Save context metadata provided by LMS app with new annotations

When the embedder frame (eg. our LMS app) provides context metadata to be saved
with annotations via the `annotationMetadata` config property, save that with
new annotations in the `metadata` field.

We add this information only when an annotation is created, and not on
subsequent edits, because the main use case in the LMS context is to record the
assignment where the annotation was created. If the user edits that annotation
subsequently in another assignment, we don't want it to be "moved" by updating
the `metadata` field.

Part of hypothesis/lms#5698

src/sidebar/services/annotations.ts

@@ -5,7 +5,7 @@ import type {
   Annotation,
   SavedAnnotation,
 } from '../../types/api';
-import type { AnnotationEventType } from '../../types/config';
+import type { AnnotationEventType, SidebarSettings } from '../../types/config';
 import * as metadata from '../helpers/annotation-metadata';
 import {
   defaultPermissions,
@@ -24,15 +24,18 @@ import type { APIService } from './api';
 export class AnnotationsService {
   private _activity: AnnotationActivityService;
   private _api: APIService;
+  private _settings: SidebarSettings;
   private _store: SidebarStore;
 
   constructor(
     annotationActivity: AnnotationActivityService,
     api: APIService,
+    settings: SidebarSettings,
     store: SidebarStore,
   ) {
     this._activity = annotationActivity;
     this._api = api;
+    this._settings = settings;
     this._store = store;
   }
 
@@ -109,6 +112,12 @@ export class AnnotationsService {
     if (metadata.isHighlight(annotation)) {
       annotation.permissions = privatePermissions(userid);
     }
+
+    // Attach information about the current context (eg. LMS assignment).
+    if (this._settings.annotationMetadata) {
+      annotation.metadata = { ...this._settings.annotationMetadata };
+    }
+
     return annotation;
   }
 

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

@@ -5,6 +5,7 @@ describe('AnnotationsService', () => {
   let fakeAnnotationActivity;
   let fakeApi;
   let fakeMetadata;
+  let fakeSettings;
   let fakeStore;
 
   let fakeDefaultPermissions;
@@ -46,6 +47,8 @@ describe('AnnotationsService', () => {
       isPublic: sinon.stub(),
     };
 
+    fakeSettings = {};
+
     fakeStore = {
       addAnnotations: sinon.stub(),
       annotationSaveFinished: sinon.stub(),
@@ -77,7 +80,12 @@ describe('AnnotationsService', () => {
       },
     });
 
-    svc = new AnnotationsService(fakeAnnotationActivity, fakeApi, fakeStore);
+    svc = new AnnotationsService(
+      fakeAnnotationActivity,
+      fakeApi,
+      fakeSettings,
+      fakeStore,
+    );
   });
 
   afterEach(() => {
@@ -118,6 +126,21 @@ describe('AnnotationsService', () => {
       assert.equal(annotation.user, 'acct:[email protected]');
       assert.isOk(annotation.$tag);
       assert.isString(annotation.$tag);
+
+      // `annotationMetadata` config not set, so this field should also not be set.
+      assert.isUndefined(annotation.metadata);
+    });
+
+    it('adds metadata from `annotationMetadata` setting to annotation', () => {
+      fakeStore.focusedGroupId.returns('mygroup');
+      fakeSettings.annotationMetadata = {
+        lms: { assignment_id: '1234' },
+      };
+
+      svc.create({}, now);
+
+      const annotation = getLastAddedAnnotation();
+      assert.deepEqual(annotation.metadata, fakeSettings.annotationMetadata);
     });
 
     describe('annotation permissions', () => {

src/types/api.ts

@@ -213,6 +213,15 @@ export type APIAnnotationData = {
   };
 
   user_info?: UserInfo;
+
+  /**
+   * An opaque object that contains metadata about the current context,
+   * provided by the embedder via the `annotationMetadata` config.
+   *
+   * The Hypothesis LMS app uses this field to attach information about the
+   * current assignment, course etc. to annotations.
+   */
+  metadata?: object;
 };
 
 /**

src/types/config.ts

@@ -231,6 +231,15 @@ export type ConfigFromAnnotator = ConfigFromHost & {
  * allow arbitrary web pages to set.
  */
 export type ConfigFromEmbedder = ConfigFromHost & {
+  /**
+   * Metadata about the context which the client should store with new
+   * annotations in the `metadata` field.
+   *
+   * The Hypothesis LMS app uses this field to attach information about the
+   * current assignment, course etc. to annotations.
+   */
+  annotationMetadata?: object;
+
   /**
    * Feature flags to enable. When a flag is listed here, it will be turned
    * on even if disabled in the H user profile.