Emitter Should Optionally Be Static

Describe the Bug

The HTTP Emitter should have static methods such that we don’t need to construct multiple Emitters before sending our CE.

Currently we must instantiate the Emitter with a URL and then emit. See README.

const { CloudEvent, Emitter } = require("cloudevents");

const ce = new CloudEvent({ type, source, data });
async function test() {
  const emitter = new Emitter({
    url: "https://cloudevents.io/example"
  });
  await emitter.send(ce);
}

Expected Behavior

Like the static Receiver.accept(...), I’d imagine an Emitter.send(...).

const { CloudEvent, Emitter } = require("cloudevents");

const ce = new CloudEvent({ type, source, data });
async function test() {
  await Emitter.send(ce, "https://cloudevents.io/example");
}

This format is more idiomatic and is similar to the format for what other npm modules do:

• http Standard library – (http.request(url, options))
• axios - (axios.post(url, options))
• request - (request.post({ url, ...options }))
• superagent - (superagent.post(url).send(body).end((err, res) => {}))

[lholmquist]

@grant i would suggest to send a PR with the proposed changes. Maybe seeing the code in context might help

[matejvasek]

I think that instance of Emitter is supposed to be used only locally in single file (or even function) and not being exported.