feat: knowledge pipeline (#25360)

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api/core/workflow/enums.py

@@ -1,4 +1,12 @@
-from enum import StrEnum
+from enum import Enum, StrEnum
+
+
+class NodeState(Enum):
+    """State of a node or edge during workflow execution."""
+
+    UNKNOWN = "unknown"
+    TAKEN = "taken"
+    SKIPPED = "skipped"
 
 
 class SystemVariableKey(StrEnum):
@@ -14,3 +22,116 @@ class SystemVariableKey(StrEnum):
     APP_ID = "app_id"
     WORKFLOW_ID = "workflow_id"
     WORKFLOW_EXECUTION_ID = "workflow_run_id"
+    # RAG Pipeline
+    DOCUMENT_ID = "document_id"
+    ORIGINAL_DOCUMENT_ID = "original_document_id"
+    BATCH = "batch"
+    DATASET_ID = "dataset_id"
+    DATASOURCE_TYPE = "datasource_type"
+    DATASOURCE_INFO = "datasource_info"
+    INVOKE_FROM = "invoke_from"
+
+
+class NodeType(StrEnum):
+    START = "start"
+    END = "end"
+    ANSWER = "answer"
+    LLM = "llm"
+    KNOWLEDGE_RETRIEVAL = "knowledge-retrieval"
+    KNOWLEDGE_INDEX = "knowledge-index"
+    IF_ELSE = "if-else"
+    CODE = "code"
+    TEMPLATE_TRANSFORM = "template-transform"
+    QUESTION_CLASSIFIER = "question-classifier"
+    HTTP_REQUEST = "http-request"
+    TOOL = "tool"
+    DATASOURCE = "datasource"
+    VARIABLE_AGGREGATOR = "variable-aggregator"
+    LEGACY_VARIABLE_AGGREGATOR = "variable-assigner"  # TODO: Merge this into VARIABLE_AGGREGATOR in the database.
+    LOOP = "loop"
+    LOOP_START = "loop-start"
+    LOOP_END = "loop-end"
+    ITERATION = "iteration"
+    ITERATION_START = "iteration-start"  # Fake start node for iteration.
+    PARAMETER_EXTRACTOR = "parameter-extractor"
+    VARIABLE_ASSIGNER = "assigner"
+    DOCUMENT_EXTRACTOR = "document-extractor"
+    LIST_OPERATOR = "list-operator"
+    AGENT = "agent"
+
+
+class NodeExecutionType(StrEnum):
+    """Node execution type classification."""
+
+    EXECUTABLE = "executable"  # Regular nodes that execute and produce outputs
+    RESPONSE = "response"  # Response nodes that stream outputs (Answer, End)
+    BRANCH = "branch"  # Nodes that can choose different branches (if-else, question-classifier)
+    CONTAINER = "container"  # Container nodes that manage subgraphs (iteration, loop, graph)
+    ROOT = "root"  # Nodes that can serve as execution entry points
+
+
+class ErrorStrategy(StrEnum):
+    FAIL_BRANCH = "fail-branch"
+    DEFAULT_VALUE = "default-value"
+
+
+class FailBranchSourceHandle(StrEnum):
+    FAILED = "fail-branch"
+    SUCCESS = "success-branch"
+
+
+class WorkflowType(StrEnum):
+    """
+    Workflow Type Enum for domain layer
+    """
+
+    WORKFLOW = "workflow"
+    CHAT = "chat"
+    RAG_PIPELINE = "rag-pipeline"
+
+
+class WorkflowExecutionStatus(StrEnum):
+    RUNNING = "running"
+    SUCCEEDED = "succeeded"
+    FAILED = "failed"
+    STOPPED = "stopped"
+    PARTIAL_SUCCEEDED = "partial-succeeded"
+
+
+class WorkflowNodeExecutionMetadataKey(StrEnum):
+    """
+    Node Run Metadata Key.
+    """
+
+    TOTAL_TOKENS = "total_tokens"
+    TOTAL_PRICE = "total_price"
+    CURRENCY = "currency"
+    TOOL_INFO = "tool_info"
+    AGENT_LOG = "agent_log"
+    ITERATION_ID = "iteration_id"
+    ITERATION_INDEX = "iteration_index"
+    LOOP_ID = "loop_id"
+    LOOP_INDEX = "loop_index"
+    PARALLEL_ID = "parallel_id"
+    PARALLEL_START_NODE_ID = "parallel_start_node_id"
+    PARENT_PARALLEL_ID = "parent_parallel_id"
+    PARENT_PARALLEL_START_NODE_ID = "parent_parallel_start_node_id"
+    PARALLEL_MODE_RUN_ID = "parallel_mode_run_id"
+    ITERATION_DURATION_MAP = "iteration_duration_map"  # single iteration duration if iteration node runs
+    LOOP_DURATION_MAP = "loop_duration_map"  # single loop duration if loop node runs
+    ERROR_STRATEGY = "error_strategy"  # node in continue on error mode return the field
+    LOOP_VARIABLE_MAP = "loop_variable_map"  # single loop variable output
+    DATASOURCE_INFO = "datasource_info"
+
+
+class WorkflowNodeExecutionStatus(StrEnum):
+    PENDING = "pending"  # Node is scheduled but not yet executing
+    RUNNING = "running"
+    SUCCEEDED = "succeeded"
+    FAILED = "failed"
+    EXCEPTION = "exception"
+    STOPPED = "stopped"
+    PAUSED = "paused"
+
+    # Legacy statuses - kept for backward compatibility
+    RETRY = "retry"  # Legacy: replaced by retry mechanism in error handling