forloop metadata variables (#1334)

skyvern/forge/sdk/workflow/context_manager.py

@@ -25,6 +25,9 @@ if TYPE_CHECKING:
 LOG = structlog.get_logger()
 
 
+BlockMetadata = dict[str, str | int | float | bool | dict | list]
+
+
 class WorkflowRunContext:
     parameters: dict[str, PARAMETER_TYPE]
     values: dict[str, Any]
@@ -36,9 +39,12 @@ class WorkflowRunContext:
         workflow_output_parameters: list[OutputParameter],
         context_parameters: list[ContextParameter],
     ) -> None:
+        # key is label name
+        self.blocks_metadata: dict[str, BlockMetadata] = {}
         self.parameters = {}
         self.values = {}
         self.secrets = {}
+
         for parameter, run_parameter in workflow_parameter_tuples:
             if parameter.key in self.parameters:
                 prev_value = self.parameters[parameter.key]
@@ -81,6 +87,15 @@ class WorkflowRunContext:
     def set_value(self, key: str, value: Any) -> None:
         self.values[key] = value
 
+    def update_block_metadata(self, label: str, metadata: BlockMetadata) -> None:
+        if label in self.blocks_metadata:
+            self.blocks_metadata[label].update(metadata)
+            return
+        self.blocks_metadata[label] = metadata
+
+    def get_block_metadata(self, label: str) -> BlockMetadata:
+        return self.blocks_metadata.get(label, BlockMetadata())
+
     def get_original_secret_value_or_none(self, secret_id_or_value: Any) -> Any:
         """
         Get the original secret value from the secrets dict. If the secret id is not found, return None.

skyvern/forge/sdk/workflow/models/block.py

@@ -45,7 +45,7 @@ from skyvern.forge.sdk.api.files import (
 from skyvern.forge.sdk.api.llm.api_handler_factory import LLMAPIHandlerFactory
 from skyvern.forge.sdk.db.enums import TaskType
 from skyvern.forge.sdk.schemas.tasks import Task, TaskOutput, TaskStatus
-from skyvern.forge.sdk.workflow.context_manager import WorkflowRunContext
+from skyvern.forge.sdk.workflow.context_manager import BlockMetadata, WorkflowRunContext
 from skyvern.forge.sdk.workflow.exceptions import (
     InvalidEmailClientConfiguration,
     InvalidFileType,
@@ -140,6 +140,17 @@ class Block(BaseModel, abc.ABC):
             status=status,
         )
 
+    def format_block_parameter_template_from_workflow_run_context(
+        self, potential_template: str, workflow_run_context: WorkflowRunContext
+    ) -> str:
+        if not potential_template:
+            return potential_template
+        template = Template(potential_template)
+
+        template_data = workflow_run_context.values.copy()
+        template_data[self.label] = workflow_run_context.get_block_metadata(self.label)
+        return template.render(template_data)
+
     @classmethod
     def get_subclasses(cls) -> tuple[type["Block"], ...]:
         return tuple(cls.__subclasses__())
@@ -152,15 +163,6 @@ class Block(BaseModel, abc.ABC):
     def get_async_aws_client() -> AsyncAWSClient:
         return app.WORKFLOW_CONTEXT_MANAGER.aws_client
 
-    @staticmethod
-    def format_block_parameter_template_from_workflow_run_context(
-        potential_template: str, workflow_run_context: WorkflowRunContext
-    ) -> str:
-        if not potential_template:
-            return potential_template
-        template = Template(potential_template)
-        return template.render(workflow_run_context.values)
-
     @abc.abstractmethod
     async def execute(self, workflow_run_id: str, **kwargs: dict) -> BlockResult:
         pass
@@ -659,8 +661,15 @@ class ForLoopBlock(Block):
             context_parameters_with_value = self.get_loop_block_context_parameters(workflow_run_id, loop_over_value)
             for context_parameter in context_parameters_with_value:
                 workflow_run_context.set_value(context_parameter.key, context_parameter.value)
+
             each_loop_output_values: list[dict[str, Any]] = []
             for block_idx, loop_block in enumerate(self.loop_blocks):
+                metadata: BlockMetadata = {
+                    "current_index": loop_idx,
+                    "current_value": loop_over_value,
+                }
+                workflow_run_context.update_block_metadata(loop_block.label, metadata)
+
                 original_loop_block = loop_block
                 loop_block = loop_block.copy()
                 current_block = loop_block