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[[configuring-fastcgi]]
=== Configuring Jetty for FastCGI

In this section you will see how to configure Jetty to serve WordPress via FastCGI.

The first step is to have WordPress installed on your server machine, for example under `/var/www/wordpress`.
For more information about how to install WordPress, please refer to the https://codex.wordpress.org/Installing_WordPress[WordPress Installation Guide].

The second step is to install `php-fpm` and make sure it is configured to listen on a TCP socket; typically it is configured to listen to `localhost:9000`.

The third step is to install Jetty, for example under `/opt/jetty`, called in the following `$JETTY_HOME`.
Refer to xref:jetty-downloading[] for more information about how to install Jetty.

The fourth step is to create a Jetty base directory (see xref:startup-base-and-home[]), called in the following `$JETTY_BASE`, where you setup the configuration needed to support FastCGI in Jetty, and configure the `fcgi`, `http` and `deploy` modules, so that Jetty will be able to accept HTTP requests from browsers, convert them in FastCGI, and proxy them to `php-fpm`:

[source, screen, subs="{sub-order}"]
....
$ mkdir -p /usr/jetty/wordpress
$ cd /usr/jetty/wordpress
$ java -jar $JETTY_HOME/start.jar --add-to-start=fcgi,http,deploy
....

Therefore `$JETTY_BASE=/usr/jetty/wordpress`.

The fifth step is to deploy the web application that provides the proxying of client requests to the FastCGI server, `php-fpm`.
Typically this is done by deploying a `*.war` file in the `$JETTY_BASE/webapps` directory.
For FastCGI there is no web application that needs developed - all the work has already been done for you by Jetty.
As such you only need to deploy a Jetty context XML file that configures the web application directly.
Copy and paste the following content as `$JETTY_BASE/webapps/jetty-wordpress.xml`:

[source, xml, subs="{sub-order}"]
----
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE Configure PUBLIC "-//Jetty//Configure//EN" "https://www.eclipse.org/jetty/configure_9_3.dtd">
<Configure class="org.eclipse.jetty.servlet.ServletContextHandler">

    <New id="root" class="java.lang.String">
        <Arg>/var/www/wordpress</Arg>
    </New>

    <Set name="contextPath">/</Set>
    <Set name="resourceBase"><Ref refid="root" /></Set>
    <Set name="welcomeFiles">
        <Array type="string"><Item>index.php</Item></Array>
    </Set>

    <Call name="addFilter">
        <Arg>org.eclipse.jetty.fcgi.server.proxy.TryFilesFilter</Arg>
        <Arg>/*</Arg>
        <Arg>
            <Call name="of" class="java.util.EnumSet">
                <Arg><Get name="REQUEST" class="javax.servlet.DispatcherType" /></Arg>
            </Call>
        </Arg>
        <Call name="setInitParameter">
            <Arg>files</Arg>
            <Arg>$path /index.php?p=$path</Arg>
        </Call>
    </Call>

    <Call name="addServlet">
        <Arg>
            <New class="org.eclipse.jetty.servlet.ServletHolder">
                <Arg>default</Arg>
                <Arg>
                    <Call name="forName" class="java.lang.Class">
                        <Arg>org.eclipse.jetty.servlet.DefaultServlet</Arg>
                    </Call>
                </Arg>
                <Call name="setInitParameter">
                    <Arg>dirAllowed</Arg>
                    <Arg>false</Arg>
                </Call>
            </New>
        </Arg>
        <Arg>/</Arg>
    </Call>

    <Call name="addServlet">
        <Arg>org.eclipse.jetty.fcgi.server.proxy.FastCGIProxyServlet</Arg>
        <Arg>*.php</Arg>
        <Call name="setInitParameter">
            <Arg>proxyTo</Arg>
            <Arg>http://localhost:9000</Arg>
        </Call>
        <Call name="setInitParameter">
            <Arg>prefix</Arg>
            <Arg>/</Arg>
        </Call>
        <Call name="setInitParameter">
            <Arg>scriptRoot</Arg>
            <Arg><Ref refid="root" /></Arg>
        </Call>
        <Call name="setInitParameter">
            <Arg>scriptPattern</Arg>
            <Arg>(.+?\\.php)</Arg>
        </Call>
    </Call>

</Configure>

----

An explanation of the above contents:

* Linne 6 specifies the WordPress installation directory, in this example `/var/www/wordpress` (as defined in the first step).
* Line 9 it is specified the context path at which WordPress will be served, in this example at the root context path `/`.
* Line 10 specifies the resource base of the context, also set to the WordPress installation directory.
This allows Jetty to serve static resources directly from the WordPress installation directory.
* Line 12 specifies the welcome file as `index.php`, so that Jetty can perform the proper redirects in case of URIs ending with the `/` character.
* Line 15 specifies the `TryFilesFilter`, a Servlet Filter that has been inspired by the http://wiki.nginx.org/HttpCoreModule#try_files[try_files] functionality offered by Nginx.
This filter tries to serve the resource from the file system first, and if the resource is not found it forwards the request as `index.php?p=$path`, which will match the proxy servlet defined below.
Refer to the link:{JDURL}/org/eclipse/jetty/fcgi/server/proxy/TryFilesFilter.html[TryFilesFilter] documentation for further information.
* Line 29specifies Jetty's `DefaultServlet` to serve static content such as CSS files, JavaScript files, etc. `DefaultServlet` will serve these files by looking in the resource base of the context, defined at line 10 (see above).
* Line 47 specifies the `FastCGIProxyServlet`, a Servlet that proxies HTTP requests arriving from clients to FastCGI requests to the FastCGI server.
* Line 52 specifies the TCP address of the FastCGI server (`php-fpm`), where HTTP requests are forwarded as FastCGI requests.
* Line 60 specifies once again the WordPress installation directory, so that the `FastCGIProxyServlet` can pass this information to the FastCGI server.
* Line 64 specifies a regular expression that matches request URIs performed to this servlet, in addition to the standard URL mapping defined by Servlet at line 49.
Refer to the link:{JDURL}/org/eclipse/jetty/fcgi/server/proxy/FastCGIProxyServlet.html[FastCGIProxyServlet] documentation for further information.

The last step is to start Jetty (see xref:startup[]) and navigate to `http://localhost:8080` with your browser and enjoy WordPress:

[source, screen, subs="{sub-order}"]
....
$ cd $JETTY_BASE
$ java -jar /opt/jetty/start.jar
....

[[configuring-fastcgi-http2]]
==== Configuring Jetty to Proxy HTTP/2 to FastCGI

In order to configure Jetty to listen for HTTP/2 requests from clients that are HTTP/2 enabled and forward them to the FastCGI server as FastCGI requests, you need to enable the `http2` module, which in turn will require a TLS connector and consequently a keystore to read the key material required by TLS.

Enabling the `http2` is easy; in additions to the modules you have enabled above, add the `http2` module:

[source, screen, subs="{sub-order}"]
....
$ cd $JETTY_BASE
$ java -jar $JETTY_HOME/start.jar --add-to-start=http2
....

The command above adds the `http2` module (and its dependencies) to the existing modules and uses the default Jetty keystore to provide the key material required by TLS.
You will want to use your own keystore with your own private key and certificate for your own domain.

Remember that by adding the `http2` module, you will start two JVMs: one that reads the configuration, and one that has the ALPN boot boot jar in the boot classpath, as explained in xref:http2-configuring[].

Since now your site will run over TLS, you need to make sure that the WordPress URL is also configured so.
If you have followed the steps of the link:#configuring-fastcgi[previous section], your WordPress site is served at `http://localhost:8080`.
You will need to change that to be `https://localhost:8443` from the WordPress administration web interface, or follow the http://codex.wordpress.org/Changing_The_Site_URL[WordPress instructions] to do so without using the administration web interface.

The minimal modules required to run WordPress with Jetty on HTTP/2 are therefore: `http2`, `http`, `fcgi` and `deploy`.
These will setup a clear text connector on port 8080 for HTTP/1.1 and a TLS connector on port 8443 for HTTP/2 and HTTP/1.1.

At this point, you can start Jetty (see xref:startup[]), hit `http://localhost:8080` with your browser and enjoy WordPress via HTTP/2 using a HTTP/2 enabled browser:

[source, screen, subs="{sub-order}"]
....
$ cd $JETTY_BASE
$ java -jar $JETTY_HOME/start.jar
....

If you don't have a HTTP/2 enabled browser, WordPress will still be available over HTTP/1.1.
