Jaycue NPM | npm.io

jaycue is my little side project that mimics the best parts jq in pure JavaScript. I wrote a blog post about it on dev.to

I am TDD'ing this to get some practice, using the jq documentation, and hopefully make something useful. Please see below for some similar, more mature, great projects built around jq.

Install

$ npm install jaycue

Usage

const jq = require('jaycue');

console.log(jq({foo: 123}, '.foo'));
123

Supported Filters

Basic Filters

{
  "value": 42,
  "text": "less interesting data",
  "name": {
    "first": "Brian"
    "last": "Olore"
  }
}

filter	output
`.`	`{ "value": 42, "text": "less interesting data","name": { "first": "Brian" "last": "Olore" } }` (object)
`.value`	`42` (number)
`.text`	`less interesting data` (string)
`.["text"]`	`less interesting data` (string)
`.name`	`"name": { "first": "Brian" "last": "Olore" }` (object)
`.name.first`	`Brian` (string)
`.missing`	`undefined`
`.missing?`	`null`
`.["missing"]?`	`null`

Array Filters

["a","b","c","d","e"];

filter	output
`.[]`	`"a","b","c","d","e"` (not json)
`.[0]`	`a`
`.[-2]`	`d`

Array Slicing Filters

filter	output
`.[2:4]`	`["c", "d"]`
`.[:3]`	`["a", "b", "c"]`
`.[:-3]`	`["a", "b"]`
`.[-2:]`	`["d", "e"]`
`.[2:]`	`["c", "d", "e"]`

Select Function

[
  {"id": "first", "val": 1},
  {"id": "second", "val": 2}
]

filter	output
`.[] \\| select(.id == "second")`	`{"id": "second", "val": 2}`
`.[] \\| select(.id == "second") \\| .val`	`2` (number)
`.[] \\| select(.id == "second") .val`	`2` (number)
`.[] \\| select(.id != "second") .val`	`1` (number)