Job Template Examples and Extensions

Use this section as a reference to help modify, customize, and extend your job templates to suit your requirements.

Customizing Job Templates

When creating a job template, you can include an existing template in the template editor field. This way you can combine templates, or create more specific templates from the general ones.

The following template combines default templates to install and start the nginx service on clients:

<%= render_template 'Package Action - SSH Default', :action => 'install', :package => 'nginx' %>
<%= render_template 'Service Action - SSH Default', :action => 'start', :service_name => 'nginx' %>

The above template specifies parameter values for the rendered template directly. It is also possible to use the input() method to allow users to define input for the rendered template on job execution. For example, you can use the following syntax:

<%= render_template 'Package Action - SSH Default', :action => 'install', :package => input("package") %>

With the above template, you have to import the parameter definition from the rendered template. To do so, navigate to the Jobs tab, click Add Foreign Input Set, and select the rendered template from the Target template list. You can import all parameters or specify a comma separated list.

Default Job Template Categories

Job template category	Description
Packages	Templates for performing package related actions. Install, update, and remove actions are included by default.
Puppet	Templates for executing Puppet runs on target hosts.
Power	Templates for performing power related actions. Restart and shutdown actions are included by default.
Commands	Templates for executing custom commands on remote hosts.
Services	Templates for performing service related actions. Start, stop, restart, and status actions are included by default.
Katello	Templates for performing content related actions. These templates are used mainly from different parts of the orcharhino management UI (for example bulk actions UI for content hosts), but can be used separately to perform operations such as errata installation.

Job template category

Description

Packages

Templates for performing package related actions. Install, update, and remove actions are included by default.

Puppet

Templates for executing Puppet runs on target hosts.

Power

Templates for performing power related actions. Restart and shutdown actions are included by default.

Commands

Templates for executing custom commands on remote hosts.

Services

Templates for performing service related actions. Start, stop, restart, and status actions are included by default.

Katello

Templates for performing content related actions. These templates are used mainly from different parts of the orcharhino management UI (for example bulk actions UI for content hosts), but can be used separately to perform operations such as errata installation.

Example restorecon Template

This example shows how to create a template called Run Command - restorecon that restores the default SELinux context for all files in the selected directory on target hosts.

Procedure

In the orcharhino management UI, navigate to Hosts > Job templates.
Click New Job Template.
Enter Run Command - restorecon in the Name field. Select Default to make the template available to all organizations. Add the following text to the template editor:
```
restorecon -RvF <%= input("directory") %>
```
The <%= input("directory") %> string is replaced by a user-defined directory during job invocation.
On the Job tab, set Job category to Commands.
Click Add Input to allow job customization. Enter directory to the Name field. The input name must match the value specified in the template editor.
Click Required so that the command cannot be executed without the user specified parameter.
Select User input from the Input type list. Enter a description to be shown during job invocation, for example Target directory for restorecon.
Click Submit. For more information, see Executing a restorecon Template on Multiple Hosts in Managing Hosts.

Rendering a restorecon Template

This example shows how to create a template derived from the Run command - restorecon template created in Example restorecon Template. This template does not require user input on job execution, it will restore the SELinux context in all files under the /home/ directory on target hosts.

Create a new template as described in Setting up Job Templates, and specify the following string in the template editor:

<%= render_template("Run Command - restorecon", :directory => "/home") %>

Executing a restorecon Template on Multiple Hosts

This example shows how to run a job based on the template created in Example restorecon Template on multiple hosts. The job restores the SELinux context in all files under the /home/ directory.

Procedure

In the orcharhino management UI, navigate to Monitor > Jobs and click Run job.
Select Commands as Job category and Run Command – restorecon as Job template and click Next.
Select the hosts on which you want to run the job. If you do not select any hosts, the job will run on all hosts you can see in the current context.
In the directory field, provide a directory, for example /home, and click Next.
Optional: To configure advanced settings for the job, fill in the Advanced fields. To learn more about advanced settings, see advanced settings in the job wizard. When you are done entering the advanced settings or if it is not required, click Next.
Schedule time for the job.
- To execute the job immediately, keep the pre-selected Immediate execution.
- To execute the job in future time, select Future execution.
- To execute the job on regular basis, select Recurring execution.
Optional: If you selected future or recurring execution, select the Query type, otherwise click Next.
- Static query means that the job executes on the exact list of hosts that you provided.
- Dynamic query means that the list of hosts is evaluated just before the job is executed. If you entered the list of hosts based on some filter, the results can be different from when you first used that filter.
  
  Click Next after you have selected the query type.
Optional: If you selected future or recurring execution, provide additional details:
- For Future execution, enter the Starts at date and time. You also have the option to select the Starts before date and time. If the job cannot start before that time, it will be canceled.
- For Recurring execution, select the start date and time, frequency, and condition for ending the recurring job. You can choose the recurrence to never end, end at a certain time, or end after a given number of repetitions. You can also add Purpose - a special label for tracking the job. There can only be one active job with a given purpose at a time.
  
  Click Next after you have entered the required information.
Review job details. You have the option to return to any part of the job wizard and edit the information.
Click Submit to schedule the job for execution.

Including Power Actions in Templates

This example shows how to set up a job template for performing power actions, such as reboot. This procedure prevents orcharhino from interpreting the disconnect exception upon reboot as an error, and consequently, remote execution of the job works correctly.

Create a new template as described in Setting up Job Templates, and specify the following string in the template editor:

<%= render_template("Power Action - SSH Default", :action => "restart") %>

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