chore: add retry functionality in the systemDb connection

Author: AayushSaini101

dbos/dbos.go

@@ -101,15 +101,15 @@ type DBOSContext interface {
 	Shutdown(timeout time.Duration) // Gracefully shutdown all DBOS runtime components with ordered cleanup sequence
 
 	// Workflow operations
-	RunAsStep(_ DBOSContext, fn StepFunc, opts ...StepOption) (any, error)                                        // Execute a function as a durable step within a workflow
+	RunAsStep(_ DBOSContext, fn StepFunc, opts ...StepOption) (any, error)                                      // Execute a function as a durable step within a workflow
 	RunWorkflow(_ DBOSContext, fn WorkflowFunc, input any, opts ...WorkflowOption) (WorkflowHandle[any], error) // Start a new workflow execution
-	Send(_ DBOSContext, destinationID string, message any, topic string) error                                    // Send a message to another workflow
-	Recv(_ DBOSContext, topic string, timeout time.Duration) (any, error)                                         // Receive a message sent to this workflow
-	SetEvent(_ DBOSContext, key string, message any) error                                                        // Set a key-value event for this workflow
-	GetEvent(_ DBOSContext, targetWorkflowID string, key string, timeout time.Duration) (any, error)              // Get a key-value event from a target workflow
-	Sleep(_ DBOSContext, duration time.Duration) (time.Duration, error)                                           // Durable sleep that survives workflow recovery
-	GetWorkflowID() (string, error)                                                                               // Get the current workflow ID (only available within workflows)
-	GetStepID() (int, error)                                                                                      // Get the current step ID (only available within workflows)
+	Send(_ DBOSContext, destinationID string, message any, topic string) error                                  // Send a message to another workflow
+	Recv(_ DBOSContext, topic string, timeout time.Duration) (any, error)                                       // Receive a message sent to this workflow
+	SetEvent(_ DBOSContext, key string, message any) error                                                      // Set a key-value event for this workflow
+	GetEvent(_ DBOSContext, targetWorkflowID string, key string, timeout time.Duration) (any, error)            // Get a key-value event from a target workflow
+	Sleep(_ DBOSContext, duration time.Duration) (time.Duration, error)                                         // Durable sleep that survives workflow recovery
+	GetWorkflowID() (string, error)                                                                             // Get the current workflow ID (only available within workflows)
+	GetStepID() (int, error)                                                                                    // Get the current step ID (only available within workflows)
 
 	// Workflow management
 	RetrieveWorkflow(_ DBOSContext, workflowID string) (WorkflowHandle[any], error)                                       // Get a handle to an existing workflow
@@ -317,12 +317,28 @@ func NewDBOSContext(inputConfig Config) (DBOSContext, error) {
 	initExecutor.executorID = config.ExecutorID
 
 	initExecutor.applicationID = os.Getenv("DBOS__APPID")
+	maxRetries := 5
+	retryDelay := time.Second * 2
+
+	var systemDB systemDatabase
+
+	for attempt := 1; attempt <= maxRetries; attempt++ {
+		systemDB, err = newSystemDatabase(initExecutor, config.DatabaseURL, initExecutor.logger)
+		if err == nil {
+			break
+		}
+		initExecutor.logger.Warn("Failed to connect to system DB (attempt %d/%d): %v", attempt, maxRetries, err)
+
+		if attempt < maxRetries {
+			time.Sleep(retryDelay)
+			retryDelay *= 2 // Exponential backoff
+		}
+	}
 
-	// Create the system database
-	systemDB, err := newSystemDatabase(initExecutor, config.DatabaseURL, initExecutor.logger)
 	if err != nil {
-		return nil, newInitializationError(fmt.Sprintf("failed to create system database: %v", err))
+		return nil, newInitializationError(fmt.Sprintf("failed to create system database after %d attempts: %v", maxRetries, err))
 	}
+
 	initExecutor.systemDB = systemDB
 	initExecutor.logger.Info("System database initialized")