Expand typing and comments for sidebar-config types

src/sidebar/config/build-settings.js

@@ -4,6 +4,8 @@ import * as postMessageJsonRpc from '../util/postmessage-json-rpc';
 
 /**
  * @typedef {import('../../types/config').ConfigFromHost} ConfigFromHost
+ * @typedef {import('../../types/config').ConfigFromAnnotator} ConfigFromAnnotator
+ * @typedef {import('../../types/config').ConfigFromEmbedder} ConfigFromEmbedder
  * @typedef {import('../../types/config').ConfigFromSidebar} ConfigFromSidebar
  * @typedef {import('../../types/config').RPCSettings} RPCSettings
  * @typedef {import('../../types/config').SidebarSettings} SidebarSettings
@@ -71,9 +73,9 @@ function fetchServiceGroups(configFromHost, rpcSettings) {
 }
 
 /**
- * Derive RPC settings from the provided `ConfigFromHost`, if any are present.
+ * Derive RPC settings from the provided `AnnotatorConfigFromHost`, if any are present.
  *
- * @param {ConfigFromHost} configFromHost
+ * @param {ConfigFromAnnotator} configFromHost
  * @param {Window} window_
  * @return {import('../../types/config').RPCSettings|null}
  */
@@ -99,11 +101,11 @@ function buildRPCSettings(configFromHost, window_) {
  * Retrieve ConfigFromHost to use for settings from the ancestor frame indicated
  * in `rpcSettings`
  *
- * @param {ConfigFromHost} hostConfigFromURL
+ * @param {ConfigFromAnnotator} hostConfigFromURL
  * @param {RPCSettings} rpcSettings
- * @return {Promise<ConfigFromHost>}
+ * @return {Promise<ConfigFromEmbedder>}
  */
-async function getHostConfigByRPC(hostConfigFromURL, rpcSettings) {
+async function getEmbedderConfig(hostConfigFromURL, rpcSettings) {
   const hostConfigFromFrame = await postMessageJsonRpc.call(
     rpcSettings.targetFrame,
     rpcSettings.origin,
@@ -140,21 +142,21 @@ async function getHostConfigByRPC(hostConfigFromURL, rpcSettings) {
  * @return {Promise<SidebarSettings>} - The merged settings
  */
 export async function buildSettings(configFromSidebar, window_ = window) {
-  const hostConfigFromURL = hostPageConfig(window);
+  const annotatorConfigFromHost = hostPageConfig(window);
 
-  const rpcSettings = buildRPCSettings(hostConfigFromURL, window_);
+  const rpcSettings = buildRPCSettings(annotatorConfigFromHost, window_);
   let configFromHost;
   if (rpcSettings) {
     // The presence of RPCSettings indicates that we should
     // source the ConfigFromHost from another frame, and potentially load
     // the correct groups asynchronously as well.
-    const hostConfigFromFrame = await getHostConfigByRPC(
-      hostConfigFromURL,
+    const hostConfigFromFrame = await getEmbedderConfig(
+      annotatorConfigFromHost,
       rpcSettings
     );
     configFromHost = fetchServiceGroups(hostConfigFromFrame, rpcSettings);
   } else {
-    configFromHost = hostConfigFromURL;
+    configFromHost = annotatorConfigFromHost;
   }
 
   /** @type {SidebarSettings} */

src/sidebar/config/host-config.js

@@ -6,14 +6,14 @@ import {
   toString,
 } from '../../shared/type-coercions';
 
-/** @typedef {import('../../types/config').ConfigFromHost} ConfigFromHost */
+/** @typedef {import('../../types/config').ConfigFromAnnotator} ConfigFromAnnotator */
 
 /**
  * Return the app configuration specified by the frame embedding the Hypothesis
  * client.
  *
  * @param {Window} window
- * @return {ConfigFromHost}
+ * @return {ConfigFromAnnotator}
  */
 export function hostPageConfig(window) {
   const config = parseConfigFragment(window.location.href);

src/types/config.js

@@ -54,13 +54,33 @@
  */
 
 /**
- * @typedef RequestConfigFromFrameOptions
+ * May be provided by `ConfigFromAnnotator` to configure a known ancestor
+ * frame as the "embedder" frame. `ConfigFromEmbedder` will be requested from
+ * this frame, and additional messaging (via postMessage) may be configured
+ * between the sidebar frame and this embedder frame.
+ *
+ * @typedef EmbedderFrameConfig
  * @prop {number} ancestorLevel
  * @prop {string} origin
  */
 
 /**
- * Configuration set by the embedder of the client and used by the sidebar.
+ * An "embedder frame" may provide configuration to be notified (via JSON RPC)
+ * of qualifying annotation activity from the sidebar frame.
+ *
+ * @typedef {'create'|'save'|'delete'} AnnotationActivityEvent
+ *
+ * @typedef ReportAnnotationActivityConfig
+ *   @prop {string} method - Name of method to call in embedder frame on
+ *     qualifying annotation activity
+ *   @prop {AnnotationActivityEvent[]} events - Which events to notify about
+ *
+ */
+
+/**
+ * Configuration provided by the annotator ("host frame") as
+ * `ConfigFromAnnotator` OR by an ancestor ("embedder frame") as
+ * `ConfigFromEmbedder`.
  *
  * This is the subset of keys from
  * https://h.readthedocs.io/projects/client/en/latest/publishers/config/ which
@@ -77,8 +97,12 @@
  *   Theme properties (fonts, colors etc.)
  * @prop {boolean} [enableExperimentalNewNoteButton] -
  *   Whether to show the "New note" button on the "Page Notes" tab
- * @prop {RequestConfigFromFrameOptions} [requestConfigFromFrame]
- *   Origin of the ancestor frame to request configuration from
+ * @prop {EmbedderFrameConfig} [requestConfigFromFrame] - Allows annotator to
+ *   designate an ancestor frame from which configuration should be requested.
+ *   Only valid when provided by annotator ("host frame").
+ * @prop {ReportAnnotationActivityConfig} [reportActivity] - Allows embedder to
+ *   receive notifications on qualifying annotation activity. Only valid when
+ *   provided by ancestor ("embedder frame").
  * @prop {Service[]} [services] -
  *   Configuration for the annotation services that the client connects to
  * @prop {string} [theme]
@@ -88,18 +112,67 @@
  */
 
 /**
- * RPC settings derived from `ConfigFromHost['requestConfigFromFrame']`
+ * Settings derived from `ConfigFromAnnotator["requestConfigFromFrame"]`.
+ * These settings allow `ConfigFromEmbedder` to be requested from the
+ * designated frame, and allows subsequent communication between the sidebar
+ * and embedder frames.
  *
  * @typedef RPCSettings
  * @prop {Window} targetFrame
- * @prop {RequestConfigFromFrameOptions['origin']} origin
+ * @prop {EmbedderFrameConfig['origin']} origin
  */
 
 /**
- * The `settings` object used in the sidebar app that is a result of merging
- * (filtered and validated) configuration from the host page with configuration
- * from h / the browser extension.
+ * `SidebarSettings` are created by merging "sidebar configuration"
+ * (`ConfigFromSidebar`) with  "host configuration" (either
+ * `ConfigFromAnnotator` OR `ConfigFromEmbedder`).
+ *
+ * In all cases, the annotator ("host frame") provides `ConfigFromAnnotator`
+ * to the sidebar frame by encoding values into a URL fragment on the sidebar
+ * frame's `src` attribute.
+ *
+ * In most cases, `SidebarSettings` combine `ConfigFromAnnotator` with
+ * `ConfigFromSidebar`:
+ *
+ * +--------------------------------------------+
+ * |        host frame (annotator)              |
+ * |                 +-----------------------+  |
+ * |                 |  sidebar frame        |  |
+ * |                 |                       |  |
+ * | <ConfigFromAnnotator> => iframe.src     |  |
+ * |                 |                       |  |
+ * |                 |                       |  |
+ * |                 |                       |  |
+ * |                 | <ConfigFromSidebar>   |  |
+ * |                 +-----------------------+  |
+ * +--------------------------------------------+
+ *
+ * In some cases (e.g. LMS), host configuration should instead be provided by an
+ * ancestor ("embedder") frame. This is signaled by the presence of a valid
+ * `requestConfigFromFrame` object on `ConfigFromAnnotator`.
+ *
+ * `ConfigFromEmbedder` will then be requested from the designated embedder
+ * frame and combined with `ConfigFromSidebar` to produce `SidebarSettings`:
+ *
+ * +------------------------------------------------------------------------+
+ * |                                         embedder frame                 |
+ * |  +------------------------------------------+                          |
+ * |  |        host frame (annotator)            |                          |
+ * |  |                 +---------------------+  |                          |
+ * |  |                 |  sidebar frame      |  |                          |
+ * |  |                 |                     |  |                          |
+ * |  | <ConfigFromAnnotator> => iframe.src   |  |                          |
+ * |  |   requestConfigFromFrame              |  |                          |
+ * |  |                 |                     |  |                          |
+ * |  |                 |                     |  |                          |
+ * |  |                 |       <====postMessage====> <ConfigFromEmbedder>  |
+ * |  |                 | <ConfigFromSidebar> |  |                          |
+ * |  |                 +---------------------+  |                          |
+ * |  +------------------------------------------+                          |
+ * +------------------------------------------------------------------------+
  *
+ * @typedef {Omit<ConfigFromHost, "reportActivity">} ConfigFromAnnotator
+ * @typedef {Omit<ConfigFromHost, "requestConfigFromFrame">} ConfigFromEmbedder
  * @typedef {ConfigFromHost & ConfigFromSidebar & { rpc?: RPCSettings }} SidebarSettings
  */