Command line JSON parser.

parse_json

#!/usr/bin/env luajit

-- author : Narate Ketram
-- github.com/narate
-- $ echo '{"name":"narate"}' | parse_json name
-- "narate"

local cjson = require 'cjson.safe'
local data = io.read('*all')
local json = cjson.decode(data)

if not json then
    print('Invalid json')
    return
end

local key = tonumber(arg[1]) or arg[1]
if not key then
    print(data)
    return
end
print(cjson.encode(json[key]) or 'not found')

Requirement

• luajit 2.x+
• cjson 2.1.x+ (with cjson.safe support)

Setup

• Download parse_json
• Make parse_json executable ( $ chmod +x parse_json )
• Add parse_json to your $PATH

Example

$ curl -s httpbin.org/headers
{
  "headers": {
    "Accept": "*/*",
    "Host": "httpbin.org",
    "User-Agent": "curl/7.37.1"
  }
}

$ curl -s httpbin.org/headers | parse_json headers
 {"Accept":"*\/*","User-Agent":"curl\/7.37.1","Host":"httpbin.org"}

$ curl -s httpbin.org/headers | parse_json headers | parse_json Host
"httpbin.org"

ผมลง luajit และใช้ luarocks ลง lua-cjson แต่ว่ามันหา cjson ไม่เจอนะครับ ทำยังไงดี