|
|
- <!doctype html>
- <html>
- <title>npm-scripts</title>
- <meta charset="utf-8">
- <link rel="stylesheet" type="text/css" href="../../static/style.css">
- <link rel="canonical" href="https://www.npmjs.org/doc/misc/npm-scripts.html">
- <script async=true src="../../static/toc.js"></script>
-
- <body>
- <div id="wrapper">
-
- <h1><a href="../misc/npm-scripts.html">npm-scripts</a></h1> <p>How npm handles the "scripts" field</p>
- <h2 id="description">DESCRIPTION</h2>
- <p>npm supports the "scripts" property of the package.json file, for the
- following scripts:</p>
- <ul>
- <li>prepublish:
- Run BEFORE the package is packed and published, as well as on local <code>npm
- install</code> without any arguments. (See below)</li>
- <li>prepare:
- Run both BEFORE the package is packed and published, and on local <code>npm
- install</code> without any arguments (See below). This is run
- AFTER <code>prepublish</code>, but BEFORE <code>prepublishOnly</code>.</li>
- <li>prepublishOnly:
- Run BEFORE the package is prepared and packed, ONLY on <code>npm publish</code>. (See
- below.)</li>
- <li>prepack:
- run BEFORE a tarball is packed (on <code>npm pack</code>, <code>npm publish</code>, and when
- installing git dependencies)</li>
- <li>postpack:
- Run AFTER the tarball has been generated and moved to its final destination.</li>
- <li>publish, postpublish:
- Run AFTER the package is published.</li>
- <li>preinstall:
- Run BEFORE the package is installed</li>
- <li>install, postinstall:
- Run AFTER the package is installed.</li>
- <li>preuninstall, uninstall:
- Run BEFORE the package is uninstalled.</li>
- <li>postuninstall:
- Run AFTER the package is uninstalled.</li>
- <li>preversion:
- Run BEFORE bumping the package version.</li>
- <li>version:
- Run AFTER bumping the package version, but BEFORE commit.</li>
- <li>postversion:
- Run AFTER bumping the package version, and AFTER commit.</li>
- <li>pretest, test, posttest:
- Run by the <code>npm test</code> command.</li>
- <li>prestop, stop, poststop:
- Run by the <code>npm stop</code> command.</li>
- <li>prestart, start, poststart:
- Run by the <code>npm start</code> command.</li>
- <li>prerestart, restart, postrestart:
- Run by the <code>npm restart</code> command. Note: <code>npm restart</code> will run the
- stop and start scripts if no <code>restart</code> script is provided.</li>
- <li>preshrinkwrap, shrinkwrap, postshrinkwrap:
- Run by the <code>npm shrinkwrap</code> command.</li>
- </ul>
- <p>Additionally, arbitrary scripts can be executed by running <code>npm
- run-script <stage></code>. <em>Pre</em> and <em>post</em> commands with matching
- names will be run for those as well (e.g. <code>premyscript</code>, <code>myscript</code>,
- <code>postmyscript</code>). Scripts from dependencies can be run with <code>npm explore
- <pkg> -- npm run <stage></code>.</p>
- <h2 id="prepublish-and-prepare">PREPUBLISH AND PREPARE</h2>
- <h3 id="deprecation-note">DEPRECATION NOTE</h3>
- <p>Since <a href="mailto:%60npm@1.1.71">`npm@1.1.71</a><code>, the npm CLI has run the</code>prepublish<code>script for both</code>npm
- publish<code>and</code>npm install<code>, because it's a convenient way to prepare a package
- for use (some common use cases are described in the section below). It has
- also turned out to be, in practice, [very
- confusing](https://github.com/npm/npm/issues/10074). As of</code><a href="mailto:npm@4.0.0">npm@4.0.0</a><code>, a new
- event has been introduced,</code>prepare<code>, that preserves this existing behavior. A
- _new_ event,</code>prepublishOnly<code>has been added as a transitional strategy to
- allow users to avoid the confusing behavior of existing npm versions and only
- run on</code>npm publish` (for instance, running the tests one last time to ensure
- they're in good shape).</p>
- <p>See <a href="https://github.com/npm/npm/issues/10074">https://github.com/npm/npm/issues/10074</a> for a much lengthier
- justification, with further reading, for this change.</p>
- <h3 id="use-cases">USE CASES</h3>
- <p>If you need to perform operations on your package before it is used, in a way
- that is not dependent on the operating system or architecture of the
- target system, use a <code>prepublish</code> script. This includes
- tasks such as:</p>
- <ul>
- <li>Compiling CoffeeScript source code into JavaScript.</li>
- <li>Creating minified versions of JavaScript source code.</li>
- <li>Fetching remote resources that your package will use.</li>
- </ul>
- <p>The advantage of doing these things at <code>prepublish</code> time is that they can be done once, in a
- single place, thus reducing complexity and variability.
- Additionally, this means that:</p>
- <ul>
- <li>You can depend on <code>coffee-script</code> as a <code>devDependency</code>, and thus
- your users don't need to have it installed.</li>
- <li>You don't need to include minifiers in your package, reducing
- the size for your users.</li>
- <li>You don't need to rely on your users having <code>curl</code> or <code>wget</code> or
- other system tools on the target machines.</li>
- </ul>
- <h2 id="default-values">DEFAULT VALUES</h2>
- <p>npm will default some script values based on package contents.</p>
- <ul>
- <li><p><code>"start": "node server.js"</code>:</p>
- <p>If there is a <code>server.js</code> file in the root of your package, then npm
- will default the <code>start</code> command to <code>node server.js</code>.</p>
- </li>
- <li><p><code>"install": "node-gyp rebuild"</code>:</p>
- <p>If there is a <code>binding.gyp</code> file in the root of your package and you
- haven't defined your own <code>install</code> or <code>preinstall</code> scripts, npm will
- default the <code>install</code> command to compile using node-gyp.</p>
- </li>
- </ul>
- <h2 id="user">USER</h2>
- <p>If npm was invoked with root privileges, then it will change the uid
- to the user account or uid specified by the <code>user</code> config, which
- defaults to <code>nobody</code>. Set the <code>unsafe-perm</code> flag to run scripts with
- root privileges.</p>
- <h2 id="environment">ENVIRONMENT</h2>
- <p>Package scripts run in an environment where many pieces of information
- are made available regarding the setup of npm and the current state of
- the process.</p>
- <h3 id="path">path</h3>
- <p>If you depend on modules that define executable scripts, like test
- suites, then those executables will be added to the <code>PATH</code> for
- executing the scripts. So, if your package.json has this:</p>
- <pre><code>{ "name" : "foo"
- , "dependencies" : { "bar" : "0.1.x" }
- , "scripts": { "start" : "bar ./test" } }</code></pre><p>then you could run <code>npm start</code> to execute the <code>bar</code> script, which is
- exported into the <code>node_modules/.bin</code> directory on <code>npm install</code>.</p>
- <h3 id="package-json-vars">package.json vars</h3>
- <p>The package.json fields are tacked onto the <code>npm_package_</code> prefix. So,
- for instance, if you had <code>{"name":"foo", "version":"1.2.5"}</code> in your
- package.json file, then your package scripts would have the
- <code>npm_package_name</code> environment variable set to "foo", and the
- <code>npm_package_version</code> set to "1.2.5". You can access these variables
- in your code with <code>process.env.npm_package_name</code> and
- <code>process.env.npm_package_version</code>, and so on for other fields.</p>
- <h3 id="configuration">configuration</h3>
- <p>Configuration parameters are put in the environment with the
- <code>npm_config_</code> prefix. For instance, you can view the effective <code>root</code>
- config by checking the <code>npm_config_root</code> environment variable.</p>
- <h3 id="special-package-json-config-object">Special: package.json "config" object</h3>
- <p>The package.json "config" keys are overwritten in the environment if
- there is a config param of <code><name>[@<version>]:<key></code>. For example,
- if the package.json has this:</p>
- <pre><code>{ "name" : "foo"
- , "config" : { "port" : "8080" }
- , "scripts" : { "start" : "node server.js" } }</code></pre><p>and the server.js is this:</p>
- <pre><code>http.createServer(...).listen(process.env.npm_package_config_port)</code></pre><p>then the user could change the behavior by doing:</p>
- <pre><code>npm config set foo:port 80</code></pre><h3 id="current-lifecycle-event">current lifecycle event</h3>
- <p>Lastly, the <code>npm_lifecycle_event</code> environment variable is set to
- whichever stage of the cycle is being executed. So, you could have a
- single script used for different parts of the process which switches
- based on what's currently happening.</p>
- <p>Objects are flattened following this format, so if you had
- <code>{"scripts":{"install":"foo.js"}}</code> in your package.json, then you'd
- see this in the script:</p>
- <pre><code>process.env.npm_package_scripts_install === "foo.js"</code></pre><h2 id="examples">EXAMPLES</h2>
- <p>For example, if your package.json contains this:</p>
- <pre><code>{ "scripts" :
- { "install" : "scripts/install.js"
- , "postinstall" : "scripts/install.js"
- , "uninstall" : "scripts/uninstall.js"
- }
- }</code></pre><p>then <code>scripts/install.js</code> will be called for the install
- and post-install stages of the lifecycle, and <code>scripts/uninstall.js</code>
- will be called when the package is uninstalled. Since
- <code>scripts/install.js</code> is running for two different phases, it would
- be wise in this case to look at the <code>npm_lifecycle_event</code> environment
- variable.</p>
- <p>If you want to run a make command, you can do so. This works just
- fine:</p>
- <pre><code>{ "scripts" :
- { "preinstall" : "./configure"
- , "install" : "make && make install"
- , "test" : "make test"
- }
- }</code></pre><h2 id="exiting">EXITING</h2>
- <p>Scripts are run by passing the line as a script argument to <code>sh</code>.</p>
- <p>If the script exits with a code other than 0, then this will abort the
- process.</p>
- <p>Note that these script files don't have to be nodejs or even
- javascript programs. They just have to be some kind of executable
- file.</p>
- <h2 id="hook-scripts">HOOK SCRIPTS</h2>
- <p>If you want to run a specific script at a specific lifecycle event for
- ALL packages, then you can use a hook script.</p>
- <p>Place an executable file at <code>node_modules/.hooks/{eventname}</code>, and
- it'll get run for all packages when they are going through that point
- in the package lifecycle for any packages installed in that root.</p>
- <p>Hook scripts are run exactly the same way as package.json scripts.
- That is, they are in a separate child process, with the env described
- above.</p>
- <h2 id="best-practices">BEST PRACTICES</h2>
- <ul>
- <li>Don't exit with a non-zero error code unless you <em>really</em> mean it.
- Except for uninstall scripts, this will cause the npm action to
- fail, and potentially be rolled back. If the failure is minor or
- only will prevent some optional features, then it's better to just
- print a warning and exit successfully.</li>
- <li>Try not to use scripts to do what npm can do for you. Read through
- <code><a href="../files/package.json.html">package.json(5)</a></code> to see all the things that you can specify and enable
- by simply describing your package appropriately. In general, this
- will lead to a more robust and consistent state.</li>
- <li>Inspect the env to determine where to put things. For instance, if
- the <code>npm_config_binroot</code> environment variable is set to <code>/home/user/bin</code>, then
- don't try to install executables into <code>/usr/local/bin</code>. The user
- probably set it up that way for a reason.</li>
- <li>Don't prefix your script commands with "sudo". If root permissions
- are required for some reason, then it'll fail with that error, and
- the user will sudo the npm command in question.</li>
- <li>Don't use <code>install</code>. Use a <code>.gyp</code> file for compilation, and <code>prepublish</code>
- for anything else. You should almost never have to explicitly set a
- preinstall or install script. If you are doing this, please consider if
- there is another option. The only valid use of <code>install</code> or <code>preinstall</code>
- scripts is for compilation which must be done on the target architecture.</li>
- </ul>
- <h2 id="see-also">SEE ALSO</h2>
- <ul>
- <li><a href="../cli/npm-run-script.html">npm-run-script(1)</a></li>
- <li><a href="../files/package.json.html">package.json(5)</a></li>
- <li><a href="../misc/npm-developers.html">npm-developers(7)</a></li>
- <li><a href="../cli/npm-install.html">npm-install(1)</a></li>
- </ul>
-
- </div>
-
- <table border=0 cellspacing=0 cellpadding=0 id=npmlogo>
- <tr><td style="width:180px;height:10px;background:rgb(237,127,127)" colspan=18> </td></tr>
- <tr><td rowspan=4 style="width:10px;height:10px;background:rgb(237,127,127)"> </td><td style="width:40px;height:10px;background:#fff" colspan=4> </td><td style="width:10px;height:10px;background:rgb(237,127,127)" rowspan=4> </td><td style="width:40px;height:10px;background:#fff" colspan=4> </td><td rowspan=4 style="width:10px;height:10px;background:rgb(237,127,127)"> </td><td colspan=6 style="width:60px;height:10px;background:#fff"> </td><td style="width:10px;height:10px;background:rgb(237,127,127)" rowspan=4> </td></tr>
- <tr><td colspan=2 style="width:20px;height:30px;background:#fff" rowspan=3> </td><td style="width:10px;height:10px;background:rgb(237,127,127)" rowspan=3> </td><td style="width:10px;height:10px;background:#fff" rowspan=3> </td><td style="width:20px;height:10px;background:#fff" rowspan=4 colspan=2> </td><td style="width:10px;height:20px;background:rgb(237,127,127)" rowspan=2> </td><td style="width:10px;height:10px;background:#fff" rowspan=3> </td><td style="width:20px;height:10px;background:#fff" rowspan=3 colspan=2> </td><td style="width:10px;height:10px;background:rgb(237,127,127)" rowspan=3> </td><td style="width:10px;height:10px;background:#fff" rowspan=3> </td><td style="width:10px;height:10px;background:rgb(237,127,127)" rowspan=3> </td></tr>
- <tr><td style="width:10px;height:10px;background:#fff" rowspan=2> </td></tr>
- <tr><td style="width:10px;height:10px;background:#fff"> </td></tr>
- <tr><td style="width:60px;height:10px;background:rgb(237,127,127)" colspan=6> </td><td colspan=10 style="width:10px;height:10px;background:rgb(237,127,127)"> </td></tr>
- <tr><td colspan=5 style="width:50px;height:10px;background:#fff"> </td><td style="width:40px;height:10px;background:rgb(237,127,127)" colspan=4> </td><td style="width:90px;height:10px;background:#fff" colspan=9> </td></tr>
- </table>
- <p id="footer">npm-scripts — npm@6.4.1</p>
-
|
