Move cloud metadata packages and kubernetes resources marshaling to internal

Decouples cloud provider metadata packages from kubernetes related code

Signed-off-by: Malte Poll <mp@edgeless.systems>

internal/cloud/qemu/metadata.go

@@ -0,0 +1,103 @@
+package qemu
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"io"
+	"net/http"
+	"net/url"
+
+	"github.com/edgelesssys/constellation/internal/cloud/metadata"
+)
+
+const qemuMetadataEndpoint = "10.42.0.1:8080"
+
+// Metadata implements core.ProviderMetadata interface for QEMU.
+type Metadata struct{}
+
+// Supported is used to determine if metadata API is implemented for this cloud provider.
+func (m *Metadata) Supported() bool {
+	return true
+}
+
+// List retrieves all instances belonging to the current constellation.
+func (m *Metadata) List(ctx context.Context) ([]metadata.InstanceMetadata, error) {
+	instancesRaw, err := m.retrieveMetadata(ctx, "/peers")
+	if err != nil {
+		return nil, err
+	}
+
+	var instances []metadata.InstanceMetadata
+	err = json.Unmarshal(instancesRaw, &instances)
+	return instances, err
+}
+
+// Self retrieves the current instance.
+func (m *Metadata) Self(ctx context.Context) (metadata.InstanceMetadata, error) {
+	instanceRaw, err := m.retrieveMetadata(ctx, "/self")
+	if err != nil {
+		return metadata.InstanceMetadata{}, err
+	}
+
+	var instance metadata.InstanceMetadata
+	err = json.Unmarshal(instanceRaw, &instance)
+	return instance, err
+}
+
+// GetInstance retrieves an instance using its providerID.
+func (m Metadata) GetInstance(ctx context.Context, providerID string) (metadata.InstanceMetadata, error) {
+	instances, err := m.List(ctx)
+	if err != nil {
+		return metadata.InstanceMetadata{}, err
+	}
+
+	for _, instance := range instances {
+		if instance.ProviderID == providerID {
+			return instance, nil
+		}
+	}
+	return metadata.InstanceMetadata{}, errors.New("instance not found")
+}
+
+// SupportsLoadBalancer returns true if the cloud provider supports load balancers.
+func (m Metadata) SupportsLoadBalancer() bool {
+	return false
+}
+
+// GetLoadBalancerEndpoint returns the endpoint of the load balancer.
+func (m Metadata) GetLoadBalancerEndpoint(ctx context.Context) (string, error) {
+	panic("function *Metadata.GetLoadBalancerEndpoint not implemented")
+}
+
+// UID returns the UID of the constellation.
+func (m Metadata) UID(ctx context.Context) (string, error) {
+	// We expect only one constellation to be deployed in the same QEMU / libvirt environment.
+	// the UID can be an empty string.
+	return "", nil
+}
+
+// GetSubnetworkCIDR retrieves the subnetwork CIDR from cloud provider metadata.
+func (m Metadata) GetSubnetworkCIDR(ctx context.Context) (string, error) {
+	return "10.244.0.0/16", nil
+}
+
+func (m Metadata) retrieveMetadata(ctx context.Context, uri string) ([]byte, error) {
+	url := &url.URL{
+		Scheme: "http",
+		Host:   qemuMetadataEndpoint,
+		Path:   uri,
+	}
+
+	req, err := http.NewRequestWithContext(ctx, http.MethodGet, url.String(), nil)
+	if err != nil {
+		return nil, err
+	}
+	res, err := (&http.Client{}).Do(req)
+	if err != nil {
+		return nil, err
+	}
+	defer res.Body.Close()
+
+	return io.ReadAll(res.Body)
+}