Add api end point to print the current database state in VTOrc (#15485)

Signed-off-by: Manan Gupta <manan@planetscale.com>

Author: GuptaManan100

go/test/endtoend/vtorc/api/api_test.go

@@ -93,6 +93,24 @@ func TestAPIEndpoints(t *testing.T) {
 		return response != "null"
 	})
 
+	t.Run("Database State", func(t *testing.T) {
+		// Get database state
+		status, resp, err := utils.MakeAPICall(t, vtorc, "/api/database-state")
+		require.NoError(t, err)
+		assert.Equal(t, 200, status)
+		assert.Contains(t, resp, `"alias": "zone1-0000000101"`)
+		assert.Contains(t, resp, `{
+		"TableName": "vitess_keyspace",
+		"Rows": [
+			{
+				"durability_policy": "none",
+				"keyspace": "ks",
+				"keyspace_type": "0"
+			}
+		]
+	},`)
+	})
+
 	t.Run("Disable Recoveries API", func(t *testing.T) {
 		// Disable recoveries of VTOrc
 		status, resp, err := utils.MakeAPICall(t, vtorc, "/api/disable-global-recoveries")

go/vt/external/golib/sqlutils/sqlutils.go

@@ -42,7 +42,7 @@ type RowMap map[string]CellData
 // CellData is the result of a single (atomic) column in a single row
 type CellData sql.NullString
 
-func (this *CellData) MarshalJSON() ([]byte, error) {
+func (this CellData) MarshalJSON() ([]byte, error) {
 	if this.Valid {
 		return json.Marshal(this.String)
 	} else {

go/vt/vtorc/db/generate_base.go

@@ -16,6 +16,28 @@
 
 package db
 
+var TableNames = []string{
+	"database_instance",
+	"audit",
+	"active_node",
+	"node_health",
+	"topology_recovery",
+	"database_instance_topology_history",
+	"candidate_database_instance",
+	"topology_failure_detection",
+	"blocked_topology_recovery",
+	"database_instance_last_analysis",
+	"database_instance_analysis_changelog",
+	"node_health_history",
+	"vtorc_db_deployments",
+	"global_recovery_disable",
+	"topology_recovery_steps",
+	"database_instance_stale_binlog_coordinates",
+	"vitess_tablet",
+	"vitess_keyspace",
+	"vitess_shard",
+}
+
 // vtorcBackend is a list of SQL statements required to build the vtorc backend
 var vtorcBackend = []string{
 	`

go/vt/vtorc/inst/instance_dao.go

@@ -17,6 +17,7 @@
 package inst
 
 import (
+	"encoding/json"
 	"errors"
 	"fmt"
 	"regexp"
@@ -1210,3 +1211,32 @@ func ExpireStaleInstanceBinlogCoordinates() error {
 	}
 	return ExecDBWriteFunc(writeFunc)
 }
+
+// GetDatabaseState takes the snapshot of the database and returns it.
+func GetDatabaseState() (string, error) {
+	type tableState struct {
+		TableName string
+		Rows      []sqlutils.RowMap
+	}
+
+	var dbState []tableState
+	for _, tableName := range db.TableNames {
+		ts := tableState{
+			TableName: tableName,
+		}
+		err := db.QueryVTOrc("select * from "+tableName, nil, func(rowMap sqlutils.RowMap) error {
+			ts.Rows = append(ts.Rows, rowMap)
+			return nil
+		})
+		if err != nil {
+			return "", err
+		}
+		dbState = append(dbState, ts)
+	}
+	jsonData, err := json.MarshalIndent(dbState, "", "\t")
+	if err != nil {
+		return "", err
+	}
+
+	return string(jsonData), nil
+}

go/vt/vtorc/inst/instance_dao_test.go

@@ -746,3 +746,19 @@ func waitForCacheInitialization() {
 		time.Sleep(100 * time.Millisecond)
 	}
 }
+
+func TestGetDatabaseState(t *testing.T) {
+	// Clear the database after the test. The easiest way to do that is to run all the initialization commands again.
+	defer func() {
+		db.ClearVTOrcDatabase()
+	}()
+
+	for _, query := range initialSQL {
+		_, err := db.ExecVTOrc(query)
+		require.NoError(t, err)
+	}
+
+	ds, err := GetDatabaseState()
+	require.NoError(t, err)
+	require.Contains(t, ds, `"alias": "zone1-0000000112"`)
+}

go/vt/vtorc/server/api.go

@@ -45,6 +45,7 @@ const (
 	disableGlobalRecoveriesAPI    = "/api/disable-global-recoveries"
 	enableGlobalRecoveriesAPI     = "/api/enable-global-recoveries"
 	replicationAnalysisAPI        = "/api/replication-analysis"
+	databaseStateAPI              = "/api/database-state"
 	healthAPI                     = "/debug/health"
 	AggregatedDiscoveryMetricsAPI = "/api/aggregated-discovery-metrics"
 
@@ -60,6 +61,7 @@ var (
 		disableGlobalRecoveriesAPI,
 		enableGlobalRecoveriesAPI,
 		replicationAnalysisAPI,
+		databaseStateAPI,
 		healthAPI,
 		AggregatedDiscoveryMetricsAPI,
 	}
@@ -86,6 +88,8 @@ func (v *vtorcAPI) ServeHTTP(response http.ResponseWriter, request *http.Request
 		errantGTIDsAPIHandler(response, request)
 	case replicationAnalysisAPI:
 		replicationAnalysisAPIHandler(response, request)
+	case databaseStateAPI:
+		databaseStateAPIHandler(response)
 	case AggregatedDiscoveryMetricsAPI:
 		AggregatedDiscoveryMetricsAPIHandler(response, request)
 	default:
@@ -104,7 +108,7 @@ func getACLPermissionLevelForAPI(apiEndpoint string) string {
 		return acl.ADMIN
 	case replicationAnalysisAPI:
 		return acl.MONITORING
-	case healthAPI:
+	case healthAPI, databaseStateAPI:
 		return acl.MONITORING
 	}
 	return acl.ADMIN
@@ -166,6 +170,16 @@ func errantGTIDsAPIHandler(response http.ResponseWriter, request *http.Request)
 	returnAsJSON(response, http.StatusOK, instances)
 }
 
+// databaseStateAPIHandler is the handler for the databaseStateAPI endpoint
+func databaseStateAPIHandler(response http.ResponseWriter) {
+	ds, err := inst.GetDatabaseState()
+	if err != nil {
+		http.Error(response, err.Error(), http.StatusInternalServerError)
+		return
+	}
+	writePlainTextResponse(response, ds, http.StatusOK)
+}
+
 // AggregatedDiscoveryMetricsAPIHandler is the handler for the discovery metrics endpoint
 func AggregatedDiscoveryMetricsAPIHandler(response http.ResponseWriter, request *http.Request) {
 	// return metrics for last x seconds