How to Automatically Open a Browser After a Go Server Starts Listening?

How to Launch the Browser After Server Startup in Go

When building web applications in Go, it may be necessary to start the browser after the server has begun listening for connections. This article provides a straightforward method to address this requirement.

Original Code

The provided code snippet sets up a basic HTTP server using the httprouter library. However, it prematurely attempts to open the browser before the server has fully initialized:

r := httprouter.New()
r.GET("/test", func(w http.ResponseWriter, r *http.Request, _ httprouter.Params) {
    fmt.Fprint(w, "Welcome!\n")
})
http.ListenAndServe("localhost:3000", r)
fmt.Println("ListenAndServe is blocking")
open.RunWith("http://localhost:3000/test", "firefox")

Solution

To open the browser after the server has started listening, modify the code as follows:

l, err := net.Listen("tcp", "localhost:3000")
if err != nil {
    log.Fatal(err)
}

// The browser can connect now because the listening socket is open.

err = open.Start("http://localhost:3000/test")
if err != nil {
    log.Println(err)
}

// Start the blocking server loop.

log.Fatal(http.Serve(l, r))

This revised code separates the steps of opening the listener and starting the server loop. It allows the browser to connect before the blocking http.Serve call is made. Thus, the browser opens after the server has started listening successfully.

The above is the detailed content of How to Automatically Open a Browser After a Go Server Starts Listening?. For more information, please follow other related articles on the PHP Chinese website!