gitbase returns commit_author_when that can't be parsed by pymysql

[smacker]

Reproduce:

git clone gitlab.com/gitlab-org/gitlab-test
<run gitbase with this repo>

query:

select commit_author_when from commits where repository_id = 'gitlab-test';

returns

...
292278994-08-17 07:12:55
...

If you try to query it with pymysql it would return error:

ValueError: invalid literal for int() with base 10: '4-'

full traceback:

---------------------------------------------------------------------------
ValueError                                Traceback (most recent call last)
<ipython-input-8-80cb0324a498> in <module>
      8 #     i += 1
      9 
---> 10 query_gitbase("select commit_author_when from commits")

/home/jovyan/work/gitbase.py in query_gitbase(sql_query, host, port, user, password, db)
     50             # might be broken.
     51             _kill_conn(id, host, port, user, password, db)
---> 52         raise e
     53     finally:
     54         connection.close()

/home/jovyan/work/gitbase.py in query_gitbase(sql_query, host, port, user, password, db)
     43 
     44         with connection.cursor() as cursor:
---> 45             cursor.execute(sql_query)
     46             return cursor.fetchall()
     47     except (Exception, KeyboardInterrupt) as e:

/usr/local/lib/python3.6/dist-packages/pymysql/cursors.py in execute(self, query, args)
    168         query = self.mogrify(query, args)
    169 
--> 170         result = self._query(query)
    171         self._executed = query
    172         return result

/usr/local/lib/python3.6/dist-packages/pymysql/cursors.py in _query(self, q)
    326         self._last_executed = q
    327         self._clear_result()
--> 328         conn.query(q)
    329         self._do_get_result()
    330         return self.rowcount

/usr/local/lib/python3.6/dist-packages/pymysql/connections.py in query(self, sql, unbuffered)
    515                 sql = sql.encode(self.encoding, 'surrogateescape')
    516         self._execute_command(COMMAND.COM_QUERY, sql)
--> 517         self._affected_rows = self._read_query_result(unbuffered=unbuffered)
    518         return self._affected_rows
    519 

/usr/local/lib/python3.6/dist-packages/pymysql/connections.py in _read_query_result(self, unbuffered)
    730         else:
    731             result = MySQLResult(self)
--> 732             result.read()
    733         self._result = result
    734         if result.server_status is not None:

/usr/local/lib/python3.6/dist-packages/pymysql/connections.py in read(self)
   1080                 self._read_load_local_packet(first_packet)
   1081             else:
-> 1082                 self._read_result_packet(first_packet)
   1083         finally:
   1084             self.connection = None

/usr/local/lib/python3.6/dist-packages/pymysql/connections.py in _read_result_packet(self, first_packet)
   1150         self.field_count = first_packet.read_length_encoded_integer()
   1151         self._get_descriptions()
-> 1152         self._read_rowdata_packet()
   1153 
   1154     def _read_rowdata_packet_unbuffered(self):

/usr/local/lib/python3.6/dist-packages/pymysql/connections.py in _read_rowdata_packet(self)
   1188                 self.connection = None  # release reference to kill cyclic reference.
   1189                 break
-> 1190             rows.append(self._read_row_from_packet(packet))
   1191 
   1192         self.affected_rows = len(rows)

/usr/local/lib/python3.6/dist-packages/pymysql/connections.py in _read_row_from_packet(self, packet)
   1207                 if DEBUG: print("DEBUG: DATA = ", data)
   1208                 if converter is not None:
-> 1209                     data = converter(data)
   1210             row.append(data)
   1211         return tuple(row)

/usr/local/lib/python3.6/dist-packages/pymysql/converters.py in convert_mysql_timestamp(timestamp)
    330     year, month, day, hour, minute, second = \
    331         int(timestamp[:4]), int(timestamp[4:6]), int(timestamp[6:8]), \
--> 332         int(timestamp[8:10]), int(timestamp[10:12]), int(timestamp[12:14])
    333     try:
    334         return datetime.datetime(year, month, day, hour, minute, second)

most probably some other drivers would also fail to parse such datetime.

[mcuadros]

The DATETIME type is used for values that contain both date and time parts. MySQL retrieves and displays DATETIME values in 'YYYY-MM-DD HH:MM:SS' format. The supported range is '1000-01-01 00:00:00' to '9999-12-31 23:59:59'.

So we should limit the range of dates from '1000-01-01 00:00:00' to '9999-12-31 23:59:59'

[erizocosmico]

Needs src-d/go-mysql-server#694 merged and updated before applying the fix here. Will leave blocked until then.