How to contribute to the Mongoose open source project

Understanding the Mongoose Open-Source Project

Mongoose is a lightweight networking library that supports multiple protocols, including HTTP, WebSocket, and MQTT. It is developed and open-sourced by Cesanta and is widely used in embedded systems and server-side development. Contributing to Mongoose not only enhances your technical skills but also brings tangible value to the community. To get started, familiarize yourself with Mongoose's core features and code structure by reading the official documentation and source code.

Setting Up the Development Environment

Before contributing, you need to set up a local development environment. Mongoose is primarily written in C but also offers bindings for other languages (e.g., JavaScript, Python). Here are the steps to set up the environment:

1. Clone the Repository:

   git clone https://github.com/cesanta/mongoose
   cd mongoose
   

2. Install Dependencies:

   • For C development, ensure gcc or clang is installed.
   • For other language bindings, install the corresponding toolchain (e.g., Node.js, Python).

3. Compile and Test:

   make clean all
   

Understanding the Contribution Process

Mongoose follows the standard GitHub open-source contribution process:

1. Fork the Repository: Fork the official repository to your personal GitHub account.
2. Create a Branch: Create a new branch based on the latest master branch, with a clear name (e.g., fix-http-parser).
3. Commit Changes: Make your changes, commit them to your local branch, and push to your remote repository.
4. Submit a PR: Create a Pull Request on GitHub, describing the changes and their motivation.

Common Types of Contributions

Fixing Bugs

You can find open bugs on the GitHub Issues page. For example, if you discover a boundary condition issue in the HTTP parser:

// Example: Fixing HTTP header parsing logic
if (end - p > MG_MAX_HTTP_HEADERS) {
  return -1; // Original code might not handle oversized headers
}

Adding New Features

Discuss new features with the maintainers before implementation. For example, adding compression support for WebSocket:

// Example: Extending WebSocket handshake logic
int mg_ws_compress_handshake(struct mg_connection *c) {
  // Implement compression handshake logic
}

Improving Documentation

Documentation updates are a great way to start contributing. For example, adding usage examples for an API:

### `mg_http_listen()`
Example of starting an HTTP server:
```c
struct mg_mgr mgr;
mg_mgr_init(&mgr);
mg_http_listen(&mgr, "0.0.0.0:8000", fn, NULL);

Code Style and Testing

Mongoose has strict code style requirements:

• Use 2 spaces for indentation.
• Function names should be in snake_case.
• Comments should be clear and concise.

Ensure all tests pass before submitting:

make test

New features must include corresponding unit tests. For example, testing a new API:

TEST_CASE("test_ws_compress") {
  struct mg_connection c;
  ASSERT(mg_ws_compress_handshake(&c) == 0);
}

Participating in Community Discussions

Active contributors can join the community Slack or mailing list to participate in design discussions. For example, voting on new protocol support:

Proposal: Add CoAP protocol support
- [ ] Yes
- [ ] No

Handling PR Feedback

Maintainers may request changes to your code. For example:

1. Adjusting the interface design.
2. Adding more test cases.
3. Fixing code style issues.

Respond promptly and update your PR accordingly.