Add new run types for Runnables (#8488)

- allow overriding run_type in on_chain_start

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libs/langchain/langchain/callbacks/tracers/base.py

@@ -227,6 +227,7 @@ class BaseTracer(BaseCallbackHandler, ABC):
         tags: Optional[List[str]] = None,
         parent_run_id: Optional[UUID] = None,
         metadata: Optional[Dict[str, Any]] = None,
+        run_type: Optional[str] = None,
         **kwargs: Any,
     ) -> None:
         """Start a trace for a chain run."""
@@ -246,7 +247,7 @@ class BaseTracer(BaseCallbackHandler, ABC):
             execution_order=execution_order,
             child_execution_order=execution_order,
             child_runs=[],
-            run_type="chain",
+            run_type=run_type or "chain",
             tags=tags or [],
         )
         self._start_trace(chain_run)
@@ -259,7 +260,7 @@ class BaseTracer(BaseCallbackHandler, ABC):
         if not run_id:
             raise TracerException("No run_id provided for on_chain_end callback.")
         chain_run = self.run_map.get(str(run_id))
-        if chain_run is None or chain_run.run_type != "chain":
+        if chain_run is None:
             raise TracerException("No chain Run found to be traced")
 
         chain_run.outputs = outputs
@@ -279,7 +280,7 @@ class BaseTracer(BaseCallbackHandler, ABC):
         if not run_id:
             raise TracerException("No run_id provided for on_chain_error callback.")
         chain_run = self.run_map.get(str(run_id))
-        if chain_run is None or chain_run.run_type != "chain":
+        if chain_run is None:
             raise TracerException("No chain Run found to be traced")
 
         chain_run.error = repr(error)

libs/langchain/langchain/schema/output_parser.py

@@ -41,12 +41,14 @@ class BaseGenerationOutputParser(
                 ),
                 input,
                 config,
+                run_type="parser",
             )
         else:
             return self._call_with_config(
                 lambda inner_input: self.parse_result([Generation(text=inner_input)]),
                 input,
                 config,
+                run_type="parser",
             )
 
 
@@ -87,12 +89,14 @@ class BaseOutputParser(BaseLLMOutputParser, Runnable[Union[str, BaseMessage], T]
                 ),
                 input,
                 config,
+                run_type="parser",
             )
         else:
             return self._call_with_config(
                 lambda inner_input: self.parse_result([Generation(text=inner_input)]),
                 input,
                 config,
+                run_type="parser",
             )
 
     def parse_result(self, result: List[Generation]) -> T:

libs/langchain/langchain/schema/prompt_template.py

@@ -37,7 +37,10 @@ class BasePromptTemplate(Serializable, Runnable[Dict, PromptValue], ABC):
 
     def invoke(self, input: Dict, config: RunnableConfig | None = None) -> PromptValue:
         return self._call_with_config(
-            lambda inner_input: self.format_prompt(**inner_input), input, config
+            lambda inner_input: self.format_prompt(**inner_input),
+            input,
+            config,
+            run_type="prompt",
         )
 
     @abstractmethod

libs/langchain/langchain/schema/runnable.py

@@ -163,6 +163,7 @@ class Runnable(Generic[Input, Output], ABC):
         func: Callable[[Input], Output],
         input: Input,
         config: Optional[RunnableConfig],
+        run_type: Optional[str] = None,
     ) -> Output:
         from langchain.callbacks.manager import CallbackManager
 
@@ -173,7 +174,9 @@ class Runnable(Generic[Input, Output], ABC):
             inheritable_metadata=config.get("metadata"),
         )
         run_manager = callback_manager.on_chain_start(
-            dumpd(self), input if isinstance(input, dict) else {"input": input}
+            dumpd(self),
+            input if isinstance(input, dict) else {"input": input},
+            run_type=run_type,
         )
         try:
             output = func(input)