Disable support for Exec-type commands in the preStart lifecycle

As suggested by David, do not support preStart Exec-type commands in
devfiles and instead return an error.

Signed-off-by: Angel Misevski <[email protected]>

pkg/library/lifecycle.go

@@ -13,9 +13,14 @@
 package library
 
 import (
+	"fmt"
+
 	"github.com/devfile/api/pkg/apis/workspaces/v1alpha1"
 )
 
+// GetInitContainers partitions the components in a devfile's flattened spec into initContainer and non-initContainer lists
+// based off devfile lifecycle bindings and commands. Note that a component can appear in both lists, if e.g. it referred to
+// in a preStart command and in a regular command.
 func GetInitContainers(devfile v1alpha1.DevWorkspaceTemplateSpecContent) (initContainers, mainComponents []v1alpha1.Component, err error) {
 	components := devfile.Components
 	commands := devfile.Commands
@@ -29,6 +34,10 @@ func GetInitContainers(devfile v1alpha1.DevWorkspaceTemplateSpecContent) (initCo
 	if err != nil {
 		return nil, nil, err
 	}
+	// Check that commands in PreStart lifecycle binding are supported
+	if err = checkEventCommandsValidity(initCommands); err != nil {
+		return nil, nil, err
+	}
 	initComponentKeys, err := commandListToComponentKeys(initCommands)
 	if err != nil {
 		return nil, nil, err
@@ -64,3 +73,20 @@ func GetInitContainers(devfile v1alpha1.DevWorkspaceTemplateSpecContent) (initCo
 
 	return initContainers, mainComponents, nil
 }
+
+func checkEventCommandsValidity(initCommands []v1alpha1.Command) error {
+	for _, cmd := range initCommands {
+		commandType, err := getCommandType(cmd)
+		if err != nil {
+			return err
+		}
+		switch commandType {
+		case v1alpha1.ApplyCommandType:
+			continue
+		default:
+			// How a prestart exec command should be implemented is undefined currently, so we reject it.
+			return fmt.Errorf("only apply-type commands are supported in the prestart lifecycle binding")
+		}
+	}
+	return nil
+}

pkg/library/lifecycle_test.go

@@ -48,7 +48,7 @@ func loadTestCaseOrPanic(t *testing.T, testFilename string) testCase {
 	if err := yaml.Unmarshal(bytes, &test); err != nil {
 		t.Fatal(err)
 	}
-	t.Log(fmt.Printf("Read file:\n %+v \n\n", test))
+	t.Log(fmt.Sprintf("Read file:\n %+v \n\n", test))
 	return test
 }
 
@@ -66,7 +66,7 @@ func TestGetInitContainers(t *testing.T) {
 			assert.True(t, len(tt.Input.Components) > 0, "Input defines no components")
 			gotInitContainers, gotMainComponents, err := GetInitContainers(tt.Input)
 			if tt.Output.ErrRegexp != nil && assert.Error(t, err) {
-				assert.Regexp(t, tt.Output.ErrRegexp, err.Error(), "Error message should match")
+				assert.Regexp(t, *tt.Output.ErrRegexp, err.Error(), "Error message should match")
 			} else {
 				assert.Equal(t, tt.Output.InitContainers, gotInitContainers, "Init containers should match expected")
 				assert.Equal(t, tt.Output.MainContainers, gotMainComponents, "Main containers should match expected")

pkg/library/testdata/lifecycle/init_and_main_container.yaml

@@ -9,10 +9,9 @@ input:
         name: test-container2
         image: my-image
   commands:
-    - exec:
+    - apply:
         id: test_preStart_command
         component: test-container1
-        command: "test_command"
     - exec:
         id: test_regular_command
         component: test-container1

pkg/library/testdata/lifecycle/prestart_exec_command.yaml

@@ -26,4 +26,4 @@ output:
     - container:
         name: test-container2
         image: my-image
-  errRegexp:
+  errRegexp: "only apply-type commands are supported in the prestart lifecycle binding"