Mercurial > hg > nginx-site
view xml/en/docs/stream/ngx_stream_js_module.xml @ 1879:3685d90e133e
Documented the "absolute_redirect" directive.
author | Yaroslav Zhuravlev <yar@nginx.com> |
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date | Mon, 26 Dec 2016 23:25:26 +0300 |
parents | 621daf1b77d0 |
children | b93b0689f13b |
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<?xml version="1.0"?> <!-- Copyright (C) Nginx, Inc. --> <!DOCTYPE module SYSTEM "../../../../dtd/module.dtd"> <module name="Module ngx_stream_js_module" link="/en/docs/stream/ngx_stream_js_module.html" lang="en" rev="5"> <section id="summary"> <para> The <literal>ngx_stream_js_module</literal> module is used to implement handlers in <link doc="../njs_about.xml">nginScript</link> — a subset of the JavaScript language. </para> <para> This module is not built by default, it should be compiled with the nginScript module using the <literal>--add_module</literal> configuration parameter: <example> ./configure --add-module=<value>path-to-njs</value>/nginx </example> The <link url="http://hg.nginx.org/njs">repository</link> with the nginScript module can be cloned with the following command (requires <link url="https://www.mercurial-scm.org">Mercurial</link> client): <example> hg clone http://hg.nginx.org/njs </example> This module can also be built as <link doc="../ngx_core_module.xml" id="load_module">dynamic</link>: <example> ./configure --add-dynamic_module=<value>path-to-njs</value>/nginx </example> </para> </section> <section id="issues" name="Known Issues"> <para> The module is experimental, caveat emptor applies. </para> </section> <section id="example" name="Example Configuration"> <para> <example> stream { js_include stream.js; js_set $foo foo; js_set $bar bar; server { listen 12345; js_preread qux; return foo; } server { listen 12346; js_access xyz; proxy_pass 127.0.0.1:8000; js_filter baz; } } http { server { listen 8000; location / { return 200 $http_foo\n; } } } </example> </para> <para> The <path>stream.js</path> file: <example> var req = ''; var matched = 0; var line = ''; function qux(s) { n = s.buffer.indexOf('\n'); if (n == -1) { return s.AGAIN; } line = s.buffer.substr(0, n); } function foo(s) { return line; } function bar(s) { var v = s.variables; s.log("hello from bar() handler!"); return "foo-var" + v.remote_port + "; pid=" + v.pid; } // The filter processes one buffer per call. // The buffer is available in s.buffer both for // reading and writing. Called for both directions. function baz(s) { if (s.fromUpstream || matched) { return; } // Disable certain addresses. if (s.remoteAddress.match('^192.*')) { return s.ERROR; } // Read HTTP request line. // Collect bytes in 'req' until request // line is read. Clear current buffer to // disable output. req = req + s.buffer; s.buffer = ''; n = req.search('\n'); if (n != -1) { // Inject a new HTTP header. var rest = req.substr(n + 1); req = req.substr(0, n + 1); addr = s.remoteAddress; s.log('req:' + req); s.log('rest:' + rest); // Output the result and skip further // processing. s.buffer = req + 'Foo: addr_' + addr + '\r\n' + rest; matched = 1; } } function xyz(s) { if (s.remoteAddress.match('^192.*')) { return s.ABORT; } } </example> </para> </section> <section id="directives" name="Directives"> <directive name="js_access"> <syntax><value>function</value></syntax> <default/> <context>stream</context> <context>server</context> <para> Sets an nginScript function which will be called at the <link doc="stream_processing.xml" id="access_phase">access</link> phase. </para> </directive> <directive name="js_filter"> <syntax><value>function</value></syntax> <default/> <context>stream</context> <context>server</context> <para> Sets a data filter. </para> </directive> <directive name="js_include"> <syntax><value>file</value></syntax> <default/> <context>stream</context> <para> Specifies a file that implements server and variable handlers in nginScript. </para> </directive> <directive name="js_preread"> <syntax><value>function</value></syntax> <default/> <context>stream</context> <context>server</context> <para> Sets an nginScript function which will be called at the <link doc="stream_processing.xml" id="preread_phase">preread</link> phase. </para> </directive> <directive name="js_set"> <syntax> <value>$variable</value> <value>function</value></syntax> <default/> <context>stream</context> <para> Sets an nginScript function for the specified variable. </para> </directive> </section> <section id="properties" name="Session Object Properties"> <para> Each stream nginScript handler receives one argument, a stream session object. </para> <para> The session object has the following properties: <list type="tag"> <tag-name><literal>remoteAddress</literal></tag-name> <tag-desc> client address, read-only </tag-desc> <tag-name><literal>eof</literal></tag-name> <tag-desc> a boolean read-only property, true if the current buffer is the last buffer </tag-desc> <tag-name><literal>fromUpstream</literal></tag-name> <tag-desc> a boolean read-only property, true if the current buffer is from the upstream server to the client </tag-desc> <tag-name><literal>buffer</literal></tag-name> <tag-desc> the current buffer, writable </tag-desc> <tag-name><literal>variables{}</literal></tag-name> <tag-desc> nginx variables object, read-only </tag-desc> <tag-name><literal>OK</literal></tag-name> <tag-desc> the <literal>OK</literal> return code </tag-desc> <tag-name><literal>DECLINED</literal></tag-name> <tag-desc> the <literal>DECLINED</literal> return code </tag-desc> <tag-name><literal>AGAIN</literal></tag-name> <tag-desc> the <literal>AGAIN</literal> return code </tag-desc> <tag-name><literal>ERROR</literal></tag-name> <tag-desc> the <literal>ERROR</literal> return code </tag-desc> <tag-name><literal>ABORT</literal></tag-name> <tag-desc> the <literal>ABORT</literal> return code </tag-desc> </list> </para> <para> The session object has the following methods: <list type="tag"> <tag-name><literal>log(<value>string</value>)</literal></tag-name> <tag-desc> writes a sent <value>string</value> to the error log </tag-desc> </list> </para> </section> </module>