json-collection

This library provides a simplified simulation of MongoDB's aggregation and query framework in TypeScript. It enables filtering, grouping, sorting, and limiting of in-memory data collections, mimicking the behavior of MongoDB database operations but in a lightweight, local context.

Installation

To use the Json Collection library in your project, install it via npm. Execute the following command in your project directory:

npm install @iyulab/json-collection

Make sure you have Node.js and npm installed on your system. You can download and install Node.js (npm included) from https://nodejs.org/.

Features

The Json Collecgtion library provides the following features:

• Filtering ($match): Filter your data based on specified criteria.
• Grouping and Aggregation ($group): Group your data by specific fields and perform various aggregation operations like counting, summing, averaging, etc.
• Sorting ($sort): Sort your data based on one or more fields.
• Limiting ($limit): Limit the number of documents to return.
• Finding ($find): Retrieve documents from your data based on filtering, sorting, and limiting criteria, simulating the MongoDB find operation.

Usage

Below is a simple example demonstrating how to use the Json Collection library to perform data operations:

import {
  JsonCollection,
  AggregationOptions,
  FindOptions,
} from "@iyulab/json-collection";

// Sample data
const data = [
  { id: 1, name: "Alice", age: 30 },
  { id: 2, name: "Bob", age: 25 },
  { id: 3, name: "Charlie", age: 35 },
  { id: 4, name: "David", age: 40 },
];

// Aggregation example
const aggOptions: AggregationOptions = {
  $match: { age: { $gt: 30 } }, // Filtering: age greater than 30
  $group: { _id: "$age" }, // Grouping by age
  $sort: { age: 1 }, // Sorting by age in ascending order
  $limit: 2, // Limiting to 2 documents
};

const collection = new JsonCollection(data);
const aggResult = collection.aggregate(aggOptions);
console.log(aggResult);

// Find example
const findOptions: FindOptions = {
  $match: { name: { $eq: "Alice" } }, // Filtering: name equals Alice
  $sort: { age: -1 }, // Sorting by age in descending order
  $limit: 1, // Limiting to 1 document
};

const findResult = collection.find(findOptions).toArray();
console.log(findResult);

This will output the processed data based on the provided aggregation options.

• See Find Tests
• See Aggregate Tests

Contribution

Contributions are welcome! Please feel free to submit pull requests or open issues to improve the library or add new features.

License

This project is licensed under the MIT License - see the LICENSE.md file for details.