Use a Local Static List

The simplest customization can be done by defining a static list of queues/partitions within the Interactive App that a user can submit the batch job to. This is accomplished by:

1. Add Custom Attribute to Form

2. Handle Custom Attribute in Job Submission

Add Custom Attribute to Form

We want to replace the bc_queue form attribute with a custom HTML <select> element (a drop-down list of options).

Note

You can read more about customizing attributes in the form.yml file for Interactive Apps under the Customizing Attributes section.

1. We first start with the default form.yml for the Jupyter Interactive App:

   # ~/ondemand/dev/jupyter/form.yml
   ---
   cluster: "my_cluster"
   attributes:
     modules: "python"
     extra_jupyter_args: ""
   form:
     - modules
     - extra_jupyter_args
     - bc_account
     - bc_queue
     - bc_num_hours
     - bc_num_slots
     - bc_email_on_started
   

2. Next we remove the bc_queue field from our form.yml for the Jupyter Interactive App by removing the following line from this file:

   - bc_account
   - bc_queue
   - bc_num_hours
   

   Now when we refresh the web page for our sandbox Jupyter App we won’t see the “Queue” form element anymore.

3. We now add in our custom drop-down attribute with a defined list of queues/partitions:

   # ~/ondemand/dev/jupyter/form.yml
   ---
   cluster: "my_cluster"
   attributes:
     modules: "python"
     extra_jupyter_args: ""
     custom_queue:
       label: Queue
       help: Please select a queue from the drop-down.
       widget: select
       options:
         - [ "Queue 1", "queue1" ]
         - [ "Queue 2", "queue2" ]
   form:
     - modules
     - extra_jupyter_args
     - bc_account
     - custom_queue
     - bc_num_hours
     - bc_num_slots
     - bc_email_on_started
   

   Now when we refresh the web page for our sandbox Jupyter App we will see a “Queue” form element with a drop-down that lists “queue1” and “queue2”. Underneath this will be our custom help message defined above.

   Note

   An attribute with the field widget: select expects an options: field with an array of pairs. The first string in the pair is the option text and the second string in the pair is the option value.

   For example:

   widget: select
   options:
     - [ "Volvo", "volvo" ]
     - [ "Ford", "ford" ]
     - [ "Toyota", "toyota" ]
   

   The user will see a list of options: “Volvo”, “Ford”, and “Toyota” to choose from in the HTML form, but the backend will process a value of either “volvo”, “ford”, or “toyota” depending on what the user chose.

Handle Custom Attribute in Job Submission

Now that we have our custom form attribute called custom_queue, we need to tell our app how to handle it when submitting the job. As of right now our app has no idea what to do with this value when the user clicks “Launch” after filling out the form.

Note

You can read more about customizing submission arguments in the submit.yml.erb file for Interactive Apps under the Job Submission (submit.yml.erb) section.

1. We first start with the default submit.yml.erb for the Jupyter Interactive App:

   # ~/ondemand/dev/jupyter/submit.yml.erb
   ---
   batch_connect:
     template: "basic"
   

2. We now create a script: section if it doesn’t already exist and handle the value of the custom_queue attribute submitted by the user:

   # ~/ondemand/dev/jupyter/submit.yml.erb
   ---
   batch_connect:
     template: "basic"
   script:
     queue_name: <%= custom_queue %>
   

   Where we take advantage of the generic OodCore::Job::Script#queue_name method to supply a queue/partition that is resource manager (e.g., Slurm, Torque, …) agnostic.

   Note

   For the queue/partition we do not need to use the native: field which must be customized for the specific resource manager you are leveraging.

   You can find a list of generic fields that are resource manager agnostic under the OodCore::Job::Script documentation.