Nodejs File Copy fs_copy(source, dest, callback)

Method Source Code

var FS = require("fs");
var PATH = require("path");


function defaults(args, defs) {
    var ret = {};
    for (var i in defs)
        ret[i] = args.hasOwnProperty(i) ? args[i] : defs[i];
    return ret;//w w  w.  j a v  a  2  s.c  om
};

function shallow_copy(src, dest) {
    if (dest == null) dest = {};
    for (var i in src) dest[i] = src[i];
    return dest;
};

// filesystem operations

function fs_ensure_directory(dir, callback) {
    dir = PATH.normalize(dir);
    try {
        if (FS.statSync(dir).isDirectory()) return callback(null, dir);
        else callback(new Error("fs_ensure_directory: " + dir + " exists and is not a directory!"));
    } catch(ex) {
        fs_ensure_directory(PATH.dirname(dir), function(err){
            if (err) return callback(err);
            FS.mkdirSync(dir, 0755);
            callback(null, dir);
        });
    }
};

function fs_copylist(files, dest, callback) {
    function cont(err) {
        if (err) return callback(err);
        if (++copied == files.length) callback();
    };
    var copied = 0;
    for (var i = files.length; --i >= 0;)
        fs_copy(files[i], dest, cont);
};

var copy_in_progress = 0;
function fs_copy(source, dest, callback) {
    // we have to place some limit on the max number of files we copy
    // at once, to avoid the "EMFILE" error.
    //
    // http://stackoverflow.com/questions/8965606/node-and-error-emfile-too-many-open-files
    //
    // tried "graceful-fs" but it doesn't really work..
    if (copy_in_progress >= 150) {
        setTimeout(function(){
            fs_copy(source, dest, callback);
        }, 10);
    } else {
        ++copy_in_progress;
        _fs_do_copy(source, dest, function(){
            --copy_in_progress;
            return callback.apply(this, arguments);
        });
    }
}

function _fs_do_copy(source, dest, callback) {
    if (source instanceof Array)
        return fs_copylist(source, dest, callback);
    fs_ensure_directory(PATH.dirname(dest), function(err){
        if (err) return callback(err);
        FS.lstat(source, function(err, stat){
            if (err) return callback(err);
            else if (stat.isDirectory()) {
                dest = PATH.join(dest, PATH.basename(source));
                return fs_ensure_directory(dest, function(){
                    fs_copytree(source, dest, callback);
                });
            }
            else if (stat.isSymbolicLink()) {
                FS.readlink(source, function(err, data){
                    if (err) return callback(err);
                    FS.lstat(dest, function(err, stat){
                        if (err && err.code != "ENOENT") return callback(err);
                        if (!err && stat.isDirectory()) {
                            dest = PATH.join(dest, PATH.basename(source));
                        }
                        FS.symlink(data, dest, callback);
                    });
                });
            }
            else FS.readFile(source, function(err, data){
                if (err) return callback(err);
                FS.stat(dest, function(err, stat){
                    if (err && err.code != "ENOENT") return callback(err);
                    if (!err && stat.isDirectory()) {
                        dest = PATH.join(dest, PATH.basename(source));
                    }
                    FS.writeFile(dest, data, callback);
                });
            });
        });
    });
};

function fs_copytree(source, dest, options) {
    if (!options) options = {};
    if (typeof options == "function") options = {
        callback: options
    };
    if (!options.callback) options.callback = function(err) {
        if (err) throw err;
    };
    var finished = false, count = 0;
    var args = {
        callback: function(err, f) {
            if (err) return options.callback(err);
            if (!f.stat.isDirectory()) {
                ++count;
                fs_copy(f.full, PATH.join(dest, f.rel), function(err){
                    if (err) return options.callback(err);
                    --count;
                    if (finished && count == 0)
                        options.callback();
                });
            }
        },
        filter: options.filter,
        recurse: options.recurse,
        finish: function() {
            finished = true;
        }
    };
    fs_find(source, args);
};

function is_vcs_dir(name) {
    return (/^(\.git|\.hg|\.bzr|SVN|CVS|_darcs)$/.test(name));
};

function fs_find(dir, options, prefix, level, finish) {
    if (dir == null) dir = process.cwd();
    if (prefix == null) prefix = ".";
    if (level == null) {
        level = 0;
        finish = options.finish || function(){};
    }
    FS.readdir(dir, function(err, ret){
        if (err) return options.callback(err);
        var async_calls = ret.length;
        if (async_calls == 0) {
            finish();
            return;
        }
        ret.forEach(function(name){
            var fullname = PATH.join(dir, name);
            FS.stat(fullname, function(err, stat){
                if (err) {
                    options.callback(err);
                } else {
                    var rel = PATH.join(prefix, name);
                    var f = {
                        name : name,
                        full : fullname,
                        stat : stat,
                        dir  : dir,
                        rel  : rel
                    };
                    if (!options.filter || options.filter(f))
                        options.callback(null, f);
                    if (stat.isDirectory()
                        && (!options.recurse || options.recurse(f))
                        && (!options.skip_vcs || !is_vcs_dir(fullname)))
                    {
                        fs_find(fullname, options, rel, level + 1, function(){
                            if (--async_calls == 0)
                                finish();
                        });
                        return;
                    }
                }
                if (--async_calls == 0) finish();
            });
        });
    });
};

function fs_rmpath(dir, callback, deep) {
    FS.stat(dir, function(err, stat){
        if (err) return deep ? callback(err) : callback();
        if (stat.isDirectory()) {
            FS.readdir(dir, function(err, entries){
                if (err) return callback(err);
                function cont() {
                    FS.rmdir(dir, function(err){
                        if (err) return callback(err);
                        callback();
                    });
                };
                var n = entries.length;
                if (n == 0) cont();
                else entries.forEach(function(e){
                    fs_rmpath(PATH.join(dir, e), function(err){
                        if (err) return callback(err);
                        if (--n == 0) cont();
                    }, true);
                });
            });
        } else {
            FS.unlink(dir, function(err){
                if (err) return callback(err);
                callback();
            });
        }
    });
};

function fs_rmpathSync(x) {
    var stat = FS.statSync(x);
    if (!stat.isDirectory()) {
        FS.unlinkSync(x);
    } else {
        FS.readdirSync(x).forEach(function(file){
            fs_rmpathSync(PATH.join(x, file));
        });
        FS.rmdirSync(x);
    }
};