Support for connection attributes

[dveeden]

This makes it possible to send connection attributes.

By default _client_name and _client_version will be send.

Custom attributes can be used with the connattrs dict.

Maybe set 'program_name' to sys.argv[0] by default? and maybe also set '_pid' just like libmysql?
I didn't add anything to the testsuite.
I didn't test with cext.

$ cat test.py 
#!/usr/bin/env python
import sys
import mysql.connector

conn = mysql.connector.connect(host='127.0.0.1',user='msandbox',password='msandbox',port=5707)
cur = conn.cursor()
cur.execute('SELECT * FROM performance_schema.session_connect_attrs')
for res in cur:
    print(res)
cur.close()
conn.close()

conn = mysql.connector.connect(host='127.0.0.1',user='msandbox',password='msandbox',port=5707, connattrs={'foo': 'bar', 'program_name': sys.argv[0]})
cur = conn.cursor()
cur.execute('SELECT * FROM performance_schema.session_connect_attrs')
for res in cur:
    print(res)
cur.close()
conn.close()
$ ./test.py 
(63, bytearray(b'_client_version'), bytearray(b'2.1.1a1'), 0)
(63, bytearray(b'_client_name'), bytearray(b'MySQL Connector/Python'), 1)
(64, bytearray(b'_client_version'), bytearray(b'2.1.1a1'), 0)
(64, bytearray(b'program_name'), bytearray(b'./test.py'), 1)
(64, bytearray(b'foo'), bytearray(b'bar'), 2)
(64, bytearray(b'_client_name'), bytearray(b'MySQL Connector/Python'), 3)

[dveeden]

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[mysql-oca-bot]

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Thanks

[dveeden]

I confirm the code being submitted is offered under the terms of the OCA, and that I am authorized to contribute it.

[mysql-oca-bot]

Hi, thank you for your contribution. Your code has been assigned to an internal queue. Please follow
bug http://bugs.mysql.com/bug.php?id=77003 for updates.
Thanks