refactor: relationships are expressed as objects {id} rather than string ID fields

addons/api/addon/serializers/application.js

@@ -30,7 +30,7 @@ export default class ApplicationSerializer extends RESTSerializer {
    * @return {string}
    */
   keyForRelationship(rel) {
-    return `${underscore(rel)}_id`;
+    return underscore(rel);
   }
 
   /**
@@ -137,4 +137,19 @@ export default class ApplicationSerializer extends RESTSerializer {
     );
   }
 
+  /**
+   * Returns the default extraction with one difference.  If the extracted
+   * relationship does not include a `type` field as required by JSON API
+   * (the Ember internal record representation), one is added.
+   * @override
+   * @param {Object} relationshipModelName
+   * @param {Object} relationshipHash
+   * @return {Object}
+  */
+  extractRelationship(relationshipModelName/*, relationshipHash*/) {
+    const relationship = super.extractRelationship(...arguments);
+    if (!relationship.type) relationship.type = relationshipModelName;
+    return relationship;
+  }
+
 }

addons/api/tests/unit/models/scope-test.js

@@ -19,11 +19,11 @@ module('Unit | Model | scope', function(hooks) {
     this.server.get('/v1/scopes', () => ({
       items: [
         {id: 'global', type: 'global'},
-        {id: 'o_1', type: 'org', scope_id: 'global'},
-        {id: 'o_2', type: 'org', scope_id: 'global'},
-        {id: 'p_1', type: 'project', scope_id: 'o_1'},
-        {id: 'p_2', type: 'project', scope_id: 'o_1'},
-        {id: 'p_3', type: 'project', scope_id: 'o_2'}
+        {id: 'o_1', type: 'org', scope: {id: 'global'}},
+        {id: 'o_2', type: 'org', scope: {id: 'global'}},
+        {id: 'p_1', type: 'project', scope: {id: 'o_1'}},
+        {id: 'p_2', type: 'project', scope: {id: 'o_1'}},
+        {id: 'p_3', type: 'project', scope: {id: 'o_2'}},
       ]
     }));
     const scopes = await store.findAll('scope');