io/index.js

1// Copyright 2013 Selenium committers
2// Copyright 2013 Software Freedom Conservancy
3//
4// Licensed under the Apache License, Version 2.0 (the "License");
5// you may not use this file except in compliance with the License.
6// You may obtain a copy of the License at
7//
8// http://www.apache.org/licenses/LICENSE-2.0
9//
10// Unless required by applicable law or agreed to in writing, software
11// distributed under the License is distributed on an "AS IS" BASIS,
12// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13// See the License for the specific language governing permissions and
14// limitations under the License.
15
16var fs = require('fs'),
17 path = require('path'),
18 rimraf = require('rimraf'),
19 tmp = require('tmp');
20
21var promise = require('..').promise;
22
23
24var PATH_SEPARATOR = process.platform === 'win32' ? ';' : ':';
25
26
27// PUBLIC API
28
29
30
31/**
32 * Recursively removes a directory and all of its contents. This is equivalent
33 * to {@code rm -rf} on a POSIX system.
34 * @param {string} path Path to the directory to remove.
35 * @return {!promise.Promise} A promise to be resolved when the operation has
36 * completed.
37 */
38exports.rmDir = function(path) {
39 return new promise.Promise(function(fulfill, reject) {
40 var numAttempts = 0;
41 attemptRm();
42 function attemptRm() {
43 numAttempts += 1;
44 rimraf(path, function(err) {
45 if (err) {
46 if (err.code === 'ENOTEMPTY' && numAttempts < 2) {
47 attemptRm();
48 return;
49 }
50 reject(err);
51 } else {
52 fulfill();
53 }
54 });
55 }
56 });
57};
58
59
60/**
61 * Copies one file to another.
62 * @param {string} src The source file.
63 * @param {string} dst The destination file.
64 * @return {!promise.Promise.<string>} A promise for the copied file's path.
65 */
66exports.copy = function(src, dst) {
67 var copied = promise.defer();
68
69 var rs = fs.createReadStream(src);
70 rs.on('error', copied.reject);
71 rs.on('end', function() {
72 copied.fulfill(dst);
73 });
74
75 var ws = fs.createWriteStream(dst);
76 ws.on('error', copied.reject);
77
78 rs.pipe(ws);
79
80 return copied.promise;
81};
82
83
84/**
85 * Recursively copies the contents of one directory to another.
86 * @param {string} src The source directory to copy.
87 * @param {string} dst The directory to copy into.
88 * @param {(RegEx|function(string): boolean)=} opt_exclude An exclusion filter
89 * as either a regex or predicate function. All files matching this filter
90 * will not be copied.
91 * @return {!promise.Promise.<string>} A promise for the destination
92 * directory's path once all files have been copied.
93 */
94exports.copyDir = function(src, dst, opt_exclude) {
95 var predicate = opt_exclude;
96 if (opt_exclude && typeof opt_exclude !== 'function') {
97 predicate = function(p) {
98 return !opt_exclude.test(p);
99 };
100 }
101
102 // TODO(jleyba): Make this function completely async.
103 if (!fs.existsSync(dst)) {
104 fs.mkdirSync(dst);
105 }
106
107 var files = fs.readdirSync(src);
108 files = files.map(function(file) {
109 return path.join(src, file);
110 });
111
112 if (predicate) {
113 files = files.filter(predicate);
114 }
115
116 var results = [];
117 files.forEach(function(file) {
118 var stats = fs.statSync(file);
119 var target = path.join(dst, path.basename(file));
120
121 if (stats.isDirectory()) {
122 if (!fs.existsSync(target)) {
123 fs.mkdirSync(target, stats.mode);
124 }
125 results.push(exports.copyDir(file, target, predicate));
126 } else {
127 results.push(exports.copy(file, target));
128 }
129 });
130
131 return promise.all(results).then(function() {
132 return dst;
133 });
134};
135
136
137/**
138 * Tests if a file path exists.
139 * @param {string} path The path to test.
140 * @return {!promise.Promise.<boolean>} A promise for whether the file exists.
141 */
142exports.exists = function(path) {
143 var result = promise.defer();
144 fs.exists(path, result.fulfill);
145 return result.promise;
146};
147
148
149/**
150 * Deletes a name from the filesystem and possibly the file it refers to. Has
151 * no effect if the file does not exist.
152 * @param {string} path The path to remove.
153 * @return {!promise.Promise} A promise for when the file has been removed.
154 */
155exports.unlink = function(path) {
156 return new promise.Promise(function(fulfill, reject) {
157 fs.exists(path, function(exists) {
158 if (exists) {
159 fs.unlink(path, function(err) {
160 err && reject(err) || fulfill();
161 });
162 } else {
163 fulfill();
164 }
165 });
166 });
167};
168
169
170/**
171 * @return {!promise.Promise.<string>} A promise for the path to a temporary
172 * directory.
173 * @see https://www.npmjs.org/package/tmp
174 */
175exports.tmpDir = function() {
176 return promise.checkedNodeCall(tmp.dir);
177};
178
179
180/**
181 * @param {{postfix: string}=} opt_options Temporary file options.
182 * @return {!promise.Promise.<string>} A promise for the path to a temporary
183 * file.
184 * @see https://www.npmjs.org/package/tmp
185 */
186exports.tmpFile = function(opt_options) {
187 // |tmp.file| checks arguments length to detect options rather than doing a
188 // truthy check, so we must only pass options if there are some to pass.
189 return opt_options ?
190 promise.checkedNodeCall(tmp.file, opt_options) :
191 promise.checkedNodeCall(tmp.file);
192};
193
194
195/**
196 * Searches the {@code PATH} environment variable for the given file.
197 * @param {string} file The file to locate on the PATH.
198 * @param {boolean=} opt_checkCwd Whether to always start with the search with
199 * the current working directory, regardless of whether it is explicitly
200 * listed on the PATH.
201 * @return {?string} Path to the located file, or {@code null} if it could
202 * not be found.
203 */
204exports.findInPath = function(file, opt_checkCwd) {
205 if (opt_checkCwd) {
206 var tmp = path.join(process.cwd(), file);
207 if (fs.existsSync(tmp)) {
208 return tmp;
209 }
210 }
211
212 var dirs = process.env['PATH'].split(PATH_SEPARATOR);
213 var found = null;
214 dirs.forEach(function(dir) {
215 var tmp = path.join(dir, file);
216 if (!found && fs.existsSync(tmp)) {
217 found = tmp;
218 }
219 });
220 return found;
221};