> For the complete documentation index, see [llms.txt](https://go-macaron.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://go-macaron.com/middlewares/switcher.md).

# Serving Multiple Sites

Module switcher provides host switch functionality for [Macaron](https://github.com/go-macaron/macaron).

* [GitHub](https://github.com/go-macaron/switcher)
* [API Reference](https://gowalker.org/github.com/go-macaron/switcher)

## Installation

```bash
go get github.com/go-macaron/switcher
```

## Usage

If you want to run 2 instances in one program, Host Switcher is the feature you're looking for.

```go
func main() {
    m1 := macaron.Classic()
    // Register m1 middlewares and routers.

    m2 := macaron.Classic()
    // Register m2 middlewares and routers.

    hs := switcher.NewHostSwitcher()
    // Set instance corresponding to host address.
    hs.Set("gowalker.org", m1)
    hs.Set("gogs.io", m2)
    hs.Run()
}
```

By default, this program will listen on ports `4000`(for `m1`) and `4001`(for `m2`) in `macaron.DEV` mode just for convenience. And only listen on `4000` in `macaron.PROD` mode.

### Dynamic match

In case you have different subdomains that need only one Macaron instance:

```go
// ...
m := macaron.Classic()
// Register m middlewares and routers.

hs := macaron.NewHostSwitcher()
// Set instance corresponding to host address.
hs.Set("*.example.com", m)
hs.Run()
// ...
```


---

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