tests(static-server): allow hook to modify response body

[connorjclark]

This hook is needed to modify the URLs in the fixtures for running smoke tests on Lightrider in CI.

Googlers: see cl/275909869 / doc

[patrickhulce]

I'm going to dismiss my review request @brendankenny this is all you since it's a large change to be unable to see the context for :)

[brendankenny]

I'm going to dismiss my review request @brendankenny this is all you since it's a large change to be unable to see the context for :)

string -> string transformations (e.g. replace on a regex) could make it so even innocuous changes break things (let alone future refactors). It would be great to get an idea of the decision/constraint space so we could evaluate if there are other alternatives (or just what to document so future folks know which live wires not to touch).

[connorjclark]

This is just meant to change the port numbers on URLs, so the hook could be less generic and be specifically replacePort(original, new) or sumthin.

We can follow up on this after I write / we discuss a doc re: the whole integration testing story.

[connorjclark]

The first post was updated with the relevant doc (@patrickhulce, nothing has changed since you last reviewed the doc)

I don't think knowing the usage internally is necessary for reviewing this change. The idea is just that the ports must be configurable (the internal test is assigned 2 free ports, and they are random). replacePort is the stricter way to do it, the current PR is the most generic way to do it. I don't see this static test server being consumed by anyone but ourselves, so perhaps the generic solution is fine?

[patrickhulce]

I think we'll need a story for how to exercise the other integration parts of this that are smokerider-specific.

The generic port part LGTM, but I don't feel very confident in my ability to review the other bits.

[patrickhulce]

Also I've since learned it's a Goog holiday so no need to reply @connorjclark, sorry :)

[patrickhulce]

LGTM

[patrickhulce]

fwiw, we already have isomorphic-fetch in our devDeps that should make this much easier :)

const fetch = require('isomorphic-fetch')
const get = url => fetch(url).then(r => r.text())

[connorjclark]

so fetch