hiredis vs redis: What are the differences?

Introduction

Hiredis and Redis are both libraries used for working with Redis databases. They provide different functionalities and have certain key differences.

1. Protocol Support: Hiredis is a minimalistic C client library that focuses on supporting the Redis protocol. It provides a simple and efficient way to send commands and receive responses from a Redis server. In contrast, Redis is a full-fledged in-memory data store, supporting not only the Redis protocol but also additional data structures, data persistence, and advanced features like Pub/Sub and Lua scripting.

2. API Complexity: Hiredis has a simpler API compared to Redis. It provides a straightforward set of functions to send commands, parse responses, and manage connections to Redis servers. Redis, on the other hand, offers a more comprehensive API with a wide range of functions to manipulate data structures, perform transactions, handle server configurations, and manage keys and namespaces.

3. Network Handling: Hiredis relies on external network libraries for network I/O, such as libevent, libuv, or simple file descriptors. It doesn't have built-in support for connection pooling or high-level abstractions for distributed setups. Redis, on the other hand, includes its own networking layer and provides features like connection pooling, auto-reconnection, and cluster support.

4. Language Support: Hiredis is primarily focused on providing a C API for Redis, but it also supports bindings for other languages like Python, Lua, and Rust. Redis, on the other hand, has native support for a wide range of programming languages including C, Python, Ruby, Node.js, Java, and more. Redis clients in different languages may have varying degrees of feature parity and functionality.

5. Project Maturity and Community: Hiredis is a lightweight library with a smaller codebase and a narrower scope, which can make it easier to understand and maintain. It is actively used and maintained by the Redis community as part of the Redis project. Redis, being a full-fledged database system, has a larger and more mature codebase with continuous development and a large community of contributors and users.

6. Performance Considerations: Hiredis aims for minimal overhead and high performance by focusing on low-level Redis protocol parsing and efficient I/O operations. Redis, being a more feature-rich system, may have some additional overhead due to the extra abstractions and functionalities it provides. However, Redis is designed to handle high-performance scenarios and offers optimizations like replication, sharding, and clustering for scaling and performance.

In Summary, Hiredis is a lightweight C client library with a focus on Redis protocol support, simplicity, and low-level efficiency. Redis, on the other hand, is a full-featured in-memory data store with extensive functionality, native language support, networking capabilities, and a larger community.