Add helper functions to export all loaded annotations

src/shared/download-json-file.ts

+/**
+ * Download a file containing JSON-serialized `object` as `filename`
+ *
+ * @param data - JSON-serializable object
+ * @param _document - Test seam
+ * @return The contents of the downloaded file
+ * @throws {Error} If provided data cannot be JSON-serialized
+ */
+export function downloadJSONFile(
+  data: object,
+  filename: string,
+  /* istanbul ignore next */
+  _document = document
+): string {
+  const link = _document.createElement('a');
+  const fileContent = JSON.stringify(data, null, 2);
+  const blob = new Blob([fileContent], {
+    type: 'application/json',
+  });
+  const url = URL.createObjectURL(blob);
+
+  link.setAttribute('href', url);
+  link.setAttribute('download', filename);
+  link.style.visibility = 'hidden';
+
+  _document.body.appendChild(link);
+  link.click();
+  _document.body.removeChild(link);
+
+  return fileContent;
+}

src/shared/test/download-json-file-test.js

+import { downloadJSONFile } from '../download-json-file';
+
+describe('download-json-file', () => {
+  let fakeLink;
+  let fakeDocument;
+
+  beforeEach(() => {
+    fakeLink = {
+      setAttribute: sinon.stub(),
+      click: sinon.stub(),
+      style: {},
+    };
+
+    fakeDocument = {
+      createElement: sinon.stub().returns(fakeLink),
+      body: {
+        appendChild: sinon.stub(),
+        removeChild: sinon.stub(),
+      },
+    };
+  });
+
+  it('generates export file with provided annotations', () => {
+    const filename = 'my-file.json';
+    const data = { foo: ['bar', 'baz'] };
+
+    const fileContent = downloadJSONFile(data, filename, fakeDocument);
+
+    assert.equal(fileContent, JSON.stringify(data, null, 2));
+
+    assert.calledWith(fakeDocument.createElement, 'a');
+    assert.calledWith(fakeDocument.body.appendChild, fakeLink);
+    assert.calledWith(fakeDocument.body.removeChild, fakeLink);
+
+    assert.calledWith(
+      fakeLink.setAttribute.firstCall,
+      'href',
+      sinon.match.string
+    );
+    assert.calledWith(fakeLink.setAttribute.secondCall, 'download', filename);
+    assert.equal('hidden', fakeLink.style.visibility);
+  });
+});

src/sidebar/index.tsx

@@ -19,6 +19,7 @@ import {
 import { ServiceContext } from './service-context';
 import { AnnotationActivityService } from './services/annotation-activity';
 import { AnnotationsService } from './services/annotations';
+import { AnnotationsExporter } from './services/annotations-exporter';
 import { APIService } from './services/api';
 import { APIRoutesService } from './services/api-routes';
 import { AuthService } from './services/auth';
@@ -119,6 +120,7 @@ function startApp(settings: SidebarSettings, appEl: HTMLElement) {
 
   // Register services.
   container
+    .register('annotationsExporter', AnnotationsExporter)
     .register('annotationsService', AnnotationsService)
     .register('annotationActivity', AnnotationActivityService)
     .register('api', APIService)

src/sidebar/services/annotations-exporter.ts

+import type { Annotation } from '../../types/api';
+import { VersionData } from '../helpers/version-data';
+import type { SidebarStore } from '../store';
+
+export type ExportContent = {
+  export_date: string;
+  export_userid: string;
+  client_version: string;
+  annotations: Annotation[];
+};
+
+/**
+ * Generates annotations exports
+ *
+ * @inject
+ */
+export class AnnotationsExporter {
+  private _store: SidebarStore;
+
+  constructor(store: SidebarStore) {
+    this._store = store;
+  }
+
+  /**
+   * @param now - Test seam
+   */
+  buildExportContent(now = new Date()): ExportContent {
+    const profile = this._store.profile();
+    const annotations = this._store.allAnnotations();
+    const versionData = new VersionData(profile, []);
+
+    return {
+      export_date: now.toISOString(),
+      export_userid: profile.userid ?? '',
+      client_version: versionData.version,
+      annotations,
+    };
+  }
+}

src/sidebar/services/test/annotations-exporter-test.js

+import { AnnotationsExporter } from '../annotations-exporter';
+
+describe('AnnotationsExporter', () => {
+  let fakeStore;
+  let exporter;
+
+  beforeEach(() => {
+    fakeStore = {
+      profile: sinon.stub().returns({ userid: 'userId' }),
+      allAnnotations: sinon.stub(),
+    };
+    exporter = new AnnotationsExporter(fakeStore);
+  });
+
+  it('generates export content with provided annotations', () => {
+    const now = new Date();
+    const annotations = [{}, {}];
+    fakeStore.allAnnotations.returns(annotations);
+
+    const result = exporter.buildExportContent(now);
+
+    assert.deepEqual(result, {
+      export_date: now.toISOString(),
+      export_userid: 'userId',
+      client_version: '__VERSION__',
+      annotations,
+    });
+  });
+});