Simplify read-only pad ID checks

src/node/db/ReadOnlyManager.js

@@ -28,7 +28,7 @@ const randomString = require('../utils/randomstring');
  * checks if the id pattern matches a read-only pad id
  * @param {String} the pad's id
  */
-exports.isReadOnlyId = (id) => id.indexOf('r.') === 0;
+exports.isReadOnlyId = (id) => id.startsWith('r.');
 
 /**
  * returns a read only id for a pad
@@ -59,7 +59,7 @@ exports.getPadId = (readOnlyId) => db.get(`readonly2pad:${readOnlyId}`);
  * @param {String} padIdOrReadonlyPadId read only id or real pad id
  */
 exports.getIds = async (id) => {
-  const readonly = (id.indexOf('r.') === 0);
+  const readonly = exports.isReadOnlyId(id);
 
   // Might be null, if this is an unknown read-only id
   const readOnlyPadId = readonly ? id : await exports.getReadOnlyId(id);

src/node/hooks/express/specialpages.js

@@ -46,8 +46,7 @@ exports.expressCreateServer = (hookName, args, cb) => {
   // serve pad.html under /p
   args.app.get('/p/:pad', (req, res, next) => {
     // The below might break for pads being rewritten
-    const isReadOnly =
-        req.url.indexOf('/p/r.') === 0 || !webaccess.userCanModify(req.params.pad, req);
+    const isReadOnly = !webaccess.userCanModify(req.params.pad, req);
 
     hooks.callAll('padInitToolbar', {
       toolbar,