chore(verify): verifies region versions

Verify will retrieve the latest regions version and if has the same
version.

cmd/root.go

@@ -88,7 +88,7 @@ func newCmd() *cli.App {
 		return nil
 	}
 
-	app.Commands = commands(bumpCmd)
+	app.Commands = commands(bumpCmd, verifyCmd)
 
 	return app
 }

cmd/verify.go

@@ -0,0 +1,69 @@
+/*
+ * Copyright (c) Fabio da Silva Ribeiro <faabiosr@gmail.com>
+ * SPDX-License-Identifier: MIT
+ */
+
+package cmd
+
+import (
+	"errors"
+	"fmt"
+	"slices"
+
+	"github.com/aws/aws-sdk-go-v2/config"
+	"github.com/urfave/cli/v2"
+
+	"github.com/faabiosr/lb/internal"
+)
+
+var verifyCmd = &cli.Command{
+	Name:        "verify",
+	Description: "verifies layer latest versions across regions",
+	Flags: []cli.Flag{
+		&cli.StringSliceFlag{
+			Name:     "regions",
+			Aliases:  []string{"r"},
+			Usage:    "list of regions separated by comma.",
+			Required: true,
+		},
+	},
+	ArgsUsage: "layer-name",
+	Action: func(cc *cli.Context) error {
+		name := cc.Args().First()
+		if name == "" {
+			return errors.New(`required argument "layer-name" not set`)
+		}
+
+		regions := cc.StringSlice("regions")
+		if len(regions) <= 1 {
+			return errors.New(`required flag "regions" must contain at least two regions`)
+		}
+
+		cfg, err := config.LoadDefaultConfig(cc.Context)
+		if err != nil {
+			return fmt.Errorf("failed to load aws config: %w", err)
+		}
+
+		l := internal.LoadLayer(cfg, name)
+
+		versions, err := l.LatestVersions(cc.Context, regions)
+		if err != nil {
+			return err
+		}
+
+		bumped := slices.CompactFunc(versions, func(c, v *internal.Version) bool {
+			return c.Number == v.Number
+		})
+
+		if len(bumped) == 1 && bumped[0].Number == 0 {
+			return errors.New("there are no published versions")
+		}
+
+		if len(bumped) > 1 {
+			return errors.New(`some regions are not bumped`)
+		}
+
+		fmt.Fprintln(cc.App.Writer, "all regions bumped")
+		return nil
+	},
+}