encode struct as JSON, and use it in http.NewRequest ( io.Writer vs. io.Reader issue )H

[Lax Clarke]

Hi,

I want to marshall a struct as JSON and use it in an http.NewRequest.

The problem is, encoding/json package provides NewEncoder, but that works on an io.Writer

(see: https://golang.org/pkg/encoding/json/#NewEncoder)

While, http.NewRequest accepts an io.Reader as the body of request.

(see: https://golang.org/pkg/net/http/#NewRequest)

So, what's the best way to take a golang struct and marshal it as a JSON body of an http request?

Thanks.

[Matt Harden]

You could use bytes.Buffer to encode it into a buffer beforehand and then pass that as the body, or you could use an io.Pipe which essentially connects a Reader to a Writer, which allows you to encode on the fly as the http client reads the body to send it along. However I think encoding/json may already buffer the whole contents of the JSON anyway so using io.Pipe might not help int that regard. It's probably simplest and clearest to use the Buffer.

--
You received this message because you are subscribed to the Google Groups "golang-nuts" group.
To unsubscribe from this group and stop receiving emails from it, send an email to golang-nuts...@googlegroups.com.
For more options, visit https://groups.google.com/d/optout.

[Shawn Milochik]

How about https://golang.org/pkg/bytes/#NewReader ?

[Edward Muller]

See also https://golang.org/pkg/io/#Pipe

On Sat, Oct 1, 2016 at 9:13 PM Shawn Milochik <shawn...@gmail.com> wrote:

How about https://golang.org/pkg/bytes/#NewReader ?