feat(config): add config command to show resolved per-service configuration

cli/docs/cli-reference.md

@@ -67,6 +67,7 @@ azd app run --environment production
 | `reqs` | Check and verify required tools and optionally auto-generate requirements | [→ Full Spec](commands/reqs.md) |
 | `deps` | Install dependencies for detected projects | [→ Full Spec](commands/deps.md) |
 | `add` | Add a well-known container service to azure.yaml | [→ Full Spec](commands/add.md) |
+| `config` | Show the effective resolved configuration for each service | [→ Full Spec](commands/config.md) |
 | `run` | Run the development environment with service orchestration and lifecycle hooks | [→ Full Spec](commands/run.md) |
 | `test` | Run tests for all services with coverage aggregation | [→ Full Spec](commands/test.md) |
 | `start` | Start stopped services | [→ Full Spec](commands/start.md) |
@@ -307,6 +308,46 @@ azd app add redis --output json
 
 ---
 
+## `azd app config`
+
+Show the configuration azd app resolved from azure.yaml for each service.
+
+### Usage
+
+```bash
+azd app config [service] [flags]
+```
+
+### Examples
+
+```bash
+# Configuration for every service
+azd app config
+
+# Configuration for a single service
+azd app config api
+
+# JSON object keyed by service name
+azd app config --output json
+```
+
+### Flags
+
+| Flag | Short | Type | Default | Description |
+|------|-------|------|---------|-------------|
+| `--output` | `-o` | string | `default` | Output format (default, json) |
+
+### Behavior
+
+- Prints the host, effective service type (marked `explicit` or `inferred`), language, project path, run command, image, ports, and dependencies (uses) for each service.
+- Lists which optional blocks are configured on a service: `docker`, `healthcheck`, `restart`, `resources`, `logs`, `local`, `azure`.
+- Pass a service name to limit output to that service. An unknown name returns an error listing the available services.
+- `--output json` emits an object keyed by service name.
+
+**→ [See full config command specification](commands/config.md)** for details.
+
+---
+
 ## `azd app run`
 
 Starts your development environment based on project type with support for multi-service orchestration.

cli/docs/commands/config.md

@@ -0,0 +1,58 @@
+# azd app config
+
+Show the configuration azd app resolved from azure.yaml for each service.
+
+## Synopsis
+
+```
+azd app config [service] [flags]
+```
+
+## Description
+
+The `config` command reads azure.yaml and prints the configuration for each
+service the way azd app resolves it. This is a static view of the parsed model,
+so you can confirm what the tool sees without starting anything.
+
+For every service it shows:
+
+- `host` (when set)
+- `type`, marked `explicit` when set in azure.yaml or `inferred` when derived from the service shape
+- `language`, `project`, `command`, and `image` (when set)
+- `ports` and `uses` (when set)
+- `configured`: the optional blocks present on the service
+
+The optional blocks reported are `docker`, `healthcheck`, `restart`,
+`resources`, `logs`, `local`, and `azure`.
+
+## Flags
+
+| Flag | Description |
+|------|-------------|
+| `-o, --output` | Output format (default, json) |
+
+## Examples
+
+### Configuration for every service
+
+```bash
+azd app config
+```
+
+### Configuration for a single service
+
+```bash
+azd app config api
+```
+
+### JSON object keyed by service name
+
+```bash
+azd app config --output json
+```
+
+## Notes
+
+- Passing an unknown service name returns an error that lists the available services.
+- `--output json` emits an object keyed by service name, which pairs well with tools like `jq`.
+- Service-level hooks are not part of the azure.yaml schema. Lifecycle hooks are defined at the project level.

cli/src/cmd/app/commands/config.go

@@ -0,0 +1,209 @@
+package commands
+
+import (
+	"fmt"
+	"os"
+	"sort"
+	"strings"
+
+	"github.com/jongio/azd-app/cli/src/internal/service"
+	"github.com/jongio/azd-core/cliout"
+
+	"github.com/spf13/cobra"
+)
+
+// NewConfigCommand creates the config command.
+func NewConfigCommand() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "config [service]",
+		Short: "Show the effective configuration for each service",
+		Long: `Print the configuration azd app resolved from azure.yaml for each service.
+
+For every service this shows the host, the effective service type (explicit or
+inferred), language, project path, run command, image, ports, and dependencies
+(uses), plus which optional blocks are configured (docker, healthcheck, restart,
+resources, logs, local, azure).
+
+Run without arguments to print every service, or pass a service name to print
+just that one. Use --output json for a machine-readable object keyed by service
+name.
+
+Examples:
+  # Configuration for every service
+  azd app config
+
+  # Configuration for a single service
+  azd app config api
+
+  # JSON object keyed by service name
+  azd app config --output json`,
+		SilenceUsage:      true,
+		Args:              cobra.MaximumNArgs(1),
+		RunE:              runConfig,
+		ValidArgsFunction: completeServiceArgs,
+	}
+
+	return cmd
+}
+
+// serviceConfig is the resolved configuration for a single service. In JSON
+// output it is the value of a map keyed by service name, so the name itself is
+// not repeated here.
+type serviceConfig struct {
+	Host       string   `json:"host,omitempty"`
+	Type       string   `json:"type"`
+	TypeSource string   `json:"typeSource"` // "explicit" when set in azure.yaml, otherwise "inferred"
+	Language   string   `json:"language,omitempty"`
+	Project    string   `json:"project,omitempty"`
+	Command    string   `json:"command,omitempty"`
+	Image      string   `json:"image,omitempty"`
+	Ports      []string `json:"ports,omitempty"`
+	Uses       []string `json:"uses,omitempty"`
+	Blocks     []string `json:"blocks,omitempty"` // optional blocks configured on this service
+}
+
+func runConfig(_ *cobra.Command, args []string) error {
+	cwd, err := os.Getwd()
+	if err != nil {
+		return fmt.Errorf("failed to get current directory: %w", err)
+	}
+
+	azureYaml, err := service.ParseAzureYaml(cwd)
+	if err != nil {
+		return fmt.Errorf("failed to load azure.yaml: %w", err)
+	}
+
+	configs, order, err := selectServiceConfigs(azureYaml, args)
+	if err != nil {
+		return err
+	}
+
+	if cliout.IsJSON() {
+		return cliout.PrintJSON(configs)
+	}
+
+	if len(order) == 0 {
+		cliout.Info("No services are defined in azure.yaml")
+		return nil
+	}
+
+	cliout.CommandHeader("config", "Effective service configuration")
+	for i, name := range order {
+		if i > 0 {
+			cliout.Newline()
+		}
+		printServiceConfig(name, configs[name])
+	}
+	return nil
+}
+
+// selectServiceConfigs resolves the configs to display. With no arguments it
+// returns every service in name order; with a single argument it returns just
+// that service, or an error listing the available services when the name is
+// unknown. The returned slice is the display order for text output.
+func selectServiceConfigs(azureYaml *service.AzureYaml, args []string) (map[string]serviceConfig, []string, error) {
+	names := make([]string, 0, len(azureYaml.Services))
+	for name := range azureYaml.Services {
+		names = append(names, name)
+	}
+	sort.Strings(names)
+
+	order := names
+	if len(args) == 1 {
+		name := args[0]
+		if _, ok := azureYaml.Services[name]; !ok {
+			if len(names) == 0 {
+				return nil, nil, fmt.Errorf("service %q not found. No services are defined in azure.yaml", name)
+			}
+			return nil, nil, fmt.Errorf("service %q not found. Available services: %s", name, strings.Join(names, ", "))
+		}
+		order = []string{name}
+	}
+
+	configs := make(map[string]serviceConfig, len(order))
+	for _, name := range order {
+		configs[name] = buildServiceConfig(azureYaml.Services[name])
+	}
+	return configs, order, nil
+}
+
+// buildServiceConfig captures the resolved configuration for a service, using
+// GetServiceType to report the effective type when it is not set explicitly.
+func buildServiceConfig(svc service.Service) serviceConfig {
+	cfg := serviceConfig{
+		Host:     svc.Host,
+		Type:     svc.GetServiceType(),
+		Language: svc.Language,
+		Project:  svc.Project,
+		Command:  svc.Command,
+		Image:    svc.Image,
+		Ports:    svc.Ports,
+		Uses:     svc.Uses,
+		Blocks:   configuredBlocks(svc),
+	}
+	if svc.Type != "" {
+		cfg.TypeSource = "explicit"
+	} else {
+		cfg.TypeSource = "inferred"
+	}
+	return cfg
+}
+
+// configuredBlocks returns the names of the optional service blocks that are set
+// in azure.yaml, in a stable order.
+func configuredBlocks(svc service.Service) []string {
+	var blocks []string
+	if svc.Docker != nil {
+		blocks = append(blocks, "docker")
+	}
+	if svc.Healthcheck != nil {
+		blocks = append(blocks, "healthcheck")
+	}
+	if svc.Restart != nil {
+		blocks = append(blocks, "restart")
+	}
+	if svc.Resources != nil {
+		blocks = append(blocks, "resources")
+	}
+	if svc.Logs != nil {
+		blocks = append(blocks, "logs")
+	}
+	if svc.Local != nil {
+		blocks = append(blocks, "local")
+	}
+	if svc.Azure != nil {
+		blocks = append(blocks, "azure")
+	}
+	return blocks
+}
+
+// printServiceConfig writes one service's resolved configuration as aligned
+// label lines, omitting fields that are not set.
+func printServiceConfig(name string, cfg serviceConfig) {
+	cliout.Info("%s", name)
+	if cfg.Host != "" {
+		cliout.Label("host", cfg.Host)
+	}
+	cliout.Label("type", fmt.Sprintf("%s (%s)", cfg.Type, cfg.TypeSource))
+	if cfg.Language != "" {
+		cliout.Label("language", cfg.Language)
+	}
+	if cfg.Project != "" {
+		cliout.Label("project", cfg.Project)
+	}
+	if cfg.Command != "" {
+		cliout.Label("command", cfg.Command)
+	}
+	if cfg.Image != "" {
+		cliout.Label("image", cfg.Image)
+	}
+	if len(cfg.Ports) > 0 {
+		cliout.Label("ports", strings.Join(cfg.Ports, ", "))
+	}
+	if len(cfg.Uses) > 0 {
+		cliout.Label("uses", strings.Join(cfg.Uses, ", "))
+	}
+	if len(cfg.Blocks) > 0 {
+		cliout.Label("configured", strings.Join(cfg.Blocks, ", "))
+	}
+}