Fix promise output when falling back to SR python

On python3 slapos.core for python2 software release, the output was bytes:

```
2021-11-05 17:28:39 slapos[12654] INFO Error with promises for the following partitions:
2021-11-05 17:28:39 slapos[12654] INFO   slappart7[balancer]: b'Promise \'check-apachedex-result.py\' failed with output: ERROR \'"/srv/slapgrid/slappart3/srv/runner/software/cc0326f0dcb093f56c01291c300c8481/bin/check-apachedex-result" --apachedex_path "/srv/slapgrid/slappart3/srv/runner/instance/slappart7/srv/monitor/private/apachedex" --status_file /srv/slapgrid/slappart3/srv/runner/instance/slappart7/srv/monitor/private/apachedex.report.json --threshold "70"\' run with failure, output: \'Score too low: 0% - Threshold: 70.0%\\n\''
```

See merge request nexedi/slapos.core!344

slapos/cli/coloredlogs/__init__.py

@@ -176,7 +176,10 @@ class ColoredStreamHandler(logging.StreamHandler):
         message = record.msg
         try:
             if not isinstance(message, basestring):
-                message = unicode(message)
+                try:
+                    message = unicode(message)
+                except UnicodeDecodeError:
+                    message = unicode(str(message), 'utf-8', 'replace')
         except NameError:
             if not isinstance(message, str):
                 message = str(message)

slapos/grid/promise/runpromises.py

@@ -64,5 +64,9 @@ os.dup2(2, 1)
 try:
   promise_checker.run()
 except Exception as e:
-  os.write(out, str(e))
+  if sys.version_info < (3,):
+    error_str = unicode(str(e), 'utf-8', 'repr')
+  else:
+    error_str = str(e)
+  os.write(out, error_str.encode('utf-8', 'repr'))
   sys.exit(2 if isinstance(e, PromiseError) else 1)

slapos/grid/slapgrid.py

@@ -730,6 +730,7 @@ stderr_logfile_backups=1
         command,
         preexec_fn=lambda: dropPrivileges(uid, gid, logger=self.logger),
         cwd=instance_path,
+        universal_newlines=True,
         stdout=subprocess.PIPE)
       promises = plugins + len(listifdir(legacy_promise_dir))
       # Add a timeout margin to let the process kill the promises and cleanup

slapos/tests/test_slapgrid.py

 ##############################################################################
-#
+# coding: utf-8
 # Copyright (c) 2010 Vifib SARL and Contributors. All Rights Reserved.
 #
 # WARNING: This program as such is intended to be used by professional
@@ -69,7 +69,7 @@ from slapos.util import dumps
 from slapos import __path__ as slapos_path
 from zope import __path__ as zope_path
 
-PROMISE_PATHS = sorted(set(map(os.path.dirname, slapos_path + zope_path)))
+PROMISE_PATHS = sorted(set(map(os.path.dirname, list(slapos_path) + list(zope_path))))
 
 import httmock
 
@@ -119,6 +119,7 @@ touch worked
 """
 
 PROMISE_CONTENT_TEMPLATE = """
+# coding: utf-8
 import sys
 sys.path[0:0] = %(paths)r
 
@@ -1757,41 +1758,51 @@ echo %s; echo %s; exit 42""" % (line1, line2))
   def test_processing_summary(self):
     """At the end of instance processing, a summary of partition with errors is displayed.
     """
-    computer = ComputerForTest(self.software_root, self.instance_root, 3, 3)
-    _, instance1, instance2 = computer.instance_list
+    computer = ComputerForTest(self.software_root, self.instance_root, 4, 4)
+    _, instance1, instance2, instance3 = computer.instance_list
     # instance0 has no problem, it is not in summary
 
     # instance 1 fails software
-    instance1 = computer.instance_list[1]
     instance1.software = computer.software_list[1]
     instance1.software.setBuildout("""#!/bin/sh
         echo fake buildout error
         exit 1""")
 
-    # instance 2 fails promises
-    instance2 = computer.instance_list[2]
+    # instance 2 fails old style promises
     instance2.requested_state = 'started'
     instance2.setPromise("failing_promise", """#!/bin/sh
-        echo fake promise error
+        echo héhé fake promise error
         exit 1""")
 
+    # instance 3 fails promise plugin
+    instance3.requested_state = 'started'
+    instance3.setPluginPromise(
+        "failing_promise_plugin.py",
+        promise_content="""if 1:
+          return self.logger.error("héhé fake promise plugin error")
+        """,
+    )
+
     with httmock.HTTMock(computer.request_handler), \
         patch.object(self.grid.logger, 'info',) as dummyLogger:
       self.launchSlapgrid()
 
     # reconstruct the string like logger does
     self.assertEqual(
-        dummyLogger.mock_calls[-4][1][0] % dummyLogger.mock_calls[-4][1][1:],
+        dummyLogger.mock_calls[-5][1][0] % dummyLogger.mock_calls[-5][1][1:],
         'Error while processing the following partitions:')
     self.assertRegexpMatches(
-        dummyLogger.mock_calls[-3][1][0] % dummyLogger.mock_calls[-3][1][1:],
+        dummyLogger.mock_calls[-4][1][0] % dummyLogger.mock_calls[-4][1][1:],
         r"  1\[\(not ready\)\]: Failed to run buildout profile in directory '.*/instance/1':\nfake buildout error\n\n")
     self.assertEqual(
-        dummyLogger.mock_calls[-2][1][0] % dummyLogger.mock_calls[-2][1][1:],
+        dummyLogger.mock_calls[-3][1][0] % dummyLogger.mock_calls[-3][1][1:],
         'Error with promises for the following partitions:')
+    self.assertEqual(
+        dummyLogger.mock_calls[-2][1][0] % dummyLogger.mock_calls[-2][1][1:],
+        "  2[(not ready)]: Promise 'failing_promise' failed with output: héhé fake promise error")
     self.assertEqual(
         dummyLogger.mock_calls[-1][1][0] % dummyLogger.mock_calls[-1][1][1:],
-        "  2[(not ready)]: Promise 'failing_promise' failed with output: fake promise error")
+        "  3[(not ready)]: Promise 'failing_promise_plugin.py' failed with output: héhé fake promise plugin error")
 
   def test_partition_force_stop(self):
     """
@@ -4162,6 +4173,26 @@ class TestSlapgridPluginPromiseWithInstancePython(TestSlapgridPromiseWithMaster)
       super(TestSlapgridPluginPromiseWithInstancePython, self).tearDown()
     self.assertEqual(self.expect_plugin, called)
 
+  def test_failed_promise_output(self):
+    computer = ComputerForTest(self.software_root, self.instance_root, 1, 1)
+    instance, = computer.instance_list
+
+    instance.requested_state = 'started'
+    instance.setPluginPromise(
+        "failing_promise_plugin.py",
+        promise_content="""if 1:
+          return self.logger.error("héhé fake promise plugin error")
+        """,
+    )
+
+    with httmock.HTTMock(computer.request_handler), \
+        patch.object(self.grid.logger, 'info',) as dummyLogger:
+      self.launchSlapgrid()
+
+    self.assertEqual(
+        dummyLogger.mock_calls[-1][1][0] % dummyLogger.mock_calls[-1][1][1:],
+        "  0[(not ready)]: Promise 'failing_promise_plugin.py' failed with output: héhé fake promise plugin error")
+
 
 class TestSVCBackend(unittest.TestCase):
   """Tests for supervisor backend.