include the @gristlabs/grist-widget package, so Calendar is always available (#745)

The Calendar feature was implemented as a custom widget. To make it
available offline, we prepare a package that includes it, and add that
to Grist. The PluginManager is configured to find it.

An optional `GRIST_SKIP_BUNDLED_WIDGETS` flag is added to disable
widgets bundled this way from being used. This may be needed by
the tests in grist-widget to avoid getting an echo :-)

README.md

@@ -260,6 +260,7 @@ GRIST_SERVERS | the types of server to setup. Comma separated values which may c
 GRIST_SESSION_COOKIE | if set, overrides the name of Grist's cookie
 GRIST_SESSION_DOMAIN | if set, associates the cookie with the given domain - otherwise defaults to GRIST_DOMAIN
 GRIST_SESSION_SECRET | a key used to encode sessions
+GRIST_SKIP_BUNDLED_WIDGETS | if set, Grist will ignore any bundled widgets included via NPM packages.
 GRIST_ANON_PLAYGROUND    | When set to 'false' deny anonymous users access to the home page
 GRIST_FORCE_LOGIN    | Much like GRIST_ANON_PLAYGROUND but don't support anonymous access at all (features like sharing docs publicly requires authentication)
 GRIST_SINGLE_ORG | set to an org "domain" to pin client to that org

app/server/lib/FlexServer.ts

@@ -1998,8 +1998,13 @@ export class FlexServer implements GristServer {
     // Only used as {userRoot}/plugins as a place for plugins in addition to {appRoot}/plugins
     const userRoot = path.resolve(process.env.GRIST_USER_ROOT || getAppPathTo(this.appRoot, '.grist'));
     this.info.push(['userRoot', userRoot]);
-
+    // Some custom widgets may be included as an npm package called @gristlabs/grist-widget.
-    const pluginManager = new PluginManager(this.appRoot, userRoot);
+    const bundledRoot = isAffirmative(process.env.GRIST_SKIP_BUNDLED_WIDGETS) ? undefined : path.join(
+      getAppPathTo(this.appRoot, 'node_modules'),
+      '@gristlabs', 'grist-widget', 'dist'
+    );
+    this.info.push(['bundledRoot', bundledRoot]);
+    const pluginManager = new PluginManager(this.appRoot, userRoot, bundledRoot);
     // `initialize()` is asynchronous and reads plugins manifests; if PluginManager is used before it
     // finishes, it will act as if there are no plugins.
     // ^ I think this comment was here to justify calling initialize without waiting for

app/server/lib/PluginEndpoint.ts

@@ -46,7 +46,8 @@ function servePluginContent(req: express.Request, res: express.Response,
       req.get('X-From-Plugin-WebView') === "true" ||
       mimeTypes.lookup(path.extname(pluginPath)) === "application/javascript") {
     const dirs = pluginManager.dirs();
-    const contentRoot = pluginKind === "installed" ? dirs.installed : dirs.builtIn;
+    const contentRoot = pluginKind === "installed" ? dirs.installed :
+        (pluginKind === "builtIn" ? dirs.builtIn : dirs.bundled);
     // Note that pluginPath may not be safe, but `sendFile` with the "root" option restricts
     // relative paths to be within the root folder (see the 3rd party library unit-test:
     // https://github.com/pillarjs/send/blob/3daa901cf731b86187e4449fa2c52f971e0b3dbc/test/send.js#L1363)

app/server/lib/PluginManager.ts

@@ -14,9 +14,14 @@ export interface PluginDirectories {
    */
   readonly builtIn?: string;
   /**
-   * Directory where user installed plugins are localted.
+   * Directory where user installed plugins are located.
    */
   readonly installed?: string;
+  /**
+   * Yet another option, for plugins that are included
+   * during a build but not part of the codebase itself.
+   */
+  readonly bundled?: string;
 }
 
 /**
@@ -44,10 +49,12 @@ export class PluginManager {
    * @param {string} userRoot: path to user's grist directory; `null` is allowed, to only uses built in plugins.
    *
    */
-  public constructor(public appRoot?: string, userRoot?: string) {
+  public constructor(public appRoot?: string, userRoot?: string,
+                     public bundledRoot?: string) {
     this._dirs = {
       installed: userRoot ? path.join(userRoot, 'plugins') : undefined,
-      builtIn: appRoot ? getAppPathTo(appRoot, 'plugins') : undefined
+      builtIn: appRoot ? getAppPathTo(appRoot, 'plugins') : undefined,
+      bundled: bundledRoot ? getAppPathTo(bundledRoot, 'plugins') : undefined,
     };
   }
 
@@ -91,6 +98,11 @@ export class PluginManager {
       this._entries.push(...await scanDirectory(this._dirs.builtIn, "builtIn"));
     }
 
+    // Load bundled plugins
+    if (this._dirs.bundled) {
+      this._entries.push(...await scanDirectory(this._dirs.bundled, "bundled"));
+    }
+
     if (!process.env.GRIST_EXPERIMENTAL_PLUGINS ||
        process.env.GRIST_EXPERIMENTAL_PLUGINS === '0') {
       // Remove experimental plugins
@@ -130,7 +142,7 @@ export class PluginManager {
 }
 
 
-async function scanDirectory(dir: string, kind: "installed"|"builtIn"): Promise<DirectoryScanEntry[]> {
+async function scanDirectory(dir: string, kind: "installed"|"builtIn"|"bundled"): Promise<DirectoryScanEntry[]> {
   const plugins: DirectoryScanEntry[] = [];
   let listDir;
 

package.json

@@ -114,6 +114,7 @@
     "@googleapis/oauth2": "0.2.0",
     "@gristlabs/connect-sqlite3": "0.9.11-grist.5",
     "@gristlabs/express-session": "1.17.0",
+    "@gristlabs/grist-widget": "^0.0.4",
     "@gristlabs/moment-guess": "1.2.4-grist.1",
     "@gristlabs/pidusage": "2.0.17",
     "@gristlabs/sqlite3": "5.1.4-grist.8",

yarn.lock

@@ -303,6 +303,11 @@
     safe-buffer "5.2.0"
     uid-safe "~2.1.5"
 
+"@gristlabs/grist-widget@^0.0.4":
+  version "0.0.4"
+  resolved "https://registry.yarnpkg.com/@gristlabs/grist-widget/-/grist-widget-0.0.4.tgz#df50d988bcdf8fc26a876cf23b82e258bbdb0ccc"
+  integrity sha512-Q0k+GuudU2+0JkuvVkB9UZzqeUKJH8PsaO9ZfxKuqL9/ssIXUd080msB+PJLXB0TU9BkpzPSl7+kLqXTBSnA5g==
+
 "@gristlabs/moment-guess@1.2.4-grist.1":
   version "1.2.4-grist.1"
   resolved "https://registry.npmjs.org/@gristlabs/moment-guess/-/moment-guess-1.2.4-grist.1.tgz"