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/azure/imds_test.go

@@ -0,0 +1,120 @@
+package azure
+
+import (
+	"context"
+	"encoding/json"
+	"fmt"
+	"net"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
+	"google.golang.org/grpc/test/bufconn"
+)
+
+func TestRetrieve(t *testing.T) {
+	response := metadataResponse{
+		Compute: struct {
+			ResourceID string `json:"resourceId,omitempty"`
+		}{
+			ResourceID: "resource-id",
+		},
+	}
+	testCases := map[string]struct {
+		server       httpBufconnServer
+		wantErr      bool
+		wantResponse metadataResponse
+	}{
+		"metadata response parsed": {
+			server:       newHTTPBufconnServerWithMetadataResponse(response),
+			wantResponse: response,
+		},
+		"invalid imds response detected": {
+			server: newHTTPBufconnServer(func(writer http.ResponseWriter, request *http.Request) {
+				fmt.Fprintln(writer, "invalid-result")
+			}),
+			wantErr: true,
+		},
+	}
+
+	for name, tc := range testCases {
+		t.Run(name, func(t *testing.T) {
+			assert := assert.New(t)
+			require := require.New(t)
+
+			defer tc.server.Close()
+
+			hClient := http.Client{
+				Transport: &http.Transport{
+					DialContext:    tc.server.DialContext,
+					Dial:           tc.server.Dial,
+					DialTLSContext: tc.server.DialContext,
+					DialTLS:        tc.server.Dial,
+				},
+			}
+			iClient := imdsClient{
+				client: &hClient,
+			}
+			resp, err := iClient.Retrieve(context.Background())
+
+			if tc.wantErr {
+				assert.Error(err)
+				return
+			}
+			require.NoError(err)
+			assert.Equal(tc.wantResponse, resp)
+		})
+	}
+}
+
+type httpBufconnServer struct {
+	*httptest.Server
+	*bufconn.Listener
+}
+
+func (s *httpBufconnServer) DialContext(ctx context.Context, network, addr string) (net.Conn, error) {
+	return s.Listener.DialContext(ctx)
+}
+
+func (s *httpBufconnServer) Dial(network, addr string) (net.Conn, error) {
+	return s.Listener.Dial()
+}
+
+func (s *httpBufconnServer) Close() {
+	s.Server.Close()
+	s.Listener.Close()
+}
+
+func newHTTPBufconnServer(handlerFunc http.HandlerFunc) httpBufconnServer {
+	server := httptest.NewUnstartedServer(handlerFunc)
+	listener := bufconn.Listen(1024)
+	server.Listener = listener
+	server.Start()
+	return httpBufconnServer{
+		Server:   server,
+		Listener: listener,
+	}
+}
+
+func newHTTPBufconnServerWithMetadataResponse(res metadataResponse) httpBufconnServer {
+	return newHTTPBufconnServer(func(writer http.ResponseWriter, request *http.Request) {
+		if request.Host != "169.254.169.254" || request.Header.Get("Metadata") != "True" || request.URL.Query().Get("format") != "json" || request.URL.Query().Get("api-version") != imdsAPIVersion {
+			writer.WriteHeader(http.StatusInternalServerError)
+			_, err := writer.Write([]byte("error"))
+			if err != nil {
+				panic(err)
+			}
+			return
+		}
+		rawResp, err := json.Marshal(res)
+		if err != nil {
+			panic(err)
+		}
+		_, err = writer.Write(rawResp)
+		if err != nil {
+			panic(err)
+		}
+	})
+}