def __call__(self, data: pd.DataFrame, fmt: str = "json"):
if self._provider is None:
self._provider = Provider()
content, resource_id = self._serialize(data, fmt)
if resource_id not in self._resources:
self._resources[resource_id] = self._provider.create(
content=content,
extension=fmt,
headers={"Access-Control-Allow-Origin": "*"},
)
return {"url": self._resources[resource_id].url}
def __call__(self,
data: pd.DataFrame,
fmt: str = "json",
port: Optional[int] = None) -> Dict[str, str]:
if self._provider is None:
self._provider = Provider().start(port=port)
if port is not None and port != self._provider.port:
self._provider.stop().start(port=port)
content, resource_id = self._serialize(data, fmt)
if resource_id not in self._resources:
self._resources[resource_id] = self._provider.create(
content=content,
extension=fmt,
headers={"Access-Control-Allow-Origin": "*"},
)
return {"url": self._resources[resource_id].url}
class AltairDataServer(object):
"""Backend server for Altair datasets."""
def __init__(self):
self._provider: Optional[Provider] = None
# We need to keep references to served resources, because the background
# server uses weakrefs.
self._resources = {}
def reset(self):
if self._provider is not None:
self._provider.stop()
self._resources = {}
@staticmethod
def _serialize(data: pd.DataFrame, fmt: str) -> Tuple[str, str]:
"""Serialize data to the given format."""
if fmt == "json":
content = _data_to_json_string(data)
elif fmt == "csv":
content = _data_to_csv_string(data)
else:
raise ValueError("Unrecognized format: '{0}'".format(fmt))
return content, _compute_data_hash(content)
def __call__(self, data: pd.DataFrame, fmt: str = "json"):
if self._provider is None:
self._provider = Provider()
content, resource_id = self._serialize(data, fmt)
if resource_id not in self._resources:
self._resources[resource_id] = self._provider.create(
content=content,
extension=fmt,
headers={"Access-Control-Allow-Origin": "*"},
)
return {"url": self._resources[resource_id].url}