WIP

burr/core/action.py

@@ -408,6 +408,9 @@ def with_params(self, **kwargs: Any) -> "FunctionBasedAction":
     def run_and_update(self, state: State, **run_kwargs) -> Tuple[dict, State]:
         return self._fn(state, **self._bound_params, **run_kwargs)
 
+    def is_async(self) -> bool:
+        return inspect.iscoroutinefunction(self._fn)
+
 
 def _validate_action_function(fn: Callable):
     """Validates that an action has the signature: (state: State) -> Tuple[dict, State]

burr/core/application.py

@@ -1,5 +1,6 @@
 import collections
 import dataclasses
+import functools
 import logging
 import pprint
 from typing import (
@@ -16,6 +17,7 @@
     Union,
 )
 
+from burr import visibility
 from burr.core.action import (
     Action,
     Condition,
@@ -221,21 +223,30 @@ def __init__(
         self._adapter_set.call_all_lifecycle_hooks_sync(
             "post_application_create", state=self._state, application_graph=self._graph
         )
+        # TODO -- consider adding global inputs + global input factories to the builder
+        self.dependency_factory = {
+            "__tracer": functools.partial(
+                visibility.tracing.TracerFactory, lifecycle_adapters=self._adapter_set
+            )
+        }
 
     def step(self, inputs: Optional[Dict[str, Any]] = None) -> Optional[Tuple[Action, dict, State]]:
         """Performs a single step, advancing the state machine along.
         This returns a tuple of the action that was run, the result of running
         the action, and the new state.
 
         Use this if you just want to do something with the state and not rely on generators.
-        E.G. press forward/backwards, hnuman in the loop, etc... Odds are this is not
+        E.G. press forward/backwards, human in the loop, etc... Odds are this is not
         the method you want -- you'll want iterate() (if you want to see the state/
         results along the way), or run() (if you just want the final state/results).
 
-        :param inputs: Inputs to the action -- this is if this action requires an input that is passed in from the outside world        :param __run_hooks:
+        :param inputs: Inputs to the action -- this is if this action requires an input that is passed in from the outside world
         :return: Tuple[Function, dict, State] -- the function that was just ran, the result of running it, and the new state
         """
-        return self._step(inputs=inputs, _run_hooks=True)
+
+        out = self._step(inputs=inputs, _run_hooks=True)
+        self._increment_sequence_id()
+        return out
 
     def _step(
         self, inputs: Optional[Dict[str, Any]] = None, _run_hooks: bool = True
@@ -247,6 +258,7 @@ def _step(
             return None
         if inputs is None:
             inputs = {}
+        inputs = self._process_inputs(inputs, next_action)
         if _run_hooks:
             self._adapter_set.call_all_lifecycle_hooks_sync(
                 "pre_run_step", action=next_action, state=self._state, inputs=inputs
@@ -283,12 +295,37 @@ def update_internal_state_value(self, new_state: State, next_action: Action) ->
         new_state = new_state.update(
             **{
                 PRIOR_STEP: next_action.name,
-                # make it a string for future proofing
-                SEQUENCE_ID: str(int(self._state.get(SEQUENCE_ID, 0)) + 1),
             }
         )
         return new_state
 
+    def _process_inputs(self, inputs: Dict[str, Any], action: Action) -> Dict[str, Any]:
+        inputs = inputs.copy()
+        processed_inputs = {}
+        for key in list(inputs.keys()):
+            if key in action.inputs:
+                processed_inputs[key] = inputs.pop(key)
+        if len(inputs) > 0:
+            raise ValueError(
+                f"Keys {inputs.keys()} were passed in as inputs to action "
+                f"{action.name}, but not declared by the action as an input! "
+                f"Action needs: {action.inputs}"
+            )
+        missing_inputs = set(action.inputs) - set(processed_inputs.keys())
+        for required_input in list(missing_inputs):
+            # if we can find it in the dependency factory, we'll use that
+            if required_input in self.dependency_factory:
+                processed_inputs[required_input] = self.dependency_factory[required_input](
+                    action, self.sequence_id
+                )
+                missing_inputs.remove(required_input)
+        if len(missing_inputs) > 0:
+            raise ValueError(
+                f"Action {action.name} is missing required inputs: {missing_inputs}. "
+                f"Has inputs: {processed_inputs}"
+            )
+        return processed_inputs
+
     async def astep(self, inputs: Dict[str, Any] = None) -> Optional[Tuple[Action, dict, State]]:
         """Asynchronous version of step.
 
@@ -298,10 +335,11 @@ async def astep(self, inputs: Dict[str, Any] = None) -> Optional[Tuple[Action, d
         :return: Tuple[Function, dict, State] -- the action that was just ran, the result of running it, and the new state
         """
         next_action = self.get_next_action()
-        if inputs is None:
-            inputs = {}
         if next_action is None:
             return None
+        if inputs is None:
+            inputs = {}
+        inputs = self._process_inputs(inputs, next_action)
         await self._adapter_set.call_all_lifecycle_hooks_sync_and_async(
             "pre_run_step", action=next_action, state=self._state, inputs=inputs
         )
@@ -335,6 +373,7 @@ async def astep(self, inputs: Dict[str, Any] = None) -> Optional[Tuple[Action, d
                 "post_run_step", action=next_action, state=new_state, result=result, exception=exc
             )
         self._set_state(new_state)
+        self._increment_sequence_id()
         return next_action, result, new_state
 
     def _clean_iterate_params(
@@ -515,6 +554,9 @@ async def arun(
         """
         prior_action = None
         result = None
+        halt_before, halt_after, inputs = self._clean_iterate_params(
+            halt_before, halt_after, inputs
+        )
         async for prior_action, result, state in self.aiterate(
             halt_before=halt_before, halt_after=halt_after, inputs=inputs
         ):
@@ -647,6 +689,20 @@ def graph(self) -> ApplicationGraph:
         """
         return self._graph
 
+    @property
+    def sequence_id(self) -> Optional[int]:
+        """gives the sequence ID of the current (next) action.
+        This is incremented after every step is taken -- meaning that incremeneting
+        it is the very last action that is done. Any logging, etc... will use the current
+        step's sequence ID
+
+        :return:
+        """
+        return self._state.get(SEQUENCE_ID, 0)
+
+    def _increment_sequence_id(self):
+        self._state = self._state.update(**{SEQUENCE_ID: self.sequence_id + 1})
+
 
 def _assert_set(value: Optional[Any], field: str, method: str):
     if value is None:

burr/lifecycle/base.py

@@ -4,6 +4,7 @@
 if TYPE_CHECKING:
     # type-checking-only for a circular import
     from burr.core import State, Action, ApplicationGraph
+    from burr.visibility import ActionSpan
 
 from burr.lifecycle.internal import lifecycle
 
@@ -113,6 +114,72 @@ def post_application_create(
         pass
 
 
+@lifecycle.base_hook("pre_start_span")
+class PreStartSpanHook(abc.ABC):
+    """Hook that runs before a span is started in the tracing API.
+    This can be either a context manager or a logger."""
+
+    @abc.abstractmethod
+    def pre_start_span(
+        self,
+        *,
+        action: str,
+        action_sequence_id: int,
+        span: "ActionSpan",
+        span_dependencies: list[str],
+        **future_kwargs: Any,
+    ):
+        pass
+
+
+@lifecycle.base_hook("pre_start_span")
+class PreStartSpanHookAsync(abc.ABC):
+    @abc.abstractmethod
+    async def pre_start_span(
+        self,
+        *,
+        action: str,
+        action_sequence_id: int,
+        span: "ActionSpan",
+        span_dependencies: list[str],
+        **future_kwargs: Any,
+    ):
+        pass
+
+
+@lifecycle.base_hook("post_end_span")
+class PostEndSpanHook(abc.ABC):
+    """Hook that runs after a span is ended in the tracing API.
+    This can be either a context manager or a logger."""
+
+    @abc.abstractmethod
+    def post_end_span(
+        self,
+        *,
+        action: str,
+        action_sequence_id: int,
+        span: "ActionSpan",
+        span_dependencies: list[str],
+        **future_kwargs: Any,
+    ):
+        pass
+
+
+@lifecycle.base_hook("post_end_span")
+class PostEndSpanHookAsync(abc.ABC):
+    @abc.abstractmethod
+    async def post_end_span(
+        self,
+        *,
+        action: str,
+        action_sequence_id: int,
+        span: "ActionSpan",
+        span_dependencies: list[str],
+        **future_kwargs: Any,
+    ):
+        pass
+
+
 # THESE ARE NOT IN USE
 # TODO -- implement/decide how to use them
 @lifecycle.base_hook("pre_run_application")
@@ -159,4 +226,8 @@ async def post_run_application(
     PostRunApplicationHook,
     PostRunApplicationHookAsync,
     PostApplicationCreateHook,
+    PreStartSpanHook,
+    PreStartSpanHookAsync,
+    PostEndSpanHook,
+    PostEndSpanHookAsync,
 ]

burr/tracking/common/models.py

@@ -86,6 +86,13 @@ def from_application_graph(application_graph: ApplicationGraph) -> "ApplicationM
         )
 
 
+INPUT_FILTERLIST = {"__tracer"}
+
+
+def _filter_inputs(d: dict) -> dict:
+    return {k: v for k, v in d.items() if k not in INPUT_FILTERLIST}
+
+
 class BeginEntryModel(IdentifyingModel):
     """Pydantic model that represents an entry for the beginning of a step"""
 
@@ -94,6 +101,10 @@ class BeginEntryModel(IdentifyingModel):
     inputs: Dict[str, Any]
     type: str = "begin_entry"
 
+    @field_serializer("inputs")
+    def serialize_inputs(self, inputs):
+        return _serialize_object(_filter_inputs(inputs))
+
 
 def _serialize_object(d: object) -> Union[dict, list, object]:
     if isinstance(d, list):
@@ -104,8 +115,7 @@ def _serialize_object(d: object) -> Union[dict, list, object]:
         return d.model_dump()
     elif hasattr(d, "to_json"):
         return d.to_json()
-    else:
-        return d
+    return d
 
 
 class EndEntryModel(IdentifyingModel):

burr/visibility/__init__.py

@@ -0,0 +1,4 @@
+from burr.visibility.tracing import ActionSpan
+from burr.visibility.tracing import TracerFactory as Tracer
+
+__all__ = ["Tracer", "ActionSpan"]