[Hawkular-dev] you can now download a wildfly agent installer from kettle

[John Mazzitelli]

Jirka put together a small UI and enhanced the download servlet, which I then went in and enhanced further, so you can now get a wildfly agent installer.

Here's quickly how it should work:

1) Go to the UI and fill in the fields, submit it, and you should be able to save the installer jar you get back
1b) alternatively, you can download it from the command line like this:
   wget --content-disposition 'http://localhost:8080/wildfly-agent/download?installer=true

at this point, you have something like "hawkular-wildfly-agent-installer-0.13.1.Final.jar" on your file system.

2) Run the installer jar, pointing it to the wildfly you want to install it to:

java -jar hawkular-wildfly-agent-installer-0.13.1.Final.jar --wildfly-home=/path/to/your/wildfly/home

This installs the agent to your wildfly server.

That should be it. Run your wildfly and you've got it monitored by the agent.

Now, of course, there are lots of ways you can customize the agent installation. The above just gets you the default agent with jdoe/password credentials assuming http://localhost:8080 is accessible when you install.

Whatever properties that are accepted in the installer .properties file (which are also the same cmdline options to the installer) you can pass to the download URL so they can be preset for you in the installer's default configuration. So, for example, if you want all of your agents to talk to "http://your-hawk-server:8080", you can do this to get an installer that will install an agent talking to that server:

   wget --content-disposition 'http://localhost:8080/wildfly-agent/download?installer=true&hawkular-server-url=http://your-hawk-server:8080'

There are other properties you can pass in if you want to further customize the installer and the agent it installs. Just look at this for all that are available:

https://github.com/hawkular/hawkular-agent/blob/master/hawkular-wildfly-agent-installer/src/main/resources/hawkular-wildfly-agent-installer.properties

In the future, we want to have the installer that you download preconfigured (if you want) for the credentials of the user who requested the download, and preconfigured for the server that you downloaded the installer from (right now, it defaults to "http://localhost:8080" which is not optimal). But, again, you can customize this now via installer cmdline options if you want:

java -jar hawkular-wildfly-agent-installer-0.13.1.Final.jar \
    --wildfly-home=/path/to/your/wildfly/home \
    --hawkular-server-url=http://your-server:8080 \
    --hawkular-security-key=your-offline-token-key \
    --hawkular-security-secret=your-offline-token-secret \
    --subsystem-snippet=/path/to/my/custom/agent-subsystem.xml

That latter one (subsystem-snippet) is a powerful way you can further configure the agent by giving a full .xml of the agent subsystem (so you can do things like define what resource-type-dmr definitions you want, what metrics you want enabled or disabled, etc, etc.)