InvokeAI/invokeai/app/services/graph.py
2023-03-16 20:03:08 +11:00

1131 lines
40 KiB
Python

# Copyright (c) 2022 Kyle Schouviller (https://github.com/kyle0654)
import copy
import itertools
import traceback
import uuid
from types import NoneType
from typing import (
Annotated,
Any,
Literal,
Optional,
Union,
get_args,
get_origin,
get_type_hints,
)
import networkx as nx
from pydantic import BaseModel, validator
from pydantic.fields import Field
from ..invocations import *
from ..invocations.baseinvocation import (
BaseInvocation,
BaseInvocationOutput,
InvocationContext,
)
from .invocation_services import InvocationServices
class EdgeConnection(BaseModel):
node_id: str = Field(description="The id of the node for this edge connection")
field: str = Field(description="The field for this connection")
def __eq__(self, other):
return (
isinstance(other, self.__class__)
and getattr(other, "node_id", None) == self.node_id
and getattr(other, "field", None) == self.field
)
def __hash__(self):
return hash(f"{self.node_id}.{self.field}")
class Edge(BaseModel):
source: EdgeConnection = Field(description="The connection for the edge's from node and field")
destination: EdgeConnection = Field(description="The connection for the edge's to node and field")
def get_output_field(node: BaseInvocation, field: str) -> Any:
node_type = type(node)
node_outputs = get_type_hints(node_type.get_output_type())
node_output_field = node_outputs.get(field) or None
return node_output_field
def get_input_field(node: BaseInvocation, field: str) -> Any:
node_type = type(node)
node_inputs = get_type_hints(node_type)
node_input_field = node_inputs.get(field) or None
return node_input_field
def are_connection_types_compatible(from_type: Any, to_type: Any) -> bool:
if not from_type:
return False
if not to_type:
return False
# TODO: this is pretty forgiving on generic types. Clean that up (need to handle optionals and such)
if from_type and to_type:
# Ports are compatible
if (
from_type == to_type
or from_type == Any
or to_type == Any
or Any in get_args(from_type)
or Any in get_args(to_type)
):
return True
if from_type in get_args(to_type):
return True
if to_type in get_args(from_type):
return True
if not issubclass(from_type, to_type):
return False
else:
return False
return True
def are_connections_compatible(
from_node: BaseInvocation, from_field: str, to_node: BaseInvocation, to_field: str
) -> bool:
"""Determines if a connection between fields of two nodes is compatible."""
# TODO: handle iterators and collectors
from_node_field = get_output_field(from_node, from_field)
to_node_field = get_input_field(to_node, to_field)
return are_connection_types_compatible(from_node_field, to_node_field)
class NodeAlreadyInGraphError(Exception):
pass
class InvalidEdgeError(Exception):
pass
class NodeNotFoundError(Exception):
pass
class NodeAlreadyExecutedError(Exception):
pass
# TODO: Create and use an Empty output?
class GraphInvocationOutput(BaseInvocationOutput):
type: Literal["graph_output"] = "graph_output"
# TODO: Fill this out and move to invocations
class GraphInvocation(BaseInvocation):
type: Literal["graph"] = "graph"
# TODO: figure out how to create a default here
graph: "Graph" = Field(description="The graph to run", default=None)
def invoke(self, context: InvocationContext) -> GraphInvocationOutput:
"""Invoke with provided services and return outputs."""
return GraphInvocationOutput()
class IterateInvocationOutput(BaseInvocationOutput):
"""Used to connect iteration outputs. Will be expanded to a specific output."""
type: Literal["iterate_output"] = "iterate_output"
item: Any = Field(description="The item being iterated over")
# TODO: Fill this out and move to invocations
class IterateInvocation(BaseInvocation):
type: Literal["iterate"] = "iterate"
collection: list[Any] = Field(
description="The list of items to iterate over", default_factory=list
)
index: int = Field(
description="The index, will be provided on executed iterators", default=0
)
def invoke(self, context: InvocationContext) -> IterateInvocationOutput:
"""Produces the outputs as values"""
return IterateInvocationOutput(item=self.collection[self.index])
class CollectInvocationOutput(BaseInvocationOutput):
type: Literal["collect_output"] = "collect_output"
collection: list[Any] = Field(description="The collection of input items")
class CollectInvocation(BaseInvocation):
"""Collects values into a collection"""
type: Literal["collect"] = "collect"
item: Any = Field(
description="The item to collect (all inputs must be of the same type)",
default=None,
)
collection: list[Any] = Field(
description="The collection, will be provided on execution",
default_factory=list,
)
def invoke(self, context: InvocationContext) -> CollectInvocationOutput:
"""Invoke with provided services and return outputs."""
return CollectInvocationOutput(collection=copy.copy(self.collection))
InvocationsUnion = Union[BaseInvocation.get_invocations()] # type: ignore
InvocationOutputsUnion = Union[BaseInvocationOutput.get_all_subclasses_tuple()] # type: ignore
class Graph(BaseModel):
id: str = Field(description="The id of this graph", default_factory=uuid.uuid4)
# TODO: use a list (and never use dict in a BaseModel) because pydantic/fastapi hates me
nodes: dict[str, Annotated[InvocationsUnion, Field(discriminator="type")]] = Field(
description="The nodes in this graph", default_factory=dict
)
edges: list[Edge] = Field(
description="The connections between nodes and their fields in this graph",
default_factory=list,
)
def add_node(self, node: BaseInvocation) -> None:
"""Adds a node to a graph
:raises NodeAlreadyInGraphError: the node is already present in the graph.
"""
if node.id in self.nodes:
raise NodeAlreadyInGraphError()
self.nodes[node.id] = node
def _get_graph_and_node(self, node_path: str) -> tuple["Graph", str]:
"""Returns the graph and node id for a node path."""
# Materialized graphs may have nodes at the top level
if node_path in self.nodes:
return (self, node_path)
node_id = (
node_path if "." not in node_path else node_path[: node_path.index(".")]
)
if node_id not in self.nodes:
raise NodeNotFoundError(f"Node {node_path} not found in graph")
node = self.nodes[node_id]
if not isinstance(node, GraphInvocation):
# There's more node path left but this isn't a graph - failure
raise NodeNotFoundError("Node path terminated early at a non-graph node")
return node.graph._get_graph_and_node(node_path[node_path.index(".") + 1 :])
def delete_node(self, node_path: str) -> None:
"""Deletes a node from a graph"""
try:
graph, node_id = self._get_graph_and_node(node_path)
# Delete edges for this node
input_edges = self._get_input_edges_and_graphs(node_path)
output_edges = self._get_output_edges_and_graphs(node_path)
for edge_graph, _, edge in input_edges:
edge_graph.delete_edge(edge)
for edge_graph, _, edge in output_edges:
edge_graph.delete_edge(edge)
del graph.nodes[node_id]
except NodeNotFoundError:
pass # Ignore, not doesn't exist (should this throw?)
def add_edge(self, edge: Edge) -> None:
"""Adds an edge to a graph
:raises InvalidEdgeError: the provided edge is invalid.
"""
if self._is_edge_valid(edge) and edge not in self.edges:
self.edges.append(edge)
else:
raise InvalidEdgeError()
def delete_edge(self, edge: Edge) -> None:
"""Deletes an edge from a graph"""
try:
self.edges.remove(edge)
except KeyError:
pass
def is_valid(self) -> bool:
"""Validates the graph."""
# Validate all subgraphs
for gn in (n for n in self.nodes.values() if isinstance(n, GraphInvocation)):
if not gn.graph.is_valid():
return False
# Validate all edges reference nodes in the graph
node_ids = set(
[e.source.node_id for e in self.edges] + [e.destination.node_id for e in self.edges]
)
if not all((self.has_node(node_id) for node_id in node_ids)):
return False
# Validate there are no cycles
g = self.nx_graph_flat()
if not nx.is_directed_acyclic_graph(g):
return False
# Validate all edge connections are valid
if not all(
(
are_connections_compatible(
self.get_node(e.source.node_id),
e.source.field,
self.get_node(e.destination.node_id),
e.destination.field,
)
for e in self.edges
)
):
return False
# Validate all iterators
# TODO: may need to validate all iterators in subgraphs so edge connections in parent graphs will be available
if not all(
(
self._is_iterator_connection_valid(n.id)
for n in self.nodes.values()
if isinstance(n, IterateInvocation)
)
):
return False
# Validate all collectors
# TODO: may need to validate all collectors in subgraphs so edge connections in parent graphs will be available
if not all(
(
self._is_collector_connection_valid(n.id)
for n in self.nodes.values()
if isinstance(n, CollectInvocation)
)
):
return False
return True
def _is_edge_valid(self, edge: Edge) -> bool:
"""Validates that a new edge doesn't create a cycle in the graph"""
# Validate that the nodes exist (edges may contain node paths, so we can't just check for nodes directly)
try:
from_node = self.get_node(edge.source.node_id)
to_node = self.get_node(edge.destination.node_id)
except NodeNotFoundError:
return False
# Validate that an edge to this node+field doesn't already exist
input_edges = self._get_input_edges(edge.destination.node_id, edge.destination.field)
if len(input_edges) > 0 and not isinstance(to_node, CollectInvocation):
return False
# Validate that no cycles would be created
g = self.nx_graph_flat()
g.add_edge(edge.source.node_id, edge.destination.node_id)
if not nx.is_directed_acyclic_graph(g):
return False
# Validate that the field types are compatible
if not are_connections_compatible(
from_node, edge.source.field, to_node, edge.destination.field
):
return False
# Validate if iterator output type matches iterator input type (if this edge results in both being set)
if isinstance(to_node, IterateInvocation) and edge.destination.field == "collection":
if not self._is_iterator_connection_valid(
edge.destination.node_id, new_input=edge.source
):
return False
# Validate if iterator input type matches output type (if this edge results in both being set)
if isinstance(from_node, IterateInvocation) and edge.source.field == "item":
if not self._is_iterator_connection_valid(
edge.source.node_id, new_output=edge.destination
):
return False
# Validate if collector input type matches output type (if this edge results in both being set)
if isinstance(to_node, CollectInvocation) and edge.destination.field == "item":
if not self._is_collector_connection_valid(
edge.destination.node_id, new_input=edge.source
):
return False
# Validate if collector output type matches input type (if this edge results in both being set)
if isinstance(from_node, CollectInvocation) and edge.source.field == "collection":
if not self._is_collector_connection_valid(
edge.source.node_id, new_output=edge.destination
):
return False
return True
def has_node(self, node_path: str) -> bool:
"""Determines whether or not a node exists in the graph."""
try:
n = self.get_node(node_path)
if n is not None:
return True
else:
return False
except NodeNotFoundError:
return False
def get_node(self, node_path: str) -> InvocationsUnion:
"""Gets a node from the graph using a node path."""
# Materialized graphs may have nodes at the top level
graph, node_id = self._get_graph_and_node(node_path)
return graph.nodes[node_id]
def _get_node_path(self, node_id: str, prefix: Optional[str] = None) -> str:
return node_id if prefix is None or prefix == "" else f"{prefix}.{node_id}"
def update_node(self, node_path: str, new_node: BaseInvocation) -> None:
"""Updates a node in the graph."""
graph, node_id = self._get_graph_and_node(node_path)
node = graph.nodes[node_id]
# Ensure the node type matches the new node
if type(node) != type(new_node):
raise TypeError(
f"Node {node_path} is type {type(node)} but new node is type {type(new_node)}"
)
# Ensure the new id is either the same or is not in the graph
prefix = None if "." not in node_path else node_path[: node_path.rindex(".")]
new_path = self._get_node_path(new_node.id, prefix=prefix)
if new_node.id != node.id and self.has_node(new_path):
raise NodeAlreadyInGraphError(
"Node with id {new_node.id} already exists in graph"
)
# Set the new node in the graph
graph.nodes[new_node.id] = new_node
if new_node.id != node.id:
input_edges = self._get_input_edges_and_graphs(node_path)
output_edges = self._get_output_edges_and_graphs(node_path)
# Delete node and all edges
graph.delete_node(node_path)
# Create new edges for each input and output
for graph, _, edge in input_edges:
# Remove the graph prefix from the node path
new_graph_node_path = (
new_node.id
if "." not in edge.destination.node_id
else f'{edge.destination.node_id[edge.destination.node_id.rindex("."):]}.{new_node.id}'
)
graph.add_edge(
Edge(
source=edge.source,
destination=EdgeConnection(
node_id=new_graph_node_path, field=edge.destination.field
)
)
)
for graph, _, edge in output_edges:
# Remove the graph prefix from the node path
new_graph_node_path = (
new_node.id
if "." not in edge.source.node_id
else f'{edge.source.node_id[edge.source.node_id.rindex("."):]}.{new_node.id}'
)
graph.add_edge(
Edge(
source=EdgeConnection(
node_id=new_graph_node_path, field=edge.source.field
),
destination=edge.destination
)
)
def _get_input_edges(
self, node_path: str, field: Optional[str] = None
) -> list[Edge]:
"""Gets all input edges for a node"""
edges = self._get_input_edges_and_graphs(node_path)
# Filter to edges that match the field
filtered_edges = (e for e in edges if field is None or e[2].destination.field == field)
# Create full node paths for each edge
return [
Edge(
source=EdgeConnection(
node_id=self._get_node_path(e.source.node_id, prefix=prefix),
field=e.source.field,
),
destination=EdgeConnection(
node_id=self._get_node_path(e.destination.node_id, prefix=prefix),
field=e.destination.field,
)
)
for _, prefix, e in filtered_edges
]
def _get_input_edges_and_graphs(
self, node_path: str, prefix: Optional[str] = None
) -> list[tuple["Graph", str, Edge]]:
"""Gets all input edges for a node along with the graph they are in and the graph's path"""
edges = list()
# Return any input edges that appear in this graph
edges.extend(
[(self, prefix, e) for e in self.edges if e.destination.node_id == node_path]
)
node_id = (
node_path if "." not in node_path else node_path[: node_path.index(".")]
)
node = self.nodes[node_id]
if isinstance(node, GraphInvocation):
graph = node.graph
graph_path = (
node.id
if prefix is None or prefix == ""
else self._get_node_path(node.id, prefix=prefix)
)
graph_edges = graph._get_input_edges_and_graphs(
node_path[(len(node_id) + 1) :], prefix=graph_path
)
edges.extend(graph_edges)
return edges
def _get_output_edges(
self, node_path: str, field: str
) -> list[Edge]:
"""Gets all output edges for a node"""
edges = self._get_output_edges_and_graphs(node_path)
# Filter to edges that match the field
filtered_edges = (e for e in edges if e[2].source.field == field)
# Create full node paths for each edge
return [
Edge(
source=EdgeConnection(
node_id=self._get_node_path(e.source.node_id, prefix=prefix),
field=e.source.field,
),
destination=EdgeConnection(
node_id=self._get_node_path(e.destination.node_id, prefix=prefix),
field=e.destination.field,
)
)
for _, prefix, e in filtered_edges
]
def _get_output_edges_and_graphs(
self, node_path: str, prefix: Optional[str] = None
) -> list[tuple["Graph", str, Edge]]:
"""Gets all output edges for a node along with the graph they are in and the graph's path"""
edges = list()
# Return any input edges that appear in this graph
edges.extend(
[(self, prefix, e) for e in self.edges if e.source.node_id == node_path]
)
node_id = (
node_path if "." not in node_path else node_path[: node_path.index(".")]
)
node = self.nodes[node_id]
if isinstance(node, GraphInvocation):
graph = node.graph
graph_path = (
node.id
if prefix is None or prefix == ""
else self._get_node_path(node.id, prefix=prefix)
)
graph_edges = graph._get_output_edges_and_graphs(
node_path[(len(node_id) + 1) :], prefix=graph_path
)
edges.extend(graph_edges)
return edges
def _is_iterator_connection_valid(
self,
node_path: str,
new_input: Optional[EdgeConnection] = None,
new_output: Optional[EdgeConnection] = None,
) -> bool:
inputs = list([e.source for e in self._get_input_edges(node_path, "collection")])
outputs = list([e.destination for e in self._get_output_edges(node_path, "item")])
if new_input is not None:
inputs.append(new_input)
if new_output is not None:
outputs.append(new_output)
# Only one input is allowed for iterators
if len(inputs) > 1:
return False
# Get input and output fields (the fields linked to the iterator's input/output)
input_field = get_output_field(
self.get_node(inputs[0].node_id), inputs[0].field
)
output_fields = list(
[get_input_field(self.get_node(e.node_id), e.field) for e in outputs]
)
# Input type must be a list
if get_origin(input_field) != list:
return False
# Validate that all outputs match the input type
input_field_item_type = get_args(input_field)[0]
if not all(
(
are_connection_types_compatible(input_field_item_type, f)
for f in output_fields
)
):
return False
return True
def _is_collector_connection_valid(
self,
node_path: str,
new_input: Optional[EdgeConnection] = None,
new_output: Optional[EdgeConnection] = None,
) -> bool:
inputs = list([e.source for e in self._get_input_edges(node_path, "item")])
outputs = list([e.destination for e in self._get_output_edges(node_path, "collection")])
if new_input is not None:
inputs.append(new_input)
if new_output is not None:
outputs.append(new_output)
# Get input and output fields (the fields linked to the iterator's input/output)
input_fields = list(
[get_output_field(self.get_node(e.node_id), e.field) for e in inputs]
)
output_fields = list(
[get_input_field(self.get_node(e.node_id), e.field) for e in outputs]
)
# Validate that all inputs are derived from or match a single type
input_field_types = set(
[
t
for input_field in input_fields
for t in (
[input_field]
if get_origin(input_field) == None
else get_args(input_field)
)
if t != NoneType
]
) # Get unique types
type_tree = nx.DiGraph()
type_tree.add_nodes_from(input_field_types)
type_tree.add_edges_from(
[
e
for e in itertools.permutations(input_field_types, 2)
if issubclass(e[1], e[0])
]
)
type_degrees = type_tree.in_degree(type_tree.nodes)
if sum((t[1] == 0 for t in type_degrees)) != 1: # type: ignore
return False # There is more than one root type
# Get the input root type
input_root_type = next(t[0] for t in type_degrees if t[1] == 0) # type: ignore
# Verify that all outputs are lists
if not all((get_origin(f) == list for f in output_fields)):
return False
# Verify that all outputs match the input type (are a base class or the same class)
if not all(
(issubclass(input_root_type, get_args(f)[0]) for f in output_fields)
):
return False
return True
def nx_graph(self) -> nx.DiGraph:
"""Returns a NetworkX DiGraph representing the layout of this graph"""
# TODO: Cache this?
g = nx.DiGraph()
g.add_nodes_from([n for n in self.nodes.keys()])
g.add_edges_from(set([(e.source.node_id, e.destination.node_id) for e in self.edges]))
return g
def nx_graph_flat(
self, nx_graph: Optional[nx.DiGraph] = None, prefix: Optional[str] = None
) -> nx.DiGraph:
"""Returns a flattened NetworkX DiGraph, including all subgraphs (but not with iterations expanded)"""
g = nx_graph or nx.DiGraph()
# Add all nodes from this graph except graph/iteration nodes
g.add_nodes_from(
[
self._get_node_path(n.id, prefix)
for n in self.nodes.values()
if not isinstance(n, GraphInvocation)
and not isinstance(n, IterateInvocation)
]
)
# Expand graph nodes
for sgn in (
gn for gn in self.nodes.values() if isinstance(gn, GraphInvocation)
):
sgn.graph.nx_graph_flat(g, self._get_node_path(sgn.id, prefix))
# TODO: figure out if iteration nodes need to be expanded
unique_edges = set([(e.source.node_id, e.destination.node_id) for e in self.edges])
g.add_edges_from(
[
(self._get_node_path(e[0], prefix), self._get_node_path(e[1], prefix))
for e in unique_edges
]
)
return g
class GraphExecutionState(BaseModel):
"""Tracks the state of a graph execution"""
id: str = Field(
description="The id of the execution state", default_factory=uuid.uuid4
)
# TODO: Store a reference to the graph instead of the actual graph?
graph: Graph = Field(description="The graph being executed")
# The graph of materialized nodes
execution_graph: Graph = Field(
description="The expanded graph of activated and executed nodes",
default_factory=Graph,
)
# Nodes that have been executed
executed: set[str] = Field(
description="The set of node ids that have been executed", default_factory=set
)
executed_history: list[str] = Field(
description="The list of node ids that have been executed, in order of execution",
default_factory=list,
)
# The results of executed nodes
results: dict[
str, Annotated[InvocationOutputsUnion, Field(discriminator="type")]
] = Field(description="The results of node executions", default_factory=dict)
# Errors raised when executing nodes
errors: dict[str, str] = Field(
description="Errors raised when executing nodes", default_factory=dict
)
# Map of prepared/executed nodes to their original nodes
prepared_source_mapping: dict[str, str] = Field(
description="The map of prepared nodes to original graph nodes",
default_factory=dict,
)
# Map of original nodes to prepared nodes
source_prepared_mapping: dict[str, set[str]] = Field(
description="The map of original graph nodes to prepared nodes",
default_factory=dict,
)
# Declare all fields as required; necessary for OpenAPI schema generation build.
# Technically only fields without a `default_factory` need to be listed here.
# See: https://github.com/pydantic/pydantic/discussions/4577
class Config:
schema_extra = {
'required': [
'id',
'graph',
'execution_graph',
'executed',
'executed_history',
'results',
'errors',
'prepared_source_mapping',
'source_prepared_mapping',
]
}
def next(self) -> BaseInvocation | None:
"""Gets the next node ready to execute."""
# TODO: enable multiple nodes to execute simultaneously by tracking currently executing nodes
# possibly with a timeout?
# If there are no prepared nodes, prepare some nodes
next_node = self._get_next_node()
if next_node is None:
prepared_id = self._prepare()
# TODO: prepare multiple nodes at once?
# while prepared_id is not None and not isinstance(self.graph.nodes[prepared_id], IterateInvocation):
# prepared_id = self._prepare()
if prepared_id is not None:
next_node = self._get_next_node()
# Get values from edges
if next_node is not None:
self._prepare_inputs(next_node)
# If next is still none, there's no next node, return None
return next_node
def complete(self, node_id: str, output: InvocationOutputsUnion):
"""Marks a node as complete"""
if node_id not in self.execution_graph.nodes:
return # TODO: log error?
# Mark node as executed
self.executed.add(node_id)
self.results[node_id] = output
# Check if source node is complete (all prepared nodes are complete)
source_node = self.prepared_source_mapping[node_id]
prepared_nodes = self.source_prepared_mapping[source_node]
if all([n in self.executed for n in prepared_nodes]):
self.executed.add(source_node)
self.executed_history.append(source_node)
def set_node_error(self, node_id: str, error: str):
"""Marks a node as errored"""
self.errors[node_id] = error
def is_complete(self) -> bool:
"""Returns true if the graph is complete"""
return self.has_error() or all((k in self.executed for k in self.graph.nodes))
def has_error(self) -> bool:
"""Returns true if the graph has any errors"""
return len(self.errors) > 0
def _create_execution_node(
self, node_path: str, iteration_node_map: list[tuple[str, str]]
) -> list[str]:
"""Prepares an iteration node and connects all edges, returning the new node id"""
node = self.graph.get_node(node_path)
self_iteration_count = -1
# If this is an iterator node, we must create a copy for each iteration
if isinstance(node, IterateInvocation):
# Get input collection edge (should error if there are no inputs)
input_collection_edge = next(
iter(self.graph._get_input_edges(node_path, "collection"))
)
input_collection_prepared_node_id = next(
n[1]
for n in iteration_node_map
if n[0] == input_collection_edge.source.node_id
)
input_collection_prepared_node_output = self.results[
input_collection_prepared_node_id
]
input_collection = getattr(
input_collection_prepared_node_output, input_collection_edge.source.field
)
self_iteration_count = len(input_collection)
new_nodes = list()
if self_iteration_count == 0:
# TODO: should this raise a warning? It might just happen if an empty collection is input, and should be valid.
return new_nodes
# Get all input edges
input_edges = self.graph._get_input_edges(node_path)
# Create new edges for this iteration
# For collect nodes, this may contain multiple inputs to the same field
new_edges = list()
for edge in input_edges:
for input_node_id in (
n[1] for n in iteration_node_map if n[0] == edge.source.node_id
):
new_edge = Edge(
source=EdgeConnection(node_id=input_node_id, field=edge.source.field),
destination=EdgeConnection(node_id="", field=edge.destination.field),
)
new_edges.append(new_edge)
# Create a new node (or one for each iteration of this iterator)
for i in range(self_iteration_count) if self_iteration_count > 0 else [-1]:
# Create a new node
new_node = copy.deepcopy(node)
# Create the node id (use a random uuid)
new_node.id = str(uuid.uuid4())
# Set the iteration index for iteration invocations
if isinstance(new_node, IterateInvocation):
new_node.index = i
# Add to execution graph
self.execution_graph.add_node(new_node)
self.prepared_source_mapping[new_node.id] = node_path
if node_path not in self.source_prepared_mapping:
self.source_prepared_mapping[node_path] = set()
self.source_prepared_mapping[node_path].add(new_node.id)
# Add new edges to execution graph
for edge in new_edges:
new_edge = Edge(
source=edge.source,
destination=EdgeConnection(node_id=new_node.id, field=edge.destination.field),
)
self.execution_graph.add_edge(new_edge)
new_nodes.append(new_node.id)
return new_nodes
def _iterator_graph(self) -> nx.DiGraph:
"""Gets a DiGraph with edges to collectors removed so an ancestor search produces all active iterators for any node"""
g = self.graph.nx_graph()
collectors = (
n
for n in self.graph.nodes
if isinstance(self.graph.nodes[n], CollectInvocation)
)
for c in collectors:
g.remove_edges_from(list(g.in_edges(c)))
return g
def _get_node_iterators(self, node_id: str) -> list[str]:
"""Gets iterators for a node"""
g = self._iterator_graph()
iterators = [
n
for n in nx.ancestors(g, node_id)
if isinstance(self.graph.nodes[n], IterateInvocation)
]
return iterators
def _prepare(self) -> Optional[str]:
# Get flattened source graph
g = self.graph.nx_graph_flat()
# Find next unprepared node where all source nodes are executed
sorted_nodes = nx.topological_sort(g)
next_node_id = next(
(
n
for n in sorted_nodes
if n not in self.source_prepared_mapping
and all((e[0] in self.executed for e in g.in_edges(n)))
),
None,
)
if next_node_id == None:
return None
# Get all parents of the next node
next_node_parents = [e[0] for e in g.in_edges(next_node_id)]
# Create execution nodes
next_node = self.graph.get_node(next_node_id)
new_node_ids = list()
if isinstance(next_node, CollectInvocation):
# Collapse all iterator input mappings and create a single execution node for the collect invocation
all_iteration_mappings = list(
itertools.chain(
*(
((s, p) for p in self.source_prepared_mapping[s])
for s in next_node_parents
)
)
)
# all_iteration_mappings = list(set(itertools.chain(*prepared_parent_mappings)))
create_results = self._create_execution_node(
next_node_id, all_iteration_mappings
)
if create_results is not None:
new_node_ids.extend(create_results)
else: # Iterators or normal nodes
# Get all iterator combinations for this node
# Will produce a list of lists of prepared iterator nodes, from which results can be iterated
iterator_nodes = self._get_node_iterators(next_node_id)
iterator_nodes_prepared = [
list(self.source_prepared_mapping[n]) for n in iterator_nodes
]
iterator_node_prepared_combinations = list(
itertools.product(*iterator_nodes_prepared)
)
# Select the correct prepared parents for each iteration
# For every iterator, the parent must either not be a child of that iterator, or must match the prepared iteration for that iterator
# TODO: Handle a node mapping to none
eg = self.execution_graph.nx_graph_flat()
prepared_parent_mappings = [[(n, self._get_iteration_node(n, g, eg, it)) for n in next_node_parents] for it in iterator_node_prepared_combinations] # type: ignore
# Create execution node for each iteration
for iteration_mappings in prepared_parent_mappings:
create_results = self._create_execution_node(next_node_id, iteration_mappings) # type: ignore
if create_results is not None:
new_node_ids.extend(create_results)
return next(iter(new_node_ids), None)
def _get_iteration_node(
self,
source_node_path: str,
graph: nx.DiGraph,
execution_graph: nx.DiGraph,
prepared_iterator_nodes: list[str],
) -> Optional[str]:
"""Gets the prepared version of the specified source node that matches every iteration specified"""
prepared_nodes = self.source_prepared_mapping[source_node_path]
if len(prepared_nodes) == 1:
return next(iter(prepared_nodes))
# Check if the requested node is an iterator
prepared_iterator = next(
(n for n in prepared_nodes if n in prepared_iterator_nodes), None
)
if prepared_iterator is not None:
return prepared_iterator
# Filter to only iterator nodes that are a parent of the specified node, in tuple format (prepared, source)
iterator_source_node_mapping = [
(n, self.prepared_source_mapping[n]) for n in prepared_iterator_nodes
]
parent_iterators = [
itn
for itn in iterator_source_node_mapping
if nx.has_path(graph, itn[1], source_node_path)
]
return next(
(
n
for n in prepared_nodes
if all(
pit
for pit in parent_iterators
if nx.has_path(execution_graph, pit[0], n)
)
),
None,
)
def _get_next_node(self) -> Optional[BaseInvocation]:
g = self.execution_graph.nx_graph()
sorted_nodes = nx.topological_sort(g)
next_node = next((n for n in sorted_nodes if n not in self.executed), None)
if next_node is None:
return None
return self.execution_graph.nodes[next_node]
def _prepare_inputs(self, node: BaseInvocation):
input_edges = [e for e in self.execution_graph.edges if e.destination.node_id == node.id]
if isinstance(node, CollectInvocation):
output_collection = [
getattr(self.results[edge.source.node_id], edge.source.field)
for edge in input_edges
if edge.destination.field == "item"
]
setattr(node, "collection", output_collection)
else:
for edge in input_edges:
output_value = getattr(self.results[edge.source.node_id], edge.source.field)
setattr(node, edge.destination.field, output_value)
# TODO: Add API for modifying underlying graph that checks if the change will be valid given the current execution state
def _is_edge_valid(self, edge: Edge) -> bool:
if not self._is_edge_valid(edge):
return False
# Invalid if destination has already been prepared or executed
if edge.destination.node_id in self.source_prepared_mapping:
return False
# Otherwise, the edge is valid
return True
def _is_node_updatable(self, node_id: str) -> bool:
# The node is updatable as long as it hasn't been prepared or executed
return node_id not in self.source_prepared_mapping
def add_node(self, node: BaseInvocation) -> None:
self.graph.add_node(node)
def update_node(self, node_path: str, new_node: BaseInvocation) -> None:
if not self._is_node_updatable(node_path):
raise NodeAlreadyExecutedError(
f"Node {node_path} has already been prepared or executed and cannot be updated"
)
self.graph.update_node(node_path, new_node)
def delete_node(self, node_path: str) -> None:
if not self._is_node_updatable(node_path):
raise NodeAlreadyExecutedError(
f"Node {node_path} has already been prepared or executed and cannot be deleted"
)
self.graph.delete_node(node_path)
def add_edge(self, edge: Edge) -> None:
if not self._is_node_updatable(edge.destination.node_id):
raise NodeAlreadyExecutedError(
f"Destination node {edge.destination.node_id} has already been prepared or executed and cannot be linked to"
)
self.graph.add_edge(edge)
def delete_edge(self, edge: Edge) -> None:
if not self._is_node_updatable(edge.destination.node_id):
raise NodeAlreadyExecutedError(
f"Destination node {edge.destination.node_id} has already been prepared or executed and cannot have a source edge deleted"
)
self.graph.delete_edge(edge)
GraphInvocation.update_forward_refs()