ReadEOF

A high-performance, memory-efficient library to read large files backward (line-by-line). Zero dependencies.

Features

Fast file reading from the end without loading entire file into memory
Memory efficient using configurable buffer sizes
Supports various encodings

Installation

npm install readeof

Usage

Basic Example

import { readeof } from 'readeof';

// Read last 10 lines from log file
const lastLines = await readeof('/var/log/app.log', 10);
console.log(lastLines);

Reading Recent Logs

import { readeof } from 'readeof';

// Read last 50 lines for debugging
const recentLogs = await readeof('./app.log', 50);
console.log(recentLogs);

Custom Encoding

import { readeof } from 'readeof';

// Read file with latin1 encoding
const content = await readeof('./data.txt', 20, 'latin1');

Custom Buffer Size

import { readeof } from 'readeof';

// Use 64KB buffer for very large files
const content = await readeof('./huge-log.log', 100, 'utf8', 64 * 1024);

Real-time Log Monitoring

import { readeof } from 'readeof';

async function monitorLog(filePath: string) {
  setInterval(async () => {
    const latestLines = await readeof(filePath, 5);
    console.clear();
    console.log('=== Latest Logs ===');
    console.log(latestLines);
  }, 2000);
}

monitorLog('/var/log/application.log');

Error Analysis

import { readeof } from 'readeof';

async function findRecentErrors(logPath: string) {
  const recentLogs = await readeof(logPath, 1000);
  const errors = recentLogs
    .split('\n')
    .filter(line => line.includes('ERROR'));
  
  console.log(`Found ${errors.length} errors in last 1000 lines`);
}

License

See LICENSE file for details.

Author

Ashary Vermaysha (vermaysha@gmail.com)