TEP-0154: Enable concise resolver syntax

This PR enables concise resolver syntax as per TEP 0154.
It allows users to pass a url like string to Taskref/name field. In turn, the Tekton controller passes the string to the Resolution Request under the name `resolutionName` which the resolvers can parse and resolve.

config/config-feature-flags.yaml

@@ -131,3 +131,5 @@ data:
   enable-artifacts: "false"
   # Setting this flag to "true" will enable the built-in param input validation via param enum.
   enable-param-enum: "false"
+  # Setting this flag to "true" will enable the use of concise resolver syntax
+  enable-concise-resolver-syntax: "false"

docs/how-to-write-a-resolver.md

@@ -220,6 +220,32 @@ func (r *resolver) ValidateParams(ctx context.Context, params map[string]string)
 You'll also need to add the `"errors"` package to your list of imports at
 the top of the file.
 
+## The `ValidateResolutionName` method
+
+The `ValidateResolutionName` method checks that the `resolutionName` submitted as part of
+a resolution request is valid and can be parsed by the resolver. Our example resolver expects
+format for the `resolutionName` to be `demoscheme://<path>` so we'll validate this format.
+
+```go
+// ValidateResolutionName ensures resolutionName from a request is as expected.
+func (r *resolver) ValidateResolutionName(ctx context.Context, resolutionName string) error {
+  u, err := url.ParseRequestURI(resolutionName)
+  if err != nil {
+    return err
+  }
+  if u.Scheme != "demoscheme" {
+    return errors.New("Invalid Scheme. Want %s, Got %s", "demoscheme", u.Scheme)
+  }
+  if u.Path == "" {
+    return errors.New("Empty path.")
+  }
+  return nil
+}
+```
+
+You'll also need to add the `net/url` and `"errors"` package to your list of imports at
+the top of the file.
+
 ## The `Resolve` method
 
 We implement the `Resolve` method to do the heavy lifting of fetching
@@ -233,8 +259,8 @@ The method signature we're implementing here has a
 is another type we have to implement but it has a small footprint:
 
 ```go
-// Resolve uses the given params to resolve the requested file or resource.
-func (r *resolver) Resolve(ctx context.Context, params map[string]string) (framework.ResolvedResource, error) {
+// Resolve uses the given resolutionName or params to resolve the requested file or resource.
+func (r *resolver) Resolve(ctx context.Context, resolutionName string, params map[string]string) (framework.ResolvedResource, error) {
   return &myResolvedResource{}, nil
 }
 

docs/pipeline-api.md

@@ -3494,6 +3494,10 @@ Example: &ldquo;task/git-clone/0.8/git-clone.yaml&rdquo;</p>
 </tr>
 </tbody>
 </table>
+<h3 id="tekton.dev/v1.RemoteResolutionUrl">RemoteResolutionUrl
+(<code>string</code> alias)</h3>
+<div>
+</div>
 <h3 id="tekton.dev/v1.ResolverName">ResolverName
 (<code>string</code> alias)</h3>
 <p>

go.mod

@@ -1,6 +1,8 @@
 module github.com/tektoncd/pipeline
 
-go 1.19
+go 1.21
+
+toolchain go1.21.6
 
 require (
 	github.com/Microsoft/go-winio v0.6.1 // indirect