+)?([0-9\.\-]+|true|false|null)(\s+)?,(\s+)?//(.*)$`)
30 | 
31 | 	// Strings.
32 | 	r3, _ := regexp.Compile(`(?m)"(.+?)":(\s+)?"(.+?)"(\s+)?,(\s+)?//(.*)$`)
33 | 
34 | 	// Arrays and objects.
35 | 	r4, _ := regexp.Compile(`(?m)"(.+?)":(\s+)?([\{\[])(.+?)([\}\]])(\s+)?,(\s+)?//(.*)$`)
36 | 
37 | 	res := r1.ReplaceAllString(string(data), "")
38 | 	res = r2.ReplaceAllString(res, `"$1": $3,`)
39 | 	res = r3.ReplaceAllString(res, `"$1": "$3",`)
40 | 	res = r4.ReplaceAllString(res, `"$1": $3$4$5,`)
41 | 
42 | 	// Decode json.
43 | 	if err := json.Unmarshal([]byte(res), &config); err != nil {
44 | 		return err
45 | 	}
46 | 
47 | 	return nil
48 | }
49 | 


--------------------------------------------------------------------------------