pad: Simplify reload after .etherpad import

The old "switch to pad" logic looked buggy, and it complicates pad
initialization. Forcing a refresh after importing an `.etherpad` file
isn't much of a UX downgrade.

CHANGELOG.md

@@ -34,6 +34,7 @@
 
 ### Notable enhancements
 
+* Simplified pad reload after importing an `.etherpad` file.
 * For plugin authors:
   * `clientVars` was added to the context for the `postAceInit` client-side
     hook. Plugins should use this instead of the `clientVars` global variable.

doc/api/hooks_server-side.md

@@ -579,9 +579,9 @@ Things in context:
 This hook allows plugins to grant temporary write access to a pad. It is called
 for each incoming message from a client. If write access is granted, it applies
 to the current message and all future messages from the same socket.io
-connection until the next `CLIENT_READY` or `SWITCH_TO_PAD` message. Read-only
+connection until the next `CLIENT_READY` message. Read-only access is reset
-access is reset **after** each `CLIENT_READY` or `SWITCH_TO_PAD` message, so
+**after** each `CLIENT_READY` message, so granting write access has no effect
-granting write access has no effect for those message types.
+for those message types.
 
 The handleMessageSecurity function must return a Promise. If the Promise
 resolves to `true`, write access is granted as described above. Returning

src/node/handler/ImportHandler.js

@@ -235,8 +235,8 @@ const doImport = async (req, res, padId) => {
   pad = await padManager.getPad(padId);
   padManager.unloadPad(padId);
 
-  // direct Database Access means a pad user should perform a switchToPad
+  // Direct database access means a pad user should reload the pad and not attempt to receive
-  // and not attempt to receive updated pad data
+  // updated pad data.
   if (directDatabaseAccess) return true;
 
   // tell clients to update

src/node/handler/PadMessageHandler.js

@@ -283,8 +283,6 @@ exports.handleMessage = async (socket, message) => {
     } else {
       messageLogger.warn(`Dropped message, unknown COLLABROOM Data  Type ${message.data.type}`);
     }
-  } else if (message.type === 'SWITCH_TO_PAD') {
-    await handleSwitchToPad(socket, message, authorID);
   } else {
     messageLogger.warn(`Dropped message, unknown Message Type ${message.type}`);
   }
@@ -806,44 +804,6 @@ const _correctMarkersInPad = (atext, apool) => {
   return builder.toString();
 };
 
-const handleSwitchToPad = async (socket, message, _authorID) => {
-  const currentSessionInfo = sessioninfos[socket.id];
-  const padId = currentSessionInfo.padId;
-
-  // Check permissions for the new pad.
-  const newPadIds = await readOnlyManager.getIds(message.padId);
-  const {session: {user} = {}} = socket.client.request;
-  const {accessStatus, authorID} = await securityManager.checkAccess(
-      newPadIds.padId, message.sessionID, message.token, user);
-  if (accessStatus !== 'grant') {
-    // Access denied. Send the reason to the user.
-    socket.json.send({accessStatus});
-    return;
-  }
-  // The same token and session ID were passed to checkAccess in handleMessage, so this second call
-  // to checkAccess should return the same author ID.
-  assert(authorID === _authorID);
-  assert(authorID === currentSessionInfo.author);
-
-  // Check if the connection dropped during the access check.
-  if (sessioninfos[socket.id] !== currentSessionInfo) return;
-
-  // clear the session and leave the room
-  _getRoomSockets(padId).forEach((socket) => {
-    const sinfo = sessioninfos[socket.id];
-    if (sinfo && sinfo.author === currentSessionInfo.author) {
-      // fix user's counter, works on page refresh or if user closes browser window and then rejoins
-      sessioninfos[socket.id] = {};
-      socket.leave(padId);
-    }
-  });
-
-  // start up the new pad
-  const newSessionInfo = sessioninfos[socket.id];
-  createSessionInfoAuth(newSessionInfo, message);
-  await handleClientReady(socket, message, authorID);
-};
-
 // Creates/replaces the auth object in the given session info.
 const createSessionInfoAuth = (sessionInfo, message) => {
   // Remember this information since we won't

src/static/js/pad.js

@@ -48,8 +48,6 @@ const socketio = require('./socketio');
 
 const hooks = require('./pluginfw/hooks');
 
-let receivedClientVars = false;
-
 // This array represents all GET-parameters which can be used to change a setting.
 //   name:     the parameter-name, eg  `?noColors=true`  =>  `noColors`
 //   checkVal: the callback is only executed when
@@ -181,8 +179,7 @@ const getUrlVars = () => {
   return vars;
 };
 
-const sendClientReady = (isReconnect, messageType) => {
+const sendClientReady = (isReconnect) => {
-  messageType = typeof messageType !== 'undefined' ? messageType : 'CLIENT_READY';
   let padId = document.location.pathname.substring(document.location.pathname.lastIndexOf('/') + 1);
   // unescape neccesary due to Safari and Opera interpretation of spaces
   padId = decodeURIComponent(padId);
@@ -201,7 +198,7 @@ const sendClientReady = (isReconnect, messageType) => {
 
   const msg = {
     component: 'pad',
-    type: messageType,
+    type: 'CLIENT_READY',
     padId,
     sessionID: Cookies.get('sessionID'),
     token,
@@ -218,6 +215,7 @@ const sendClientReady = (isReconnect, messageType) => {
 };
 
 const handshake = () => {
+  let receivedClientVars = false;
   let padId = document.location.pathname.substring(document.location.pathname.lastIndexOf('/') + 1);
   // unescape neccesary due to Safari and Opera interpretation of spaces
   padId = decodeURIComponent(padId);
@@ -394,38 +392,6 @@ const pad = {
   getUserId: () => pad.myUserInfo.userId,
   getUserName: () => pad.myUserInfo.name,
   userList: () => paduserlist.users(),
-  switchToPad: (padId) => {
-    let newHref = new RegExp(/.*\/p\/[^/]+/).exec(document.location.pathname) || clientVars.padId;
-    newHref = newHref[0];
-
-    const options = clientVars.padOptions;
-    if (typeof options !== 'undefined' && options != null) {
-      const optionArr = [];
-      $.each(options, (k, v) => {
-        const str = `${k}=${v}`;
-        optionArr.push(str);
-      });
-      const optionStr = optionArr.join('&');
-
-      newHref = `${newHref}?${optionStr}`;
-    }
-
-    // destroy old pad from DOM
-    // See https://github.com/ether/etherpad-lite/pull/3915
-    // TODO: Check if Destroying is enough and doesn't leave negative stuff
-    // See ace.js "editor.destroy" for a reference of how it was done before
-    $('#editorcontainer').find('iframe')[0].remove();
-
-    if (window.history && window.history.pushState) {
-      $('#chattext p').remove(); // clear the chat messages
-      window.history.pushState('', '', newHref);
-      receivedClientVars = false;
-      sendClientReady(false, 'SWITCH_TO_PAD');
-    } else {
-      // fallback
-      window.location.href = newHref;
-    }
-  },
   sendClientMessage: (msg) => {
     pad.collabClient.sendClientMessage(msg);
   },

src/static/js/pad_impexp.js

@@ -67,7 +67,7 @@ const padimpexp = (() => {
         importErrorMessage(message);
       } else {
         $('#import_export').removeClass('popup-show');
-        if (directDatabaseAccess) pad.switchToPad(clientVars.padId);
+        if (directDatabaseAccess) window.location.reload();
       }
       $('#importsubmitinput').removeAttr('disabled').val(html10n.get('pad.impexp.importbutton'));
       window.setTimeout(() => $('#importfileinput').removeAttr('disabled'), 0);