[Python] TypeError: A Message class can only inherit from Message

[Nukesor]

Hi!

I'm currently trying to run several Flask server instances with tensorflow inside of them.
The server instances are managed by an uWSGI emperor.
As long as I start the instance without the emperor, everything works perfectly fine:

uwsgi -s /tmp/solar.sock --manage-script-name --mount /=server:app --chown www-data --plugins python35 --venv ./venv

But as soon as i try to launch it utilizing the emperor, I get this error during app initialization:

Traceback (most recent call last):
  File "./server/__init__.py", line 6, in <module>
    from server.predict_service import PredictService
  File "./server/predict_service.py", line 1, in <module>
    import tensorflow as tf
  File "/opt/apps/solar/venv/lib/python3.5/site-packages/tensorflow/__init__.py", line 24, in <module>
    from tensorflow.python import *
  File "/opt/apps/solar/venv/lib/python3.5/site-packages/tensorflow/python/__init__.py", line 52, in <module>
    from tensorflow.core.framework.graph_pb2 import *
  File "/opt/apps/solar/venv/lib/python3.5/site-packages/tensorflow/core/framework/graph_pb2.py", line 10, in <module>
    from google.protobuf import descriptor_pb2
  File "/opt/apps/solar/venv/lib/python3.5/site-packages/google/protobuf/descriptor_pb2.py", line 1716, in <module>
    __module__ = 'google.protobuf.descriptor_pb2'
TypeError: A Message class can only inherit from Message

I really don't know what causes this to happen. I know that this is a rare setup, but I would really appreciate every help I could get on this topic.

[Cristian-Malinescu]

I'm not so sure it is protobuf problem. It happens to me in the Spyder's iPython console also when trying to run the code for more than once, the 1st run executes with no errors.

`...
tensorflow.python.platform.sysconfig, tensorflow.python.platform.test, tensorflow.python.client.device_lib, tensorflow.core.framework.device_attributes_pb2, tensorflow.python.framework.test_util, tensorflow.python.platform.googletest, tensorflow.python.platform.benchmark, tensorflow.core.util.test_log_pb2, tensorflow.python.client.timeline, tensorflow.python.util.protobuf, tensorflow.python.util.protobuf.compare, tensorflow.python.ops.gradient_checker, unittest.mock, tensorflow.python.util.lazy_loader
Traceback (most recent call last):

File "", line 1, in
runfile('/opt/[...]/main.py', wdir='/opt/[...]')

File "/opt/[...]/lib/python3.6/site-packages/spyder/utils/site/sitecustomize.py", line 688, in runfile
execfile(filename, namespace)

File "/opt/[...]/lib/python3.6/site-packages/spyder/utils/site/sitecustomize.py", line 101, in execfile
exec(compile(f.read(), filename, 'exec'), namespace)

File "/opt/[...]/main.py", line 5, in
import tensorflow as tf

File "/opt/[...]/lib64/python3.6/site-packages/tensorflow/init.py", line 24, in
from tensorflow.python import *

File "/opt/[...]/lib64/python3.6/site-packages/tensorflow/python/init.py", line 52, in
from tensorflow.core.framework.graph_pb2 import *

File "/opt/[...]/lib64/python3.6/site-packages/tensorflow/core/framework/graph_pb2.py", line 10, in
from google.protobuf import descriptor_pb2

File "/opt/[...]/lib64/python3.6/site-packages/google/protobuf/descriptor_pb2.py", line 1771, in
module = 'google.protobuf.descriptor_pb2'

TypeError: A Message class can only inherit from Message`

Same code works perfect when launched from command line python. I suspect the issue is due to some code cashing done either by Spyder/iPython or emperor.

[yananzhaotpg]

I have the same problem.

[Venkat-Rajgopal]

Same issue with me. 1st run in Spyder executes and later it crashes. I have to restart the kernel every time. Works fine from the command line. Any fix to this ?

[alanleemachinelearning]

I got the same problem, any way can solve it ?

[pbrumblay]

I received this error with the protobuf library when running within a python:3 container which appears to be using debian jessie (see: https://hub.docker.com/_/python/). I did not get the error after switching to python:3-alpine.

[majinyu666]

Update on 2017-10-15
I was working with default python3 on ubuntu. Now I got a virtualenv to work in, installed all the packages required without all the packages not required. Now it works just fine.

---

Original comment
My code is import tensorflow as tf , yes, just one line. Only the first time will be OK, the next time running this will raise TypeError, unless i restart console.

Traceback (most recent call last):

File "", line 1, in
runfile('/home/miles/Python/tensorflow/examples/tensorflow_core_tutorial.py', wdir='/home/miles/Python/tensorflow/examples')

File "/home/miles/.local/lib/python3.5/site-packages/spyder/utils/site/sitecustomize.py", line 710, in runfile
execfile(filename, namespace)

File "/home/miles/.local/lib/python3.5/site-packages/spyder/utils/site/sitecustomize.py", line 101, in execfile
exec(compile(f.read(), filename, 'exec'), namespace)

File "/home/miles/Python/tensorflow/examples/tensorflow_core_tutorial.py", line 2, in
import tensorflow as tf

File "/home/miles/.local/lib/python3.5/site-packages/tensorflow/init.py", line 24, in
from tensorflow.python import *

File "/home/miles/.local/lib/python3.5/site-packages/tensorflow/python/init.py", line 52, in
from tensorflow.core.framework.graph_pb2 import *

File "/home/miles/.local/lib/python3.5/site-packages/tensorflow/core/framework/graph_pb2.py", line 10, in
from google.protobuf import descriptor_pb2

File "/home/miles/.local/lib/python3.5/site-packages/google/protobuf/descriptor_pb2.py", line 1771, in
module = 'google.protobuf.descriptor_pb2'

TypeError: A Message class can only inherit from Message

But directly import tensorflow in the console will always be OK, like this:
in [1]: import tensorflow as tf
in [2]: import tensorflow as tf
in [3]: import tensorflow as tf
in [4]: import tensorflow as tf
...
So strange..
Using Spyder 3.2.3, Python 3.5.2, iPython 6.2.1, on Ubuntu-16.04-TLS

[bkanuka]

I'm having the same error, but on Python 2.7 on Ubuntu 16.04. Nothing to do with Spyder or tf, but it happens only at import like everyone else:

File "/usr/local/lib/python2.7/dist-packages/gmusicapi/__init__.py", line 4, in <module>
  from gmusicapi.clients import Webclient, Musicmanager, Mobileclient
File "/usr/local/lib/python2.7/dist-packages/gmusicapi/clients/__init__.py", line 5, in <module>
  from gmusicapi.clients.musicmanager import Musicmanager, OAUTH_FILEPATH
File "/usr/local/lib/python2.7/dist-packages/gmusicapi/clients/musicmanager.py", line 27, in <module>
  from gmusicapi.protocol import musicmanager, upload_pb2, locker_pb2
File "/usr/local/lib/python2.7/dist-packages/gmusicapi/protocol/musicmanager.py", line 24, in <module>
  from gmusicapi.protocol import upload_pb2, locker_pb2, download_pb2
File "/usr/local/lib/python2.7/dist-packages/gmusicapi/protocol/upload_pb2.py", line 10, in <module>
  from google.protobuf import descriptor_pb2
File "/usr/local/lib/python2.7/dist-packages/google/protobuf/descriptor_pb2.py", line 1772, in <module>
  __module__ = 'google.protobuf.descriptor_pb2'
TypeError: A Message class can only inherit from Message

[AdrienDeliege]

I had the same problem with Spyder, which happened when it was trying to reload modules that were already loaded. I solved it by disabling the UMR (User Module Reloader) option in "preferences -> python interpreter" .

[Venkat-Rajgopal]

@AdrienDeliege That seems to be working for me.

[abramclark]

I'm having the same issue, but here's the bizarre part: it only happens in my wsgi app when requesting via SSL. I don't know how this could possibly make a difference to Python. I can't reproduce it on any other machine or from any other process except from an SSL request to apache2. My stack trace starts from my code at "from google.cloud.storage.client import Client" and ends with:

File "/usr/local/lib/python2.7/dist-packages/google/protobuf/duration_pb2.py", line 10,
in <module>
  from google.protobuf import descriptor_pb2
 File "/usr/local/lib/python2.7/dist-packages/google/protobuf/descriptor_pb2.py", line 1824, in <module>
  __module__ = 'google.protobuf.descriptor_pb2'
TypeError: A Message class can only inherit from Message

[chpohl]

@AdrienDeliege Also works for me, but I'd like to still use UMR. My current workaround is to add tensorflow to the UMR excluded modules under "preferences -> Console -> Advanced settings".

[diegolorenzetti]

For me what solved the problem was setting the line below on my Apache virtual host:

WSGIApplicationGroup %{GLOBAL}