POC: experimental --global flag.

CHANGELOG.md

@@ -24,6 +24,8 @@ Given a version number `MAJOR.MINOR.PATCH`, we increment the:
 
 ### Added
 
+- Add `generate_*.inherit` attribute for controlling if generate blocks must be inherited
+  into child stacks.
 - Add experimental support for `tmgen` file extension for easy code generation/templating
   of existing infrastructure. You can enable it with `terramate.config.experimental = ["tmgen"]`.
 

cmd/terramate/cli/cli.go

@@ -147,19 +147,20 @@ type cliSpec struct {
 	} `cmd:"" help:"List stacks."`
 
 	Run struct {
-		CloudStatus                string        `help:"Filter by Terramate Cloud status of the stack."`
-		CloudSyncDeployment        bool          `default:"false" help:"Synchronize the command as a new deployment to Terramate Cloud."`
-		CloudSyncDriftStatus       bool          `default:"false" help:"Synchronize the command as a new drift run to Terramate Cloud."`
-		CloudSyncPreview           bool          `default:"false" help:"Synchronize the command as a new preview to Terramate Cloud."`
-		CloudSyncLayer             preview.Layer `default:"" help:"Set a customer layer for synchronizing a preview to Terramate Cloud."`
-		CloudSyncTerraformPlanFile string        `default:"" help:"Add details of the Terraform Plan file to the synchronization to Terramate Cloud."`
-		DebugPreviewURL            string        `hidden:"true" default:"" help:"Create a debug preview URL to Terramate Cloud details."`
-		ContinueOnError            bool          `default:"false" help:"Do not stop execution when an error occurs."`
-		NoRecursive                bool          `default:"false" help:"Do not recurse into nested child stacks."`
-		DryRun                     bool          `default:"false" help:"Plan the execution but do not execute it."`
-		Reverse                    bool          `default:"false" help:"Reverse the order of execution."`
-		Eval                       bool          `default:"false" help:"Evaluate command arguments as HCL strings interpolating Globals, Functions and Metadata."`
-		Terragrunt                 bool          `default:"false" help:"Use terragrunt when generating planfile for Terramate Cloud sync."`
+		CloudStatus                string            `help:"Filter by Terramate Cloud status of the stack."`
+		CloudSyncDeployment        bool              `default:"false" help:"Synchronize the command as a new deployment to Terramate Cloud."`
+		CloudSyncDriftStatus       bool              `default:"false" help:"Synchronize the command as a new drift run to Terramate Cloud."`
+		CloudSyncPreview           bool              `default:"false" help:"Synchronize the command as a new preview to Terramate Cloud."`
+		CloudSyncLayer             preview.Layer     `default:"" help:"Set a customer layer for synchronizing a preview to Terramate Cloud."`
+		CloudSyncTerraformPlanFile string            `default:"" help:"Add details of the Terraform Plan file to the synchronization to Terramate Cloud."`
+		DebugPreviewURL            string            `hidden:"true" default:"" help:"Create a debug preview URL to Terramate Cloud details."`
+		ContinueOnError            bool              `default:"false" help:"Do not stop execution when an error occurs."`
+		NoRecursive                bool              `default:"false" help:"Do not recurse into nested child stacks."`
+		DryRun                     bool              `default:"false" help:"Plan the execution but do not execute it."`
+		Reverse                    bool              `default:"false" help:"Reverse the order of execution."`
+		Eval                       bool              `default:"false" help:"Evaluate command arguments as HCL strings interpolating Globals, Functions and Metadata."`
+		Terragrunt                 bool              `default:"false" help:"Use terragrunt when generating planfile for Terramate Cloud sync."`
+		Global                     map[string]string `short:"g" help:"set/override globals. eg.: --global name=<expr>"`
 
 		// Note: 0 is not the real default value here, this is just a workaround.
 		// Kong doesn't support having 0 as the default value in case the flag isn't set, but K in case it's set without a value.
@@ -172,7 +173,8 @@ type cliSpec struct {
 	} `cmd:"" help:"Run command in the stacks"`
 
 	Generate struct {
-		DetailedExitCode bool `default:"false" help:"Return a detailed exit code: 0 nothing changed, 1 an error happened, 2 changes were made."`
+		Global           map[string]string `short:"g" help:"set/override globals. eg.: --global name=<expr>"`
+		DetailedExitCode bool              `default:"false" help:"Return a detailed exit code: 0 nothing changed, 1 an error happened, 2 changes were made."`
 	} `cmd:"" help:"Run Code Generation in stacks."`
 
 	Script struct {
@@ -188,7 +190,8 @@ type cliSpec struct {
 			DryRun          bool   `default:"false" help:"Plan the execution but do not execute it."`
 			Reverse         bool   `default:"false" help:"Reverse the order of execution."`
 
-			Cmds []string `arg:"" optional:"true" passthrough:"" help:"Script to execute."`
+			Cmds   []string          `arg:"" optional:"true" passthrough:"" help:"Script to execute."`
+			Global map[string]string `short:"g" help:"set/override globals. eg.: --global name=<expr>"`
 
 			// See above comment regarding for run --parallel.
 			Parallel int `short:"j" optional:"true" help:"Run independent stacks in parallel."`
@@ -202,8 +205,11 @@ type cliSpec struct {
 			Metadata        struct{} `cmd:"" help:"Show metadata available in stacks."`
 			Globals         struct{} `cmd:"" help:"Show globals available in stacks."`
 			GenerateOrigins struct {
+				Global map[string]string `short:"g" help:"set/override globals. eg.: --global name=<expr>"`
 			} `cmd:"" help:"Show details about generated code in stacks."`
-			RuntimeEnv struct{} `cmd:"" help:"Show available run-time environment variables (ENV) in stacks."`
+			RuntimeEnv struct {
+				Global map[string]string `short:"g" help:"set/override globals. eg.: --global name=<expr>"`
+			} `cmd:"" help:"Show available run-time environment variables (ENV) in stacks."`
 		} `cmd:"" help:"Show configuration details of stacks."`
 	} `cmd:"" help:"Debug Terramate configuration."`
 
@@ -1003,7 +1009,7 @@ func (c *cli) gencodeWithVendor() (generate.Report, download.Report) {
 
 	log.Debug().Msg("generating code")
 
-	report := generate.Do(c.cfg(), c.vendorDir(), vendorRequestEvents)
+	report := generate.Do(c.cfg(), c.vendorDir(), vendorRequestEvents, c.parsedArgs.Generate.Global)
 
 	log.Debug().Msg("code generation finished, waiting for vendor requests to be handled")
 
@@ -1629,7 +1635,7 @@ func (c *cli) printRuntimeEnv() {
 	}
 
 	for _, stackEntry := range c.filterStacks(report.Stacks) {
-		envVars, err := run.LoadEnv(c.cfg(), stackEntry.Stack)
+		envVars, err := run.LoadEnv(c.cfg(), stackEntry.Stack, c.parsedArgs.Debug.Show.RuntimeEnv.Global)
 		if err != nil {
 			fatal("loading stack run environment", err)
 		}
@@ -1822,7 +1828,7 @@ func (c *cli) generateDebug() {
 		selectedStacks[stack.Dir()] = struct{}{}
 	}
 
-	results, err := generate.Load(c.cfg(), c.vendorDir())
+	results, err := generate.Load(c.cfg(), c.vendorDir(), c.parsedArgs.Debug.Show.GenerateOrigins.Global)
 	if err != nil {
 		fatal("generate debug: loading generated code", err)
 	}
@@ -1861,7 +1867,7 @@ func (c *cli) printStacksGlobals() {
 
 	for _, stackEntry := range c.filterStacks(report.Stacks) {
 		stack := stackEntry.Stack
-		report := globals.ForStack(c.cfg(), stack)
+		report := globals.ForStack(c.cfg(), stack, nil)
 		if err := report.AsError(); err != nil {
 			fatal(sprintf("listing stacks globals: loading stack at %s", stack.Dir), err)
 		}
@@ -2123,7 +2129,7 @@ func envVarIsSet(val string) bool {
 	return val != "" && val != "0" && val != "false"
 }
 
-func (c *cli) checkOutdatedGeneratedCode() {
+func (c *cli) checkOutdatedGeneratedCode(overrideGlobals map[string]string) {
 	logger := log.With().
 		Str("action", "checkOutdatedGeneratedCode()").
 		Logger()
@@ -2132,7 +2138,7 @@ func (c *cli) checkOutdatedGeneratedCode() {
 		return
 	}
 
-	outdatedFiles, err := generate.DetectOutdated(c.cfg(), c.vendorDir())
+	outdatedFiles, err := generate.DetectOutdated(c.cfg(), c.vendorDir(), overrideGlobals)
 	if err != nil {
 		fatal("failed to check outdated code on project", err)
 	}

cmd/terramate/cli/run.go

@@ -46,8 +46,9 @@ const (
 
 // stackRun contains a list of tasks to be run per stack.
 type stackRun struct {
-	Stack *config.Stack
-	Tasks []stackRunTask
+	Stack           *config.Stack
+	Tasks           []stackRunTask
+	OverrideGlobals map[string]string
 }
 
 // stackCloudRun is a stackRun, but with a single task, because the cloud API only supports
@@ -99,7 +100,7 @@ func (c *cli) runOnStacks() {
 		fatal("run expects a cmd", nil)
 	}
 
-	c.checkOutdatedGeneratedCode()
+	c.checkOutdatedGeneratedCode(c.parsedArgs.Run.Global)
 	c.checkCloudSync()
 
 	var stacks config.List[*config.SortableStack]
@@ -169,6 +170,7 @@ func (c *cli) runOnStacks() {
 					UseTerragrunt:              c.parsedArgs.Run.Terragrunt,
 				},
 			},
+			OverrideGlobals: c.parsedArgs.Generate.Global,
 		}
 		if c.parsedArgs.Run.Eval {
 			run.Tasks[0].Cmd, err = c.evalRunArgs(run.Stack, run.Tasks[0].Cmd)
@@ -531,7 +533,7 @@ func (c *cli) loadAllStackEnvs(runs []stackRun) (map[prj.Path]runutil.EnvVars, e
 	errs := errors.L()
 	stackEnvs := map[prj.Path]runutil.EnvVars{}
 	for _, run := range runs {
-		env, err := runutil.LoadEnv(c.cfg(), run.Stack)
+		env, err := runutil.LoadEnv(c.cfg(), run.Stack, run.OverrideGlobals)
 		errs.Append(err)
 		stackEnvs[run.Stack.Dir] = env
 	}

cmd/terramate/cli/script_run.go

@@ -23,7 +23,7 @@ import (
 
 func (c *cli) runScript() {
 	c.gitSafeguardDefaultBranchIsReachable()
-	c.checkOutdatedGeneratedCode()
+	c.checkOutdatedGeneratedCode(c.parsedArgs.Script.Run.Global)
 
 	var stacks config.List[*config.SortableStack]
 	if c.parsedArgs.Script.Run.NoRecursive {
@@ -75,9 +75,12 @@ func (c *cli) runScript() {
 		}
 
 		for _, st := range result.Stacks {
-			run := stackRun{Stack: st.Stack}
+			run := stackRun{
+				Stack:           st.Stack,
+				OverrideGlobals: c.parsedArgs.Generate.Global,
+			}
 
-			ectx, err := scriptEvalContext(c.cfg(), st.Stack)
+			ectx, err := scriptEvalContext(c.cfg(), st.Stack, c.parsedArgs.Script.Run.Global)
 			if err != nil {
 				fatal("failed to get context", err)
 			}
@@ -196,8 +199,8 @@ func printScriptCommand(w io.Writer, stack *config.Stack, run stackRunTask) {
 	fmt.Fprintln(w, prompt, color.YellowString(strings.Join(run.Cmd, " ")))
 }
 
-func scriptEvalContext(root *config.Root, st *config.Stack) (*eval.Context, error) {
-	globalsReport := globals.ForStack(root, st)
+func scriptEvalContext(root *config.Root, st *config.Stack, overrideGlobals map[string]string) (*eval.Context, error) {
+	globalsReport := globals.ForStack(root, st, overrideGlobals)
 	if err := globalsReport.AsError(); err != nil {
 		return nil, err
 	}

cmd/terramate/e2etests/core/generate_test.go

@@ -475,6 +475,60 @@ func TestGenerateWarnsForTmGenNonInheritable(t *testing.T) {
 	})
 }
 
+func TestGenerateFileNonInheritableOutsideStackGeneratesWarning(t *testing.T) {
+	t.Parallel()
+
+	s := sandbox.NoGit(t, true)
+	s.BuildTree([]string{
+		"d:non-stack",
+	})
+
+	s.RootEntry().
+		CreateDir("non-stack").
+		CreateFile(
+			config.DefaultFilename,
+			GenerateFile(
+				Labels("test.txt"),
+				Bool("inherit", false),
+				Str("content", "test"),
+			).String(),
+		)
+
+	tmcli := NewCLI(t, s.RootDir())
+	AssertRunResult(t, tmcli.Run("generate"), RunExpected{
+		Stdout:      "Nothing to do, generated code is up to date\n",
+		StderrRegex: "Warning: non-inheritable generate found outside a stack",
+	})
+}
+
+func TestGenerateHCLNonInheritableOutsideStackGeneratesWarning(t *testing.T) {
+	t.Parallel()
+
+	s := sandbox.NoGit(t, true)
+	s.BuildTree([]string{
+		"d:non-stack",
+	})
+
+	s.RootEntry().
+		CreateDir("non-stack").
+		CreateFile(
+			config.DefaultFilename,
+			GenerateHCL(
+				Labels("test.txt"),
+				Bool("inherit", false),
+				Content(
+					Str("hello", "world"),
+				),
+			).String(),
+		)
+
+	tmcli := NewCLI(t, s.RootDir())
+	AssertRunResult(t, tmcli.Run("generate"), RunExpected{
+		Stdout:      "Nothing to do, generated code is up to date\n",
+		StderrRegex: "Warning: non-inheritable generate found outside a stack",
+	})
+}
+
 type str string
 
 func (s str) String() string {

config/config.go

@@ -508,10 +508,22 @@ func processTmGenFiles(root *Root, cfg *hcl.Config, cfgdir string, dirEntries []
 			Type: "content",
 			Body: body,
 		}
+
+		// should never fail
+		inheritFalse, diags := hclsyntax.ParseExpression([]byte("false"), "<implicit block>", hhcl.InitialPos)
+		if diags.HasErrors() {
+			panic(errors.E(errors.ErrInternal, diags))
+		}
+
+		inheritAttr := &hclsyntax.Attribute{
+			Name: "inherit",
+			Expr: inheritFalse,
+		}
+
 		implicitGenBlock := hcl.GenHCLBlock{
 			IsImplicitBlock: true,
 			Dir:             project.PrjAbsPath(root.HostDir(), cfgdir),
-			NonInheritable:  true,
+			Inherit:         inheritAttr,
 			Range: info.NewRange(root.HostDir(), hhcl.Range{
 				Filename: absFname,
 				Start:    hhcl.InitialPos,