JSONSki

JSONSki_Nodejs is the Node.Js (Javascript) binding port for JSONSki

JSONSki is a streaming JSONPath processor with fast-forward functionality. During the streaming, it can automatically fast-forward over certain JSON substructures that are irrelavent to the query evaluation, without parsing them in detail. To make the fast-forward efficient, JSONSki features a highly bit-parallel solution that intensively utilizes bitwise and SIMD operations that are prevelent on modern CPUs to implement the fast-forward APIs.

NPM Package

You can download the npm package from here - https://www.npmjs.com/package/jsonski

Installation

npm i jsonski

Quick Start

const JSki = require('jsonski')
console.log(JSki.JSONSkiParser("$.features[150].actor.login", "datasets/test.json"));

• We interface the following method:

JSki.JSONSkiParser(args1, args2)    //args1 - String(query) and args2 - String(file_location)

Requirements

Hardware requirements

• CPUs: 64-bit ALU instructions, 256-bit SIMD instruction set, and the carry-less multiplication instruction (pclmulqdq)
• Operating System: Linux, MacOs (Intel Chips only)
• C++ Compiler: g++ (7.4.0 or higher)

Software requirements

Before starting to use Node-API you need to assure you have the following prerequisites:

• Node.JS (v14 and above) see: Installing Node.js

• Python (v3.7 and above) see: Installing Python

• C++ : g++ (v7.4.0 and above) see: Installing C++

Getting Started with Querying using JSONSki

JSONPath

JSONPath is the basic query language of JSON data. It refers to substructures of JSON data in a similar way as XPath queries are used for XML data. For the details of JSONPath syntax, please refer to Stefan Goessner's article.

JSONSki Queries Operators

| Operator | Description | | :-----------------------: |:-----------------:| | $ | root object | | . | child object | | [] | child array | | * | wildcard, all objects or array members | | [index] | array index | | [start:end] | array slice operator |

Path Examples

Consider a piece of geo-referenced tweet in JSON

{
    "coordinates": [
        40.74118764, -73.9998279
    ],
    "user": {
        "id": 6253282
    },
    "place": {
        "name": "Manhattan",
        "bounding_box": {
            "type": "Ploygon",
            "pos": [
                [-74.026675, 40.683935],
                ......
            ]
        }
    }
}

| JsonPath | Result | | :------- | :----- | | $.coordinates[*] | all coordinates | | $.place.name | place name | | $.place.bounding_box.pos[0]| first position of the bounding box in place | | $.place.bounding_box.pos[0:2]| first two positions of the bounding box in place |

Performance Comparison with Javascript Parsing

Below is an example usage of Jsonski npm package.

const JSki = require('jsonski')
const fs = require('fs');
console.time();
console.log('JsonSki Runtime', JSki.JSONSkiParser("$[*].entities.urls[*].url", "dataset/twitter_sample_large_record.json"));
console.timeEnd();

file_contents = fs.readFileSync('dataset/twitter_sample_large_record.json')
str = file_contents.toString()
console.log("Javascript Runtime")
console.time();
var json = JSON.parse(str);
console.timeEnd();

• Note: The code snippet above benchmarks performance for Javascript parsing VS JSONSki_nodejs parsing.

Publication

[1] Lin Jiang and Zhijia Zhao. JSONSki: Streaming Semi-structured Data with Bit-Parallel Fast-Forwarding. In Proceedings of the Twenty-Third International Conference on Architectural Support for Programming Languages and Operating Systems (ASPLOS), 2022.

@inproceedings{jsonski,
  title={JSONSki: Streaming Semi-structured Data with Bit-Parallel Fast-Forwarding},
  author={Lin Jiang and Zhijia Zhao},
  booktitle={Proceedings of the Twenty-Third International Conference on Architectural Support for Programming Languages and Operating Systems (ASPLOS)},
  year={2022}
}

Performance

Benchmarking

Performance of JSONSki_nodejs is compared with simdjson_nodejs and Javascript Parsing - https://github.com/AutomataLab/NPM-JSON-Parser-Benchmarking