separate Step from Sidecar

separate Step from Sidecar

Originally the Sidecar type is an alias of the Step type.
Both #3013 and #1690 will require the two types to divert from each other.
This commit separates the two types and updates code to accomodate convertListOfSteps() which originally depended on theses types to be the same.
Partially based on: https://github.com/tektoncd/pipeline/pull/3013/files

pkg/apis/pipeline/v1beta1/task_types.go

@@ -125,8 +125,15 @@ type Step struct {
 	Script string `json:"script,omitempty"`
 }
 
-// A sidecar has the same data structure as a Step, consisting of a Container, and optional Script.
-type Sidecar = Step
+// Sidecar has nearly the same data structure as Step, consisting of a Container and an optional Script, but does not have the ability to timeout.
+type Sidecar struct {
+	corev1.Container `json:",inline"`
+
+	// Script is the contents of an executable file to execute.
+	//
+	// If Script is not empty, the Step cannot have an Command or Args.
+	Script string `json:"script,omitempty"`
+}
 
 // +k8s:deepcopy-gen:interfaces=k8s.io/apimachinery/pkg/runtime.Object
 // TaskList contains a list of Task

pkg/pod/script.go

@@ -62,7 +62,17 @@ func convertScripts(shellImage string, steps []v1beta1.Step, sidecars []v1beta1.
 	}
 
 	convertedStepContainers := convertListOfSteps(steps, &placeScriptsInit, &placeScripts, "script")
-	sidecarContainers := convertListOfSteps(sidecars, &placeScriptsInit, &placeScripts, "sidecar-script")
+	// As the Sidecar type will divert slightly from the Step type in https://github.com/tektoncd/pipeline/issues/1690 and https://github.com/tektoncd/pipeline/pull/3013,
+	// while convertListOfSteps operates on overlapping fields, Sidecar is converted into Step by copying the overlapping fields between the types to avoid code duplication
+	sideCarSteps := []v1beta1.Step{}
+	for _, step := range sidecars {
+		sidecarStep := v1beta1.Step{
+			step.Container,
+			step.Script,
+		}
+		sideCarSteps = append(sideCarSteps, sidecarStep)
+	}
+	sidecarContainers := convertListOfSteps(sideCarSteps, &placeScriptsInit, &placeScripts, "sidecar-script")
 
 	if placeScripts {
 		return &placeScriptsInit, convertedStepContainers, sidecarContainers

pkg/pod/script_test.go

@@ -35,7 +35,7 @@ func TestConvertScripts_NothingToConvert_EmptySidecars(t *testing.T) {
 		Container: corev1.Container{
 			Image: "step-2",
 		},
-	}}, []v1alpha1.Step{})
+	}}, []v1alpha1.Sidecar{})
 	want := []corev1.Container{{
 		Image: "step-1",
 	}, {
@@ -89,7 +89,7 @@ func TestConvertScripts_NothingToConvert_WithSidecar(t *testing.T) {
 		Container: corev1.Container{
 			Image: "step-2",
 		},
-	}}, []v1alpha1.Step{{
+	}}, []v1alpha1.Sidecar{}{{
 		Container: corev1.Container{
 			Image: "sidecar-1",
 		},
@@ -153,7 +153,7 @@ script-3`,
 			VolumeMounts: preExistingVolumeMounts,
 			Args:         []string{"my", "args"},
 		},
-	}}, []v1alpha1.Step{})
+	}}, []v1alpha1.Sidecar{})
 	wantInit := &corev1.Container{
 		Name:    "place-scripts",
 		Image:   images.ShellImage,
@@ -241,7 +241,7 @@ script-3`,
 			VolumeMounts: preExistingVolumeMounts,
 			Args:         []string{"my", "args"},
 		},
-	}}, []v1alpha1.Step{{
+	}}, []v1alpha1.Sidecar{}{{
 		Script: `#!/bin/sh
 sidecar-1`,
 		Container: corev1.Container{Image: "sidecar-1"},