Migrate maintained examples to invocation reporting

integrations/ckconfig/examples/simple/main.go

@@ -3,6 +3,7 @@ package main
 import (
 	"context"
 	"fmt"
+	"io"
 	"os"
 	"strconv"
 
@@ -12,6 +13,9 @@ import (
 )
 
 type appConfiguration struct {
+	Schema struct {
+		Version int `yaml:"version"`
+	} `yaml:"schema"`
 	Greeting string `yaml:"greeting"`
 }
 
@@ -22,12 +26,25 @@ type greetInput struct {
 
 func loadAppConfiguration(_ context.Context, selection ckconfig.Selection) (*configkit.Result[appConfiguration], error) {
 	source := configkit.Mapping("simple application settings", map[string]any{
+		"schema":   map[string]any{"version": 2},
 		"greeting": "Hello",
 	})
 	if selection.Config.Set {
 		source = configkit.File(selection.Config.Value)
 	}
-	options := configkit.Options[appConfiguration]{}
+	options := configkit.Options[appConfiguration]{
+		Definition: configkit.Definition[appConfiguration]{
+			Version: &configkit.VersionRule{
+				Path: configkit.Keys("schema", "version"),
+				Check: func(version configkit.Version, validation *configkit.Validation) error {
+					if version.Text == "1" {
+						validation.Warning(configkit.Keys("schema", "version"), "schema version 1 is supported; upgrade to version 2 before the next example release")
+					}
+					return nil
+				},
+			},
+		},
+	}
 	if selection.Overlay.Set {
 		options.Overlay = selection.Overlay.Value
 		options.Filesystem = &configkit.FilesystemContext{Root: ".", BaseDir: "."}
@@ -50,9 +67,10 @@ func newApp() (*commandkit.App, error) {
 			}),
 		},
 		Run: func(invocation commandkit.Invocation, input greetInput) commandkit.Outcome {
+			reporter := invocation.Reporter()
 			configuration, err := loadAppConfiguration(invocation.Context, ckconfig.Selection{})
 			if err != nil {
-				return commandkit.Failure(err)
+				return commandkit.Failure("Could not load application configuration.").WithCause(err)
 			}
 			count := fmt.Sprintf("default %d (not supplied)", input.Count.Value)
 			if input.Count.Set {
@@ -62,9 +80,10 @@ func newApp() (*commandkit.App, error) {
 			if input.Tags.Set {
 				tags = fmt.Sprintf("explicit %v", input.Tags.Value)
 			}
-			if _, err := fmt.Fprintf(invocation.Streams.Out, "%s; count=%s; tags=%s\n", configuration.Config.Greeting, count, tags); err != nil {
-				return commandkit.Failure(err)
-			}
+			_ = reporter.RenderOutput(func(writer io.Writer) error {
+				_, err := fmt.Fprintf(writer, "%s; count=%s; tags=%s\n", configuration.Config.Greeting, count, tags)
+				return err
+			})
 			return commandkit.Success()
 		},
 	})