Matejrisek/actions/on failure

.changes/v1.15/ENHANCEMENTS-20251128-112428.yaml

@@ -0,0 +1,5 @@
+kind: ENHANCEMENTS
+body: 'actions: `action_trigger` block now supports `on_failure` attribute, which allows specifying terraform behavior on action failure.'
+time: 2025-11-28T11:24:28.415647+01:00
+custom:
+    Issue: "37945"

internal/configs/action.go

@@ -45,6 +45,7 @@ type ActionTrigger struct {
 	Condition hcl.Expression
 	Events    []ActionTriggerEvent
 	Actions   []ActionRef // References to actions
+	OnFailure ActionTriggerOnFailure
 
 	DeclRange hcl.Range
 }
@@ -55,6 +56,17 @@ type ActionTriggerEvent int
 
 //go:generate go tool golang.org/x/tools/cmd/stringer -type ActionTriggerEvent
 
+// ActionTriggerOnFailure is an enum capturing the types of behaviors available
+// to action trigger on_failure attribute.
+type ActionTriggerOnFailure int
+
+const (
+	ActionTriggerOnFailureFail ActionTriggerOnFailure = iota
+	ActionTriggerOnFailureContinue
+)
+
+//go:generate go tool golang.org/x/tools/cmd/stringer -type ActionTriggerOnFailure
+
 const (
 	Unknown ActionTriggerEvent = iota
 	BeforeCreate
@@ -78,6 +90,7 @@ func decodeActionTriggerBlock(block *hcl.Block) (*ActionTrigger, hcl.Diagnostics
 		Events:    []ActionTriggerEvent{},
 		Actions:   []ActionRef{},
 		Condition: nil,
+		OnFailure: ActionTriggerOnFailureFail,
 	}
 
 	content, bodyDiags := block.Body.Content(actionTriggerSchema)
@@ -137,6 +150,22 @@ func decodeActionTriggerBlock(block *hcl.Block) (*ActionTrigger, hcl.Diagnostics
 		a.Actions = actionRefs
 	}
 
+	if attr, exists := content.Attributes["on_failure"]; exists {
+		switch hcl.ExprAsKeyword(attr.Expr) {
+		case "continue":
+			a.OnFailure = ActionTriggerOnFailureContinue
+		case "fail":
+			a.OnFailure = ActionTriggerOnFailureFail
+		default:
+			diags = append(diags, &hcl.Diagnostic{
+				Severity: hcl.DiagError,
+				Summary:  "Invalid \"on_failure\" keyword",
+				Detail:   "The \"on_failure\" argument requires one of the following keywords: continue or fail.",
+				Subject:  attr.Expr.Range().Ptr(),
+			})
+		}
+	}
+
 	if len(a.Actions) == 0 {
 		diags = append(diags, &hcl.Diagnostic{
 			Severity: hcl.DiagError,
@@ -266,6 +295,10 @@ var actionTriggerSchema = &hcl.BodySchema{
 			Name:     "actions",
 			Required: true,
 		},
+		{
+			Name:     "on_failure",
+			Required: false,
+		},
 	},
 }
 

internal/configs/action_test.go

@@ -223,3 +223,46 @@ func TestDecodeActionTriggerBlock(t *testing.T) {
 		})
 	}
 }
+
+func TestDecodeActionTriggerBlock_onFailure(t *testing.T) {
+	fooActionExpr := hcltest.MockExprTraversalSrc("action.action_type.foo")
+
+	testData := map[string]struct {
+		valid   bool
+		diagMsg string
+	}{
+		"continue": {true, ""},
+		"fail":     {true, ""},
+		"foo": {false, "MockExprLiteral:0,0-0: Invalid " +
+			"\"on_failure\" keyword; The \"on_failure\" argument requires " +
+			"one of the following keywords: continue or fail."},
+	}
+	for keyword, td := range testData {
+		t.Run("", func(t *testing.T) {
+			givenActionTriggerBlock := &hcl.Block{
+				Type: "action_trigger",
+				Body: hcltest.MockBody(&hcl.BodyContent{
+					Attributes: hcltest.MockAttrs(map[string]hcl.Expression{
+						"events": hcltest.MockExprList([]hcl.Expression{
+							hcltest.MockExprTraversalSrc("before_create"),
+						}),
+						"actions": hcltest.MockExprList([]hcl.Expression{
+							fooActionExpr,
+						}),
+						"on_failure": hcltest.MockExprTraversalSrc(keyword),
+					}),
+				}),
+			}
+
+			_, diags := decodeActionTriggerBlock(givenActionTriggerBlock)
+
+			if diags.HasErrors() && td.valid {
+				t.Fatalf("keyword %s should be valid but has returned"+
+					" diags: %v", keyword, diags)
+			} else if !diags.HasErrors() && !td.valid {
+				t.Fatalf("keyword %s should have been invalid but was"+
+					"valid.", keyword)
+			}
+		})
+	}
+}

internal/configs/parser_test.go

@@ -13,7 +13,7 @@ import (
 
 	"github.com/davecgh/go-spew/spew"
 
-	version "github.com/hashicorp/go-version"
+	"github.com/hashicorp/go-version"
 	"github.com/hashicorp/hcl/v2"
 	"github.com/spf13/afero"
 )

internal/plans/action_invocation.go

@@ -38,6 +38,8 @@ type ActionTrigger interface {
 
 	TriggerEvent() configs.ActionTriggerEvent
 
+	TriggerOnFailure() configs.ActionTriggerOnFailure
+
 	String() string
 
 	Equals(to ActionTrigger) bool
@@ -55,6 +57,8 @@ type LifecycleActionTrigger struct {
 	// Information about the trigger
 	// The event that triggered this action invocation.
 	ActionTriggerEvent configs.ActionTriggerEvent
+	// Hint to Terraform how to handle action failure
+	ActionTriggerOnFailure configs.ActionTriggerOnFailure
 	// The index of the action_trigger block that triggered this invocation.
 	ActionTriggerBlockIndex int
 	// The index of the action in the events list of the action_trigger block
@@ -65,6 +69,10 @@ func (t *LifecycleActionTrigger) TriggerEvent() configs.ActionTriggerEvent {
 	return t.ActionTriggerEvent
 }
 
+func (t *LifecycleActionTrigger) TriggerOnFailure() configs.ActionTriggerOnFailure {
+	return t.ActionTriggerOnFailure
+}
+
 func (t *LifecycleActionTrigger) actionTriggerSigil() {}
 
 func (t *LifecycleActionTrigger) String() string {
@@ -110,6 +118,11 @@ func (t *InvokeActionTrigger) TriggerEvent() configs.ActionTriggerEvent {
 	return configs.Invoke
 }
 
+func (t *InvokeActionTrigger) TriggerOnFailure() configs.ActionTriggerOnFailure {
+	// We always fail on direct invocation
+	return configs.ActionTriggerOnFailureFail
+}
+
 func (t *InvokeActionTrigger) Equals(other ActionTrigger) bool {
 	_, ok := other.(*InvokeActionTrigger)
 	if !ok {