supervisor4/python3

From @nunojpg in issue coderanger#17:

> Under latest versions I found 3 issues:
> - if processes output non-ASCII output then the event RESULT message
>   sends the wrong length.
> - event_handler response is byte and not string, so all the code
>   fails.
> - empty lines are printed to log

coderanger#17

supervisor_stdout.py

@@ -18,11 +18,11 @@ def main():
         write_stdout('RESULT %s\n%s'%(len(data.encode("utf-8")), data)) # transition from READY to ACKNOWLEDGED
 
 def event_handler(event, response):
-    line, data = response.split('\n', 1)
-    headers = dict([ x.split(':') for x in line.split() ])
-    lines = data.split('\n')
-    prefix = '%s %s | '%(headers['processname'], headers['channel'])
-    print('\n'.join([ prefix + l for l in lines ]))
+    line, data = response.split(b'\n', 1)
+    headers = dict([ x.split(b':') for x in line.split() ])
+    lines = data.split(b'\n')
+    prefix = b'%s %s | '%(headers[b'processname'], headers[b'channel'])
+    print(b'\n'.join([ prefix + l for l in lines if l]).decode('utf-8'))
 
 if __name__ == '__main__':
     main()