redis-resp-handler

redis-resp-handler is a fast and lightweight utility for parsing and serializing RESP (Redis Serialization Protocol) messages in Node.js. It supports a variety of data types including arrays, strings, integers, null values, and error messages, making it ideal for handling Redis communication.

Features

• Fast RESP serialization and deserialization: Efficiently parse and serialize RESP messages.
• Support for multiple data types: Handles strings, integers, arrays, error messages, null values, and more.
• Error handling: Throws helpful errors when parsing malformed RESP messages.
• Lightweight and optimized for performance.

Installation

npm install redis-resp-handler

yarn add redis-resp-handler

Usage

Serializing RESP messages

To serialize a RESP message, simply call the serializeToRESP function and pass in the data (data types: null, boolean, number, string, array, or object) you want to serialize.

import { serializeToRESP } from "redis-resp-handler";

const message = serializeToRESP("Hello, Redis!");
console.log(message);  // Outputs: $12\r\nHello, Redis!\r\n

Parsing RESP Messages

To parse a RESP message, use the parseRESPMessage function and pass in the string representation of the message. It will return an array of the parsed elements.

import { parseRESPMessage } from "redis-resp-handler";

const data = "*2\r\n$3\r\nfoo\r\n$3\r\nbar\r\n";
const result = parseRESPMessage(data);
console.log(result);  // Outputs: [ ['foo', 'bar'] ]

API Reference

1. serializeToRESP(data: any): string: Serializes a JavaScript object into a RESP message string.

• Parameters:
  • data (any): The data to serialize (supports strings, numbers, arrays, objects, booleans, null).
• Returns:
  • A RESP formatted string.
• Throws:
  • Error if the data type is unsupported.

2. parseRESPMessage(data: string): any[]: Parses a RESP message string into JavaScript objects.

• Parameters:
  • data (string): The RESP message to parse.
• Returns:
  • An array representing the parsed RESP message.
• Throws:
  • Error if the RESP message is malformed.

Other Utility Methods

1. nullToRESP(): string: Converts null to the RESP format.

• Returns:
  • A RESP string representing null (e.g., _\r\n).

2. booleanToRESP(bool: boolean): string: Converts a boolean value to the RESP format.

• Parameters:
  • bool (boolean): The boolean value to serialize.
• Returns:
  • A RESP string representing the boolean value (e.g., #t\r\n for true or #f\r\n for false).

3. numberToRESP(num: number): string: Converts a number to the RESP format. Handles integers, floating-point numbers, and special cases like Infinity and NaN.

• Parameters:
  • num (number): The number to serialize.
• Returns:
  • A RESP string representing the number. For example:
    • Integer: :42\r\n
    • Floating-point: ,3.14\r\n
    • Infinity: ,inf\r\n
    • NaN: ,nan\r\n
• Throws:
  • Error if the number is too large or small for safe integer serialization.

4. stringToRESP(str: string, type: "bulk" | "simple" = "bulk"): string: Converts a string to the RESP format.

• Parameters:
  • str (string): The string to serialize.
  • type (string, optional): The type of string, either "bulk" (default) or "simple".
• Returns:
  • A RESP string representing the input string. For example:
    • Bulk string: $11\r\nHello, Redis!\r\n
    • Simple string: +OK\r\n
• Throws:
  • Error if an unsupported string type is provided.

5. arrayToRESP(arr: Array<any>): string: Converts an array to the RESP format. Recursively serializes all elements of the array.

• Parameters:
  • arr (Array): The array to serialize.
• Returns:
  • A RESP string representing the array. For example:
    • Array: 2\r\n$3\r\nfoo\r\n$3\r\nbar\r\n

6. objectToRESP(obj: Record<string, any>): string: Converts an object (key-value pairs) to the RESP format. The keys are serialized as strings, and the values are recursively serialized.

• Parameters:
  • obj (Record<string, any>): The object to serialize.
• Returns:
  • A RESP string representing the object as a RESP map. For example:
    • Object: %2\r\n$3\r\nfoo\r\n$3\r\nbar\r\n$3\r\nbaz\r\n:42\r\n

Supported Data Types

• Strings: Simple and bulk strings.
• Integers: Serialized as RESP integers.
• Arrays: Nested arrays are supported.
• Errors: Parsed as JavaScript Error objects.
• Null values: Represented as null.
• Booleans: Serialized as RESP booleans.
• Numbers: Serialized as RESP floating-point numbers.
• Objects: Serialized as RESP bulk strings.
• Complex data structures: Supports nested arrays, objects, and mixed data types.

Unit Tests

A full-fledged unit test suite is available for both serializeToRESP and parseRESPMessage functions, covering all test cases and edge cases. You can visit the repository and run yarn test to execute the tests or modify and add more test cases to ensure reliability and robustness.

License

This package is licensed under the MIT License.

Contributing

Contributions are welcome! Please open an issue or submit a pull request.