Task Operations Usage¶

Tasks are the atomic units of work in DRP. Each task defines one or more templates (scripts or configuration files) that are rendered and executed on a machine during provisioning. Use drpcli tasks to manage the task library.

List Tasks¶

Bash

# List all defined tasks
drpcli tasks list

# List tasks and show only names
drpcli tasks list | jq -r '.[].Name' | sort

# Search for tasks by name pattern
drpcli tasks list | jq -r '[.[] | select(.Name | contains("ntp"))] | .[].Name'

Get Task Details¶

Bash

# Show a specific task by name
drpcli tasks show my-configure-ntp

# Show the required parameters for a task
drpcli tasks show my-configure-ntp | jq '{RequiredParams:.RequiredParams,OptionalParams:.OptionalParams}'

# Show template names within a task
drpcli tasks show my-configure-ntp | jq '[.Templates[].Name]'

Create a Task¶

Tasks can be created from JSON or YAML. The most important fields are Name, Templates, RequiredParams, and OptionalParams.

Bash

# Create a simple inline task
drpcli tasks create '{
  "Name": "hello-world",
  "Description": "Print hello world",
  "Templates": [
    {
      "Name": "hello.sh",
      "Path": "/tmp/hello.sh",
      "Contents": "#!/bin/bash\necho \"Hello from {{ .Machine.Name }}\"\n"
    }
  ]
}'

# Create a task from a YAML file
drpcli tasks create - < my-task.yaml

A task YAML with declared parameters:

YAML

Name: configure-ntp
Description: "Configure NTP servers on the target machine"
RequiredParams:
  - ntp/servers
OptionalParams:
  - ntp/pool-name
Templates:
  - Name: configure-ntp.sh
    Path: /tmp/configure-ntp.sh
    Contents: |
      #!/bin/bash
      set -e
      {{ range (.Param "ntp/servers") -}}
      echo "server {{ . }} iburst" >> /etc/chrony.conf
      {{ end -}}
      systemctl restart chronyd

Bash

drpcli tasks create - < configure-ntp.yaml

Update a Task¶

Bash

# Update a task's description
drpcli tasks update my-configure-ntp '{"Description":"Configure NTP servers using chrony"}'

# Add a required parameter to an existing task
drpcli tasks update my-configure-ntp '{"RequiredParams":["ntp/servers","ntp/pool-name"]}'

# Replace a task's template contents (full update)
drpcli tasks update my-configure-ntp - < updated-task.yaml

Destroy a Task¶

Bash

# Remove a task (fails if the task is referenced by a stage)
drpcli tasks destroy my-configure-ntp

Before destroying, check which stages reference the task:

Bash

drpcli stages list | jq -r '.[] | select(.Tasks | contains(["my-configure-ntp"])) | .Name'

Inspect Field Information¶

Bash

# Show the field schema for the task model
drpcli tasks fieldinfo

Using Tasks in Stages¶

Once a task is created, reference it by name in a stage's Tasks list:

Bash

drpcli stages update my-stage '{"Tasks":["configure-ntp","configure-dns","harden-ssh"]}'