TiddlyWiki5/archive/js/LocalFileSync.js

150 wiersze
4.3 KiB
JavaScript

/*\
title: js/LocalFileSync.js
Loads tiddlers from a given directory, and then keeps the files up to date as tiddlers are modified, created or deleted.
\*/
(function(){
/*jslint node: true */
"use strict";
var retrieveFile = require("./FileRetriever.js").retrieveFile,
utils = require("./Utils.js"),
fs = require("fs"),
path = require("path"),
url = require("url"),
util = require("util"),
async = require("async");
function LocalFileSync(dirpath,store,callback) {
this.dirpath = dirpath;
this.store = store;
this.callback = callback;
this.tiddlers = {}; // A hashmap of <tiddlername>: {changeCount: <changeCount>, files: [name]}
var self = this,
sanitizeFilepath = function(filepath) {
return filepath.replace(/\//mg,"-");
};
// Set up a queue for loading tiddler files, tasks are {filepath:,callback:}
this.loadQueue = async.queue(function(task,callback) {
task.files = [];
retrieveFile(task.filepath,self.dirpath,function(err,data) {
if(err) {
callback(err);
} else {
task.files.push(task.filepath);
// Use the filepath as the default title for the tiddler
var fields = {
title: data.path
};
var tiddlers = self.store.deserializeTiddlers(data.extname,data.text,fields);
// Check for the .meta file
if(data.extname !== ".json" && tiddlers.length === 1) {
var metafile = task.filepath + ".meta";
retrieveFile(metafile,self.dirpath,function(err,data) {
if(err && err.code !== "ENOENT" && err.code !== "404") {
callback(err);
} else {
task.files.push(metafile);
var fields = tiddlers[0];
if(!err) {
var text = data.text.split("\n\n")[0];
if(text) {
fields = self.store.deserializeTiddlers("application/x-tiddler",text,fields)[0];
}
}
task.callback(task,[fields]);
callback(null);
}
});
} else {
task.callback(task,tiddlers);
callback(null);
}
}
});
},10);
// Call the callback when all the files are loaded
this.loadQueue.drain = function() {
callback(null);
};
// Query the folder content to get all the tiddlers
fs.readdir(this.dirpath,function(err,files) {
if(err) {
callback(err);
} else {
var loadCallback = function(task,tiddlers) {
for(var t=0; t<tiddlers.length; t++) {
var tiddler = tiddlers[t];
self.store.addTiddler(tiddler);
self.tiddlers[tiddler.title] = {
changeCount: self.store.getChangeCount(tiddler.title),
files: task.files
};
}
};
for(var t=0; t<files.length; t++) {
var f = files[t];
if(["..",".",".DS_Store"].indexOf(f) === -1 && f.indexOf(".meta") !== f.length-5) {
self.loadQueue.push({
filepath: f,
callback: loadCallback
});
}
}
}
});
// Set up a queue for saving tiddler files
this.saveQueue = async.queue(function(task,callback) {
var data = task.data,
encoding = "utf8";
if(task.binary) {
data = new Buffer(task.data,"base64").toString("binary");
encoding = "binary";
}
fs.writeFile(self.dirpath + "/" + task.name,data,encoding,function(err) {
callback(err);
});
},10);
// Install our event listener to listen out for tiddler changes
this.store.addEventListener("",function(changes) {
var t;
for(var title in changes) {
// Get the information about the tiddler
var tiddler = self.store.getTiddler(title),
changeCount = self.store.getChangeCount(title),
tiddlerInfo = self.tiddlers[title],
files = [];
if(tiddler) {
// Construct a changecount record if we don't have one
if(!tiddlerInfo) {
tiddlerInfo = {changeCount: 0, files: []};
self.tiddlers[title] = tiddlerInfo;
}
// Save the tiddler if the changecount has increased
if(changeCount > tiddlerInfo.changeCount) {
files = self.store.serializeTiddlers([tiddler],"application/x-tiddler");
for(t=0; t<files.length; t++) {
files[t].name = sanitizeFilepath(files[t].name);
tiddlerInfo.files.push(files[t].name);
self.saveQueue.push(files[t]);
}
}
} else {
// Delete the tiddler file if the tiddler has gone
if(tiddlerInfo) {
for(t=0; t<tiddlerInfo.files.length; t++) {
fs.unlink(self.dirpath + "/" + tiddlerInfo.files[t]);
}
delete self.tiddlers[title];
}
}
}
});
}
exports.LocalFileSync = LocalFileSync;
})();