Is it possible to trigger programmatically a ember mirage request response - testing

Question

I use Ember mirage in my tests. I need to check the state of my tested component after a request has been send but before the respond has been received.
How it is possible to configure my test to avoid the mirage server responds automatically and trigger the response programmatically?
I used to do that with sinonjs but I do not find the way to manage this use case with Ember mirage. It is possible?

Answer 1

http://www.ember-cli-mirage.com/docs/v0.3.x/route-handlers/
You can add a handler like this inside your test:
server.get('/users/:id', function(db, request) {
console.log(request) // to debug request/response
return db.users.find(request.params.id);
});

Answer 2

If I understand your question correctly, you are trying to test a situation on the page (acceptance test) when data were sent to the server but the response still did not arrive.
It is possible to access server instance in your test, so it is not that complicated to create your own method that will pause/resume responding but the simpler option (that I use as well) is just to postpone response from mirage using timing option (http://www.ember-cli-mirage.com/docs/v0.3.x/configuration/#timing). Then, when you do your tests before andThen() you should be in a situation that you wish to test.

Answer 3

you can access the underlying pretender instance and the fact that mirage just passes the timing parameter straight through to the pretender request.
https://github.com/pretenderjs/pretender#timing-parameter
Unfortunately pretender doesn't have docs for requestReferences and requiresManualResolution(verb, path), but this helper function will process all outstanding manual requests
function resolveManualPretenderRequests(pretender) {
pretender.requestReferences.forEach((ref) => {
if (pretender.requiresManualResolution(ref.request.method, ref.request.url)) {
pretender.resolve(ref.request);
}
});
}
Then you can just use mirage to register a manual request handler
server.get('/models:id', { timing: true });
so in an example test, you can use the ember test helper waitFor() to do something like
test('button is disabled while loading', async function(assert) {
assert.expect(2);
// passing true to timing tells the underlying pretender handler wait for the request to be manually processed
server.get('/models/:id', { timing: true });
// await render will wait for promises to settle, but we actually don't want that
const renderPromise = render(hbs`<MyComponent />`);
// the waitFor() helper instead will allow us to just wait for our button to render
await waitFor('button');
const button = this.element.querySelector('button');
// since the request has not resolved yet, the button is disabled
assert.strictEqual(button.disabled, true);
// then we manually resolve the request
resolveManualPretenderRequests(server.pretender);
// now we can await the render so that we get our updated button state
await renderPromise;
// with the request resolved, now the button is no longer disabled
assert.strictEqual(button.disabled, false);
});