jso\nl

> Transform a stream of JSON into a stream of Line Delimited JSON

Install

``sh
$ npm install --save jsonl
`

Use

$3

`js
var fs = require("fs")
var jsonl = require("jsonl")

fs.createReadStream("./in.json")
.pipe(jsonl())
.pipe(fs.createWriteStream("./out.json"))
`
#### in.json
`json
[{"test":"value"},{"test":"value"},{"test":"value"},{"test":"value"}]
`
#### out.json
`json
{"test":"value"}
{"test":"value"}
{"test":"value"}
{"test":"value"}

`

$3


`js
var fs = require("fs")
var jsonl = require("jsonl")
var through = require("through2")
var stream = through.obj()

stream.pipe(jsonl({toBufferStream:true}))
.pipe(fs.createWriteStream("./out.json"))

stream.push({test:"value"})
stream.push({test:"value"})
stream.push({test:"value"})
stream.push({test:"value"})
stream.end()
`
#### out.json
`json
{"test":"value"}
{"test":"value"}
{"test":"value"}
{"test":"value"}

`

$3


To get the results you expect, you will likely need to know the structure of your incoming data. You may have to pass a depth property, which corresponds to the layer of the property in a serialized, nested JSON object.

By default, jsonl will use a depth of 1 when reading data from a Buffer stream (expecting objects to be nested in an array), and a depth of 0 from a stream in object mode.

`js
/0/[
/1/ {
/2/ test: "value"
/1/ },
/1/ {
/2/ test: "value"
/1/ }
/0/]
`

$3

To filter the incoming data based on properties, you can select specific fields to be plucked out of the incoming object.

\* You will need to specify a depth property for the nested level of the property.


`js
var fs = require("fs")
var jsonl = require("jsonl")

fs.createReadStream("./in.json")
.pipe(jsonl({pluck:["category"], depth:2}))
.pipe(fs.createWriteStream("./out.json"))
`
#### in.json
`json
[{"category": "cactus heights", "question":"?", "answer": "!"},{"category": "giraffe shoe sizes", "question":"?", "answer": "!"}]
`
#### out.json
`json
{"category":"cactus heights"}
{"category":"giraffe shoe sizes"}

`

API

$3

#### opts.depth
- Type: Number (default: 1)

The depth of the objects in the incoming data to pluck out. This is what you want for an array of objects, such as:

`json
[{"this":"that"},{"this":"that"}]
`

#### opts.objectMode
- Type: Boolean (default: false)

Convert data into an object stream.

#### opts.pluck
- Type: Array|String (default: [])

Only return select properties from JSON objects.

#### opts.separator
- Type: String (default: \n)

String to separate object data with.

#### opts.toBufferStream
- Type: Boolean (default: false)

Set this to true when you have an object stream that you would like converted to a stream of line delimited JSON buffers.

If set, this defaults opts.depth to 0`, but can still be overridden.

License

MIT © Stephen Sawchuk