config: dynamic attestation configuration through S3 backed API (#1808)

internal/api/versionsapi/cli/main.go

@@ -0,0 +1,100 @@
+/*
+Copyright (c) Edgeless Systems GmbH
+
+SPDX-License-Identifier: AGPL-3.0-only
+*/
+
+/*
+This package provides a CLI tool to interact with the Constellation versions API.
+
+The tool can be used to request information from the API, but also for admin tasks.
+All actions require an authentication against AWS with the common permissions.
+Andministrative tasks like adding or removing versions require further AWS permissions
+as well as permissions to GCP and Azure.
+
+The CLI is commonly used in the CI pipeline. Most actions shouldn't be executed manually
+by a developer. Notice that there is no synchronization on API operations.
+*/
+package main
+
+import (
+	"context"
+	"fmt"
+	"os"
+	"os/signal"
+
+	"github.com/spf13/cobra"
+)
+
+func main() {
+	if err := execute(); err != nil {
+		os.Exit(1)
+	}
+}
+
+func execute() error {
+	rootCmd := newRootCmd()
+	ctx, cancel := signalContext(context.Background(), os.Interrupt)
+	defer cancel()
+	return rootCmd.ExecuteContext(ctx)
+}
+
+func newRootCmd() *cobra.Command {
+	rootCmd := &cobra.Command{
+		Use:              "versionsapi",
+		Short:            "Interact with the Constellation versions API",
+		Long:             "Interact with the Constellation versions API.",
+		PersistentPreRun: preRunRoot,
+	}
+
+	rootCmd.SetOut(os.Stdout)
+
+	rootCmd.PersistentFlags().Bool("verbose", false, "Enable verbose output")
+	rootCmd.PersistentFlags().String("region", "eu-central-1", "AWS region of the API S3 bucket")
+	rootCmd.PersistentFlags().String("bucket", "cdn-constellation-backend", "S3 bucket name of the API")
+	rootCmd.PersistentFlags().String("distribution-id", "E1H77EZTHC3NE4", "CloudFront distribution ID of the API")
+
+	rootCmd.AddCommand(newAddCmd())
+	rootCmd.AddCommand(newLatestCmd())
+	rootCmd.AddCommand(newListCmd())
+	rootCmd.AddCommand(newRemoveCmd())
+
+	return rootCmd
+}
+
+// signalContext returns a context that is canceled on the handed signal.
+// The signal isn't watched after its first occurrence. Call the cancel
+// function to ensure the internal goroutine is stopped and the signal isn't
+// watched any longer.
+func signalContext(ctx context.Context, sig os.Signal) (context.Context, context.CancelFunc) {
+	sigCtx, stop := signal.NotifyContext(ctx, sig)
+	done := make(chan struct{}, 1)
+	stopDone := make(chan struct{}, 1)
+
+	go func() {
+		defer func() { stopDone <- struct{}{} }()
+		defer stop()
+		select {
+		case <-sigCtx.Done():
+			fmt.Println(" Signal caught. Press ctrl+c again to terminate the program immediately.")
+		case <-done:
+		}
+	}()
+
+	cancelFunc := func() {
+		done <- struct{}{}
+		<-stopDone
+	}
+
+	return sigCtx, cancelFunc
+}
+
+func preRunRoot(cmd *cobra.Command, _ []string) {
+	cmd.SilenceUsage = true
+}
+
+func must(err error) {
+	if err != nil {
+		panic(err)
+	}
+}