cryptpad/storage/file.js

649 lines
22 KiB
JavaScript

/*@flow*/
/* jshint esversion: 6 */
/* global Buffer */
var Fs = require("fs");
var Fse = require("fs-extra");
var Path = require("path");
var nThen = require("nthen");
var Semaphore = require("saferphore");
const ToPull = require('stream-to-pull-stream');
const Pull = require('pull-stream');
const isValidChannelId = function (id) {
return typeof(id) === 'string' &&
id.length >= 32 && id.length < 50 &&
/^[a-zA-Z0-9=+-]*$/.test(id);
};
// 511 -> octal 777
// read, write, execute permissions flag
const PERMISSIVE = 511;
var mkPath = function (env, channelId) {
return Path.join(env.root, channelId.slice(0, 2), channelId) + '.ndjson';
};
var mkArchivePath = function (env, channelId) {
return Path.join(env.archiveRoot, 'datastore', channelId.slice(0, 2), channelId) + '.ndjson';
};
var getMetadataAtPath = function (Env, path, cb) {
var remainder = '';
var stream = Fs.createReadStream(path, { encoding: 'utf8' });
var complete = function (err, data) {
var _cb = cb;
cb = undefined;
if (_cb) { _cb(err, data); }
};
stream.on('data', function (chunk) {
if (!/\n/.test(chunk)) {
remainder += chunk;
return;
}
stream.close();
var metadata = chunk.split('\n')[0];
var parsed = null;
try {
parsed = JSON.parse(metadata);
complete(undefined, parsed);
}
catch (e) {
console.log("getMetadataAtPath");
console.error(e);
complete('INVALID_METADATA');
}
});
stream.on('end', function () {
complete();
});
stream.on('error', function (e) { complete(e); });
};
var getChannelMetadata = function (Env, channelId, cb) {
var path = mkPath(Env, channelId);
getMetadataAtPath(Env, path, cb);
};
var closeChannel = function (env, channelName, cb) {
if (!env.channels[channelName]) { return void cb(); }
try {
env.channels[channelName].writeStream.close();
delete env.channels[channelName];
env.openFiles--;
cb();
} catch (err) {
cb(err);
}
};
var clearChannel = function (env, channelId, cb) {
var path = mkPath(env, channelId);
getMetadataAtPath(env, path, function (e, metadata) {
if (e) { return cb(new Error(e)); }
if (!metadata) {
return void Fs.truncate(path, 0, function (err) {
if (err) {
return cb(err);
}
cb(void 0);
});
}
var len = JSON.stringify(metadata).length + 1;
// as long as closeChannel is synchronous, this should not cause
// any race conditions. truncate ought to return faster than a channel
// can be opened and read by another user. if that turns out not to be
// the case, we'll need to implement locking.
closeChannel(env, channelId, function (err) {
if (err) { cb(err); }
Fs.truncate(path, len, function (err) {
if (err) { return cb(err); }
cb();
});
});
});
};
var readMessages = function (path, msgHandler, cb) {
var remainder = '';
var stream = Fs.createReadStream(path, { encoding: 'utf8' });
var complete = function (err) {
var _cb = cb;
cb = undefined;
if (_cb) { _cb(err); }
};
stream.on('data', function (chunk) {
var lines = chunk.split('\n');
lines[0] = remainder + lines[0];
remainder = lines.pop();
lines.forEach(msgHandler);
});
stream.on('end', function () {
msgHandler(remainder);
complete();
});
stream.on('error', function (e) { complete(e); });
};
const NEWLINE_CHR = ('\n').charCodeAt(0);
const mkBufferSplit = () => {
let remainder = null;
return Pull((read) => {
return (abort, cb) => {
read(abort, function (end, data) {
if (end) {
if (data) { console.log("mkBufferSplit() Data at the end"); }
cb(end, remainder ? [remainder, data] : [data]);
remainder = null;
return;
}
const queue = [];
for (;;) {
const offset = data.indexOf(NEWLINE_CHR);
if (offset < 0) {
remainder = remainder ? Buffer.concat([remainder, data]) : data;
break;
}
let subArray = data.slice(0, offset);
if (remainder) {
subArray = Buffer.concat([remainder, subArray]);
remainder = null;
}
queue.push(subArray);
data = data.slice(offset + 1);
}
cb(end, queue);
});
};
}, Pull.flatten());
};
const mkOffsetCounter = () => {
let offset = 0;
return Pull.map((buff) => {
const out = { offset: offset, buff: buff };
// +1 for the eaten newline
offset += buff.length + 1;
return out;
});
};
const readMessagesBin = (env, id, start, msgHandler, cb) => {
const stream = Fs.createReadStream(mkPath(env, id), { start: start });
// TODO get the channel and add the atime
let keepReading = true;
Pull(
ToPull.read(stream),
mkBufferSplit(),
mkOffsetCounter(),
Pull.asyncMap((data, moreCb) => {
msgHandler(data, moreCb, () => { keepReading = false; moreCb(); });
}),
Pull.drain(() => (keepReading), (err) => {
cb((keepReading) ? err : undefined);
})
);
};
var checkPath = function (path, callback) {
// TODO check if we actually need to use stat at all
Fs.stat(path, function (err) {
if (!err) {
callback(undefined, true);
return;
}
if (err.code !== 'ENOENT') {
callback(err);
return;
}
Fse.mkdirp(Path.dirname(path), PERMISSIVE, function (err) {
if (err && err.code !== 'EEXIST') {
callback(err);
return;
}
callback(undefined, false);
});
});
};
var removeChannel = function (env, channelName, cb) {
var filename = mkPath(env, channelName);
Fs.unlink(filename, cb);
};
// pass in the path so we can reuse the same function for archived files
var channelExists = function (filepath, channelName, cb) {
Fs.stat(filepath, function (err, stat) {
if (err) {
if (err.code === 'ENOENT') {
// no, the file doesn't exist
return void cb(void 0, false);
}
return void cb(err);
}
if (!stat.isFile()) { return void cb("E_NOT_FILE"); }
return void cb(void 0, true);
});
};
var removeArchivedChannel = function (env, channelName, cb) {
var filename = mkArchivePath(env, channelName);
Fs.unlink(filename, cb);
};
var listChannels = function (root, handler, cb) {
// do twenty things at a time
var sema = Semaphore.create(20);
var dirList = [];
nThen(function (w) {
// the root of your datastore contains nested directories...
Fs.readdir(root, w(function (err, list) {
if (err) {
w.abort();
// TODO check if we normally return strings or errors
return void cb(err);
}
dirList = list;
}));
}).nThen(function (w) {
// search inside the nested directories
// stream it so you don't put unnecessary data in memory
var wait = w();
dirList.forEach(function (dir) {
sema.take(function (give) {
var nestedDirPath = Path.join(root, dir);
Fs.readdir(nestedDirPath, w(give(function (err, list) {
if (err) { return void handler(err); } // Is this correct?
list.forEach(function (item) {
// ignore things that don't match the naming pattern
if (/^\./.test(item) || !/[0-9a-fA-F]{32,}\.ndjson$/.test(item)) { return; }
var filepath = Path.join(nestedDirPath, item);
var channel = filepath.replace(/\.ndjson$/, '').replace(/.*\//, '');
if ([32, 34].indexOf(channel.length) === -1) { return; }
// otherwise throw it on the pile
sema.take(function (give) {
var next = w(give());
Fs.stat(filepath, w(function (err, stats) {
if (err) {
return void handler(err);
}
handler(void 0, {
channel: channel,
atime: stats.atime,
mtime: stats.mtime,
ctime: stats.ctime,
size: stats.size,
}, next);
}));
});
});
})));
});
});
wait();
}).nThen(function () {
cb();
});
};
// move a channel's log file from its current location
// to an equivalent location in the cold storage directory
var archiveChannel = function (env, channelName, cb) {
if (!env.retainData) {
return void cb("ARCHIVES_DISABLED");
}
// ctime is the most reliable indicator of when a file was archived
// because it is used to indicate changes to the files metadata
// and not its contents
// if we find that this is not reliable in production, we can update it manually
// https://nodejs.org/api/fs.html#fs_fs_utimes_path_atime_mtime_callback
// check what the channel's path should be (in its current location)
var currentPath = mkPath(env, channelName);
// construct a parallel path in the new location
var archivePath = mkArchivePath(env, channelName);
// use Fse.move to move it, Fse makes paths to the directory when you use it.
// https://github.com/jprichardson/node-fs-extra/blob/HEAD/docs/move.md
Fse.move(currentPath, archivePath, { overwrite: true }, cb);
};
var unarchiveChannel = function (env, channelName, cb) {
// very much like 'archiveChannel' but in the opposite direction
// the file is currently archived
var currentPath = mkArchivePath(env, channelName);
var unarchivedPath = mkPath(env, channelName);
// if a file exists in the unarchived path, you probably don't want to clobber its data
// so unlike 'archiveChannel' we won't overwrite.
// Fse.move will call back with EEXIST in such a situation
Fse.move(currentPath, unarchivedPath, cb);
};
var flushUnusedChannels = function (env, cb, frame) {
var currentTime = +new Date();
var expiration = typeof(frame) === 'undefined'? env.channelExpirationMs: frame;
Object.keys(env.channels).forEach(function (chanId) {
var chan = env.channels[chanId];
if (typeof(chan.atime) !== 'number') { return; }
if (currentTime >= expiration + chan.atime) {
closeChannel(env, chanId, function (err) {
if (err) {
console.error(err);
return;
}
if (env.verbose) {
console.log("Closed channel [%s]", chanId);
}
});
}
});
cb();
};
var channelBytes = function (env, chanName, cb) {
var path = mkPath(env, chanName);
Fs.stat(path, function (err, stats) {
if (err) { return void cb(err); }
cb(undefined, stats.size);
});
};
/*::
export type ChainPadServer_ChannelInternal_t = {
atime: number,
writeStream: typeof(process.stdout),
whenLoaded: ?Array<(err:?Error, chan:?ChainPadServer_ChannelInternal_t)=>void>,
onError: Array<(?Error)=>void>,
path: string
};
*/
var getChannel = function (
env,
id,
callback /*:(err:?Error, chan:?ChainPadServer_ChannelInternal_t)=>void*/
) {
if (env.channels[id]) {
var chan = env.channels[id];
chan.atime = +new Date();
if (chan.whenLoaded) {
chan.whenLoaded.push(callback);
} else {
callback(undefined, chan);
}
return;
}
if (env.openFiles >= env.openFileLimit) {
// if you're running out of open files, asynchronously clean up expired files
// do it on a shorter timeframe, though (half of normal)
setTimeout(function () {
flushUnusedChannels(env, function () {
if (env.verbose) {
console.log("Approaching open file descriptor limit. Cleaning up");
}
}, env.channelExpirationMs / 2);
});
}
var path = mkPath(env, id);
var channel /*:ChainPadServer_ChannelInternal_t*/ = env.channels[id] = {
atime: +new Date(),
writeStream: (undefined /*:any*/),
whenLoaded: [ callback ],
onError: [ ],
path: path
};
var complete = function (err) {
var whenLoaded = channel.whenLoaded;
// no guarantee stream.on('error') will not cause this to be called multiple times
if (!whenLoaded) { return; }
channel.whenLoaded = undefined;
if (err) {
delete env.channels[id];
}
if (!channel.writeStream) {
throw new Error("getChannel() complete called without channel writeStream");
}
whenLoaded.forEach(function (wl) { wl(err, (err) ? undefined : channel); });
};
var fileExists;
var errorState;
nThen(function (waitFor) {
checkPath(path, waitFor(function (err, exists) {
if (err) {
errorState = true;
complete(err);
return;
}
fileExists = exists;
}));
}).nThen(function (waitFor) {
if (errorState) { return; }
var stream = channel.writeStream = Fs.createWriteStream(path, { flags: 'a' });
env.openFiles++;
stream.on('open', waitFor());
stream.on('error', function (err /*:?Error*/) {
env.openFiles--;
// this might be called after this nThen block closes.
if (channel.whenLoaded) {
complete(err);
} else {
channel.onError.forEach(function (handler) {
handler(err);
});
}
});
}).nThen(function () {
if (errorState) { return; }
complete();
});
};
const messageBin = (env, chanName, msgBin, cb) => {
getChannel(env, chanName, function (err, chan) {
if (!chan) {
cb(err);
return;
}
let called = false;
var complete = function (err) {
if (called) { return; }
called = true;
cb(err);
};
chan.onError.push(complete);
chan.writeStream.write(msgBin, function () {
/*::if (!chan) { throw new Error("Flow unreachable"); }*/
chan.onError.splice(chan.onError.indexOf(complete), 1);
if (!cb) { return; }
//chan.messages.push(msg);
chan.atime = +new Date(); // FIXME seems like odd behaviour that not passing a callback would result in not updating atime...
complete();
});
});
};
var message = function (env, chanName, msg, cb) {
messageBin(env, chanName, new Buffer(msg + '\n', 'utf8'), cb);
};
var getMessages = function (env, chanName, handler, cb) {
getChannel(env, chanName, function (err, chan) {
if (!chan) {
cb(err);
return;
}
var errorState = false;
readMessages(chan.path, function (msg) {
if (!msg || errorState) { return; }
//console.log(msg);
try {
handler(msg);
} catch (e) {
errorState = true;
return void cb(err);
}
}, function (err) {
if (err) {
errorState = true;
return void cb(err);
}
if (!chan) { throw new Error("impossible, flow checking"); }
chan.atime = +new Date();
cb();
});
});
};
/*::
export type ChainPadServer_MessageObj_t = { buff: Buffer, offset: number };
export type ChainPadServer_Storage_t = {
readMessagesBin: (
channelName:string,
start:number,
asyncMsgHandler:(msg:ChainPadServer_MessageObj_t, moreCb:()=>void, abortCb:()=>void)=>void,
cb:(err:?Error)=>void
)=>void,
message: (channelName:string, content:string, cb:(err:?Error)=>void)=>void,
messageBin: (channelName:string, content:Buffer, cb:(err:?Error)=>void)=>void,
getMessages: (channelName:string, msgHandler:(msg:string)=>void, cb:(err:?Error)=>void)=>void,
removeChannel: (channelName:string, cb:(err:?Error)=>void)=>void,
closeChannel: (channelName:string, cb:(err:?Error)=>void)=>void,
flushUnusedChannels: (cb:()=>void)=>void,
getChannelSize: (channelName:string, cb:(err:?Error, size:?number)=>void)=>void,
getChannelMetadata: (channelName:string, cb:(err:?Error|string, data:?any)=>void)=>void,
clearChannel: (channelName:string, (err:?Error)=>void)=>void
};
export type ChainPadServer_Config_t = {
verbose?: boolean,
filePath?: string,
channelExpirationMs?: number,
openFileLimit?: number
};
*/
module.exports.create = function (
conf /*:ChainPadServer_Config_t*/,
cb /*:(store:ChainPadServer_Storage_t)=>void*/
) {
var env = {
root: conf.filePath || './datastore',
archiveRoot: conf.archivePath || './data/archive',
retainData: conf.retainData,
channels: { },
channelExpirationMs: conf.channelExpirationMs || 30000,
verbose: conf.verbose,
openFiles: 0,
openFileLimit: conf.openFileLimit || 2048,
};
var it;
nThen(function (w) {
// make sure the store's directory exists
Fse.mkdirp(env.root, PERMISSIVE, w(function (err) {
if (err && err.code !== 'EEXIST') {
throw err;
}
}));
// make sure the cold storage directory exists
Fse.mkdirp(env.archiveRoot, PERMISSIVE, w(function (err) {
if (err && err.code !== 'EEXIST') {
throw err;
}
}));
}).nThen(function () {
cb({
readMessagesBin: (channelName, start, asyncMsgHandler, cb) => {
if (!isValidChannelId(channelName)) { return void cb(new Error('EINVAL')); }
readMessagesBin(env, channelName, start, asyncMsgHandler, cb);
},
message: function (channelName, content, cb) {
if (!isValidChannelId(channelName)) { return void cb(new Error('EINVAL')); }
message(env, channelName, content, cb);
},
messageBin: (channelName, content, cb) => {
if (!isValidChannelId(channelName)) { return void cb(new Error('EINVAL')); }
messageBin(env, channelName, content, cb);
},
getMessages: function (channelName, msgHandler, cb) {
if (!isValidChannelId(channelName)) { return void cb(new Error('EINVAL')); }
getMessages(env, channelName, msgHandler, cb);
},
removeChannel: function (channelName, cb) {
if (!isValidChannelId(channelName)) { return void cb(new Error('EINVAL')); }
removeChannel(env, channelName, function (err) {
cb(err);
});
},
removeArchivedChannel: function (channelName, cb) {
if (!isValidChannelId(channelName)) { return void cb(new Error('EINVAL')); }
removeArchivedChannel(env, channelName, cb);
},
closeChannel: function (channelName, cb) {
if (!isValidChannelId(channelName)) { return void cb(new Error('EINVAL')); }
closeChannel(env, channelName, cb);
},
flushUnusedChannels: function (cb) {
flushUnusedChannels(env, cb);
},
getChannelSize: function (channelName, cb) {
if (!isValidChannelId(channelName)) { return void cb(new Error('EINVAL')); }
channelBytes(env, channelName, cb);
},
getChannelMetadata: function (channelName, cb) {
if (!isValidChannelId(channelName)) { return void cb(new Error('EINVAL')); }
getChannelMetadata(env, channelName, cb);
},
clearChannel: function (channelName, cb) {
if (!isValidChannelId(channelName)) { return void cb(new Error('EINVAL')); }
clearChannel(env, channelName, cb);
},
listChannels: function (handler, cb) {
listChannels(env.root, handler, cb);
},
isChannelAvailable: function (channelName, cb) {
if (!isValidChannelId(channelName)) { return void cb(new Error('EINVAL')); }
// construct the path
var filepath = mkPath(env, channelName);
channelExists(filepath, channelName, cb);
},
isChannelArchived: function (channelName, cb) {
if (!isValidChannelId(channelName)) { return void cb(new Error('EINVAL')); }
// construct the path
var filepath = mkArchivePath(env, channelName);
channelExists(filepath, channelName, cb);
},
listArchivedChannels: function (handler, cb) {
listChannels(Path.join(env.archiveRoot, 'datastore'), handler, cb);
},
archiveChannel: function (channelName, cb) {
if (!isValidChannelId(channelName)) { return void cb(new Error('EINVAL')); }
archiveChannel(env, channelName, cb);
},
restoreArchivedChannel: function (channelName, cb) {
if (!isValidChannelId(channelName)) { return void cb(new Error('EINVAL')); }
unarchiveChannel(env, channelName, cb);
},
log: function (channelName, content, cb) {
message(env, channelName, content, cb);
},
shutdown: function () {
clearInterval(it);
}
});
});
it = setInterval(function () {
flushUnusedChannels(env, function () { });
}, 5000);
};