pad.pub0.org/node/db/PadManager.js

165 lines
4.2 KiB
JavaScript

/**
* The Pad Manager is a Factory for pad Objects
*/
/*
* 2011 Peter 'Pita' Martischka (Primary Technology Ltd)
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS-IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
var ERR = require("async-stacktrace");
var customError = require("../utils/customError");
require("../db/Pad");
var db = require("./DB").db;
/**
* An Object containing all known Pads. Provides "get" and "set" functions,
* which should be used instead of indexing with brackets. These prepend a
* colon to the key, to avoid conflicting with built-in Object methods or with
* these functions themselves.
*
* If this is needed in other places, it would be wise to make this a prototype
* that's defined somewhere more sensible.
*/
var globalPads = {
get: function (name) { return this[':'+name]; },
set: function (name, value) { this[':'+name] = value; },
remove: function (name) { delete this[':'+name]; }
};
/**
* An array of padId transformations. These represent changes in pad name policy over
* time, and allow us to "play back" these changes so legacy padIds can be found.
*/
var padIdTransforms = [
[/\s+/g, '_']
];
/**
* Returns a Pad Object with the callback
* @param id A String with the id of the pad
* @param {Function} callback
*/
exports.getPad = function(id, text, callback)
{
//check if this is a valid padId
if(!exports.isValidPadId(id))
{
callback(new customError(id + " is not a valid padId","apierror"));
return;
}
//make text an optional parameter
if(typeof text == "function")
{
callback = text;
text = null;
}
//check if this is a valid text
if(text != null)
{
//check if text is a string
if(typeof text != "string")
{
callback(new customError("text is not a string","apierror"));
return;
}
//check if text is less than 100k chars
if(text.length > 100000)
{
callback(new customError("text must be less than 100k chars","apierror"));
return;
}
}
var pad = globalPads.get(id);
//return pad if its already loaded
if(pad != null)
{
callback(null, pad);
}
//try to load pad
else
{
pad = new Pad(id);
//initalize the pad
pad.init(text, function(err)
{
if(ERR(err, callback)) return;
globalPads.set(id, pad);
callback(null, pad);
});
}
}
//checks if a pad exists
exports.doesPadExists = function(padId, callback)
{
db.get("pad:"+padId, function(err, value)
{
if(ERR(err, callback)) return;
callback(null, value != null);
});
}
//returns a sanitized padId, respecting legacy pad id formats
exports.sanitizePadId = function(padId, callback) {
var transform_index = arguments[2] || 0;
//we're out of possible transformations, so just return it
if(transform_index >= padIdTransforms.length)
{
callback(padId);
}
//check if padId exists
else
{
exports.doesPadExists(padId, function(junk, exists)
{
if(exists)
{
callback(padId);
}
else
{
//get the next transformation *that's different*
var transformedPadId = padId;
while(transformedPadId == padId && transform_index < padIdTransforms.length)
{
transformedPadId = padId.replace(padIdTransforms[transform_index][0], padIdTransforms[transform_index][1]);
transform_index += 1;
}
//check the next transform
exports.sanitizePadId(transformedPadId, callback, transform_index);
}
});
}
}
exports.isValidPadId = function(padId)
{
return /^(g.[a-zA-Z0-9]{16}\$)?[^$]{1,50}$/.test(padId);
}
//removes a pad from the array
exports.unloadPad = function(padId)
{
if(globalPads.get(padId))
globalPads.remove(padId);
}