AB#2523 Refactor GCP metadata/cloud API (#387)

* Refactor GCP metadata/cloud API

* Remove cloud controller manager from metadata package

* Remove PublicIP

* Move shared cloud packages

* Remove dead code

Signed-off-by: Daniel Weiße <dw@edgeless.systems>

internal/cloud/azureshared/appcredentials.go

@@ -0,0 +1,57 @@
+/*
+Copyright (c) Edgeless Systems GmbH
+
+SPDX-License-Identifier: AGPL-3.0-only
+*/
+
+package azureshared
+
+import (
+	"fmt"
+	"net/url"
+)
+
+// ApplicationCredentials is a set of Azure AD application credentials.
+// It is the equivalent of a service account key in other cloud providers.
+type ApplicationCredentials struct {
+	TenantID          string
+	AppClientID       string
+	ClientSecretValue string
+	Location          string
+}
+
+// ApplicationCredentialsFromURI converts a cloudServiceAccountURI into Azure ApplicationCredentials.
+func ApplicationCredentialsFromURI(cloudServiceAccountURI string) (ApplicationCredentials, error) {
+	uri, err := url.Parse(cloudServiceAccountURI)
+	if err != nil {
+		return ApplicationCredentials{}, err
+	}
+	if uri.Scheme != "serviceaccount" {
+		return ApplicationCredentials{}, fmt.Errorf("invalid service account URI: invalid scheme: %s", uri.Scheme)
+	}
+	if uri.Host != "azure" {
+		return ApplicationCredentials{}, fmt.Errorf("invalid service account URI: invalid host: %s", uri.Host)
+	}
+	query := uri.Query()
+	return ApplicationCredentials{
+		TenantID:          query.Get("tenant_id"),
+		AppClientID:       query.Get("client_id"),
+		ClientSecretValue: query.Get("client_secret"),
+		Location:          query.Get("location"),
+	}, nil
+}
+
+// ToCloudServiceAccountURI converts the ApplicationCredentials into a cloud service account URI.
+func (c ApplicationCredentials) ToCloudServiceAccountURI() string {
+	query := url.Values{}
+	query.Add("tenant_id", c.TenantID)
+	query.Add("client_id", c.AppClientID)
+	query.Add("client_secret", c.ClientSecretValue)
+	query.Add("location", c.Location)
+	uri := url.URL{
+		Scheme:   "serviceaccount",
+		Host:     "azure",
+		RawQuery: query.Encode(),
+	}
+	return uri.String()
+}