TEP-0154 Concise Remote Resolver Syntax

[chitrangpatel]

This PR proposes to include a concise remote resolver syntax to reference remote resources.
It addresses the feature request tektoncd/pipeline#7508.

/kind tep

[chitrangpatel]

/assign @wlynch

[chitrangpatel]

cc @chmouel PTAL (specifically for http-resolver) 🙂

[wlynch]

/lgtm

IIUC we loosened the constraints enough that tl;dr this is adding url to the remote resolver request.

[dibyom]

/approve
/hold

Added a hold in case other reviewers want to take a look before the TEP is merged. Feel free to remove after

[vdemeester]

If we want to be consice, couldn't we use name for this instead adding url and duplicating some information (the name) ? I think it would be backward compatible : it's {name}://… we infer the name and we don't read the rest, it's {name} only it's the current syntax that applies. In ResolutionRequest we would pass the url or the parameters and let the resolver handle that (and/or the helper code we provide).

Can we write an example for a custom resolver ? They are part of the resolver "feature set" (to be able to write your own resolver) and thus we should make sure we take them into account in this proposal.

[chitrangpatel]

If we want to be consice, couldn't we use name for this instead adding url and duplicating some information (the name) ? I think it would be backward compatible : it's {name}://… we infer the name and we don't read the rest, it's {name} only it's the current syntax that applies. In ResolutionRequest we would pass the url or the parameters and let the resolver handle that (and/or the helper code we provide).

Just the name alone won't help. That's because it then requires that the value starts with the resolver name. And that does not work with something like the http resolver where the scheme could be http or https.
e.g.
https://github.com/tektoncd/pipeline is probably meant to go to the git resolver.
https://raw.githubusercontent.com/tektoncd/pipeline/main/examples/v1/taskruns/array-default.yaml is meant to go to the http resolver.

So in the above case, the name alone does not work. But name with the resolver works because we know where the resolution request is supposed to go:

taskRef:
  name: "https://github.com/tektoncd/pipeline"
  resolver: git

Can we write an example for a custom resolver ? They are part of the resolver "feature set" (to be able to write your own resolver) and thus we should make sure we take them into account in this proposal.

Can do!

[vdemeester]

@chitrangpatel, yeah, as you commented here, we would want "resolver" to be able to say "I handle those sheme", and some sort of priority.

Now, even with that, the git+https is a slight… tricky one to achieve. If the http resolver has a higher priority than git, would we always let the http resolver handle it, fail, and give it to the next ? In case of an 401 (unauthorized), would we still do the same (with a high level of chance it will be 401 with the git provider as well).

Some history note (that might not have any "impact"), the current syntax is also there because it was decided to be consistent with the rest of the API (on params). The initial proposal looked like

  name: …
  params:
    - foo: bar
    - {name}: {value}

[tekton-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: dibyom, vdemeester

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[chitrangpatel]

/hold cancel

[wlynch]

/lgtm