# Go Language Documentation for OpenIM

In the realm of software development, especially within Go language projects, documentation plays a crucial role in ensuring code maintainability and ease of use. Properly written and accurate documentation is not only essential for understanding and utilizing software effectively but also needs to be easy to write and maintain. This principle is at the heart of OpenIM's approach to supporting commands and generating documentation.

## Supported Commands in OpenIM

OpenIM leverages Go language's documentation standards to facilitate clear and maintainable code documentation. Below are some of the key commands used in OpenIM for documentation purposes:

### `go doc` Command

The `go doc` command is used to print documentation for Go language entities such as variables, constants, functions, structures, and interfaces. This command allows specifying the identifier of the program entity to tailor the output. Examples of `go doc` command usage include:

- `go doc sync.WaitGroup.Add` prints the documentation for a specific method of a type in a package.
- `go doc -u -all sync.WaitGroup` displays all program entities, including unexported ones, for a specified type.
- `go doc -u sync` outputs all program entities for a specified package, focusing on exported ones without detailed comments.

### `godoc` Command

For environments lacking internet access, the `godoc` command serves to view the Go language standard library and project dependency library documentation in a web format. Notably, post-Go 1.12 versions, `godoc` is not part of the Go compiler suite. It can be installed using:

```shell
go get -u -v golang.org/x/tools/cmd/godoc
```

The `godoc` command, once running, hosts a local web server (by default on port 6060) to facilitate documentation browsing at http://127.0.0.1:6060. It generates documentation based on the GOROOT and GOPATH directories, showcasing both the project's own documentation and that of third-party packages installed via `go get`.

### Custom Documentation Generation Commands in OpenIM

OpenIM includes a suite of commands aimed at initializing, generating, and maintaining project documentation and associated files. Some notable commands are:

- `gen.init`: Initializes the OpenIM server project.
- `gen.docgo`: Generates missing `doc.go` files for Go packages, crucial for package-level documentation.
- `gen.errcode.doc`: Generates markdown documentation for OpenIM error codes.
- `gen.ca`: Generates CA files for all certificates, enhancing security documentation.

These commands underscore the project's commitment to thorough and accessible documentation, supporting both developers and users alike.

## Writing Your Own Documentation

When creating documentation for Go projects, including OpenIM, it's important to follow certain practices:

1. **Commenting**: Use single-line (`//`) and block (`/* */`) comments to provide detailed documentation within the code. Block comments are especially useful for package documentation, which should immediately precede the package statement without any intervening blank lines.

2. **Overview Section**: To create an overview section in the documentation, place a block comment directly before the package statement. This section should succinctly describe the package's purpose and functionality.

3. **Detailed Descriptions**: Comments placed before functions, structures, or variables will be used to generate detailed descriptions in the documentation. Follow the same commenting rules as for the overview section.

4. **Examples**: Include example functions prefixed with `Example` to demonstrate usage. Output from these examples can be documented at the end of the function, starting with `// Output:` followed by the expected result.

Through adherence to these documentation practices, OpenIM ensures that its codebase remains accessible, maintainable, and easy to use for developers and users alike.