What could happen if I don't close response.Body?

Question

In Go, I have some http responses and I sometimes forget to call:

resp.Body.Close()

What happens in this case? will there be a memory leak

Answer 1

If Response.Body won't be closed with Close() method than a resources associated with a fd won't be freed. This is a resource leak.

Closing Response.Body

From response source:

It is the caller's responsibility to close Body.

So there is no finalizers bound to the object and it must be closed explicitly.

Error handling and deferred cleanups

On error, any Response can be ignored. A non-nil Response with a non-nil error only occurs when CheckRedirect fails, and even then the returned Response.Body is already closed.

resp, err := http.Get("http://example.com/")
if err != nil {
    // Handle error if error is non-nil
}
defer resp.Body.Close() // Close body only if response non-nil