Task Tracker CLI

This project is a fully completed solution for the Task Tracker Project on Roadmap.sh. A lightweight, high-performance Command Line Interface (CLI) task tracking application built with native Node.js (ES Modules). This tool operates entirely in the terminal, managing a localized persistent database layer with optimized data lookup speeds.

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Architecture & Performance Design

Unlike typical beginner implementations that store collection data sets inside flat JSON arrays—forcing an expensive linear sequential search ($O(N)$) every time a task is read, updated, or modified—this project implements a Hash Map Document Storage Pattern.

• Data Layout: Data is stored on disk inside an associative key-value object bucket (data dictionary mapped by unique task IDs).
• Time Complexity Optimization: By mapping operations through explicit string hashing keys, finding a task or modifying its status operates at an optimal Constant Time Complexity ($O(1)$). Execution runtime remain instant, completely independent of whether the database scales to 10 records or 10 million records.

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Tech Stack & Pillars Covered

• Runtime Environment: Node.js (v24+)
• Module System: ECMAScript Modules (ESM) via "type": "module"
• Persistence Layer: Structured Synchronous File System I/O isolation (node:fs)
• Pillars Mastered: High-Performance Caching Patterns, Defensive Synchronous I/O Boundary Isolation, and Algorithmic Complexity Mapping.

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Project Directory Structure

task-tracker/
├── package.json          
├── package-lock.json
└── src/
    ├── data/
        └── tasks.json
    ├── server.js         
    └── utils/
        └── utility.js    

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Setup and Global Installation

To install this tool and run it natively from anywhere across your machine's filesystem without needing to type node prefixes, execute the following configuration steps:

1. Enable Global Command Line Permissions

Navigate to your project folder and grant your main server router execution permissions within your environment shell:

chmod +x src/server.js

2. Symlink the Binary to Global Env

Instruct your package manager to link the binary tag (task-cli) specified in your package.json to your system path:

npm link

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Command Execution Suite

Now, open a completely separate terminal window, navigate away to any directory, and manage your workflow matrix seamlessly:

1. Initialize & Append Tasks (add)

Adds a task directly into your storage map. The ID increments automatically.

task-cli add "Configure PostgreSQL indices"
task-cli add "Complete Redis University labs"

2. List Your Task Matrix (list)

Converts the internal dictionary to a clean flat array frame on-the-fly for terminal layout rendering.

task-cli list

3. Filter Contexts by Status (list [status])

Isolates tasks matching precise execution lanes: todo, in-progress, or done.

task-cli list todo

4. Direct Constant-Time Status Mutator (update)

Updates a task status instantly in O(1) time by passing the ID and the target status category.

task-cli update 1 in-progress
task-cli update 2 done

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Defensive Code Protections Included

• Self-Healing State Fallbacks: The data parsing controller includes structural bounds that catch empty files (0-bytes) on-the-fly, auto-initializing a clean database layout scheme dynamically to prevent application crashes under Unexpected end of JSON input errors.
• Early-Exit Gate Validation: Inputs are guarded heavily against numeric falsification or empty payload arguments, keeping corrupt writes completely out of the local disk infrastructure.