(feat) add condition mapping for when conditions in drone

[bradrydzewski]

@eoinmcafee00 I recommend using %q instead of \"%s\". This will not only quote the string, but will escape any special characters inside the string.

[bradrydzewski]

In the new yaml, the stage id and name are optional and may be empty. If the id is provided we can use it as-is. Else we can use the name as the id. Else we can use the type as the id. Looking at my original code, I can see that I did not account for this scenario. However, the identifiers.Generate function actually handles fallback logic by accepting multiple parameters. So I think we could do the following:

        ID: d.identifiers.Generate(
            slug.Create(stage.ID), 
            slug.Create(stage.Name), 
            slug.Generate(stage.Type),
        ),

It should work something like this:

stages:
- type ci # use "ci" as stage id and name

stages:
- type: ci
  id: foo # use "foo" as stage id and name

stages:
- type: ci
  name: bar # use "bar" as stage id and name

stages:
- type: ci
  id: foo # use "foo" as id and "bar" as name
  name: bar

[jimsheldon]

I am testing this today and I think I stumbled on an important detail.

Since Drone is webhook-driven, the migration will need to create triggers in Harness CI for every pipeline. When a pipeline executes from a trigger event in Harness CI, the <+codebase.*> variables are not available, only <+trigger.*> variables are available.

I think this means we can ignore <+codebase.*> variables in our conversions.

See this documentation for available <+trigger.*> variables.

There isn't a 1-1 match in features between Drone and Harness CI, see Drone's documentation.

Harness CI has:

• By Event via <+trigger.event>
• By Branch via <+trigger.branch>
• By Repository via <+trigger.payload.repository.name> (only tested GitHub, we could possibly parse <+trigger.repoUrl> instead)

Harness CI does not have:

• By Instance
• By Target
• By Cron
• By Status (but when.stageStatus: Failure and when.pipelineStatus: Failure are available)

[jimsheldon]

JEXL supports different operators for pattern matching. I was able to get similar functionality to what Drone gets from doublestar with the =~ operator.

Examples

By Branch

Harness CI yaml

              - step:
                  when:
                    stageStatus: Success
                    condition: <+trigger.branch> =~ "feature-.*"
                  type: Run
                  name: Feature Branch
                  identifier: featurebranch
                  spec:
                    shell: Sh
                    command: |-
                      echo this runs on a feature branch

Drone yaml

steps:
- name: Feature Branch
  commands:
  - echo this runs on a feature branch
  when:
    branch:
    - feature-*

By Repo

Harness CI yaml

              - step:
                  when:
                    stageStatus: Success
                    condition: <+trigger.payload.repository.name> != "my-repo"
                  type: Run
                  name: Not My Repo
                  identifier: notmyrepo
                  spec:
                    shell: Sh
                    command: |-
                      echo do not run for my-repo

Drone yaml

steps:
- name: Not My Repo
  commands:
  - echo do not run for my-repo
  when:
    repo:
      exclude:
      - my-repo