versionsapi: implement latest cmd in cli

Signed-off-by: Paul Meyer <49727155+katexochen@users.noreply.github.com>

internal/versionsapi/cli/latest.go

@@ -0,0 +1,144 @@
+/*
+Copyright (c) Edgeless Systems GmbH
+
+SPDX-License-Identifier: AGPL-3.0-only
+*/
+
+package main
+
+import (
+	"encoding/json"
+	"fmt"
+
+	"github.com/edgelesssys/constellation/v2/internal/logger"
+	"github.com/edgelesssys/constellation/v2/internal/versionsapi"
+	verclient "github.com/edgelesssys/constellation/v2/internal/versionsapi/client"
+	"github.com/spf13/cobra"
+	"go.uber.org/zap/zapcore"
+)
+
+func newLatestCmd() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:   "latest",
+		Short: "Find latest version",
+		Long:  "Find latest version of a ref/stream. The returned version is in short format, if --json flag is not set.",
+		RunE:  runLatest,
+		Args:  cobra.ExactArgs(0),
+	}
+
+	cmd.Flags().String("ref", "-", "Ref to query")
+	cmd.Flags().String("stream", "stable", "Stream to query")
+	cmd.Flags().Bool("json", false, "Whether to output the result as JSON")
+
+	return cmd
+}
+
+func runLatest(cmd *cobra.Command, args []string) error {
+	flags, err := parseLatestFlags(cmd)
+	if err != nil {
+		return err
+	}
+	log := logger.New(logger.PlainLog, flags.logLevel)
+	log.Debugf("Parsed flags: %+v", flags)
+
+	log.Debugf("Validating flags.")
+	if err := flags.validate(); err != nil {
+		return err
+	}
+
+	log.Debugf("Creating versions API client.")
+	client, err := verclient.NewClient(cmd.Context(), flags.region, flags.bucket, flags.distributionID, true, log)
+	if err != nil {
+		return fmt.Errorf("creating client: %w", err)
+	}
+
+	log.Debugf("Requesting latest version.")
+	latest := versionsapi.Latest{
+		Ref:    flags.ref,
+		Stream: flags.stream,
+		Kind:   versionsapi.VersionKindImage,
+	}
+	latest, err = client.FetchVersionLatest(cmd.Context(), latest)
+	if err != nil {
+		return fmt.Errorf("fetching latest version: %w", err)
+	}
+
+	if flags.json {
+		out, err := json.MarshalIndent(latest, "", "  ")
+		if err != nil {
+			return fmt.Errorf("marshaling JSON: %w", err)
+		}
+		fmt.Fprintln(cmd.OutOrStdout(), string(out))
+		return nil
+	}
+
+	fmt.Fprintln(cmd.OutOrStdout(), latest.ShortPath())
+	return nil
+}
+
+type latestFlags struct {
+	ref            string
+	stream         string
+	json           bool
+	region         string
+	bucket         string
+	distributionID string
+	logLevel       zapcore.Level
+}
+
+func (l *latestFlags) validate() error {
+	if err := versionsapi.ValidateRef(l.ref); err != nil {
+		return fmt.Errorf("invalid ref: %w", err)
+	}
+	if err := versionsapi.ValidateStream(l.ref, l.stream); err != nil {
+		return fmt.Errorf("invalid stream: %w", err)
+	}
+
+	return nil
+}
+
+func parseLatestFlags(cmd *cobra.Command) (latestFlags, error) {
+	ref, err := cmd.Flags().GetString("ref")
+	if err != nil {
+		return latestFlags{}, err
+	}
+	ref = versionsapi.CanonicalizeRef(ref)
+	stream, err := cmd.Flags().GetString("stream")
+	if err != nil {
+		return latestFlags{}, err
+	}
+	json, err := cmd.Flags().GetBool("json")
+	if err != nil {
+		return latestFlags{}, err
+	}
+	region, err := cmd.Flags().GetString("region")
+	if err != nil {
+		return latestFlags{}, err
+	}
+	bucket, err := cmd.Flags().GetString("bucket")
+	if err != nil {
+		return latestFlags{}, err
+	}
+	distributionID, err := cmd.Flags().GetString("distribution-id")
+	if err != nil {
+		return latestFlags{}, err
+	}
+	verbose, err := cmd.Flags().GetBool("verbose")
+	if err != nil {
+		return latestFlags{}, err
+	}
+	logLevel := zapcore.InfoLevel
+	if verbose {
+		logLevel = zapcore.DebugLevel
+	}
+
+	return latestFlags{
+		ref:            ref,
+		stream:         stream,
+		json:           json,
+		region:         region,
+		bucket:         bucket,
+		distributionID: distributionID,
+		logLevel:       logLevel,
+	}, nil
+}

internal/versionsapi/cli/main.go

@@ -44,6 +44,7 @@ func newRootCmd() *cobra.Command {
 	rootCmd.PersistentFlags().String("distribution-id", "E1H77EZTHC3NE4", "CloudFront distribution ID of the API")
 
 	rootCmd.AddCommand(newAddCmd())
+	rootCmd.AddCommand(newLatestCmd())
 
 	return rootCmd
 }