custom-step

Custom step tutorial

This workflow provides a brief tutorial on writing your own steps in Nebula. Use it to gain an understanding of built-in features like parameters, secrets, and outputs.

The workflow should appear on the Workflows page in your Nebula web interface. If you don't see it there, add the workflow from our examples repo on GitHub.

Running the workflow

Follow these steps to run the workflow:

1. Add your sample "secret" to the workflow as a secret.
   1. Click Edit > Secrets.
   2. Click Define new secret and use the following values:
      • KEY: secret
      • VALUE: this is a fake secret
2. Configure your workflow parameters.
   1. Click Run and enter the following parameters:
      • name: Enter your name.

Using the tutorial

After you run the workflow, take a look at the logs for each step to read about what happened.

You can access the following information from the sample workflow run page:

• Click Graph to view a visualization of the workflow and a description of each step.
• Click Code and data to view the YAML and see how to use different Nebula features.
• Click Logs and select a step to view the log output for that step.

For reference, here is a copy of the workflow:

version: v1
description: Custom step tutorial 

parameters:
  name:
    description: what's your name?
  
steps:
- name: introduction
  image: projectnebula/core
  input: 
  -  echo "-------------- INTRODUCTION --------------"
  -  echo "Nebula provides the ability to create custom steps"
  -  echo ""
  -  echo "Ni is a tool in the projectnebula/core image that gives you access to things"
  -  echo "like spec parameters, outputs, and secrets."
  -  echo ""
  -  echo "Let's see what we can do with them."

- name: parameters
  image: projectnebula/core
  dependsOn: introduction
  input: 
  -  echo "-------------- PARAMETERS --------------"
  -  echo "First, let's start with getting your name."
  -  NAME=$(ni get -p {.name})
  -  echo ""
  -  echo "Your name is ${NAME}" 
  -  echo ""
  -  echo "We got this from passing the parameter from the Workflow to the Step through the spec parameter."
  spec: 
    name:
      $type: Parameter
      name: name

- name: secrets 
  image: projectnebula/core
  dependsOn: parameters
  input:
  -  echo "-------------- SECRETS --------------"
  -  echo "Next, let's get a secret"
  -  SECRET=$(ni get -p {.secret})
  -  echo ""
  -  echo "Your secret is ${SECRET}"
  -  echo ""
  -  echo "You can define a secret by declaring the parameter as \$type Secret which must be defined in the Workflow Secrets"
  -  echo "Within the Step, both plaintext parameters and secrets are accessed the same way"
  spec:
    secret:
      $type: Secret
      name: secret

- name: outputs
  image: projectnebula/core
  dependsOn: secrets
  input: 
  -  echo "-------------- OUTPUTS --------------"
  -  echo "Next, let's define an output."
  -  echo "An output can be defined in one step and consumed in a subsequent step."
  -  echo ""
  -  echo "Setting value..."
  -  echo "KEY = key"
  -  echo "VALUE = You are awesome!"
  -  ni output set --key "key" --value "You are awesome"

- name: end 
  image: projectnebula/core
  dependsOn: outputs
  input: 
  -  echo "-------------- OUTPUTS --------------"
  -  echo "Here's where we can use the output of the previous step"
  -  echo "You pass in the output value through the input spec parameters and reference it like any other parameter."
  -  OUTPUT=$(ni get -p {.output})
  -  echo ""
  -  echo "Echoing output from previous step..."
  -  echo "${OUTPUT}"
  -  echo ""
  -  echo "Thanks for trying this workflow!" 
  spec: 
    output:
      $type: Output
      name: key
      taskName: outputs
    confetti: true