api: refactor attestationcfgapi cli

The cli now takes CSP and object kind as argument.
Also made upload an explicit command and the report
path/version an argument.
Previously the report was a flag. The CSP was hardcoded.
There was only one object kind (snp-report).

internal/api/attestationconfigapi/cli/validargs.go

@@ -0,0 +1,53 @@
+/*
+Copyright (c) Edgeless Systems GmbH
+
+SPDX-License-Identifier: AGPL-3.0-only
+*/
+
+package main
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/edgelesssys/constellation/v2/internal/cloud/cloudprovider"
+	"github.com/spf13/cobra"
+)
+
+func isCloudProvider(arg int) cobra.PositionalArgs {
+	return func(cmd *cobra.Command, args []string) error {
+		if provider := cloudprovider.FromString(args[arg]); provider == cloudprovider.Unknown {
+			return fmt.Errorf("argument %s isn't a valid cloud provider", args[arg])
+		}
+		return nil
+	}
+}
+
+func isValidKind(arg int) cobra.PositionalArgs {
+	return func(cmd *cobra.Command, args []string) error {
+		if kind := kindFromString(args[arg]); kind == unknown {
+			return fmt.Errorf("argument %s isn't a valid kind", args[arg])
+		}
+		return nil
+	}
+}
+
+// objectKind encodes the available actions.
+type objectKind string
+
+const (
+	// unknown is the default objectKind and does nothing.
+	unknown       objectKind = "unknown-kind"
+	snpReport     objectKind = "snp-report"
+	guestFirmware objectKind = "guest-firmware"
+)
+
+func kindFromString(s string) objectKind {
+	lower := strings.ToLower(s)
+	switch objectKind(lower) {
+	case snpReport, guestFirmware:
+		return objectKind(lower)
+	default:
+		return unknown
+	}
+}