redis-errors

What is redis-errors?

The redis-errors npm package provides a set of custom error classes for handling Redis-related errors in a more structured and meaningful way. It helps developers to catch and handle specific Redis errors more effectively.

What are redis-errors's main functionalities?

Custom Error Classes

The package provides custom error classes like ReplyError, AbortError, ParserError, and AggregateError. These classes help in identifying and handling specific types of Redis errors.

const { ReplyError, AbortError, ParserError, AggregateError } = require('redis-errors');

try {
  // Simulate a Redis operation that throws an error
  throw new ReplyError('This is a reply error');
} catch (error) {
  if (error instanceof ReplyError) {
    console.error('Caught a ReplyError:', error.message);
  }
}

Error Handling

The package allows for structured error handling by checking the instance of the error and responding accordingly. This makes it easier to debug and manage Redis-related errors.

const { ReplyError, AbortError, ParserError, AggregateError } = require('redis-errors');

function handleError(error) {
  if (error instanceof ReplyError) {
    console.error('ReplyError:', error.message);
  } else if (error instanceof AbortError) {
    console.error('AbortError:', error.message);
  } else if (error instanceof ParserError) {
    console.error('ParserError:', error.message);
  } else if (error instanceof AggregateError) {
    console.error('AggregateError:', error.message);
  } else {
    console.error('Unknown error:', error.message);
  }
}

try {
  // Simulate a Redis operation that throws an error
  throw new AbortError('This is an abort error');
} catch (error) {
  handleError(error);
}

Other packages similar to redis-errors

ioredis

ioredis is a robust, full-featured Redis client for Node.js. It provides built-in error handling for various Redis errors, but it does not offer the same level of custom error classes as redis-errors. Instead, it focuses on providing a comprehensive set of features for interacting with Redis.

node-redis

node-redis is another popular Redis client for Node.js. It includes basic error handling capabilities but lacks the specialized custom error classes provided by redis-errors. It is designed to be simple and easy to use for basic Redis operations.

README

redis-errors

All error classes used in node_redis from v.3.0.0 are in here. They can be required as needed.

Install

Install with NPM:

npm install redis-errors

Usage

const { ReplyError, InterruptError } = require('redis-errors');

// Using async await
try {
  await client.set('foo') // Missing value
} catch (err) {
  if (err instanceof InterruptError) {
    console.error('Command might have been processed')
  }
  if (err instanceof ReplyError) {
    // ...
  }
  throw err
}

// Using callbacks
client.set('foo', (err, res) => {
  if (err) {
    if (err instanceof InterruptError) {
      // ...
    }
  }
})

Error classes

All errors returned by NodeRedis use own Error classes. You can distinguish different errors easily by checking for these classes.

To know what caused the error they might contain properties to know in more detail what happened.

Each error contains a message, a name and a stack property. Please be aware that the stack might not be useful due to the async nature and is in those cases therefore limited to two frames.

There might be more not yet documented properties as well. Please feel free to open a pull request to document those as well.

RedisError

Properties:

Properties depend on the individual error.

All errors returned by NodeRedis (client) are RedisErrors.
Subclass of Error

ReplyError

Properties:

• args: The arguments passed to the command.
• command: The command name.
• code: The Redis error code. Redis itself uses some internal error codes.

All errors returned by Redis itself (server) will be a ReplyError.
Subclass of RedisError

ParserError

Properties:

• buffer: The raw buffer input stringified.
• offset: The character count where the parsing error occurred.

Parsing errors are returned as ParserError.
Subclass of RedisError Note: If you encounter one of these please report that error including the attached offset and buffer properties!

AbortError

Properties:

• args: The arguments passed to the command.
• command: The command name.

If a command was not yet executed but rejected, it'll return a AbortError.
Subclass of RedisError

InterruptError

Properties:

• args: The arguments passed to the command.
• command: The command name.
• origin: The original error that caused the interrupt

All executed commands that could not fulfill (e.g. network drop while executing) return a InterruptError.
Subclass of AbortError
Note: Interrupt errors can happen for multiple reasons that are out of the scope of NodeRedis itself. There is nothing that can be done on library side to prevent those.

License

MIT