What's the best way to bundle static resources in a Go program?

Issue

I’m working on a small web application in Go that’s meant to be used as a tool on a developer’s machine to help debug their applications/web services. The interface to the program is a web page that includes not only the HTML but some JavaScript (for functionality), images, and CSS (for styling). I’m planning on open-sourcing this application, so users should be able to run a Makefile, and all the resources will go where they need to go. However, I’d also like to be able to simply distribute an executable with as few files/dependencies as possible. Is there a good way to bundle the HTML/CSS/JS with the executable, so users only have to download and worry about one file?

---

Right now, in my app, serving a static file looks a little like this:

// called via http.ListenAndServe
func switchboard(w http.ResponseWriter, r *http.Request) {

    // snipped dynamic routing...

    // look for static resource
    uri := r.URL.RequestURI()
    if fp, err := os.Open("static" + uri); err == nil {
        defer fp.Close()
        staticHandler(w, r, fp)
        return
    }

    // snipped blackhole route
}
    

So it’s pretty simple: if the requested file exists in my static directory, invoke the handler, which simply opens the file and tries to set a good Content-Type before serving. My thought was that there’s no reason this needs to be based on the real filesystem: if there were compiled resources, I could simply index them by request URI and serve them as such.

Let me know if there’s not a good way to do this or I’m barking up the wrong tree by trying to do this. I just figured the end-user would appreciate as few files as possible to manage.

^{If there are more appropriate tags than go, please feel free to add them or let me know.}

Solution

The go-bindata package looks like it might be what you’re interested in.

https://github.com/go-bindata/go-bindata

It will allow you to convert any static file into a function call that can be embedded in your code and will return a byte slice of the file content when called.

Answered By – Daniel

Answer Checked By – Timothy Miller (GoLangFix Admin)