feat: introduce azd validate command with pipeline and gate framework

cli/azd/cmd/container.go

@@ -1020,6 +1020,7 @@ func registerCommonDependencies(container *ioc.NestedContainer) {
 
 	// Required for nested actions called from composite actions like 'up'
 	registerAction[*cmd.ProvisionAction](container, "azd-provision-action")
+	registerAction[*cmd.ValidateAction](container, "azd-validate-action")
 	registerAction[*downAction](container, "azd-down-action")
 	registerAction[*configShowAction](container, "azd-config-show-action")
 }

cli/azd/cmd/root.go

@@ -332,6 +332,20 @@ func newRootCmd(
 		}).
 		UseMiddleware("extensions", middleware.NewExtensionsMiddleware)
 
+	root.
+		Add("validate", &actions.ActionDescriptorOptions{
+			Command:        cmd.NewValidateCmd(),
+			FlagsResolver:  cmd.NewValidateFlags,
+			ActionResolver: cmd.NewValidateAction,
+			OutputFormats:  []output.Format{output.JsonFormat, output.NoneFormat},
+			DefaultFormat:  output.NoneFormat,
+			GroupingOptions: actions.CommandGroupOptions{
+				RootLevelHelp: actions.CmdGroupAzure,
+			},
+			RequireLogin: true,
+		}).
+		UseMiddleware("extensions", middleware.NewExtensionsMiddleware)
+
 	root.
 		Add("package", &actions.ActionDescriptorOptions{
 			Command:        newPackageCmd(),

cli/azd/cmd/testdata/TestFigSpec.ts

@@ -6726,6 +6726,21 @@ const completionSpec: Fig.Spec = {
 				},
 			],
 		},
+		{
+			name: ['validate'],
+			description: 'Validate your project configuration and Azure readiness.',
+			options: [
+				{
+					name: ['--gate'],
+					description: 'Run only the specified validation gate (e.g. "local-preflight").',
+					args: [
+						{
+							name: 'gate',
+						},
+					],
+				},
+			],
+		},
 		{
 			name: ['version'],
 			description: 'Print the version number of Azure Developer CLI.',
@@ -8010,6 +8025,10 @@ const completionSpec: Fig.Spec = {
 					name: ['update'],
 					description: 'Updates azd to the latest version.',
 				},
+				{
+					name: ['validate'],
+					description: 'Validate your project configuration and Azure readiness.',
+				},
 				{
 					name: ['version'],
 					description: 'Print the version number of Azure Developer CLI.',

cli/azd/cmd/testdata/TestUsage-azd-validate.snap

@@ -0,0 +1,20 @@
+
+Validate your project configuration and Azure readiness.
+
+Usage
+  azd validate [flags]
+
+Flags
+    -e, --environment string 	: The name of the environment to use.
+        --gate string        	: Run only the specified validation gate (e.g. "local-preflight").
+
+Global Flags
+    -C, --cwd string 	: Sets the current working directory.
+        --debug      	: Enables debugging and diagnostics logging.
+        --docs       	: Opens the documentation for azd validate in your web browser.
+    -h, --help       	: Gets help for validate.
+        --no-prompt  	: Runs without prompts. Uses existing values; fails if any required value or decision cannot be resolved automatically.
+
+Find a bug? Want to let us know how we're doing? Fill out this brief survey: https://aka.ms/azure-dev/hats.
+
+

cli/azd/cmd/testdata/TestUsage-azd.snap

@@ -15,6 +15,7 @@ Commands
     down        	: Delete your project's Azure resources.
     provision   	: Provision Azure resources for your project.
     publish     	: Publish a service to a container registry.
+    validate    	: Validate your project configuration and Azure readiness.
 
   Manage and show settings
     completion  	: Generate shell completion scripts.

cli/azd/internal/cmd/provision_test.go

@@ -96,6 +96,10 @@ func (p *mockProvider) Destroy(_ context.Context, _ provisioning.DestroyOptions)
 
 func (p *mockProvider) EnsureEnv(_ context.Context) error { return nil }
 
+func (p *mockProvider) Validate(_ context.Context) (*provisioning.ValidateResult, error) {
+	return &provisioning.ValidateResult{Skipped: true, SkipReason: "mock"}, nil
+}
+
 func (p *mockProvider) Parameters(_ context.Context) ([]provisioning.Parameter, error) {
 	return nil, nil
 }

cli/azd/internal/cmd/validate.go

@@ -0,0 +1,201 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the MIT License.
+
+package cmd
+
+import (
+	"context"
+	"fmt"
+	"io"
+
+	"github.com/azure/azure-dev/cli/azd/cmd/actions"
+	"github.com/azure/azure-dev/cli/azd/internal"
+	"github.com/azure/azure-dev/cli/azd/pkg/environment"
+	"github.com/azure/azure-dev/cli/azd/pkg/infra/provisioning"
+	"github.com/azure/azure-dev/cli/azd/pkg/input"
+	"github.com/azure/azure-dev/cli/azd/pkg/output"
+	"github.com/azure/azure-dev/cli/azd/pkg/output/ux"
+	"github.com/azure/azure-dev/cli/azd/pkg/project"
+	"github.com/azure/azure-dev/cli/azd/pkg/validate"
+	"github.com/spf13/cobra"
+	"github.com/spf13/pflag"
+)
+
+// ValidateFlags holds the flags for the validate command.
+type ValidateFlags struct {
+	global *internal.GlobalCommandOptions
+	// gate filters the pipeline to run only the specified gate.
+	gate string
+	*internal.EnvFlag
+}
+
+// Bind registers the validate flags on the given flag set.
+func (f *ValidateFlags) Bind(local *pflag.FlagSet, global *internal.GlobalCommandOptions) {
+	f.EnvFlag = &internal.EnvFlag{}
+	f.EnvFlag.Bind(local, global)
+	local.StringVar(
+		&f.gate,
+		"gate",
+		"",
+		"Run only the specified validation gate (e.g. \"local-preflight\").",
+	)
+	f.global = global
+}
+
+// NewValidateFlags creates and binds flags for the validate command.
+func NewValidateFlags(
+	cmd *cobra.Command, global *internal.GlobalCommandOptions,
+) *ValidateFlags {
+	flags := &ValidateFlags{}
+	flags.Bind(cmd.Flags(), global)
+	return flags
+}
+
+// NewValidateCmd creates the cobra command for "azd validate".
+func NewValidateCmd() *cobra.Command {
+	return &cobra.Command{
+		Use:   "validate",
+		Short: "Validate your project configuration and Azure readiness.",
+		Long: `Validate runs a pipeline of validation gates against your project
+and environment to detect issues before provisioning. Each gate performs
+a set of checks (e.g. role assignments, resource quotas, configuration)
+and reports warnings or errors with actionable suggestions.
+
+Use --gate to run a specific gate in isolation.`,
+	}
+}
+
+// ValidateAction implements the azd validate command.
+type ValidateAction struct {
+	flags            *ValidateFlags
+	projectConfig    *project.ProjectConfig
+	projectManager   project.ProjectManager
+	provisionManager *provisioning.Manager
+	env              *environment.Environment
+	console          input.Console
+	formatter        output.Formatter
+	writer           io.Writer
+	gates            []validate.Gate
+}
+
+// NewValidateAction creates a new ValidateAction with all dependencies
+// injected via IoC.
+func NewValidateAction(
+	flags *ValidateFlags,
+	projectConfig *project.ProjectConfig,
+	projectManager project.ProjectManager,
+	provisionManager *provisioning.Manager,
+	env *environment.Environment,
+	console input.Console,
+	formatter output.Formatter,
+	writer io.Writer,
+) actions.Action {
+	action := &ValidateAction{
+		flags:            flags,
+		projectConfig:    projectConfig,
+		projectManager:   projectManager,
+		provisionManager: provisionManager,
+		env:              env,
+		console:          console,
+		formatter:        formatter,
+		writer:           writer,
+	}
+
+	// Register built-in gates
+	action.RegisterGate(validate.NewProjectConfigGate())
+	action.RegisterGate(
+		validate.NewLocalPreflightGate(provisionManager))
+
+	return action
+}
+
+// RegisterGate adds a validation gate to be executed by this action.
+// Gates are executed in the order they are registered.
+func (a *ValidateAction) RegisterGate(gate validate.Gate) {
+	a.gates = append(a.gates, gate)
+}
+
+// Run executes the validation pipeline and displays results.
+func (a *ValidateAction) Run(ctx context.Context) (*actions.ActionResult, error) {
+	a.console.MessageUxItem(ctx, &ux.MessageTitle{
+		Title:     "Validating project (azd validate)",
+		TitleNote: "Running validation checks against your project and environment",
+	})
+
+	if err := a.projectManager.Initialize(ctx, a.projectConfig); err != nil {
+		return nil, err
+	}
+
+	pipeline := validate.NewPipeline(validate.PipelineOptions{
+		OnError: validate.OnErrorContinue,
+	})
+
+	// Register gates, optionally filtering by --gate flag
+	gateFilter := a.flags.gate
+	registered := 0
+	for _, gate := range a.gates {
+		if gateFilter != "" && gate.Name() != gateFilter {
+			continue
+		}
+		pipeline.AddGate(gate)
+		registered++
+	}
+
+	if gateFilter != "" && registered == 0 {
+		return nil, fmt.Errorf(
+			"unknown gate %q; available gates: %s",
+			gateFilter, a.availableGateNames(),
+		)
+	}
+
+	pCtx := &validate.PipelineContext{
+		Console:     a.console,
+		Environment: a.env,
+		Project:     a.projectConfig,
+	}
+
+	result, err := pipeline.Run(ctx, pCtx)
+	if err != nil {
+		return nil, err
+	}
+
+	// Display the validation report
+	report := &validate.ValidationReport{Result: result}
+	a.console.MessageUxItem(ctx, report)
+
+	// Format output for --output json
+	if a.formatter.Kind() == output.JsonFormat {
+		if err := a.formatter.Format(result, a.writer, nil); err != nil {
+			return nil, fmt.Errorf("formatting output: %w", err)
+		}
+	}
+
+	if result.HasErrors() {
+		return &actions.ActionResult{
+			Message: &actions.ResultMessage{
+				Header: fmt.Sprintf(
+					"Validation found %d error(s) and %d warning(s).",
+					result.TotalErrors(), result.TotalWarnings(),
+				),
+			},
+		}, nil
+	}
+
+	return &actions.ActionResult{
+		Message: &actions.ResultMessage{
+			Header: "Validation completed successfully.",
+		},
+	}, nil
+}
+
+// availableGateNames returns a comma-separated list of registered gate names.
+func (a *ValidateAction) availableGateNames() string {
+	if len(a.gates) == 0 {
+		return "(none registered)"
+	}
+	names := make([]string, len(a.gates))
+	for i, g := range a.gates {
+		names[i] = g.Name()
+	}
+	return fmt.Sprintf("%v", names)
+}

cli/azd/internal/grpcserver/external_provisioning_provider.go

@@ -218,6 +218,17 @@ func (p *ExternalProvisioningProvider) Destroy(
 	}, nil
 }
 
+// Validate is not yet supported for extension provisioning providers.
+// Returns a skipped result.
+func (p *ExternalProvisioningProvider) Validate(
+	ctx context.Context,
+) (*provisioning.ValidateResult, error) {
+	return &provisioning.ValidateResult{
+		Skipped:    true,
+		SkipReason: "validation not yet supported for extension providers",
+	}, nil
+}
+
 // EnsureEnv ensures the environment is configured properly.
 func (p *ExternalProvisioningProvider) EnsureEnv(ctx context.Context) error {
 	req := &azdext.ProvisioningMessage{

cli/azd/pkg/devcenter/provision_provider.go

@@ -249,6 +249,16 @@ func (p *ProvisionProvider) Preview(ctx context.Context) (*provisioning.DeployPr
 	return nil, fmt.Errorf("preview is not supported for devcenter")
 }
 
+// Validate is not yet supported for Dev Center.
+func (p *ProvisionProvider) Validate(
+	ctx context.Context,
+) (*provisioning.ValidateResult, error) {
+	return &provisioning.ValidateResult{
+		Skipped:    true,
+		SkipReason: "validation not yet supported for Dev Center provider",
+	}, nil
+}
+
 // Destroy destroys the environment by deleting the ADE environment
 func (p *ProvisionProvider) Destroy(
 	ctx context.Context,