enigma-bbs/core/archive_util.js

272 lines
6.7 KiB
JavaScript

/* jslint node: true */
'use strict';
// ENiGMA½
const Config = require('./config.js').config;
const stringFormat = require('./string_format.js');
const Errors = require('./enig_error.js').Errors;
const resolveMimeType = require('./mime_util.js').resolveMimeType;
// base/modules
const fs = require('fs');
const _ = require('lodash');
const pty = require('ptyw.js');
let archiveUtil;
class Archiver {
constructor(config) {
this.compress = config.compress;
this.decompress = config.decompress;
this.list = config.list;
this.extract = config.extract;
}
ok() {
return this.canCompress() && this.canDecompress();
}
can(what) {
if(!_.has(this, [ what, 'cmd' ]) || !_.has(this, [ what, 'args' ])) {
return false;
}
return _.isString(this[what].cmd) && Array.isArray(this[what].args) && this[what].args.length > 0;
}
canCompress() { return this.can('compress'); }
canDecompress() { return this.can('decompress'); }
canList() { return this.can('list'); } // :TODO: validate entryMatch
canExtract() { return this.can('extract'); }
}
module.exports = class ArchiveUtil {
constructor() {
this.archivers = {};
this.longestSignature = 0;
}
// singleton access
static getInstance() {
if(!archiveUtil) {
archiveUtil = new ArchiveUtil();
archiveUtil.init();
}
return archiveUtil;
}
init() {
//
// Load configuration
//
if(_.has(Config, 'archives.archivers')) {
Object.keys(Config.archives.archivers).forEach(archKey => {
const archConfig = Config.archives.archivers[archKey];
const archiver = new Archiver(archConfig);
if(!archiver.ok()) {
// :TODO: Log warning - bad archiver/config
}
this.archivers[archKey] = archiver;
});
}
if(_.isObject(Config.fileTypes)) {
Object.keys(Config.fileTypes).forEach(mimeType => {
const fileType = Config.fileTypes[mimeType];
if(fileType.sig) {
fileType.sig = new Buffer(fileType.sig, 'hex');
fileType.offset = fileType.offset || 0;
// :TODO: this is broken: sig is NOT this long, it's sig.length long; offset needs to allow for -negative values as well
const sigLen =fileType.offset + fileType.sig.length;
if(sigLen > this.longestSignature) {
this.longestSignature = sigLen;
}
}
});
}
}
getArchiver(mimeTypeOrExtension) {
mimeTypeOrExtension = resolveMimeType(mimeTypeOrExtension);
if(!mimeTypeOrExtension) { // lookup returns false on failure
return;
}
const archiveHandler = _.get( Config, [ 'fileTypes', mimeTypeOrExtension, 'archiveHandler'] );
if(archiveHandler) {
return _.get( Config, [ 'archives', 'archivers', archiveHandler ] );
}
}
haveArchiver(archType) {
return this.getArchiver(archType) ? true : false;
}
detectTypeWithBuf(buf, cb) {
// :TODO: implement me!
}
detectType(path, cb) {
fs.open(path, 'r', (err, fd) => {
if(err) {
return cb(err);
}
const buf = new Buffer(this.longestSignature);
fs.read(fd, buf, 0, buf.length, 0, (err, bytesRead) => {
if(err) {
return cb(err);
}
const archFormat = _.findKey(Config.fileTypes, fileTypeInfo => {
if(!fileTypeInfo.sig) {
return false;
}
const lenNeeded = fileTypeInfo.offset + fileTypeInfo.sig.length;
if(bytesRead < lenNeeded) {
return false;
}
const comp = buf.slice(fileTypeInfo.offset, fileTypeInfo.offset + fileTypeInfo.sig.length);
return (fileTypeInfo.sig.equals(comp));
});
return cb(archFormat ? null : Errors.General('Unknown type'), archFormat);
});
});
}
spawnHandler(proc, action, cb) {
// pty.js doesn't currently give us a error when things fail,
// so we have this horrible, horrible hack:
let err;
proc.once('data', d => {
if(_.isString(d) && d.startsWith('execvp(3) failed.')) {
err = Errors.ExternalProcess(`${action} failed: ${d.trim()}`);
}
});
proc.once('exit', exitCode => {
return cb(exitCode ? Errors.ExternalProcess(`${action} failed with exit code: ${exitCode}`) : err);
});
}
compressTo(archType, archivePath, files, cb) {
const archiver = this.getArchiver(archType);
if(!archiver) {
return cb(Errors.Invalid(`Unknown archive type: ${archType}`));
}
const fmtObj = {
archivePath : archivePath,
fileList : files.join(' '), // :TODO: probably need same hack as extractTo here!
};
const args = archiver.compress.args.map( arg => stringFormat(arg, fmtObj) );
const proc = pty.spawn(archiver.compress.cmd, args, this.getPtyOpts());
return this.spawnHandler(proc, 'Compression', cb);
}
extractTo(archivePath, extractPath, archType, fileList, cb) {
let haveFileList;
if(!cb && _.isFunction(fileList)) {
cb = fileList;
fileList = [];
haveFileList = false;
} else {
haveFileList = true;
}
const archiver = this.getArchiver(archType);
if(!archiver) {
return cb(Errors.Invalid(`Unknown archive type: ${archType}`));
}
const fmtObj = {
archivePath : archivePath,
extractPath : extractPath,
};
const action = haveFileList ? 'extract' : 'decompress';
// we need to treat {fileList} special in that it should be broken up to 0:n args
const args = archiver[action].args.map( arg => {
return '{fileList}' === arg ? arg : stringFormat(arg, fmtObj);
});
const fileListPos = args.indexOf('{fileList}');
if(fileListPos > -1) {
// replace {fileList} with 0:n sep file list arguments
args.splice.apply(args, [fileListPos, 1].concat(fileList));
}
const proc = pty.spawn(archiver[action].cmd, args, this.getPtyOpts());
return this.spawnHandler(proc, (haveFileList ? 'Extraction' : 'Decompression'), cb);
}
listEntries(archivePath, archType, cb) {
const archiver = this.getArchiver(archType);
if(!archiver) {
return cb(Errors.Invalid(`Unknown archive type: ${archType}`));
}
const fmtObj = {
archivePath : archivePath,
};
const args = archiver.list.args.map( arg => stringFormat(arg, fmtObj) );
const proc = pty.spawn(archiver.list.cmd, args, this.getPtyOpts());
let output = '';
proc.on('data', data => {
// :TODO: hack for: execvp(3) failed.: No such file or directory
output += data;
});
proc.once('exit', exitCode => {
if(exitCode) {
return cb(Errors.ExternalProcess(`List failed with exit code: ${exitCode}`));
}
const entryGroupOrder = archiver.list.entryGroupOrder || { byteSize : 1, fileName : 2 };
const entries = [];
const entryMatchRe = new RegExp(archiver.list.entryMatch, 'gm');
let m;
while((m = entryMatchRe.exec(output))) {
entries.push({
byteSize : parseInt(m[entryGroupOrder.byteSize]),
fileName : m[entryGroupOrder.fileName].trim(),
});
}
return cb(null, entries);
});
}
getPtyOpts() {
return {
// :TODO: cwd
name : 'enigma-archiver',
cols : 80,
rows : 24,
env : process.env,
};
}
};