Add wildcard (match all) support to ignore_changes (#8599)

config/config.go

@@ -570,6 +570,15 @@ func (c *Config) Validate() error {
 				}
 			}
 		}
+
+		// Verify ignore_changes contains valid entries
+		for _, v := range r.Lifecycle.IgnoreChanges {
+			if strings.Contains(v, "*") && v != "*" {
+				errs = append(errs, fmt.Errorf(
+					"%s: ignore_changes does not support using a partial string "+
+						"together with a wildcard: %s", n, v))
+			}
+		}
 	}
 
 	for source, vs := range vars {

config/config_test.go

@@ -244,6 +244,20 @@ func TestConfigValidate_dupResource(t *testing.T) {
 	}
 }
 
+func TestConfigValidate_ignoreChanges(t *testing.T) {
+	c := testConfig(t, "validate-ignore-changes")
+	if err := c.Validate(); err != nil {
+		t.Fatalf("err: %s", err)
+	}
+}
+
+func TestConfigValidate_ignoreChangesBad(t *testing.T) {
+	c := testConfig(t, "validate-ignore-changes-bad")
+	if err := c.Validate(); err == nil {
+		t.Fatal("should not be valid")
+	}
+}
+
 func TestConfigValidate_moduleNameBad(t *testing.T) {
 	c := testConfig(t, "validate-module-name-bad")
 	if err := c.Validate(); err == nil {

config/test-fixtures/validate-ignore-changes-bad/main.tf

@@ -0,0 +1,21 @@
+variable "foo" {
+  default = "ami-abcd1234"
+}
+
+variable "bar" {
+  default = "t2.micro"
+}
+
+provider "aws" {
+  access_key = "foo"
+  secret_key = "bar"
+}
+
+resource aws_instance "web" {
+  ami           = "${var.foo}"
+  instance_type = "${var.bar}"
+
+  lifecycle {
+    ignore_changes = ["ami", "instance*"]
+  }
+}

config/test-fixtures/validate-ignore-changes/main.tf

@@ -0,0 +1,21 @@
+variable "foo" {
+  default = "ami-abcd1234"
+}
+
+variable "bar" {
+  default = "t2.micro"
+}
+
+provider "aws" {
+  access_key = "foo"
+  secret_key = "bar"
+}
+
+resource aws_instance "web" {
+  ami           = "${var.foo}"
+  instance_type = "${var.bar}"
+
+  lifecycle {
+    ignore_changes = ["*"]
+  }
+}

terraform/context_apply_test.go

@@ -5034,6 +5034,47 @@ func TestContext2Apply_ignoreChangesWithDep(t *testing.T) {
 	}
 }
 
+func TestContext2Apply_ignoreChangesWildcard(t *testing.T) {
+	m := testModule(t, "apply-ignore-changes-wildcard")
+	p := testProvider("aws")
+	p.ApplyFn = testApplyFn
+	p.DiffFn = testDiffFn
+	ctx := testContext2(t, &ContextOpts{
+		Module: m,
+		Providers: map[string]ResourceProviderFactory{
+			"aws": testProviderFuncFixed(p),
+		},
+	})
+
+	if p, err := ctx.Plan(); err != nil {
+		t.Fatalf("err: %s", err)
+	} else {
+		t.Logf(p.String())
+	}
+
+	state, err := ctx.Apply()
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	mod := state.RootModule()
+	if len(mod.Resources) != 1 {
+		t.Fatalf("bad: %s", state)
+	}
+
+	actual := strings.TrimSpace(state.String())
+	// Expect no changes from original state
+	expected := strings.TrimSpace(`
+aws_instance.foo:
+  ID = foo
+  required_field = set
+  type = aws_instance
+`)
+	if actual != expected {
+		t.Fatalf("expected:\n%s\ngot:\n%s", expected, actual)
+	}
+}
+
 // https://github.com/hashicorp/terraform/issues/7378
 func TestContext2Apply_destroyNestedModuleWithAttrsReferencingResource(t *testing.T) {
 	m := testModule(t, "apply-destroy-nested-module-with-attrs")

terraform/context_plan_test.go

@@ -2326,6 +2326,56 @@ func TestContext2Plan_ignoreChanges(t *testing.T) {
 	}
 }
 
+func TestContext2Plan_ignoreChangesWildcard(t *testing.T) {
+	m := testModule(t, "plan-ignore-changes-wildcard")
+	p := testProvider("aws")
+	p.DiffFn = testDiffFn
+	s := &State{
+		Modules: []*ModuleState{
+			&ModuleState{
+				Path: rootModulePath,
+				Resources: map[string]*ResourceState{
+					"aws_instance.foo": &ResourceState{
+						Primary: &InstanceState{
+							ID: "bar",
+							Attributes: map[string]string{
+								"ami":           "ami-abcd1234",
+								"instance_type": "t2.micro",
+							},
+						},
+					},
+				},
+			},
+		},
+	}
+	ctx := testContext2(t, &ContextOpts{
+		Module: m,
+		Providers: map[string]ResourceProviderFactory{
+			"aws": testProviderFuncFixed(p),
+		},
+		Variables: map[string]interface{}{
+			"foo": "ami-1234abcd",
+			"bar": "t2.small",
+		},
+		State: s,
+	})
+
+	plan, err := ctx.Plan()
+	if err != nil {
+		t.Fatalf("err: %s", err)
+	}
+
+	if len(plan.Diff.RootModule().Resources) > 0 {
+		t.Fatalf("bad: %#v", plan.Diff.RootModule().Resources)
+	}
+
+	actual := strings.TrimSpace(plan.String())
+	expected := strings.TrimSpace(testTerraformPlanIgnoreChangesWildcardStr)
+	if actual != expected {
+		t.Fatalf("bad:\n%s\n\nexpected\n\n%s", actual, expected)
+	}
+}
+
 func TestContext2Plan_moduleMapLiteral(t *testing.T) {
 	m := testModule(t, "plan-module-map-literal")
 	p := testProvider("aws")

terraform/eval_diff.go

@@ -188,7 +188,7 @@ func (n *EvalDiff) processIgnoreChanges(diff *InstanceDiff) error {
 	ignorableAttrKeys := make(map[string]bool)
 	for _, ignoredKey := range ignoreChanges {
 		for k := range diff.CopyAttributes() {
-			if strings.HasPrefix(k, ignoredKey) {
+			if ignoredKey == "*" || strings.HasPrefix(k, ignoredKey) {
 				ignorableAttrKeys[k] = true
 			}
 		}

terraform/terraform_test.go

@@ -1407,6 +1407,19 @@ aws_instance.foo:
   ami = ami-abcd1234
 `
 
+const testTerraformPlanIgnoreChangesWildcardStr = `
+DIFF:
+
+
+
+STATE:
+
+aws_instance.foo:
+  ID = bar
+  ami = ami-abcd1234
+  instance_type = t2.micro
+`
+
 const testTerraformPlanComputedValueInMap = `
 DIFF:
 

terraform/test-fixtures/apply-ignore-changes-wildcard/main.tf

@@ -0,0 +1,7 @@
+resource "aws_instance" "foo" {
+  required_field = "set"
+
+  lifecycle {
+    ignore_changes = ["*"]
+  }
+}

terraform/test-fixtures/plan-ignore-changes-wildcard/main.tf

@@ -0,0 +1,12 @@
+variable "foo" {}
+
+variable "bar" {}
+
+resource "aws_instance" "foo" {
+  ami           = "${var.foo}"
+  instance_type = "${var.bar}"
+
+  lifecycle {
+    ignore_changes = ["*"]
+  }
+}

website/source/docs/configuration/resources.html.md

@@ -83,6 +83,10 @@ include `create_before_destroy`. Referencing a resource that does not include
 ~> **NOTE on ignore\_changes:** Ignored attribute names can be matched by their
 name, not state ID. For example, if an `aws_route_table` has two routes defined
 and the `ignore_changes` list contains "route", both routes will be ignored.
+Additionally you can also use a single entry with a wildcard (e.g. `"*"`)
+which will match all attribute names. Using a partial string together with a
+wildcard (e.g. `"rout*"`) is **not** supported.
+
 
 -------------