Using the net/http package in go

When I started picking up the go language years ago, things that stood out to me immediately were the io and net/http packages. Both of those packages were extremely well done and minimal in the amount of interfaces they exposed to the user.

What I love about net/http

The two things which stand out for me are:

1. Interface Design.
2. Composability

Interface Design

The primary constructs you’ll interact with are pretty limited:

To build your service:

http.Handler
http.HandlerFunc
http.Server

To handle requests:

http.ResponseWriter
http.Request

To build a client:

http.Client
http.Transport

In total, we’re looking at 7 core primitives to build a client and server — which isn’t a lot!

Composability

When it comes to building HTTP services, the main things users need likely fall into two buckets:

1. Defining what handlers to run based on a method, or path.
2. Defining middleware to be executed.

Here’s an example showing this composability in action [1] [2]:

• In this miniature example, we can see that the authenticate middleware is doing authentication for us.
• Similarly, we handle path routing by specifying the prefix to use for each handler.

Testing your service

From this example, testing your service would be pretty straightforward:

Conclusion

As we can see, getting started with the net/http package is extremely simple but packs a lot of punch.

In a followup article, I’ll share more about using http.Client as the unit of integration for building HTTP clients.

Footnotes

• [1]: For brevity, we’ve chosen to use http.HandlerFunc in our code example, but in practice, or in production, we’d always want to use http.Handler since we can convert an http.HandlerFunc to it easily.
• [2]: Similarly, we would want to handle graceful shutdown of the http server so we’d want to utilize the Shutdown method of the http.Server primitive.