Introduce ModalExecutionMode enum for execution modes

Author: htahir1

src/zenml/integrations/modal/flavors/modal_orchestrator_flavor.py

@@ -13,6 +13,7 @@
 #  permissions and limitations under the License.
 """Modal orchestrator flavor."""
 
+from enum import Enum
 from typing import TYPE_CHECKING, Optional, Type
 
 from pydantic import SecretStr
@@ -26,6 +27,18 @@
 MODAL_ORCHESTRATOR_FLAVOR = "modal"
 
 
+class ModalExecutionMode(str, Enum):
+    """Execution modes for the Modal orchestrator.
+
+    Attributes:
+        PIPELINE: Execute entire pipeline in one Modal function (fastest, default).
+        PER_STEP: Execute each step in a separate Modal function (granular control).
+    """
+
+    PIPELINE = "pipeline"
+    PER_STEP = "per_step"
+
+
 class ModalOrchestratorSettings(BaseSettings):
     """Modal orchestrator settings.
 
@@ -38,7 +51,7 @@ class ModalOrchestratorSettings(BaseSettings):
         timeout: Maximum execution time in seconds (default 24h).
         min_containers: Minimum containers to keep warm (replaces keep_warm).
         max_containers: Maximum concurrent containers (replaces concurrency_limit).
-        execution_mode: Execution mode - "pipeline" (default, fastest) or "per_step" (granular control).
+        execution_mode: Execution mode - PIPELINE (default, fastest) or PER_STEP (granular control).
         synchronous: Wait for completion (True) or fire-and-forget (False).
         app_warming_window_hours: Hours for app name window to enable container reuse.
             Apps are reused within this time window for efficiency. Default 2 hours.
@@ -53,7 +66,9 @@ class ModalOrchestratorSettings(BaseSettings):
         1  # Keep 1 container warm for sequential execution
     )
     max_containers: Optional[int] = 10  # Allow up to 10 concurrent containers
-    execution_mode: str = "pipeline"  # Default to fastest mode
+    execution_mode: ModalExecutionMode = (
+        ModalExecutionMode.PIPELINE
+    )  # Default to fastest mode
     synchronous: bool = (
         True  # Wait for completion (True) or fire-and-forget (False)
     )

src/zenml/integrations/modal/orchestrators/modal_orchestrator.py

@@ -64,6 +64,12 @@
         ModalOrchestratorConfig,
         ModalOrchestratorSettings,
     )
+
+from zenml.integrations.modal.flavors.modal_orchestrator_flavor import (
+    ModalExecutionMode,
+)
+
+if TYPE_CHECKING:
     from zenml.models import PipelineDeploymentResponse, PipelineRunResponse
     from zenml.models.v2.core.pipeline_deployment import PipelineDeploymentBase
 
@@ -335,7 +341,7 @@ def prepare_or_run_pipeline(
 
         # Create the execution function based on execution mode
         execution_mode = settings.execution_mode or self.config.execution_mode
-        if execution_mode == "per_step":
+        if execution_mode == ModalExecutionMode.PER_STEP:
             logger.debug("Creating per-step mode for granular execution")
             execution_func: Any = run_step_in_modal
             function_name = "run_step_in_modal"
@@ -345,7 +351,7 @@ def prepare_or_run_pipeline(
             function_name = "run_entire_pipeline"
 
         # Get or deploy persistent Modal app with warm containers
-        mode_suffix = execution_mode.replace("_", "-")
+        mode_suffix = execution_mode.value.replace("_", "-")
         app_name_base = f"zenml-{deployment.pipeline_configuration.name.replace('_', '-')}-{mode_suffix}"
 
         execute_step, full_app_name = get_or_deploy_persistent_modal_app(
@@ -406,7 +412,7 @@ def execute_modal_function(
                 )
                 return function_call
 
-        if execution_mode == "per_step":
+        if execution_mode == ModalExecutionMode.PER_STEP:
             logger.info("Using per-step mode for granular execution")
             # Execute steps individually
             for step_name in step_names: