Auto merge of #1728 - bryanburgers:fix-ember-assertion-error, r=sgrif

Fix assertion error in Ember for version downloads

Fix the following assertion error that occurs when running the frontend in debug mode, which cause graphs to not display at all.

> Assertion Failed: You must include an 'id' for version-download in an object passed to 'push'

This has been happening since 3c92ca2 landed.

The fix involves telling Ember how to create a unique ID for a version-download object, using the composite key.

I haven't been able to confirm, but I believe this is the reason that graphs in production are only ever counting/displaying a single version. When using this change locally in debug mode against the live website, the downloads graphs are rendering correctly.

Fixes #1704.

Author: bors

app/serializers/version-download.js

@@ -0,0 +1,7 @@
+import DS from 'ember-data';
+
+export default DS.RESTSerializer.extend({
+    extractId(modelClass, resourceHash) {
+        return `${resourceHash.date}-${resourceHash.version}`;
+    },
+});