pyarrow.flight.ClientMiddleware¶
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class
pyarrow.flight.ClientMiddleware¶ Bases:
pyarrow.lib._WeakrefableClient-side middleware for a call, instantiated per RPC.
Methods here should be fast and must be infallible: they should not raise exceptions or stall indefinitely.
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__init__()¶ Initialize self. See help(type(self)) for accurate signature.
Methods
__init__()Initialize self.
call_completed(self, exception)A callback when the call finishes.
received_headers(self, headers)A callback when headers are received.
sending_headers(self)A callback before headers are sent.
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call_completed(self, exception)¶ A callback when the call finishes.
The default implementation does nothing.
- Parameters
exception (ArrowException) – If the call errored, this is the equivalent exception. Will be None if the call succeeded.
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received_headers(self, headers)¶ A callback when headers are received.
The default implementation does nothing.
- Parameters
headers (dict) – A dictionary of headers from the server. Keys are strings and values are lists of strings (for text headers) or bytes (for binary headers).
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sending_headers(self)¶ A callback before headers are sent.
- Returns
headers (dict) – A dictionary of header values to add to the request, or None if no headers are to be added. The dictionary should have string keys and string or list-of-string values.
Bytes values are allowed, but the underlying transport may not support them or may restrict them. For gRPC, binary values are only allowed on headers ending in “-bin”.
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