mirror of
https://github.com/Jermolene/TiddlyWiki5
synced 2024-11-27 12:07:19 +00:00
a01bbd4b9c
We re-use some of the existing syncer mechanism. It was already keeping track of changes to tiddlers in the store when working with a tiddler syncadaptor. Now it also tracks changes when there is no syncadaptor, allowing us to provide a warning if there are unsaved changes.
566 lines
16 KiB
JavaScript
566 lines
16 KiB
JavaScript
/*\
|
|
title: $:/core/modules/syncer.js
|
|
type: application/javascript
|
|
module-type: global
|
|
|
|
The syncer tracks changes to the store. If a syncadaptor is used then individual tiddlers are synchronised through it. If there is no syncadaptor then the entire wiki is saved via saver modules.
|
|
|
|
\*/
|
|
(function(){
|
|
|
|
/*jslint node: true, browser: true */
|
|
/*global $tw: false */
|
|
"use strict";
|
|
|
|
/*
|
|
Instantiate the syncer with the following options:
|
|
wiki: wiki to be synced
|
|
*/
|
|
function Syncer(options) {
|
|
var self = this;
|
|
this.wiki = options.wiki;
|
|
// Make a logger
|
|
this.log = $tw.logger.makeLog("syncer");
|
|
// Find a working syncadaptor
|
|
this.syncadaptor = undefined;
|
|
$tw.modules.forEachModuleOfType("syncadaptor",function(title,module) {
|
|
if(!self.syncadaptor && module.adaptorClass) {
|
|
self.syncadaptor = new module.adaptorClass(self);
|
|
}
|
|
});
|
|
// Initialise our savers
|
|
if($tw.browser) {
|
|
this.initSavers();
|
|
}
|
|
// Compile the dirty tiddler filter
|
|
this.filterFn = this.wiki.compileFilter(this.wiki.getTiddlerText(this.titleSyncFilter));
|
|
// Record information for known tiddlers
|
|
this.readTiddlerInfo();
|
|
// Tasks are {type: "load"/"save"/"delete", title:, queueTime:, lastModificationTime:}
|
|
this.taskQueue = {}; // Hashmap of tasks yet to be performed
|
|
this.taskInProgress = {}; // Hash of tasks in progress
|
|
this.taskTimerId = null; // Timer for task dispatch
|
|
this.pollTimerId = null; // Timer for polling server
|
|
// Listen out for changes to tiddlers
|
|
this.wiki.addEventListener("change",function(changes) {
|
|
self.syncToServer(changes);
|
|
});
|
|
// Listen out for lazyLoad events
|
|
if(this.syncadaptor) {
|
|
this.wiki.addEventListener("lazyLoad",function(title) {
|
|
self.handleLazyLoadEvent(title);
|
|
});
|
|
}
|
|
// Listen out for login/logout/refresh events in the browser
|
|
if($tw.browser) {
|
|
document.addEventListener("tw-login",function(event) {
|
|
self.handleLoginEvent(event);
|
|
},false);
|
|
document.addEventListener("tw-logout",function(event) {
|
|
self.handleLogoutEvent(event);
|
|
},false);
|
|
document.addEventListener("tw-server-refresh",function(event) {
|
|
self.handleRefreshEvent(event);
|
|
},false);
|
|
}
|
|
// Get the login status
|
|
this.getStatus(function (err,isLoggedIn) {
|
|
if(isLoggedIn) {
|
|
// Do a sync from the server
|
|
self.syncFromServer();
|
|
}
|
|
});
|
|
}
|
|
|
|
/*
|
|
Error handling
|
|
*/
|
|
Syncer.prototype.showError = function(error) {
|
|
this.log("Error: " + error);
|
|
};
|
|
|
|
/*
|
|
Constants
|
|
*/
|
|
Syncer.prototype.titleIsLoggedIn = "$:/status/IsLoggedIn";
|
|
Syncer.prototype.titleUserName = "$:/status/UserName";
|
|
Syncer.prototype.titleSyncFilter = "$:/config/SyncFilter";
|
|
Syncer.prototype.titleAutoSave = "$:/config/AutoSave";
|
|
Syncer.prototype.taskTimerInterval = 1 * 1000; // Interval for sync timer
|
|
Syncer.prototype.throttleInterval = 1 * 1000; // Defer saving tiddlers if they've changed in the last 1s...
|
|
Syncer.prototype.fallbackInterval = 10 * 1000; // Unless the task is older than 10s
|
|
Syncer.prototype.pollTimerInterval = 60 * 1000; // Interval for polling for changes from the adaptor
|
|
|
|
/*
|
|
Read (or re-read) the latest tiddler info from the store
|
|
*/
|
|
Syncer.prototype.readTiddlerInfo = function() {
|
|
// Hashmap by title of {revision:,changeCount:,adaptorInfo:}
|
|
this.tiddlerInfo = {};
|
|
// Record information for known tiddlers
|
|
var self = this;
|
|
this.wiki.forEachTiddler({includeSystem: true},function(title,tiddler) {
|
|
self.tiddlerInfo[title] = {
|
|
revision: tiddler.fields["revision"],
|
|
adaptorInfo: self.syncadaptor && self.syncadaptor.getTiddlerInfo(tiddler),
|
|
changeCount: self.wiki.getChangeCount(title)
|
|
}
|
|
});
|
|
};
|
|
|
|
/*
|
|
Select the appropriate saver modules and set them up
|
|
*/
|
|
Syncer.prototype.initSavers = function(moduleType) {
|
|
moduleType = moduleType || "saver";
|
|
// Instantiate the available savers
|
|
this.savers = [];
|
|
var self = this;
|
|
$tw.modules.forEachModuleOfType(moduleType,function(title,module) {
|
|
if(module.canSave(self)) {
|
|
self.savers.push(module.create(self.wiki));
|
|
}
|
|
});
|
|
// Sort the savers into priority order
|
|
this.savers.sort(function(a,b) {
|
|
if(a.info.priority < b.info.priority) {
|
|
return -1;
|
|
} else {
|
|
if(a.info.priority > b.info.priority) {
|
|
return +1;
|
|
} else {
|
|
return 0;
|
|
}
|
|
}
|
|
});
|
|
};
|
|
|
|
/*
|
|
Save the wiki contents. Options are:
|
|
method: "save" or "download"
|
|
template: the tiddler containing the template to save
|
|
downloadType: the content type for the saved file
|
|
*/
|
|
Syncer.prototype.saveWiki = function(options) {
|
|
options = options || {};
|
|
var method = options.method || "save",
|
|
template = options.template || "$:/core/save/all",
|
|
downloadType = options.downloadType || "text/plain",
|
|
text = this.wiki.renderTiddler(downloadType,template),
|
|
callback = function(err) {
|
|
if(err) {
|
|
alert("Error while saving:\n\n" + err);
|
|
} else {
|
|
$tw.notifier.display("$:/messages/Saved");
|
|
if(options.callback) {
|
|
options.callback();
|
|
}
|
|
}
|
|
};
|
|
// Ignore autosave if we've got a syncadaptor or autosave is disabled
|
|
if(method === "autosave") {
|
|
if(this.syncadaptor || this.wiki.getTiddlerText(this.titleAutoSave,"yes") !== "yes") {
|
|
return false;
|
|
}
|
|
}
|
|
// Call the highest priority saver that supports this method
|
|
for(var t=this.savers.length-1; t>=0; t--) {
|
|
var saver = this.savers[t];
|
|
if(saver.info.capabilities.indexOf(method) !== -1 && saver.save(text,method,callback)) {
|
|
this.log("Saving wiki with method",method,"through saver",saver.info.name);
|
|
// Clear the task queue if we're saving (rather than downloading)
|
|
if(method !== "download") {
|
|
this.readTiddlerInfo();
|
|
this.taskQueue = {};
|
|
}
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
};
|
|
|
|
/*
|
|
Checks whether the wiki is dirty (ie the window shouldn't be closed)
|
|
*/
|
|
Syncer.prototype.isDirty = function() {
|
|
return (this.numTasksInQueue() > 0) || (this.numTasksInProgress() > 0);
|
|
};
|
|
|
|
/*
|
|
Save an incoming tiddler in the store, and updates the associated tiddlerInfo
|
|
*/
|
|
Syncer.prototype.storeTiddler = function(tiddlerFields) {
|
|
// Save the tiddler
|
|
var tiddler = new $tw.Tiddler(this.wiki.getTiddler(tiddlerFields.title),tiddlerFields);
|
|
this.wiki.addTiddler(tiddler);
|
|
// Save the tiddler revision and changeCount details
|
|
this.tiddlerInfo[tiddlerFields.title] = {
|
|
revision: tiddlerFields.revision,
|
|
adaptorInfo: this.syncadaptor.getTiddlerInfo(tiddler),
|
|
changeCount: this.wiki.getChangeCount(tiddlerFields.title)
|
|
};
|
|
};
|
|
|
|
Syncer.prototype.getStatus = function(callback) {
|
|
var self = this;
|
|
// Check if the adaptor supports getStatus()
|
|
if(this.syncadaptor && this.syncadaptor.getStatus) {
|
|
// Mark us as not logged in
|
|
this.wiki.addTiddler({title: this.titleIsLoggedIn,text: "no"});
|
|
// Get login status
|
|
this.syncadaptor.getStatus(function(err,isLoggedIn,username) {
|
|
if(err) {
|
|
self.showError(err);
|
|
return;
|
|
}
|
|
// Set the various status tiddlers
|
|
self.wiki.addTiddler({title: self.titleIsLoggedIn,text: isLoggedIn ? "yes" : "no"});
|
|
if(isLoggedIn) {
|
|
self.wiki.addTiddler({title: self.titleUserName,text: username || ""});
|
|
} else {
|
|
self.wiki.deleteTiddler(self.titleUserName);
|
|
}
|
|
// Invoke the callback
|
|
if(callback) {
|
|
callback(err,isLoggedIn,username);
|
|
}
|
|
});
|
|
} else {
|
|
callback(null,true,"UNAUTHENTICATED");
|
|
}
|
|
};
|
|
|
|
/*
|
|
Synchronise from the server by reading the skinny tiddler list and queuing up loads for any tiddlers that we don't already have up to date
|
|
*/
|
|
Syncer.prototype.syncFromServer = function() {
|
|
if(this.syncadaptor && this.syncadaptor.getSkinnyTiddlers) {
|
|
this.log("Retrieving skinny tiddler list");
|
|
var self = this;
|
|
if(this.pollTimerId) {
|
|
clearTimeout(this.pollTimerId);
|
|
this.pollTimerId = null;
|
|
}
|
|
this.syncadaptor.getSkinnyTiddlers(function(err,tiddlers) {
|
|
// Trigger another sync
|
|
self.pollTimerId = setTimeout(function() {
|
|
self.pollTimerId = null;
|
|
self.syncFromServer.call(self);
|
|
},self.pollTimerInterval);
|
|
// Check for errors
|
|
if(err) {
|
|
self.log("Error retrieving skinny tiddler list:",err);
|
|
return;
|
|
}
|
|
// Process each incoming tiddler
|
|
for(var t=0; t<tiddlers.length; t++) {
|
|
// Get the incoming tiddler fields, and the existing tiddler
|
|
var tiddlerFields = tiddlers[t],
|
|
incomingRevision = tiddlerFields.revision + "",
|
|
tiddler = self.wiki.getTiddler(tiddlerFields.title),
|
|
tiddlerInfo = self.tiddlerInfo[tiddlerFields.title],
|
|
currRevision = tiddlerInfo ? tiddlerInfo.revision : null;
|
|
// Ignore the incoming tiddler if it's the same as the revision we've already got
|
|
if(currRevision !== incomingRevision) {
|
|
// Do a full load if we've already got a fat version of the tiddler
|
|
if(tiddler && tiddler.fields.text !== undefined) {
|
|
// Do a full load of this tiddler
|
|
self.enqueueSyncTask({
|
|
type: "load",
|
|
title: tiddlerFields.title
|
|
});
|
|
} else {
|
|
// Load the skinny version of the tiddler
|
|
self.storeTiddler(tiddlerFields);
|
|
}
|
|
}
|
|
}
|
|
});
|
|
}
|
|
};
|
|
|
|
/*
|
|
Synchronise a set of changes to the server
|
|
*/
|
|
Syncer.prototype.syncToServer = function(changes) {
|
|
var self = this,
|
|
now = new Date(),
|
|
filteredChanges = this.filterFn.call(this.wiki,changes);
|
|
$tw.utils.each(changes,function(change,title,object) {
|
|
// Ignore the change if it is a shadow tiddler
|
|
if((change.deleted && $tw.utils.hop(self.tiddlerInfo,title)) || (!change.deleted && filteredChanges.indexOf(title) !== -1)) {
|
|
// Queue a task to sync this tiddler
|
|
self.enqueueSyncTask({
|
|
type: change.deleted ? "delete" : "save",
|
|
title: title
|
|
});
|
|
}
|
|
});
|
|
};
|
|
|
|
/*
|
|
Lazily load a skinny tiddler if we can
|
|
*/
|
|
Syncer.prototype.handleLazyLoadEvent = function(title) {
|
|
console.log("Lazy loading",title)
|
|
// Queue up a sync task to load this tiddler
|
|
this.enqueueSyncTask({
|
|
type: "load",
|
|
title: title
|
|
});
|
|
};
|
|
|
|
/*
|
|
Dispay a password prompt and allow the user to login
|
|
*/
|
|
Syncer.prototype.handleLoginEvent = function() {
|
|
var self = this;
|
|
this.getStatus(function(err,isLoggedIn,username) {
|
|
if(!isLoggedIn) {
|
|
$tw.passwordPrompt.createPrompt({
|
|
serviceName: "Login to TiddlySpace",
|
|
callback: function(data) {
|
|
self.login(data.username,data.password,function(err,isLoggedIn) {
|
|
self.syncFromServer();
|
|
});
|
|
return true; // Get rid of the password prompt
|
|
}
|
|
});
|
|
}
|
|
});
|
|
};
|
|
|
|
/*
|
|
Attempt to login to TiddlyWeb.
|
|
username: username
|
|
password: password
|
|
callback: invoked with arguments (err,isLoggedIn)
|
|
*/
|
|
Syncer.prototype.login = function(username,password,callback) {
|
|
this.log("Attempting to login as",username);
|
|
var self = this;
|
|
if(this.syncadaptor.login) {
|
|
this.syncadaptor.login(username,password,function(err) {
|
|
if(err) {
|
|
return callback(err);
|
|
}
|
|
self.getStatus(function(err,isLoggedIn,username) {
|
|
if(callback) {
|
|
callback(null,isLoggedIn);
|
|
}
|
|
});
|
|
});
|
|
} else {
|
|
callback(null,true);
|
|
}
|
|
};
|
|
|
|
/*
|
|
Attempt to log out of TiddlyWeb
|
|
*/
|
|
Syncer.prototype.handleLogoutEvent = function() {
|
|
this.log("Attempting to logout");
|
|
var self = this;
|
|
if(this.syncadaptor.logout) {
|
|
this.syncadaptor.logout(function(err) {
|
|
if(err) {
|
|
self.showError(err);
|
|
} else {
|
|
self.getStatus();
|
|
}
|
|
});
|
|
}
|
|
};
|
|
|
|
/*
|
|
Immediately refresh from the server
|
|
*/
|
|
Syncer.prototype.handleRefreshEvent = function() {
|
|
this.syncFromServer();
|
|
};
|
|
|
|
/*
|
|
Queue up a sync task. If there is already a pending task for the tiddler, just update the last modification time
|
|
*/
|
|
Syncer.prototype.enqueueSyncTask = function(task) {
|
|
var self = this,
|
|
now = new Date();
|
|
// Set the timestamps on this task
|
|
task.queueTime = now;
|
|
task.lastModificationTime = now;
|
|
// Fill in some tiddlerInfo if the tiddler is one we haven't seen before
|
|
if(!$tw.utils.hop(this.tiddlerInfo,task.title)) {
|
|
this.tiddlerInfo[task.title] = {
|
|
revision: null,
|
|
adaptorInfo: {},
|
|
changeCount: -1
|
|
}
|
|
}
|
|
// Bail if this is a save and the tiddler is already at the changeCount that the server has
|
|
if(task.type === "save" && this.wiki.getChangeCount(task.title) <= this.tiddlerInfo[task.title].changeCount) {
|
|
return;
|
|
}
|
|
// Check if this tiddler is already in the queue
|
|
if($tw.utils.hop(this.taskQueue,task.title)) {
|
|
// this.log("Re-queueing up sync task with type:",task.type,"title:",task.title);
|
|
var existingTask = this.taskQueue[task.title];
|
|
// If so, just update the last modification time
|
|
existingTask.lastModificationTime = task.lastModificationTime;
|
|
// If the new task is a save then we upgrade the existing task to a save. Thus a pending load is turned into a save if the tiddler changes locally in the meantime. But a pending save is not modified to become a load
|
|
if(task.type === "save" || task.type === "delete") {
|
|
existingTask.type = task.type;
|
|
}
|
|
} else {
|
|
// this.log("Queuing up sync task with type:",task.type,"title:",task.title);
|
|
// If it is not in the queue, insert it
|
|
this.taskQueue[task.title] = task;
|
|
}
|
|
// Process the queue
|
|
if(this.syncadaptor) {
|
|
$tw.utils.nextTick(function() {self.processTaskQueue.call(self);});
|
|
}
|
|
};
|
|
|
|
/*
|
|
Return the number of tasks in progress
|
|
*/
|
|
Syncer.prototype.numTasksInProgress = function() {
|
|
return $tw.utils.count(this.taskInProgress);
|
|
};
|
|
|
|
/*
|
|
Return the number of tasks in the queue
|
|
*/
|
|
Syncer.prototype.numTasksInQueue = function() {
|
|
return $tw.utils.count(this.taskQueue);
|
|
};
|
|
|
|
/*
|
|
Trigger a timeout if one isn't already outstanding
|
|
*/
|
|
Syncer.prototype.triggerTimeout = function() {
|
|
var self = this;
|
|
if(!this.taskTimerId) {
|
|
this.taskTimerId = setTimeout(function() {
|
|
self.taskTimerId = null;
|
|
self.processTaskQueue.call(self);
|
|
},self.taskTimerInterval);
|
|
}
|
|
};
|
|
|
|
/*
|
|
Process the task queue, performing the next task if appropriate
|
|
*/
|
|
Syncer.prototype.processTaskQueue = function() {
|
|
var self = this;
|
|
// Only process a task if we're not already performing a task. If we are already performing a task then we'll dispatch the next one when it completes
|
|
if(this.numTasksInProgress() === 0) {
|
|
// Choose the next task to perform
|
|
var task = this.chooseNextTask();
|
|
// Perform the task if we had one
|
|
if(task) {
|
|
// Remove the task from the queue and add it to the in progress list
|
|
delete this.taskQueue[task.title];
|
|
this.taskInProgress[task.title] = task;
|
|
// Dispatch the task
|
|
this.dispatchTask(task,function(err) {
|
|
if(err) {
|
|
self.showError("Sync error while processing '" + task.title + "':\n" + err);
|
|
}
|
|
// Mark that this task is no longer in progress
|
|
delete self.taskInProgress[task.title];
|
|
// Process the next task
|
|
self.processTaskQueue.call(self);
|
|
});
|
|
} else {
|
|
// Make sure we've set a time if there wasn't a task to perform, but we've still got tasks in the queue
|
|
if(this.numTasksInQueue() > 0) {
|
|
this.triggerTimeout();
|
|
}
|
|
}
|
|
}
|
|
};
|
|
|
|
/*
|
|
Choose the next applicable task
|
|
*/
|
|
Syncer.prototype.chooseNextTask = function() {
|
|
var self = this,
|
|
candidateTask = null,
|
|
now = new Date();
|
|
// Select the best candidate task
|
|
$tw.utils.each(this.taskQueue,function(task,title) {
|
|
// Exclude the task if there's one of the same name in progress
|
|
if($tw.utils.hop(self.taskInProgress,title)) {
|
|
return;
|
|
}
|
|
// Exclude the task if it is a save and the tiddler has been modified recently, but not hit the fallback time
|
|
if(task.type === "save" && (now - task.lastModificationTime) < self.throttleInterval &&
|
|
(now - task.queueTime) < self.fallbackInterval) {
|
|
return;
|
|
}
|
|
// Exclude the task if it is newer than the current best candidate
|
|
if(candidateTask && candidateTask.queueTime < task.queueTime) {
|
|
return;
|
|
}
|
|
// Now this is our best candidate
|
|
candidateTask = task;
|
|
});
|
|
return candidateTask;
|
|
};
|
|
|
|
/*
|
|
Dispatch a task and invoke the callback
|
|
*/
|
|
Syncer.prototype.dispatchTask = function(task,callback) {
|
|
var self = this;
|
|
if(task.type === "save") {
|
|
var changeCount = this.wiki.getChangeCount(task.title),
|
|
tiddler = this.wiki.getTiddler(task.title);
|
|
this.log("Dispatching 'save' task:",task.title);
|
|
if(tiddler) {
|
|
this.syncadaptor.saveTiddler(tiddler,function(err,adaptorInfo,revision) {
|
|
if(err) {
|
|
return callback(err);
|
|
}
|
|
// Adjust the info stored about this tiddler
|
|
self.tiddlerInfo[task.title] = {
|
|
changeCount: changeCount,
|
|
adaptorInfo: adaptorInfo,
|
|
revision: revision
|
|
};
|
|
// Invoke the callback
|
|
callback(null);
|
|
});
|
|
}
|
|
} else if(task.type === "load") {
|
|
// Load the tiddler
|
|
this.log("Dispatching 'load' task:",task.title);
|
|
this.syncadaptor.loadTiddler(task.title,function(err,tiddlerFields) {
|
|
if(err) {
|
|
return callback(err);
|
|
}
|
|
// Store the tiddler
|
|
if(tiddlerFields) {
|
|
self.storeTiddler(tiddlerFields);
|
|
}
|
|
// Invoke the callback
|
|
callback(null);
|
|
});
|
|
} else if(task.type === "delete") {
|
|
// Delete the tiddler
|
|
this.log("Dispatching 'delete' task:",task.title);
|
|
this.syncadaptor.deleteTiddler(task.title,function(err) {
|
|
if(err) {
|
|
return callback(err);
|
|
}
|
|
// Invoke the callback
|
|
callback(null);
|
|
});
|
|
}
|
|
};
|
|
|
|
exports.Syncer = Syncer;
|
|
|
|
})();
|