CBG-4392: [3.2.3 backport] provide cluster UUID at top level endpoint (…

…#7363)

* CBG-4390: provide cluster UUID at top level endpoint

* update to fix for non persistent config

* fix for rosmar

* remove pre paramatised test

* nit

* move mgtrequest into common function

* updates

* remove unused code

* fix failing test

* update to create separate struct of info for runtime only info

base/bootstrap.go

@@ -44,7 +44,6 @@ type BootstrapConnection interface {
 	// GetDocument retrieves the document with the specified key from the bucket's default collection.
 	// Returns exists=false if key is not found, returns error for any other error.
 	GetDocument(ctx context.Context, bucket, docID string, rv interface{}) (exists bool, err error)
-
 	// Close releases any long-lived connections
 	Close()
 }

base/bucket.go

@@ -378,15 +378,19 @@ func GetServerUUID(ctx context.Context, store CouchbaseBucketStore) (uuid string
 		return "", err
 	}
 
+	return ParseClusterUUID(respBytes)
+}
+
+func ParseClusterUUID(respBytes []byte) (string, error) {
 	var responseJson struct {
-		ServerUUID string `json:"uuid"`
+		UUID string `json:"uuid"`
 	}
 
 	if err := JSONUnmarshal(respBytes, &responseJson); err != nil {
 		return "", err
 	}
 
-	return responseJson.ServerUUID, nil
+	return responseJson.UUID, nil
 }
 
 // Gets the metadata purge interval for the bucket.  First checks for a bucket-specific value.  If not

base/collection.go

@@ -504,31 +504,17 @@ func (b *GocbV2Bucket) MgmtRequest(ctx context.Context, method, uri, contentType
 		return nil, 0, err
 	}
 
-	req, err := http.NewRequest(method, mgmtEp+uri, body)
-	if err != nil {
-		return nil, 0, err
-	}
-
-	if contentType != "" {
-		req.Header.Add("Content-Type", contentType)
-	}
-
+	var username, password string
 	if b.Spec.Auth != nil {
-		username, password, _ := b.Spec.Auth.GetCredentials()
-		req.SetBasicAuth(username, password)
-	}
-	response, err := b.HttpClient(ctx).Do(req)
-	if err != nil {
-		return nil, response.StatusCode, err
+		username, password, _ = b.Spec.Auth.GetCredentials()
 	}
-	defer func() { _ = response.Body.Close() }()
 
-	respBytes, err := io.ReadAll(response.Body)
+	respBytes, statusCode, err := MgmtRequest(b.HttpClient(ctx), mgmtEp, method, uri, contentType, username, password, body)
 	if err != nil {
-		return nil, 0, err
+		return nil, statusCode, err
 	}
 
-	return respBytes, response.StatusCode, nil
+	return respBytes, statusCode, nil
 }
 
 // This prevents Sync Gateway from overflowing gocb's pipeline

base/gocb_utils.go

@@ -13,6 +13,8 @@ import (
 	"crypto/tls"
 	"crypto/x509"
 	"errors"
+	"io"
+	"net/http"
 	"os"
 	"time"
 
@@ -161,3 +163,31 @@ func getRootCAs(ctx context.Context, caCertPath string) (*x509.CertPool, error)
 	}
 	return rootCAs, nil
 }
+
+// MgmtRequest makes a request to the http couchbase management api. This function will read the entire contents of
+// the response and return the output bytes, the status code, and an error.
+func MgmtRequest(client *http.Client, mgmtEp, method, uri, contentType, username, password string, body io.Reader) ([]byte, int, error) {
+	req, err := http.NewRequest(method, mgmtEp+uri, body)
+	if err != nil {
+		return nil, 0, err
+	}
+
+	if contentType != "" {
+		req.Header.Add("Content-Type", contentType)
+	}
+
+	if username != "" {
+		req.SetBasicAuth(username, password)
+	}
+	response, err := client.Do(req)
+	if err != nil {
+		return nil, response.StatusCode, err
+	}
+	defer func() { _ = response.Body.Close() }()
+
+	respBytes, err := io.ReadAll(response.Body)
+	if err != nil {
+		return nil, 0, err
+	}
+	return respBytes, response.StatusCode, nil
+}

rest/admin_api.go

@@ -352,7 +352,13 @@ func (h *handler) handleGetDbConfig() error {
 
 type RunTimeServerConfigResponse struct {
 	*StartupConfig
-	Databases map[string]*DbConfig `json:"databases"`
+	RuntimeInformation `json:"runtime_information"`
+	Databases          map[string]*DbConfig `json:"databases"`
+}
+
+// RuntimeInformation is a struct that holds runtime-only info in without interfering or being lost inside the actual StartupConfig properties.
+type RuntimeInformation struct {
+	ClusterUUID string `json:"cluster_uuid"`
 }
 
 // Get admin config info
@@ -409,6 +415,13 @@ func (h *handler) handleGetConfig() error {
 			}
 		}
 
+		// grab cluster uuid for runtime config
+		clusterUUID, err := h.server.getClusterUUID(h.ctx())
+		if err != nil {
+			base.InfofCtx(h.ctx(), base.KeyConfig, "Could not determine cluster UUID: %s", err)
+		}
+		cfg.ClusterUUID = clusterUUID
+
 		// because loggers can be changed at runtime, we need to work backwards to get the config that would've created the actually running instances
 		cfg.Logging = *base.BuildLoggingConfigFromLoggers(h.server.Config.Logging)
 		cfg.Databases = databaseMap

rest/config_test.go

@@ -3240,3 +3240,64 @@ func TestRoleUpdatedAtField(t *testing.T) {
 	assert.Greater(t, newTime.UnixNano(), currTime.UnixNano())
 	assert.Equal(t, timeCreated.UnixNano(), newCreated.UnixNano())
 }
+
+func TestServerUUIDRuntimeServerConfig(t *testing.T) {
+	testCases := []struct {
+		name             string
+		persistentConfig bool
+	}{
+		{
+			name:             "Persistent config",
+			persistentConfig: true,
+		},
+		{
+			name:             "non persistent config",
+			persistentConfig: false,
+		},
+	}
+
+	for _, testCase := range testCases {
+		t.Run(testCase.name, func(t *testing.T) {
+			rt := NewRestTester(t, &RestTesterConfig{PersistentConfig: testCase.persistentConfig})
+			defer rt.Close()
+
+			// create a db and test code pathway when we have db defined
+			if testCase.persistentConfig {
+				dbConfig := rt.NewDbConfig()
+				RequireStatus(t, rt.CreateDatabase("db", dbConfig), http.StatusCreated)
+			}
+
+			resp := rt.SendAdminRequest(http.MethodGet, "/_config?include_runtime=true", "")
+			RequireStatus(t, resp, http.StatusOK)
+
+			var clusterUUID string
+			config := RunTimeServerConfigResponse{}
+			err := base.JSONUnmarshal(resp.Body.Bytes(), &config)
+			require.NoError(t, err)
+			if base.TestUseCouchbaseServer() {
+				require.Len(t, config.ClusterUUID, 32)
+			} else {
+				require.Empty(t, config.ClusterUUID)
+			}
+			clusterUUID = config.ClusterUUID
+
+			// delete db and attempt to retrieve cluster UUID again to ensure we can still retrieve it
+			resp = rt.SendAdminRequest(http.MethodDelete, "/db/", "")
+			RequireStatus(t, resp, http.StatusOK)
+
+			resp = rt.SendAdminRequest(http.MethodGet, "/_config?include_runtime=true", "")
+			RequireStatus(t, resp, http.StatusOK)
+
+			config = RunTimeServerConfigResponse{}
+			err = base.JSONUnmarshal(resp.Body.Bytes(), &config)
+			require.NoError(t, err)
+			if base.TestUseCouchbaseServer() {
+				require.Len(t, config.ClusterUUID, 32)
+			} else {
+				require.Empty(t, config.ClusterUUID)
+			}
+			assert.Equal(t, clusterUUID, config.ClusterUUID)
+		})
+	}
+
+}

rest/server_context.go

@@ -16,7 +16,6 @@ import (
 	"encoding/json"
 	"errors"
 	"fmt"
-	"io"
 	"net"
 	"net/http"
 	"os"
@@ -2002,20 +2001,8 @@ func doHTTPAuthRequest(ctx context.Context, httpClient *http.Client, username, p
 	retryCount := 0
 
 	worker := func() (shouldRetry bool, err error, value interface{}) {
-		var httpResponse *http.Response
-
 		endpointIdx := retryCount % len(endpoints)
-		req, err := http.NewRequest(method, endpoints[endpointIdx]+path, bytes.NewBuffer(requestBody))
-		if err != nil {
-			return false, err, nil
-		}
-
-		req.SetBasicAuth(username, password)
-
-		httpResponse, err = httpClient.Do(req) // nolint:bodyclose // The body is closed outside of the worker loop
-		if err == nil {
-			return false, nil, httpResponse
-		}
+		responseBody, statusCode, err = base.MgmtRequest(httpClient, endpoints[endpointIdx], method, path, "", username, password, bytes.NewBuffer(requestBody))
 
 		if err, ok := err.(net.Error); ok && err.Timeout() {
 			retryCount++
@@ -2025,27 +2012,12 @@ func doHTTPAuthRequest(ctx context.Context, httpClient *http.Client, username, p
 		return false, err, nil
 	}
 
-	err, result := base.RetryLoop(ctx, "doHTTPAuthRequest", worker, base.CreateSleeperFunc(10, 100))
+	err, _ = base.RetryLoop(ctx, "doHTTPAuthRequest", worker, base.CreateSleeperFunc(10, 100))
 	if err != nil {
 		return 0, nil, err
 	}
 
-	httpResponse, ok := result.(*http.Response)
-	if !ok {
-		return 0, nil, fmt.Errorf("unexpected response type from doHTTPAuthRequest")
-	}
-
-	bodyString, err := io.ReadAll(httpResponse.Body)
-	if err != nil {
-		return 0, nil, err
-	}
-
-	err = httpResponse.Body.Close()
-	if err != nil {
-		return 0, nil, err
-	}
-
-	return httpResponse.StatusCode, bodyString, nil
+	return statusCode, responseBody, nil
 }
 
 // For test use
@@ -2166,3 +2138,32 @@ func getTotalMemory(ctx context.Context) uint64 {
 	}
 	return memory.Total
 }
+
+// getClusterUUID returns the cluster UUID. rosmar does not have a ClusterUUID, so this will return an empty cluster UUID and no error in this case.
+func (sc *ServerContext) getClusterUUID(ctx context.Context) (string, error) {
+	allDbNames := sc.AllDatabaseNames()
+	// we can use db context to retrieve clusterUUID
+	if len(allDbNames) > 0 {
+		db, err := sc.GetDatabase(ctx, allDbNames[0])
+		if err == nil {
+			return db.ServerUUID, nil
+		}
+	}
+	// no cluster uuid for rosmar cluster
+	if base.ServerIsWalrus(sc.Config.Bootstrap.Server) {
+		return "", nil
+	}
+	// request server for cluster uuid
+	eps, client, err := sc.ObtainManagementEndpointsAndHTTPClient()
+	if err != nil {
+		return "", err
+	}
+	statusCode, output, err := doHTTPAuthRequest(ctx, client, sc.Config.Bootstrap.Username, sc.Config.Bootstrap.Password, http.MethodGet, "/pools", eps, nil)
+	if err != nil {
+		return "", err
+	}
+	if statusCode != http.StatusOK {
+		return "", fmt.Errorf("unable to get cluster UUID from server: %s", output)
+	}
+	return base.ParseClusterUUID(output)
+}