"""

def __init__(

self,

config: Optional[OpenLineageConfig] = None,

client: Optional[FeastOpenLineageClient] = None,

):

"""

self._config = config or OpenLineageConfig.from_env()

self._client = client or FeastOpenLineageClient(self._config)

@property

def is_enabled(self) -> bool:

"""Check if the emitter is enabled."""

return self._client.is_enabled

@property

def namespace(self) -> str:

"""Get the default namespace."""

return self._config.namespace

def _get_namespace(self, project: str) -> str:

"""

# If namespace is default "feast", just use project name

if self._config.namespace == "feast":

return project

# If custom namespace is configured, use it as prefix

return f"{self._config.namespace}/{project}"

def emit_registry_lineage(

self,

registry: "BaseRegistry",

project: str,

allow_cache: bool = True,

) -> List[bool]:

"""

if not self.is_enabled:

return []

from feast.feature_view import FeatureView

from feast.on_demand_feature_view import OnDemandFeatureView

from feast.stream_feature_view import StreamFeatureView

results = []

# Get all feature views at once (includes FeatureView, StreamFeatureView, OnDemandFeatureView)

all_feature_views: list = []

try:

all_feature_views = registry.list_all_feature_views(

project=project, allow_cache=allow_cache

)

except Exception as e:

logger.error(f"Error listing all feature views: {e}")

# Emit lineage events for each feature view type

for fv in all_feature_views:

try:

if isinstance(fv, OnDemandFeatureView):

result = self.emit_on_demand_feature_view_lineage(fv, project)

elif isinstance(fv, StreamFeatureView):

result = self.emit_stream_feature_view_lineage(fv, project)

elif isinstance(fv, FeatureView):

result = self.emit_feature_view_lineage(fv, project)

else:

continue

results.append(result)

except Exception as e:

logger.error(f"Error emitting lineage for feature view {fv.name}: {e}")

# Emit events for feature services

try:

feature_services = registry.list_feature_services(

project=project, allow_cache=allow_cache

)

for fs in feature_services:

result = self.emit_feature_service_lineage(

fs, all_feature_views, project

)

results.append(result)

except Exception as e:

logger.error(f"Error emitting feature service lineage: {e}")

logger.info(

f"Emitted {sum(results)}/{len(results)} lineage events for registry"

)

return results

def emit_feature_view_lineage(

self,

feature_view: "FeatureView",

project: str,

) -> bool:

"""

if not self.is_enabled:

return False

from feast.openlineage.mappers import feature_view_to_job

try:

namespace = self._get_namespace(project)

job, inputs, outputs = feature_view_to_job(

feature_view,

namespace=namespace,

)

# Emit a RunEvent with COMPLETE state to create lineage connection

result = self._client.emit_run_event(

job_name=job.name,

run_id=str(uuid.uuid4()),

event_type=RunState.COMPLETE,

inputs=inputs,

outputs=outputs,

job_facets=job.facets,

namespace=namespace,

)

return result

except Exception as e:

logger.error(

f"Error emitting feature view lineage for {feature_view.name}: {e}"

)

return False

def emit_stream_feature_view_lineage(

self,

stream_feature_view: "StreamFeatureView",

project: str,

) -> bool:

"""

if not self.is_enabled:

return False

from feast.openlineage.mappers import feature_view_to_job

try:

namespace = self._get_namespace(project)

# StreamFeatureView inherits from FeatureView

job, inputs, outputs = feature_view_to_job(

stream_feature_view,

namespace=namespace,

)

# Emit a RunEvent with COMPLETE state to create lineage connection

return self._client.emit_run_event(

job_name=f"stream_{job.name}",

run_id=str(uuid.uuid4()),

event_type=RunState.COMPLETE,

inputs=inputs,

outputs=outputs,

job_facets=job.facets,

namespace=namespace,

)

except Exception as e:

logger.error(

f"Error emitting stream feature view lineage for {stream_feature_view.name}: {e}"

)

return False

def emit_on_demand_feature_view_lineage(

self,

odfv: "OnDemandFeatureView",

project: str,

) -> bool:

"""

if not self.is_enabled:

return False

from feast.openlineage.facets import FeastFeatureViewFacet

from feast.openlineage.mappers import feast_field_to_schema_field

try:

from openlineage.client.facet_v2 import schema_dataset

namespace = self._get_namespace(project)

# Build inputs from sources

inputs = []

for source_name, fv_proj in odfv.source_feature_view_projections.items():

inputs.append(

InputDataset(

namespace=namespace,

name=fv_proj.name,

)

)

for source_name, req_source in odfv.source_request_sources.items():

inputs.append(

InputDataset(

namespace=namespace,

name=f"request_source_{source_name}",

)

)

# Build output

output_facets = {}

if odfv.features:

output_facets["schema"] = schema_dataset.SchemaDatasetFacet(

fields=[feast_field_to_schema_field(f) for f in odfv.features]

)

outputs = [

OutputDataset(

namespace=namespace,

name=odfv.name,

facets=output_facets, # type: ignore[arg-type]

)

]

# Build job facets

job_facets = {

"feast_featureView": FeastFeatureViewFacet(

name=odfv.name,

ttl_seconds=0,

entities=[],

features=[f.name for f in odfv.features] if odfv.features else [],

online_enabled=True,

offline_enabled=True,

mode="ON_DEMAND",

description=odfv.description if odfv.description else "",

owner=odfv.owner if hasattr(odfv, "owner") and odfv.owner else "",

tags=odfv.tags if odfv.tags else {},

)

}

# Emit a RunEvent with COMPLETE state to create lineage connection

return self._client.emit_run_event(

job_name=f"on_demand_feature_view_{odfv.name}",

run_id=str(uuid.uuid4()),

event_type=RunState.COMPLETE,

inputs=inputs,

outputs=outputs,

job_facets=job_facets,

namespace=namespace,

)

except Exception as e:

logger.error(

f"Error emitting on-demand feature view lineage for {odfv.name}: {e}"

)

return False

def emit_feature_service_lineage(

self,

feature_service: "FeatureService",

feature_views: List[

Union["FeatureView", "OnDemandFeatureView", "StreamFeatureView"]

],

project: str,

) -> bool:

"""

if not self.is_enabled:

return False

from feast.openlineage.mappers import feature_service_to_job

try:

# Find the feature views referenced by this service

namespace = self._get_namespace(project)

fv_names = {proj.name for proj in feature_service.feature_view_projections}

referenced_fvs = [fv for fv in feature_views if fv.name in fv_names]

job, inputs, outputs = feature_service_to_job(

feature_service,

referenced_fvs,

namespace=namespace,

)

# Emit a RunEvent with COMPLETE state to create lineage connection

return self._client.emit_run_event(

job_name=job.name,

run_id=str(uuid.uuid4()),

event_type=RunState.COMPLETE,

inputs=inputs,

outputs=outputs,

job_facets=job.facets,

namespace=namespace,

)

except Exception as e:

logger.error(

f"Error emitting feature service lineage for {feature_service.name}: {e}"

)

return False

def emit_materialize_start(

self,

feature_views: List["FeatureView"],

start_date: Optional[datetime],

end_date: datetime,

project: str,

run_id: Optional[str] = None,

) -> Tuple[str, bool]:

"""

if not self.is_enabled or not self._config.emit_on_materialize:

return "", False

from feast.openlineage.facets import FeastMaterializationFacet

from feast.openlineage.mappers import (

data_source_to_dataset,

online_store_to_dataset,

)

run_id = run_id or str(uuid.uuid4())

try:

namespace = self._get_namespace(project)

# Build inputs (data sources) - include both batch and stream sources

inputs = []

seen_sources = set() # Track source names to avoid duplicates

for fv in feature_views:

# Add batch source

if hasattr(fv, "batch_source") and fv.batch_source:

source_name = getattr(fv.batch_source, "name", None)

if source_name and source_name not in seen_sources:

seen_sources.add(source_name)

inputs.append(

data_source_to_dataset(

fv.batch_source,

namespace=namespace,

as_input=True,

)

)

# Add stream source (e.g., PushSource)

if hasattr(fv, "stream_source") and fv.stream_source:

source_name = getattr(fv.stream_source, "name", None)

if source_name and source_name not in seen_sources:

seen_sources.add(source_name)

inputs.append(

data_source_to_dataset(

fv.stream_source,

namespace=namespace,

as_input=True,

)

)

# Add entities as inputs (use direct name for consistency with emit_apply)

if hasattr(fv, "entities") and fv.entities:

for entity_name in fv.entities:

if entity_name and entity_name != "__dummy":

if entity_name not in seen_sources:

seen_sources.add(entity_name)

inputs.append(

InputDataset(

namespace=namespace,

name=entity_name,

)

)

# Build outputs (online store entries)

outputs = [

online_store_to_dataset(

store_type="online_store",

feature_view_name=fv.name,

namespace=namespace,

)

for fv in feature_views

]

# Build run facets

run_facets = {

"feast_materialization": FeastMaterializationFacet(

feature_views=[fv.name for fv in feature_views],

start_date=start_date.isoformat() if start_date else None,

end_date=end_date.isoformat() if end_date else None,

project=project,

)

}

success = self._client.emit_run_event(

job_name=f"materialize_{project}",

run_id=run_id,

event_type=RunState.START,

inputs=inputs,

outputs=outputs,

run_facets=run_facets,

namespace=namespace,

)

return run_id, success

except Exception as e:

logger.error(f"Error emitting materialize start event: {e}")

return run_id, False

def emit_materialize_complete(

self,

run_id: str,

feature_views: List["FeatureView"],

project: str,

rows_written: Optional[int] = None,

) -> bool:

"""

if not self.is_enabled or not self._config.emit_on_materialize:

return False

from feast.openlineage.facets import FeastMaterializationFacet

from feast.openlineage.mappers import online_store_to_dataset

try:

namespace = self._get_namespace(project)

outputs = [

online_store_to_dataset(

store_type="online_store",

feature_view_name=fv.name,

namespace=namespace,

)

for fv in feature_views

]

run_facets = {

"feast_materialization": FeastMaterializationFacet(

feature_views=[fv.name for fv in feature_views],

project=project,

rows_written=rows_written,

)

}

return self._client.emit_run_event(

job_name=f"materialize_{project}",

run_id=run_id,

event_type=RunState.COMPLETE,

outputs=outputs,

run_facets=run_facets,

namespace=namespace,

)

except Exception as e:

logger.error(f"Error emitting materialize complete event: {e}")

return False

def emit_materialize_fail(

self,

run_id: str,

project: str,

error_message: Optional[str] = None,

) -> bool:

"""

if not self.is_enabled or not self._config.emit_on_materialize:

return False

try:

from openlineage.client.facet_v2 import error_message_run

namespace = self._get_namespace(project)

run_facets = {}

if error_message:

run_facets["errorMessage"] = error_message_run.ErrorMessageRunFacet(

message=error_message,

programmingLanguage="python",

)

return self._client.emit_run_event(

job_name=f"materialize_{project}",

run_id=run_id,

event_type=RunState.FAIL,

run_facets=run_facets,

namespace=namespace,

)

except Exception as e:

logger.error(f"Error emitting materialize fail event: {e}")

return False

def emit_apply(

self,

objects: List[Any],

project: str,

) -> List[bool]:

"""

if not self.is_enabled or not self._config.emit_on_apply:

return []

from feast import Entity, FeatureService

from feast.data_source import DataSource

from feast.feature_view import FeatureView

from feast.on_demand_feature_view import OnDemandFeatureView

from feast.openlineage.facets import FeastProjectFacet

from feast.openlineage.mappers import (

data_source_to_dataset,

entity_to_dataset,

feast_field_to_schema_field,

)

from feast.stream_feature_view import StreamFeatureView

try:

from openlineage.client.facet_v2 import schema_dataset

namespace = self._get_namespace(project)

results = []

# Categorize objects

data_sources: List[DataSource] = []

entities: List[Entity] = []

feature_views: List[Union[FeatureView, OnDemandFeatureView]] = []

on_demand_feature_views: List[OnDemandFeatureView] = []

feature_services: List[FeatureService] = []

for obj in objects:

if isinstance(obj, StreamFeatureView):

feature_views.append(obj)

elif isinstance(obj, OnDemandFeatureView):

on_demand_feature_views.append(obj)

elif isinstance(obj, FeatureView):

feature_views.append(obj)

elif isinstance(obj, FeatureService):

feature_services.append(obj)

elif isinstance(obj, DataSource):

data_sources.append(obj)

elif isinstance(obj, Entity):

if obj.name != "__dummy":

entities.append(obj)

# ============================================================

# Job 1: DataSources + Entities → FeatureViews

# This matches: DataSource → FeatureView and Entity → FeatureView

# ============================================================

if feature_views or on_demand_feature_views:

fv_inputs = []

seen_inputs: set = set()

# Add explicit data sources

for ds in data_sources:

if ds.name and ds.name not in seen_inputs:

seen_inputs.add(ds.name)

fv_inputs.append(

data_source_to_dataset(

ds, namespace=namespace, as_input=True

)

)

# Add entities (using direct name to match Feast UI)

for entity in entities:

if entity.name not in seen_inputs:

seen_inputs.add(entity.name)

fv_inputs.append(entity_to_dataset(entity, namespace=namespace))

# Also add data sources from feature views

for fv in feature_views:

if hasattr(fv, "batch_source") and fv.batch_source:

source_name = getattr(fv.batch_source, "name", None)

if source_name and source_name not in seen_inputs:

seen_inputs.add(source_name)

fv_inputs.append(

data_source_to_dataset(

fv.batch_source, namespace=namespace, as_input=True

)

)

if hasattr(fv, "stream_source") and fv.stream_source:

source_name = getattr(fv.stream_source, "name", None)

if source_name and source_name not in seen_inputs:

seen_inputs.add(source_name)

fv_inputs.append(

data_source_to_dataset(

fv.stream_source, namespace=namespace, as_input=True

)

)

# Build FeatureView outputs

from openlineage.client.facet_v2 import documentation_dataset

from feast.openlineage.facets import FeastFeatureViewFacet

fv_outputs = []

for fv in feature_views:

output_facets: Dict[str, Any] = {}

# Add schema with features (includes tags in description)

if fv.features:

output_facets["schema"] = schema_dataset.SchemaDatasetFacet(

fields=[feast_field_to_schema_field(f) for f in fv.features]

)

# Add documentation facet with description

if hasattr(fv, "description") and fv.description:

output_facets["documentation"] = (

documentation_dataset.DocumentationDatasetFacet(

description=fv.description

)

)

# Add Feast-specific facet with full metadata

ttl_seconds = 0

if hasattr(fv, "ttl") and fv.ttl:

ttl_seconds = int(fv.ttl.total_seconds())

output_facets["feast_featureView"] = FeastFeatureViewFacet(

name=fv.name,

ttl_seconds=ttl_seconds,

entities=list(fv.entities)

if hasattr(fv, "entities") and fv.entities

else [],

features=[f.name for f in fv.features] if fv.features else [],

online_enabled=fv.online if hasattr(fv, "online") else True,

description=fv.description

if hasattr(fv, "description")

else "",

owner=fv.owner if hasattr(fv, "owner") else "",

tags=fv.tags if hasattr(fv, "tags") else {},

)

fv_outputs.append(

OutputDataset(

namespace=namespace,

name=fv.name,

facets=output_facets,

)

)

for odfv in on_demand_feature_views:

output_facets = {}

# Add schema with features (includes tags in description)

if odfv.features:

output_facets["schema"] = schema_dataset.SchemaDatasetFacet(

fields=[

feast_field_to_schema_field(f) for f in odfv.features

]

)

# Add documentation facet with description

if hasattr(odfv, "description") and odfv.description:

output_facets["documentation"] = (

documentation_dataset.DocumentationDatasetFacet(

description=odfv.description

)

)

# Add Feast-specific facet with full metadata

output_facets["feast_featureView"] = FeastFeatureViewFacet(

name=odfv.name,

ttl_seconds=0,

entities=list(odfv.entities)

if hasattr(odfv, "entities") and odfv.entities

else [],

features=[f.name for f in odfv.features]

if odfv.features

else [],

online_enabled=True,

description=odfv.description

if hasattr(odfv, "description")

else "",

owner=odfv.owner if hasattr(odfv, "owner") else "",

tags=odfv.tags if hasattr(odfv, "tags") else {},

)

fv_outputs.append(

OutputDataset(

namespace=namespace,

name=odfv.name,

facets=output_facets,

)

)

# Emit Job 1: Feature Views job

job_facets = {

"feast_project": FeastProjectFacet(

project_name=project,

)

}

result1 = self._client.emit_run_event(

job_name=f"feast_feature_views_{project}",

run_id=str(uuid.uuid4()),

event_type=RunState.COMPLETE,

inputs=fv_inputs,

outputs=fv_outputs,

job_facets=job_facets,

namespace=namespace,

)

results.append(result1)

if result1:

logger.info(

f"✓ Emitted feature views lineage for '{project}' "

f"({len(fv_inputs)} inputs → {len(fv_outputs)} outputs)"

)

# ============================================================

# Jobs for FeatureServices: One job per FeatureService

# Each job shows: FeatureViews (that are part of this FS) → FeatureService

# This matches Feast UI where links are only shown for actual membership

# ============================================================

for fs in feature_services:

fs_inputs = []

all_fs_features = [] # Collect all features for schema

fv_names_in_fs = [] # Track feature view names

# Only include FeatureViews that are actually part of this FeatureService

for proj in fs.feature_view_projections:

fv_name = proj.name

if fv_name:

fv_names_in_fs.append(fv_name)

# Find the feature view to get schema

input_facets: Dict[str, Any] = {}

# Use projection features if specified, otherwise use all from FV

proj_features = proj.features if proj.features else []

for fv in feature_views + on_demand_feature_views:

if fv.name == fv_name:

# Use projection features if available, else all FV features

features_to_use = (

proj_features

if proj_features

else (fv.features if fv.features else [])

)

if features_to_use:

input_facets["schema"] = (

schema_dataset.SchemaDatasetFacet(

fields=[

feast_field_to_schema_field(f)

for f in features_to_use

]

)

)

# Collect features for FS output schema

all_fs_features.extend(features_to_use)

break

fs_inputs.append(

InputDataset(

namespace=namespace,

name=fv_name,

facets=input_facets,

)

)

# Build FeatureService output with schema and metadata

fs_output_facets: Dict[str, Any] = {}

# Add schema with all features from constituent feature views

if all_fs_features:

fs_output_facets["schema"] = schema_dataset.SchemaDatasetFacet(

fields=[feast_field_to_schema_field(f) for f in all_fs_features]

)

# Add documentation with feature view list

if fv_names_in_fs:

from openlineage.client.facet_v2 import documentation_dataset

fs_output_facets["documentation"] = (

documentation_dataset.DocumentationDatasetFacet(

description=(

f"Feature Service '{fs.name}' aggregates features from: "

f"{', '.join(fv_names_in_fs)}. "

f"Total features: {len(all_fs_features)}."

)

)

)

# Add Feast-specific facet with detailed metadata

from feast.openlineage.facets import FeastFeatureServiceFacet

fs_output_facets["feast_featureService"] = FeastFeatureServiceFacet(

name=fs.name,

feature_views=fv_names_in_fs,

feature_count=len(all_fs_features),

description=fs.description if fs.description else "",

owner=fs.owner if fs.owner else "",

tags=fs.tags if fs.tags else {},

logging_enabled=getattr(fs, "logging", None) is not None,

)

fs_output = OutputDataset(

namespace=namespace,

name=fs.name,

facets=fs_output_facets,

)

# Emit a job for this specific FeatureService

job_facets = {

"feast_project": FeastProjectFacet(

project_name=project,

)

}

result = self._client.emit_run_event(

job_name=f"feature_service_{fs.name}", # Prefix to avoid conflict with dataset

run_id=str(uuid.uuid4()),

event_type=RunState.COMPLETE,

inputs=fs_inputs,

outputs=[fs_output],

job_facets=job_facets,

namespace=namespace,

)

results.append(result)

return results

except Exception as e:

logger.error(f"Error emitting project lineage for {project}: {e}")

return [False]

def close(self):

"""Close the underlying client."""