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Mkwrapper Stop block: ModuleNotFoundError: No module named 'preview' #8
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I had some similar module not found issues with my python configs in the fdm folder
I got module errors in the base.py filebefore i changed the lines from:
import rcomps import storage import motionto:
from fdm.config import rcomps from fdm.config import storage from fdm.config import motionLike python 3.7 handles local paths different ?
- changed the title
[-]Mklauncher Stop block: ModuleNotFoundError: No module named 'preview'[/-][+]Mkwrapper Stop block: ModuleNotFoundError: No module named 'preview'[/+]on Oct 25, 2020 This is not a python 2/3 issue:
I revived my Emcapp python2 setup with this patch specified here and the problem persists:
( I even tried copying over an old mkwrapper from my running machinekit-cnc ox-router setup, same result)/usr/lib/python2.7/dist-packages/pyftpdlib/authorizers.py:244: RuntimeWarning: write permissions assigned to anonymous user. RuntimeWarning) Process Process-1: Traceback (most recent call last): File "/usr/lib/python2.7/multiprocessing/process.py", line 267, in _bootstrap self.run() File "/usr/lib/python2.7/multiprocessing/process.py", line 114, in run self._target(*self._args, **self._kwargs) File "/usr/bin/mkwrapper", line 322, in run import preview # must be imported in new process to work properly ImportError: No module named preview@cerna
Can this have something to do with how the python include/search paths are setup in Linuxcnc differing from Machinekit-cnc ?Poking around in my old ob-ox setup I can find out where the preview comes from there:
machinekit@mksocfpga-ob-ox:~$ python Python 2.7.13 (default, Aug 22 2020, 10:03:02) [GCC 6.3.0 20170516] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> import preview >>> preview.__file__ '/usr/lib/python2.7/dist-packages/preview.so' >>> exit() preview: socket shutdown machinekit@mksocfpga-ob-ox:~$ cat /etc/*-release PRETTY_NAME="Debian GNU/Linux 9 (stretch)" NAME="Debian GNU/Linux" VERSION_ID="9" VERSION="9 (stretch)" VERSION_CODENAME=stretch ID=debian HOME_URL="https://www.debian.org/" SUPPORT_URL="https://www.debian.org/support" BUG_REPORT_URL="https://bugs.debian.org/"And find out that its missing in my newest setup:
machinekit@mksocfpga-ultra-soc:~/Hm2-soc_FDM/Cramps/HAL/ULTRA$ python Python 2.7.16 (default, Oct 10 2019, 22:02:15) [GCC 8.3.0] on linux2 Type "help", "copyright", "credits" or "license" for more information. >>> import preview Traceback (most recent call last): File "<stdin>", line 1, in <module> ImportError: No module named preview >>> exit() machinekit@mksocfpga-ultra-soc:~/Hm2-soc_FDM/Cramps/HAL/ULTRA$ cat /etc/*-release PRETTY_NAME="Debian GNU/Linux 10 (buster)" NAME="Debian GNU/Linux" VERSION_ID="10" VERSION="10 (buster)" VERSION_CODENAME=buster ID=debian HOME_URL="https://www.debian.org/" SUPPORT_URL="https://www.debian.org/support" BUG_REPORT_URL="https://bugs.debian.org/"However struggling to find out where the:
'/usr/lib/python2.7/dist-packages/preview.so'file is fromWell I can find it in the (from machinekit.io)
machinekit-cnc-rt-preempt_0.1.1553365560.git3686a54-1_stretch_armhf.deb
Still struggling to find out how its compiledThe preview module is compiled in from:
https://github.com/machinekit/machinekit-cnc/blob/master/src/emc/rs274ngc/Submakefile#L77-L87The whole compile blob shows it to depend on haltalk, czmq and the protobuff stuff:
PREVIEWMODULESRCS := \ emc/rs274ngc/previewmodule.cc PYSRCS += $(PREVIEWMODULESRCS) $(call TOOBJSDEPS, $(PREVIEWMODULESRCS)) : Makefile.inc $(call TOOBJSDEPS, $(PREVIEWMODULESRCS)) : EXTRAFLAGS += -Ihal/haltalk $(CZMQ_CFLAGS) $(PROTOBUF_CFLAGS) PREVIEWMODULE := ../lib/python/preview.so $(PREVIEWMODULE): $(call TOOBJS, $(PREVIEWMODULESRCS)) \ ../lib/librs274.so.0 \ ../lib/libmachinetalk-pb2++.so.0 \ ../lib/libmtalk.so $(ECHO) Linking python module $(notdir $@) $(Q)$(CXX) $(LDFLAGS) -shared -o $@ $^ -lstdc++ $(CZMQ_LIBS) \ $(PROTOBUF_LIBS) PYTARGETS += $(PREVIEWMODULE)@cerna
I'm not sure if the QtQuickvcp repo would be the natural place to compile this code in from. Comes to mind a more natural place would be a haltalk repo based on this folder.I'm able to get the preview.so to compile in machinekit-hal however
I'm unable to get past this issue:ImportError: /usr/lib/librs274.so.0: undefined symbol: _Z18GET_EXTERNAL_SPEEDi/usr/lib/python2.7/dist-packages/pyftpdlib/authorizers.py:244: RuntimeWarning: write permissions assigned to anonymous user. RuntimeWarning) Process Process-1: Traceback (most recent call last): File "/usr/lib/python2.7/multiprocessing/process.py", line 267, in _bootstrap self.run() File "/usr/lib/python2.7/multiprocessing/process.py", line 114, in run self._target(*self._args, **self._kwargs) File "/usr/bin/mkwrapper", line 322, in run import preview # must be imported in new process to work properly ImportError: /usr/lib/librs274.so.0: undefined symbol: _Z18GET_EXTERNAL_SPEEDi ^Cstopping mklauncher... done stopping configserver... done stopping linuxcnc... task: 3456 cycles, min=0.000134, max=0.010570, avg=0.010017, 0 latency excursions (> 10x expected cycle time of 0.010000s) exiting HAL component storage done$ c++filt _Z18GET_EXTERNAL_SPEEDi GET_EXTERNAL_SPEED(int)Turns out I needed to use the files from the Emc app src/emc folder instead of the ones from mk-cnc and update previewmodule.cc
via looking at the gcodemodule.cc file from emc app.
The "patches" are currently in 2 separate branches: arm64 armhf
These patches are for preview only and intended as somthing to copy and paste from (ie. previewmodule.cc)Results running in machinekit-client service view:
There are 4 services missing compared to a correctly running instance:
HAL Rcommand service HAL Rcomp service HAL Group service Log servicerunning the gui (MachinekitClient) gives following execption:
Exception in thread process_sockets: Traceback (most recent call last): File "/usr/lib/python2.7/threading.py", line 801, in __bootstrap_inner self.run() File "/usr/lib/python2.7/threading.py", line 754, in run self.__target(*self.__args, **self.__kwargs) File "/usr/bin/mkwrapper", line 678, in process_sockets self.update_status(self.stat) File "/usr/bin/mkwrapper", line 1758, in update_status self.update_motion(stat) File "/usr/bin/mkwrapper", line 1510, in update_motion modified |= self.update_motion_value(name, getattr(stat, name)) AttributeError: 'linuxcnc.stat' object has no attribute 'spindle_brake'Looks like mkwrapper needs to be updated to the linuxcnc 2.8 , 2.9 changes:
axis --> joints
motion.spindle.xx --> spindle..xxThis exception seems to be caused by mkwrapper not being updated to the new lcnc axis --> joints update in 2.8 , 2.9.
A way to see the changes needed seem to be to compare emctaskmain.cc from machinekit-cnc to emcapp
Also same update seems to be needed to the protobuf stuff here
By editing mkwrapper.py and status.proto I'm finally able to get the Cetus gui to start up execpt for now all the spindle stuff is commented out.
I'm able to get my machine to home however when I try to jog I get this:/usr/lib/python2.7/dist-packages/pyftpdlib/authorizers.py:244: RuntimeWarning: write permissions assigned to anonymous user. RuntimeWarning) ERROR: uncaught exception integer argument expected, got float ERROR: uncaught exception function takes at least 3 arguments (2 given)Got my machine to jog with standard Cetus Gui
Turns out the jog functions in mkwrapper needed an extra jogmode parameter.
Now I get this in Cetus: (after some homing and jogging)must be in joint mode to homeSorry I was unaccounted for the party, had to prioritize my engagements.
Can this have something to do with how the python include/search paths are setup in Linuxcnc differing from Machinekit-cnc ?
My first reaction is to probably delegate it to its own repository. I think it is a better solution to have multiple smallish project with limited functionality than one big doing-it-all. (Mainly because of the dependency graph and maintenance issues stemming from it.)
Can this have something to do with how the python include/search paths are setup in Linuxcnc differing from Machinekit-cnc ?
I am not sure, but I don't think so.(?) All Python packages for Machinekit projects and for LinuxCNC (as far as I know) are comming from apt Debian repository, which installs it in one place. There is no use of _Virtual Environment_s or Pyenv, because combining it with Debian packaging is extremely painful. (And it would make more sense to try something like Nix anyway.)
There could be a dichotomy between Python2.x and Python3 version of packages.
All in all, it's great that you were able to reach the bottom of it! 👍
However struggling to find out where the: '/usr/lib/python2.7/dist-packages/preview.so' file is from
My personal opinion on this issue is that all compiled files (here shared libraries) should have a prefix identifying it as a Machinekit file (
mkh_,mkemca_,mkcnc_and so on) and maybe some binary header.Got my machine to jog with standard Cetus Gui Turns out the jog functions in mkwrapper needed an extra jogmode parameter. Now I get this in Cetus: (after some homing and jogging)
must be in joint mode to homeThis is not a python 2/3 issue: I revived my Emcapp python2 setup with this patch specified here and the problem persists: ( I even tried copying over an old mkwrapper from my running machinekit-cnc ox-router setup, same result)
/usr/lib/python2.7/dist-packages/pyftpdlib/authorizers.py:244: RuntimeWarning: write permissions assigned to anonymous user. RuntimeWarning) Process Process-1: Traceback (most recent call last): File "/usr/lib/python2.7/multiprocessing/process.py", line 267, in _bootstrap self.run() File "/usr/lib/python2.7/multiprocessing/process.py", line 114, in run self._target(*self._args, **self._kwargs) File "/usr/bin/mkwrapper", line 322, in run import preview # must be imported in new process to work properly ImportError: No module named preview@cerna Can this have something to do with how the python include/search paths are setup in Linuxcnc differing from Machinekit-cnc ?
Hello, I also encountered the same problem, how did you solve it?
@summerlotus513
Try looking at my latest attempts to fix the mkwrapper qtquickvcp stuff here:
https://github.com/the-snowwhite/machinekit-hal/commits/mkwrapper_proto_work-py3
and here:
https://github.com/the-snowwhite/EMCApplication/commits/python3
The whole premise in this thread is to see:
A Is it possible to get the qtquickvcp gui's running by adding the missing preview.so lib ?
Edit: Answer: allmost
B.Find out what else is missing.
Edit Answer at bottom
Based on this suggestion
I compiled Emcapp with full python 3 support using this method:
Then tested the axis sim config: ran without any problems execpt this message:
Mkwrapper:
I used the newest package from machinekit-hal on purpose.
I used this hal config updated for linuxcnc 2.9 (and the newest added soc)
I have a similar version that is tested to work with the compiled in axis gui.
Here is the result of a python3 ./run.py run:
Seems like config is parsed ok however mkwrapper cannot fínd the module preview.
I wonder where this python preview module requested here is supposed to come from.
BTW
With these changes to the linuxcnc script
Im able to run a similar python based hal config
however the end result is the same error traceback