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https://issues.apache.org/jira/browse/ARROW-15645?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17497452#comment-17497452
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Antoine Pitrou commented on ARROW-15645:
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Ok, so my guess is that both server (Java) and client (Python/C++) are on
s390x, right?
On Arrow C++ 3.0.0, no conversion happens in either Java or C++, and it works
since client and server have the same endianness (both big endian).
On Arrow C++ 4.0.0+, the Flight client reads the endianness information from
the IPC stream. If the machine endianness doesn't match the stream endianness,
endianness conversion is attempted by default.
Here is the problem: Arrow Java (and the Java Flight server) seems to always
set the endianness information to "little" (even on a big endian machine).
Arrow C++ interprets that information as meaning a conversion is needed, while
the data is already in the right format.
> Data read through Flight is having endianness issue on s390x
> ------------------------------------------------------------
>
> Key: ARROW-15645
> URL: https://issues.apache.org/jira/browse/ARROW-15645
> Project: Apache Arrow
> Issue Type: Bug
> Components: C++, FlightRPC, Python
> Affects Versions: 5.0.0
> Environment: Linux s390x (big endian)
> Reporter: Ravi Gummadi
> Priority: Major
>
> Am facing an endianness issue on s390x(big endian) when converting the data
> read through flight to pandas data frame.
> (1) table.validate() fails with error
> {code}
> Traceback (most recent call last):
> File "/tmp/2.py", line 51, in <module>
> table.validate()
> File "pyarrow/table.pxi", line 1232, in pyarrow.lib.Table.validate
> File "pyarrow/error.pxi", line 99, in pyarrow.lib.check_status
> pyarrow.lib.ArrowInvalid: Column 1: In chunk 0: Invalid: Negative offsets in
> binary array
> {code}
> (2) table.to_pandas() gives a segmentation fault
> ____________
> Here is a sample code that I am using:
> {code:python}
> from pyarrow import flight
> import os
> import json
> flight_endpoint = os.environ.get("flight_server_url",
> "grpc+tls://...local:443")
> print(flight_endpoint)
> #
> class TokenClientAuthHandler(flight.ClientAuthHandler):
> """An example implementation of authentication via handshake.
> With the default constructor, the user token is read from the
> environment: TokenClientAuthHandler().
> You can also pass a user token as parameter to the constructor,
> TokenClientAuthHandler(yourtoken).
> """
> def \_\_init\_\_(self, token: str = None):
> super().\_\_init\__()
> if( token != None):
> strToken = strToken = 'Bearer {}'.format(token)
> else:
> strToken = 'Bearer {}'.format(os.environ.get("some_auth_token"))
> self.token = strToken.encode('utf-8')
> #print(self.token)
> def authenticate(self, outgoing, incoming):
> outgoing.write(self.token)
> self.token = incoming.read()
> def get_token(self):
> return self.token
>
> readClient = flight.FlightClient(flight_endpoint)
> readClient.authenticate(TokenClientAuthHandler())
> cmd = json.dumps(\{...})
> descriptor = flight.FlightDescriptor.for_command(cmd)
> flightInfo = readClient.get_flight_info(descriptor)
> reader = readClient.do_get(flightInfo.endpoints[0].ticket)
> table = reader.read_all()
> print(table)
> print(table.num_columns)
> print(table.num_rows)
> table.validate()
> table.to_pandas()
> {code}
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