fix: Add PushSource proto and Python class

protos/feast/core/DataSource.proto

@@ -26,14 +26,14 @@ import "feast/core/DataFormat.proto";
 import "feast/types/Value.proto";
 
 // Defines a Data Source that can be used source Feature data
-// Next available id: 22
+// Next available id: 23
 message DataSource {
   // Field indexes should *not* be reused. Not sure if fields 6-10 were used previously or not,
   // but they are going to be reserved for backwards compatibility.
   reserved 6 to 10;
 
   // Type of Data Source.
-  // Next available id: 9
+  // Next available id: 10
   enum SourceType {
     INVALID = 0;
     BATCH_FILE = 1;
@@ -44,7 +44,7 @@ message DataSource {
     STREAM_KINESIS = 4;
     CUSTOM_SOURCE = 6;
     REQUEST_SOURCE = 7;
-
+    PUSH_SOURCE = 9;
   }
 
   // Unique name of data source within the project
@@ -169,6 +169,16 @@ message DataSource {
     map<string, feast.types.ValueType.Enum> schema = 2;
   }
 
+  // Defines options for DataSource that supports pushing data to it. This allows data to be pushed to
+  // the online store on-demand, such as by stream consumers.
+  message PushOptions {
+    // Mapping of feature name to type
+    map<string, feast.types.ValueType.Enum> schema = 1;
+    // Optional batch source for the push source for historical features and materialization.
+    DataSource batch_source = 2;
+  }
+
+
   // DataSource options.
   oneof options {
     FileOptions file_options = 11;
@@ -179,5 +189,6 @@ message DataSource {
     RequestDataOptions request_data_options = 18;
     CustomSourceOptions custom_options = 16;
     SnowflakeOptions snowflake_options = 19;
+    PushOptions push_options = 22;
   }
 }

sdk/python/feast/data_source.py

@@ -522,3 +522,75 @@ def to_proto(self) -> DataSourceProto:
         data_source_proto.date_partition_column = self.date_partition_column
 
         return data_source_proto
+
+
+class PushSource(DataSource):
+    """
+    PushSource that can be used to ingest features on request
+
+    Args:
+        name: Name of the push source
+        schema: Schema mapping from the input feature name to a ValueType
+    """
+
+    name: str
+    schema: Dict[str, ValueType]
+    batch_source: Optional[DataSource]
+
+    def __init__(
+        self,
+        name: str,
+        schema: Dict[str, ValueType],
+        batch_source: Optional[DataSource] = None,
+    ):
+        """Creates a PushSource object."""
+        super().__init__(name)
+        self.schema = schema
+        self.batch_source = batch_source
+
+    def validate(self, config: RepoConfig):
+        pass
+
+    def get_table_column_names_and_types(
+        self, config: RepoConfig
+    ) -> Iterable[Tuple[str, str]]:
+        pass
+
+    @staticmethod
+    def from_proto(data_source: DataSourceProto):
+        schema_pb = data_source.push_options.schema
+        schema = {}
+        for key, value in schema_pb.items():
+            schema[key] = value
+
+        batch_source = None
+        if data_source.push_options.HasField("batch_source"):
+            batch_source = DataSource.from_proto(data_source.push_options.batch_source)
+
+        return PushSource(
+            name=data_source.name, schema=schema, batch_source=batch_source
+        )
+
+    def to_proto(self) -> DataSourceProto:
+        schema_pb = {}
+        for key, value in self.schema.items():
+            schema_pb[key] = value
+        batch_source_proto = None
+        if self.batch_source:
+            batch_source_proto = self.batch_source.to_proto()
+
+        options = DataSourceProto.PushOptions(
+            schema=schema_pb, batch_source=batch_source_proto
+        )
+        data_source_proto = DataSourceProto(
+            name=self.name, type=DataSourceProto.PUSH_SOURCE, push_options=options,
+        )
+
+        return data_source_proto
+
+    def get_table_query_string(self) -> str:
+        raise NotImplementedError
+
+    @staticmethod
+    def source_datatype_to_feast_value_type() -> Callable[[str], ValueType]:
+        raise NotImplementedError

sdk/python/tests/unit/test_data_sources.py

@@ -0,0 +1,34 @@
+from feast.data_source import PushSource
+from feast.infra.offline_stores.bigquery_source import BigQuerySource
+from feast.protos.feast.types.Value_pb2 import ValueType
+
+
+def test_push_no_batch():
+    push_source = PushSource(
+        name="test", schema={"user_id": ValueType.INT64, "ltv": ValueType.INT64}
+    )
+    push_source_proto = push_source.to_proto()
+    assert push_source_proto.push_options is not None
+    assert not push_source_proto.push_options.HasField("batch_source")
+    push_source_unproto = PushSource.from_proto(push_source_proto)
+
+    assert push_source.name == push_source_unproto.name
+    assert push_source.schema == push_source_unproto.schema
+    assert push_source.batch_source == push_source_unproto.batch_source
+
+
+def test_push_with_batch():
+    push_source = PushSource(
+        name="test",
+        schema={"user_id": ValueType.INT64, "ltv": ValueType.INT64},
+        batch_source=BigQuerySource(table="test.test"),
+    )
+    push_source_proto = push_source.to_proto()
+    assert push_source_proto.push_options is not None
+    assert push_source_proto.push_options.HasField("batch_source")
+
+    push_source_unproto = PushSource.from_proto(push_source_proto)
+
+    assert push_source.name == push_source_unproto.name
+    assert push_source.schema == push_source_unproto.schema
+    assert push_source.batch_source.name == push_source_unproto.batch_source.name