Define Margo desired state artifact that enables the state seeking workload management approach

[ajcraig]

Provide feature description below:

Goal: Define the desired state artifact(s) that are produced via the WFM, and retrieved via the edge client, to enable state seeking management of workloads at the edge.

Provide adequate technical acceptance criteria(s) associated with this feature below:

• Defined file type
• Defined file content
  • Enable instance specific configuration to be included via key:value pairs that are compatible with the edge providers.
  • Provide artifact links to pull the manifests for the prescribed workloads
  • Provide a means to include authorization/secure access to the artifact repositories via the WFM server
• Define what manifests are supported for each Margo Device role
  • Standalone Cluster / Cluster leader
    • Helm Manifest links
  • Standalone Device
    • Compose manifest links

Although not required, it is highly encouraged to provide feature use-cases below:

• Deploy and manage instances of workloads within the enrolled edge devices.
• Enables eventual consistency by enabling state seeking patterns.
• Enables immutability by storing desired state outside of the edge device.
  • Could in the future enable disaster recovery / roll back support.

Additional information

• Investigate impact on the strategy if additional storage locations are supported within the deployment specification. See sub issue Expand Helm DeploymentProfile to Support Both OCI Repository and Git/Code Repository #79 for further details.

[ajcraig]

Associated Specification markdowns that will need to be completed prior to feature closeout:

• https://github.com/margo/specification/blob/pre-draft/src/margo-api-reference/workload-api/desired-state-api/desired-state.linkml.yaml
  examples:
• https://github.com/margo/specification/blob/pre-draft/src/margo-api-reference/workload-api/desired-state-api/resources/examples/valid/DesiredState-001.yaml
• https://github.com/margo/specification/blob/pre-draft/src/margo-api-reference/workload-api/desired-state-api/resources/examples/valid/DesiredState-002.yaml