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mirror of https://github.com/Jermolene/TiddlyWiki5 synced 2024-11-23 18:17:20 +00:00
TiddlyWiki5/plugins/tiddlywiki/tiddlyweb/tiddlyweb.js
2013-01-28 19:27:22 +00:00

601 lines
18 KiB
JavaScript

/*\
title: $:/plugins/tiddlywiki/tiddlyweb/tiddlyweb.js
type: application/javascript
module-type: syncer
Main TiddlyWeb syncer module
\*/
(function(){
/*jslint node: true, browser: true */
/*global $tw: false */
"use strict";
/*
Creates a TiddlyWebSyncer object
*/
var TiddlyWebSyncer = function(options) {
this.wiki = options.wiki;
this.connection = undefined;
this.tiddlerInfo = {}; // Hashmap of {revision:,changeCount:}
// Tasks are {type: "load"/"save", title:, queueTime:, lastModificationTime:}
this.taskQueue = {}; // Hashmap of tasks to be performed
this.taskInProgress = {}; // Hash of tasks in progress
this.taskTimerId = null; // Sync timer
};
TiddlyWebSyncer.titleIsLoggedIn = "$:/plugins/tiddlyweb/IsLoggedIn";
TiddlyWebSyncer.titleUserName = "$:/plugins/tiddlyweb/UserName";
TiddlyWebSyncer.taskTimerInterval = 1 * 1000; // Interval for sync timer
TiddlyWebSyncer.throttleInterval = 1 * 1000; // Defer saving tiddlers if they've changed in the last 1s...
TiddlyWebSyncer.fallbackInterval = 10 * 1000; // Unless the task is older than 10s
TiddlyWebSyncer.pollTimerInterval = 60 * 1000; // Interval for polling for changes on the server
/*
Error handling
*/
TiddlyWebSyncer.prototype.showError = function(error) {
alert("TiddlyWeb error: " + error);
console.log("TiddlyWeb error: " + error);
};
/*
Message logging
*/
TiddlyWebSyncer.prototype.log = function(/* arguments */) {
var args = Array.prototype.slice.call(arguments,0);
args[0] = "TiddlyWeb: " + args[0];
$tw.utils.log.apply(null,args);
};
TiddlyWebSyncer.prototype.addConnection = function(connection) {
var self = this;
// Check if we've already got a connection
if(this.connection) {
return new Error("TiddlyWebSyncer can only handle a single connection");
}
// If we don't have a host then substitute the host of the page
if(!connection.host) {
connection.host = document.location.protocol + "//" + document.location.host + "/";
}
// Mark us as not logged in
this.wiki.addTiddler({title: TiddlyWebSyncer.titleIsLoggedIn,text: "no"});
// Save the connection object
this.connection = connection;
// Listen out for changes to tiddlers
this.wiki.addEventListener("",function(changes) {
self.syncToServer(changes);
});
this.log("Adding connection with recipe:",connection.recipe,"host:",connection.host);
// Get the login status
this.getStatus(function (err,isLoggedIn,json) {
if(isLoggedIn) {
// Do a sync
self.syncFromServer();
}
});
return ""; // We only support a single connection
};
/*
Handle syncer messages
*/
TiddlyWebSyncer.prototype.handleEvent = function(event) {
switch(event.type) {
case "tw-login":
this.promptLogin();
break;
case "tw-logout":
this.logout();
break;
}
};
/*
Lazily load a skinny tiddler if we can
*/
TiddlyWebSyncer.prototype.lazyLoad = function(connection,title,tiddler) {
// Queue up a sync task to load this tiddler
this.enqueueSyncTask({
type: "load",
title: title
});
};
/*
Get the current status of the TiddlyWeb connection
*/
TiddlyWebSyncer.prototype.getStatus = function(callback) {
// Get status
var self = this;
this.log("Getting status");
this.httpRequest({
url: this.connection.host + "status",
callback: function(err,data) {
if(err) {
return callback(err);
}
// Decode the status JSON
var json = null,
isLoggedIn = false;
try {
json = JSON.parse(data);
} catch (e) {
}
if(json) {
// Use the recipe if we don't already have one
if(!self.connection.recipe) {
self.connection.recipe = json.space.recipe;
}
// Check if we're logged in
isLoggedIn = json.username !== "GUEST";
// Set the various status tiddlers
self.wiki.addTiddler({title: TiddlyWebSyncer.titleIsLoggedIn,text: isLoggedIn ? "yes" : "no"});
if(isLoggedIn) {
self.wiki.addTiddler({title: TiddlyWebSyncer.titleUserName,text: json.username});
} else {
self.wiki.deleteTiddler(TiddlyWebSyncer.titleUserName);
}
}
// Invoke the callback if present
if(callback) {
callback(null,isLoggedIn,json);
}
}
});
};
/*
Dispay a password prompt and allow the user to login
*/
TiddlyWebSyncer.prototype.promptLogin = function() {
var self = this;
this.getStatus(function(isLoggedIn,json) {
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)
*/
TiddlyWebSyncer.prototype.login = function(username,password,callback) {
this.log("Attempting to login as",username);
var self = this,
httpRequest = this.httpRequest({
url: this.connection.host + "challenge/tiddlywebplugins.tiddlyspace.cookie_form",
type: "POST",
data: {
user: username,
password: password,
tiddlyweb_redirect: "/status" // workaround to marginalize automatic subsequent GET
},
callback: function(err,data) {
if(err) {
if(callback) {
callback(err);
}
} else {
self.log("Returned from logging in with data:",data);
self.getStatus(function(err,isLoggedIn,json) {
if(callback) {
callback(null,isLoggedIn);
}
});
}
}
});
};
/*
Attempt to log out of TiddlyWeb
*/
TiddlyWebSyncer.prototype.logout = function(options) {
options = options || {};
this.log("Attempting to logout");
var self = this,
httpRequest = this.httpRequest({
url: this.connection.host + "logout",
type: "POST",
data: {
csrf_token: this.getCsrfToken(),
tiddlyweb_redirect: "/status" // workaround to marginalize automatic subsequent GET
},
callback: function(err,data) {
if(err) {
self.showError("logout error: " + err);
} else {
self.log("Returned from logging out with data:",data);
self.getStatus();
}
}
});
};
/*
Synchronise from the server by reading the tiddler list from the recipe and queuing up GETs for any tiddlers that we don't already have
*/
TiddlyWebSyncer.prototype.syncFromServer = function() {
this.log("Retrieving skinny tiddler list");
var self = this;
this.httpRequest({
url: this.connection.host + "recipes/" + this.connection.recipe + "/tiddlers.json",
callback: function(err,data) {
// Check for errors
if(err) {
self.log("Error retrieving skinny tiddler list:",err);
return;
}
// Process each incoming tiddler
var json = JSON.parse(data);
for(var t=0; t<json.length; t++) {
// Get the incoming tiddler fields, and the existing tiddler
var tiddlerFields = json[t],
incomingRevision = tiddlerFields.revision.toString(),
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,incomingRevision);
}
}
}
// Trigger another sync
window.setTimeout(function() {
self.syncFromServer.call(self);
},TiddlyWebSyncer.pollTimerInterval);
}
});
};
/*
Synchronise a set of changes to the server
*/
TiddlyWebSyncer.prototype.syncToServer = function(changes) {
var self = this,
now = new Date();
$tw.utils.each(changes,function(element,title,object) {
// Queue a task to sync this tiddler
self.enqueueSyncTask({
type: "save",
title: title
});
});
};
/*
Queue up a sync task. If there is already a pending task for the tiddler, just update the last modification time
*/
TiddlyWebSyncer.prototype.enqueueSyncTask = function(task) {
var self = this,
now = new Date();
// Set the timestamps on this task
task.queueTime = now;
task.lastModificationTime = now;
// Bail if it's not a tiddler we know about
if(!$tw.utils.hop(this.tiddlerInfo,task.title)) {
return;
}
// 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 GET is turned into a PUT if the tiddler changes locally in the meantime. But a pending save is not modified to become a GET
if(task.type === "save") {
existingTask.type = "save";
}
} 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
$tw.utils.nextTick(function() {self.processTaskQueue.call(self);});
};
/*
Return the number of tasks in progress
*/
TiddlyWebSyncer.prototype.numTasksInProgress = function() {
return $tw.utils.count(this.taskInProgress);
};
/*
Return the number of tasks in the queue
*/
TiddlyWebSyncer.prototype.numTasksInQueue = function() {
return $tw.utils.count(this.taskQueue);
};
/*
Trigger a timeout if one isn't already outstanding
*/
TiddlyWebSyncer.prototype.triggerTimeout = function() {
var self = this;
if(!this.taskTimerId) {
this.taskTimerId = window.setTimeout(function() {
self.taskTimerId = null;
self.processTaskQueue.call(self);
},TiddlyWebSyncer.taskTimerInterval);
}
};
/*
Process the task queue, performing the next task if appropriate
*/
TiddlyWebSyncer.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) {
// 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
*/
TiddlyWebSyncer.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) < TiddlyWebSyncer.throttleInterval &&
(now - task.queueTime) < TiddlyWebSyncer.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
*/
TiddlyWebSyncer.prototype.dispatchTask = function(task,callback) {
var self = this;
if(task.type === "save") {
var changeCount = this.wiki.getChangeCount(task.title);
this.log("Dispatching 'save' task:",task.title);
this.httpRequest({
url: this.connection.host + "recipes/" + this.connection.recipe + "/tiddlers/" + task.title,
type: "PUT",
headers: {
"Content-type": "application/json"
},
data: this.convertTiddlerToTiddlyWebFormat(task.title),
callback: function(err,data,request) {
if(err) {
return callback(err);
}
// Save the details of the new revision of the tiddler
var tiddlerInfo = self.tiddlerInfo[task.title];
tiddlerInfo.changeCount = changeCount;
tiddlerInfo.revision = self.getRevisionFromEtag(request);
// Invoke the callback
callback(null);
}
});
} else if(task.type === "load") {
// Load the tiddler
this.log("Dispatching 'load' task:",task.title);
this.httpRequest({
url: this.connection.host + "recipes/" + this.connection.recipe + "/tiddlers/" + task.title,
callback: function(err,data,request) {
if(err) {
return callback(err);
}
// Store the tiddler and revision number
self.storeTiddler(JSON.parse(data),self.getRevisionFromEtag(request));
// Invoke the callback
callback(null);
}
});
}
};
/*
Convert a TiddlyWeb JSON tiddler into a TiddlyWiki5 tiddler and save it in the store. Returns true if the tiddler was actually stored
*/
TiddlyWebSyncer.prototype.storeTiddler = function(tiddlerFields,revision) {
var self = this,
result = {};
// Transfer the fields, pulling down the `fields` hashmap
$tw.utils.each(tiddlerFields,function(element,title,object) {
if(title === "fields") {
$tw.utils.each(element,function(element,subTitle,object) {
result[subTitle] = element;
});
} else {
result[title] = tiddlerFields[title];
}
});
// Some unholy freaking of content types
if(result.type === "text/javascript") {
result.type = "application/javascript";
} else if(!result.type || result.type === "None") {
result.type = "text/x-tiddlywiki";
}
// Save the tiddler
self.wiki.addTiddler(new $tw.Tiddler(self.wiki.getTiddler(result.title),result));
// Save the tiddler revision and changeCount details
self.tiddlerInfo[result.title] = {
revision: revision,
changeCount: self.wiki.getChangeCount(result.title)
};
};
/*
Convert a tiddler to a field set suitable for PUTting to TiddlyWeb
*/
TiddlyWebSyncer.prototype.convertTiddlerToTiddlyWebFormat = function(title) {
var result = {},
tiddler = this.wiki.getTiddler(title),
knownFields = [
"bag", "created", "creator", "modified", "modifier", "permissions", "recipe", "revision", "tags", "text", "title", "type", "uri"
];
if(tiddler) {
$tw.utils.each(tiddler.fields,function(fieldValue,fieldName) {
var fieldString = fieldName === "tags" ?
tiddler.fields.tags :
tiddler.getFieldString(fieldName); // Tags must be passed as an array, not a string
if(knownFields.indexOf(fieldName) !== -1) {
// If it's a known field, just copy it across
result[fieldName] = fieldString;
} else {
// If it's unknown, put it in the "fields" field
result.fields = result.fields || {};
result.fields[fieldName] = fieldString;
}
});
}
// Convert the type "text/x-tiddlywiki" into null
if(result.type === "text/x-tiddlywiki") {
result.type = null;
}
return JSON.stringify(result,null,$tw.config.preferences.jsonSpaces);
};
/*
Extract the revision from the Etag header of a request
*/
TiddlyWebSyncer.prototype.getRevisionFromEtag = function(request) {
var etag = request.getResponseHeader("Etag");
if(etag) {
return etag.split("/")[2].split(":")[0]; // etags are like "system-images_public/unsyncedIcon/946151:9f11c278ccde3a3149f339f4a1db80dd4369fc04"
} else {
return 0;
}
};
/*
A quick and dirty HTTP function; to be refactored later. Options are:
url: URL to retrieve
type: GET, PUT, POST etc
callback: function invoked with (err,data)
*/
TiddlyWebSyncer.prototype.httpRequest = function(options) {
var type = options.type || "GET",
headers = options.headers || {accept: "application/json"},
request = new XMLHttpRequest(),
data = "",
f,results;
// Massage the data hashmap into a string
if(options.data) {
if(typeof options.data === "string") { // Already a string
data = options.data;
} else { // A hashmap of strings
results = [];
$tw.utils.each(options.data,function(dataItem,dataItemTitle) {
results.push(dataItemTitle + "=" + encodeURIComponent(dataItem));
});
data = results.join("&");
}
}
// Set up the state change handler
request.onreadystatechange = function() {
if(this.readyState === 4) {
if(this.status === 200) {
// Success!
options.callback(null,this.responseText,this);
return;
}
// Something went wrong
options.callback(new Error("XMLHttpRequest error: " + this.status));
}
};
// Make the request
request.open(type,options.url,true);
if(headers) {
$tw.utils.each(headers,function(header,headerTitle,object) {
request.setRequestHeader(headerTitle,header);
});
}
if(data && !$tw.utils.hop(headers,"Content-type")) {
request.setRequestHeader("Content-type","application/x-www-form-urlencoded; charset=UTF-8");
}
request.send(data);
return request;
};
/*
Retrieve the CSRF token from its cookie
*/
TiddlyWebSyncer.prototype.getCsrfToken = function() {
var regex = /^(?:.*; )?csrf_token=([^(;|$)]*)(?:;|$)/,
match = regex.exec(document.cookie),
csrf = null;
if (match && (match.length === 2)) {
csrf = match[1];
}
return csrf;
};
// Only export anything on the browser
if($tw.browser) {
exports.name = "tiddlywebsyncer";
exports.syncer = TiddlyWebSyncer;
}
})();