Fix post_mortem Spock's magic command

[reszelaz]

post_mortem magic command has two problems:

• is unable to read Door stream attributes and always fallback to the buffered logs. Fix it by making the Attr class capable to read, from cache or from the device, attribute values.
• door stream buffer is cleared when macro finishes and in case of server crash these needs to be kept. Fix it by clearing buffer at the next macro startup

@cmft could you please test it? Many thanks!

[cmft]

Hi @reszelaz ,
This fix does not solve at all the issue. In case taurus can not resolve the name another exception is raising.

 showscan foo
MainThread     INFO     2021-09-23 15:13:23,983 TaurusRootLogger: Using PyQt5 (v5.12.3 with Qt 5.12.9 and Python 3.9.6)
MainThread     WARNING  2021-09-23 15:13:25,100 TaurusRootLogger: Problem with taurus.qt.editor (hint: is spyder >=3 installed?)
Traceback (most recent call last):
  File "/home/cfalcon/miniconda/envs/testing/bin/showscan", line 33, in <module>
    sys.exit(load_entry_point('sardana', 'console_scripts', 'showscan')())
  File "/home/cfalcon/miniconda/envs/testing/lib/python3.9/site-packages/click/core.py", line 1137, in __call__
    return self.main(*args, **kwargs)
  File "/home/cfalcon/miniconda/envs/testing/lib/python3.9/site-packages/click/core.py", line 1062, in main
    rv = self.invoke(ctx)
  File "/home/cfalcon/miniconda/envs/testing/lib/python3.9/site-packages/click/core.py", line 1404, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/home/cfalcon/miniconda/envs/testing/lib/python3.9/site-packages/click/core.py", line 763, in invoke
    return __callback(*args, **kwargs)
  File "/home/cfalcon/tools/sardana/src/sardana/taurus/qt/qtgui/extra_sardana/showscanonline.py", line 323, in main
    widget.setModel(door)
  File "/home/cfalcon/tools/sardana/src/sardana/taurus/qt/qtgui/extra_sardana/showscanonline.py", line 239, in setModel
    door = taurus.Device(model)
  File "/home/cfalcon/tools/taurus/lib/taurus/_taurushelper.py", line 260, in Device
    return Factory(scheme=getSchemeFromName(device_name)).getDevice(
  File "/home/cfalcon/tools/taurus/lib/taurus/core/tango/tangofactory.py", line 373, in getDevice
    raise TaurusException("Cannot find full name of '%s'" % dev_name)
taurus.core.taurusexception.TaurusException: Cannot find full name of 'foo'

[reszelaz]

Thanks for the test. However I think you have mixed the PRs. The test you have performed is related to the #1676.

[cmft]

Sorry, You right. I reported the issue in a wrong ticket

[cmft]

Test report

Door_cfalcon_1 [1]: %post_mortem # server alive
<- init_device

Door_cfalcon_1 [2]: %post_mortem #server down
------------------------------
Server is offline.
This is a post mortem analysis
------------------------------
<- init_device

Door_cfalcon_1 [3]: %post_mortem # server stopped 
TaurusPollingTimer[3000] WARNING  2021-11-02 08:48:32,103 TaurusPollingTimer[3000]: loop function took more than loop interval (3.0s)
------------------------------
Server is offline.
This is a post mortem analysis
------------------------------
<- init_device

Run macro and kill MS

Door_cf_1 [3]: ct 10
Tue Nov 02 10:30:39 2021



Door_cf_1 (OFFLINE) [4]: 

Door_cf_1 (OFFLINE) [4]: %post_mortem
------------------------------
Server is offline.
This is a post mortem analysis
------------------------------
[START] runMacro Macro 'ct(10.0, None) -> 8afe0101-3bbf-11ec-89d0-d89ef310e736'
Counting for 10.0 sec

So, it seems ok for me

[reszelaz]

@cmft thanks for your efforts to test it. I'm merging.