ReadStreamLineByLine

is a NodeJS module that helps you reading large text files, line by line using stream, without buffering the files into memory.

Installation:

npm install readstreamlinebyline

Usage:

Asynchronous processing of lines:

    const ReadLine = require('readstreamlinebyline');
    const prodctModel = require("../Model/ProductModel");

    module.exports = async function (req, res) {
        var readLine = ReadLine('D:\Chinmoy\Document\data.txt'),arr=[];
        readLine.on("start", async function (result, doneFlag) {
            arr.push(JSON.parse(result));
            if(arr.length == 1000){
                console.log("insert 1000 recodrs");
                await prodctModel.insertMany(arr);
                arr.length = 0;
            }
            doneFlag();
        })
        readLine.on("done", function(){
            res.status(200).send("Done");
        })
    }

Initialize with Stream:

const ReadLine = require('readstreamlinebyline');
var rl = ReadLine('D:\Chinmoy\Document\data.txt'),arr=[];

API:

Class: ReadLine(path)

path specifies the file to read or Stream

Event: 'start'

function (result, done) { }

Emitted on every line read.

result contains the each line.

done contains the method which should call after every line read. It is like the done method of promise. By using this method we can call Asynchronous task for every line for a large file.

Event: 'done'

function (error) { }

Emitted when read operation of every line will compelete.

License:

The MIT License (MIT)

Package detail