correctly format code metadata in telemetry events

Author: Christopher Willis-Ford

package-lock.json

@@ -45,6 +45,7 @@
     "eslint-plugin-import": "^2.18.0",
     "eslint-plugin-react": "^7.14.2",
     "intl": "1.2.5",
+    "lodash.defaultsdeep": "^4.6.1",
     "mkdirp": "^0.5.1",
     "nets": "^3.2.0",
     "react": "16.2.0",

package.json

@@ -1,18 +1,21 @@
 import {app, ipcMain} from 'electron';
+import defaultsDeep from 'lodash.defaultsdeep';
 
 import TelemetryClient from './telemetry/TelemetryClient';
 
 const EVENT_TEMPLATE = {
     version: '3.0.0',
     projectName: '',
     language: '',
-    scriptCount: -1,
-    spriteCount: -1,
-    variablesCount: -1,
-    blocksCount: -1,
-    costumesCount: -1,
-    listsCount: -1,
-    soundsCount: -1
+    metadata: {
+        scriptCount: -1,
+        spriteCount: -1,
+        variablesCount: -1,
+        blocksCount: -1,
+        costumesCount: -1,
+        listsCount: -1,
+        soundsCount: -1
+    }
 };
 
 const APP_ID = 'scratch-desktop';
@@ -42,19 +45,28 @@ class ScratchDesktopTelemetry {
     }
 
     projectDidLoad (metadata = {}) {
-        this._telemetryClient.addEvent('project::load', {...EVENT_TEMPLATE, ...metadata});
+        this._telemetryClient.addEvent('project::load', this._buildMetadata(metadata));
     }
 
     projectDidSave (metadata = {}) {
-        this._telemetryClient.addEvent('project::save', {...EVENT_TEMPLATE, ...metadata});
+        this._telemetryClient.addEvent('project::save', this._buildMetadata(metadata));
     }
 
     projectWasCreated (metadata = {}) {
-        this._telemetryClient.addEvent('project::create', {...EVENT_TEMPLATE, ...metadata});
+        this._telemetryClient.addEvent('project::create', this._buildMetadata(metadata));
     }
 
     projectWasUploaded (metadata = {}) {
-        this._telemetryClient.addEvent('project::upload', {...EVENT_TEMPLATE, ...metadata});
+        this._telemetryClient.addEvent('project::upload', this._buildMetadata(metadata));
+    }
+
+    _buildMetadata (metadata) {
+        const { projectName, language, ...codeMetadata } = metadata;
+        return defaultsDeep({
+            projectName,
+            language,
+            metadata: codeMetadata
+        }, EVENT_TEMPLATE);
     }
 }