otp.Source.sink#

Source.sink(ep, out_pin=None, inplace=True)#

Appends ep node to this source (inplace by default). Connects out_pin of this source to ep.

Can be used to connect onetick.query objects to onetick.py.Source.

Data schema changes (added or deleted columns) will not be detected automatically after applying this function, so the user must change the schema himself by updating onetick.py.Source.schema() property.

Parameters

ep (otq.graph_components.EpBase, otq.graph_components.EpBase.PinnedEp, Tuple[otq.graph_components.EpBase, uuid.uuid4, Optional[str], Optional[str]]) – onetick.query EP object to append to source.
out_pin (Optional[str], default=None) – name of the out pin to connect to ep
inplace (bool, default=False) – if True method will modify current object, otherwise it will return modified copy of the object.

Returns

Returns None if inplace=True.

Return type

Source or None

Examples

Adding column ‘B’ directly with onetick.query EP.

>>> data = otp.Tick(A=1)
>>> data.sink(otq.AddField(field='B', value=2))
>>> otp.run(data)
        Time  A  B
0 2003-12-01  1  2

But we can’t use this column with onetick.py methods yet:

>>> data['C'] = data['B']
Traceback (most recent call last):
 ...
AttributeError: There is no 'B' column

We should manually change source’s schema:

>>> data.schema.update(B=int)
>>> data['C'] = data['B']
>>> otp.run(data)
        Time  A  B  C
0 2003-12-01  1  2  2

Use parameter inplace=False to return modified copy of the source:

>>> data = otp.Tick(A=1)
>>> new_data = data.sink(otq.AddField(field='B', value=2), inplace=False)
>>> otp.run(data)
        Time  A
0 2003-12-01  1
>>> otp.run(new_data)
        Time  A  B
0 2003-12-01  1  2