Getting Your First Workflow

We can use the Workflow Catalog to get up and running quickly with a basic Fuzzball example. The Workflow Catalog has templates that create Fuzzfiles automatically from a workflow template and user-provided parameters. In this tutorial, we will use the Printer template to create a Fuzzfile and run a simple workflow.

In the Workflow Catalog use the search bar to locate the example named “Printer Example”.

You can see details about the workflow template by either clicking on the name of the workflow or by selecting “View details” from the kebab menu of the workflow template card. The detail page will show you a template used to create the printer workflow Fuzzfile, as well as the inputs that can be changed by the user. The values in the YAML template that are surrounded by double curly braces and preceded by a dot (e.g. {{.Container}}) are inputs that you can change before rendering the finished Fuzzfile.

You can choose to render the workflow template with the parameters you select and open the resulting Fuzzfile in the Workflow Editor (“Render Fuzzfile and Edit”), or directly run it (“Render Fuzzfile and Run”). For the purposes of this tutorial, select “Render Fuzzfile and Run”. Either way, a dialog box like the following will open allowing you to edit the input parameters before creating the final Fuzzfile.

The printer template allows you to change the container that is used to run the printer job, and the number of seconds that the job runs. Other templates may allow you to change the commands that are run, the resources that are used, etc.

For now, just select “Run” without changing any defaults. The message at the bottom indicates that the Fuzzfile has been automatically rendered (behind the scenes) and checked for valid syntax and you are presented with a dialog showing a summary of the rendered workflow and allowing you to name your workflow execution.

That’s it! At this point a valid Fuzzfile for the printer workflow has been saved behind the scenes and is ready to be submitted by clicking the “Start Workflow” button. We’ll look at submitting the workflow in the next section on Starting and Stopping Your New Workflow.

Building your Fuzzfile outside of the GUI is simply a matter of using a text editor. First, let’s create a new directory to experiment in:

$ mkdir ~/fb-work

$ cd !$

Now either copy and paste the contents of printer.fz described here into the appropriately named file using the text editor of your choice, or download the file and place it in the directory you just created.

version: v1
jobs:
  printer:
      #!/bin/sh
      uri: docker://docker.io/alpine:latest
    policy:
      timeout:
        execute: 6m0s
    script: |
      #!/bin/sh
      for i in $(seq 1 300); do echo $i; sleep 1; done
    resource:
      cpu:
        cores: 1
      memory:
        size: 1GB

The .fz file extension is not necessary. Fuzzfiles also commonly carry .yml or .yaml extensions since they are written in YAML.

Fuzzball will automatically check and validate your Fuzzfile for syntax errors when you submit the workflow, but you can do so manually with the following command:

$ fuzzball workflow validate ./printer.fz
"./printer.fz" has been validated.

A Fuzzfile with syntax errors will return an error similar to this:

$ fuzzball workflow validate ./printer.fz
yaml: unmarshal errors:
  line 2: field jerbs not found in type api.WorkflowDefinition