[LNT] Python 3 support: fix printing of exceptions

[thopre]

Summary

A number of SQLAlchemy exception are printed by using their message
attribute. However PEP-352 deprecates this attribute from Python 2.6
onwards and drop it for Python 3 and later versions.

This commit replaces printing the message attribute by printing the
exception itself, relying on the str method. This is actually
equivalent for exceptions with only a single argument (as required for
all exceptions on Python 3) as can be seen by the message property
getter in the aforementioned PEP.

[PrzemekWirkus]

LGTM

[thopre]

Committed as c57e3b02d4344ada87ecd63139a58a15b2b3dbaa

lnt/server/db/migrations/upgrade_15_to_16.py

 
 def _mk_index_on(engine, ts_name):
     fc_table = introspect_table(engine, "{}_FieldChangeV2".format(ts_name))
 
     fast_fc_lookup = Index('idx_fast_fieldchange_lookup', fc_table.c.StartOrderID)
     try:
         fast_fc_lookup.create(engine)
     except (sqlalchemy.exc.OperationalError, sqlalchemy.exc.ProgrammingError) as e:
-        logger.warning("Skipping index creation on {}, because of {}".format(fc_table.name, e.message))
+        logger.warning("Skipping index creation on {}, because of {}".format(fc_table.name, e))
 
 
 def upgrade(engine):
     """Add an index to FieldChangeV2 for each fo the test-suites.
     """
 
     test_suite = introspect_table(engine, 'TestSuite')
 
     with engine.begin() as trans:
         db_keys = list(trans.execute(select([test_suite])))
 
     for suite in db_keys:
         with engine.begin() as trans:
             _mk_index_on(trans, suite[2])

lnt/server/db/migrations/upgrade_16_to_17.py

 
 def _mk_index_on(engine, ts_name):
     fc_table = introspect_table(engine, "{}_RegressionIndicator".format(ts_name))
 
     fast_fc_lookup = Index('idx_fast_ri_lookup', fc_table.c.RegressionID)
     try:
         fast_fc_lookup.create(engine)
     except (sqlalchemy.exc.OperationalError, sqlalchemy.exc.ProgrammingError) as e:
-        logger.warning("Skipping index creation on {}, because of {}".format(fc_table.name, e.message))
+        logger.warning("Skipping index creation on {}, because of {}".format(fc_table.name, e))
 
 
 def upgrade(engine):
     """Add an index to FieldChangeV2 for each fo the test-suites.
     """
 
     test_suite = introspect_table(engine, 'TestSuite')
 
     with engine.begin() as trans:
         db_keys = list(trans.execute(select([test_suite])))
 
     for suite in db_keys:
         with engine.begin() as trans:
             _mk_index_on(trans, suite[2])

lnt/tests/test_suite.py

def _lit(self, path, test, profile):
         except subprocess.CalledProcessError:
             # LIT is expected to exit with code 1 if there were test
             # failures!
             pass
         try:
             return json.loads(open(output_json_path.name).read())
         except ValueError as e:
             fatal("Running test-suite did not create valid json report "
-                  "in {}: {}".format(output_json_path.name, e.message))
+                  "in {}: {}".format(output_json_path.name, e))
 
     def _is_pass_code(self, code):
         return code in ('PASS', 'XPASS', 'XFAIL')
 
     def _get_lnt_code(self, code):
         return {
             'FAIL': lnt.testing.FAIL,
             'NOEXE': lnt.testing.FAIL,

lnt/util/ImportData.py

try:
 
         run = ts.importDataFromDict(session, data, config=db_config,
                                     select_machine=select_machine,
                                     merge_run=merge_run)
     except KeyboardInterrupt:
         raise
     except Exception as e:
         import traceback
-        result['error'] = "import failure: %s" % e.message
+        result['error'] = "import failure: %s" % e
         result['message'] = traceback.format_exc()
         if isinstance(e, lnt.server.db.testsuitedb.MachineInfoChanged):
             result['message'] += \
                 '\n\nNote: Use --select-machine=update to update ' \
                 'the existing machine information.\n'
         return result
 
     # If the import succeeded, save the import path.