[GRASS-dev] [GRASS GIS] #2709: pyGRASS Module runs twice from interactive Python prompt

[GRASS GIS]

#2709: pyGRASS Module runs twice from interactive Python prompt
--------------------------+--------------------------------
  Reporter:  martinl      |      Owner:
      Type:  defect       |     Status:  new
  Priority:  major        |  Milestone:  7.0.4
 Component:  PyGRASS      |    Version:  unspecified
Resolution:               |   Keywords:  interactive prompt
       CPU:  Unspecified  |   Platform:  Linux
--------------------------+--------------------------------

Comment (by zarch):

 Hi Markus,

 Replying to [comment:6 neteler]:
 > {{{
 > GRASS 7.1.svn (eu_laea):~ > python
 > Python 2.7.10 (default, Sep  8 2015, 17:20:17)
 > [GCC 5.1.1 20150618 (Red Hat 5.1.1-4)] on linux2
 > Type "help", "copyright", "credits" or "license" for more information.
 > >>> from grass.pygrass.modules import Module
 > >>> Module('g.extension', flags='a')
 > List of installed extensions (modules):
 > r.skyview
 > i.segment.hierarchical
 > Module('g.extension')                 <<== ????
 > }}}

 This is right, things are clearer using ipython:


 {{{
 In [1]: from grass.pygrass.modules import Module

 In [2]: Module('g.extension', flags='a')
 No extension (module) installed
 Out[2]: Module('g.extension')
 }}}

 the python shell does not differentiate between print in stdout/stderr
 (generate by the execution of module) and the representation of the
 object.
 The line Out[2] is returning the instance of the Module class.

 If you are bothering by this just save the instance into a variable:

 {{{
 In [3]: gext = Module('g.extension', flags='a')
 No extension (module) installed
 }}}

 > Anyway, now entering the next command from the original report:
 >
 > {{{
 > >>> Module('r.mask', flags='r')
 > ERROR: No existing MASK to remove
 >
 > [cut]
 >
 >     msg = _("Module run %s %s ended with error") % (module, code)
 >   File "/home/neteler/software/grass71/dist.x86_64-pc-linux-
 gnu/etc/python/grass/pygrass/modules/interface/module.py", line 583, in
 __call__
 >     return self.run()
 >   File "/home/neteler/software/grass71/dist.x86_64-pc-linux-
 gnu/etc/python/grass/pygrass/modules/interface/module.py", line 706, in
 run
 >     stdout, stderr = self.popen.communicate(input=self.stdin)
 >   File "/usr/lib64/python2.7/subprocess.py", line 796, in communicate
 >     self.wait()
 >   File "/usr/lib64/python2.7/subprocess.py", line 1384, in wait
 >     pid, sts = _eintr_retry_call(os.waitpid, self.pid, 0)
 >   File "/usr/lib64/python2.7/subprocess.py", line 476, in
 _eintr_retry_call
 >     return func(*args)
 > KeyboardInterrupt
 > }}}

 Ipython does not soffer by this strange behavior and it works well.

 {{{
 In [4]: Module('r.mask', flags='r')
 ERROR: No existing MASK to remove
 ---------------------------------------------------------------------------
 CalledModuleError                         Traceback (most recent call
 last)
 <ipython-input-4-217f55a3bd88> in <module>()
 ----> 1 rmsk = Module('r.mask', flags='r')

 /home/pietro/docdat/src/gis/grass71/dist.x86_64-pc-linux-
 gnu/etc/python/grass/pygrass/modules/interface/module.pyc in
 __init__(self, cmd, *args, **kargs)
     524
     525         if args or kargs:
 --> 526             self.__call__(*args, **kargs)
     527         self.__call__.__func__.__doc__ = self.__doc__
     528

 /home/pietro/docdat/src/gis/grass71/dist.x86_64-pc-linux-
 gnu/etc/python/grass/pygrass/modules/interface/module.pyc in
 __call__(self, *args, **kargs)
     581             if self.check_:
     582                 self.check()
 --> 583             return self.run()
     584         return self
     585

 /home/pietro/docdat/src/gis/grass71/dist.x86_64-pc-linux-
 gnu/etc/python/grass/pygrass/modules/interface/module.pyc in run(self)
     711                 raise
 CalledModuleError(returncode=self.popen.returncode,
     712                                         code=self.get_bash(),
 --> 713                                         module=self.name,
 errors=stderr)
     714         return self
     715

 CalledModuleError: Module run r.mask r.mask maskcats=* layer=1 -r ended
 with error
 Process ended with non-zero return code 1. See errors in the (error)
 output.
 }}}

 No idea on why is not working properly in the standard python shell.

 Just for the record it is working under python3...

 {{{
 Python 3.5.1 (default, Dec  7 2015, 12:58:09)
 [GCC 5.2.0] on linux
 Type "help", "copyright", "credits" or "license" for more information.
 >>> from grass.pygrass.modules import Module
 >>> Module('r.mask', flags='r')
 ERROR: No existing MASK to remove
 Traceback (most recent call last):
   File "<stdin>", line 1, in <module>
   File "/home/pietro/docdat/src/gis/grass71/dist.x86_64-pc-linux-
 gnu/etc/python/grass/pygrass/modules/interface/module.py", line 526, in
 __init__
     self.__call__(*args, **kargs)
   File "/home/pietro/docdat/src/gis/grass71/dist.x86_64-pc-linux-
 gnu/etc/python/grass/pygrass/modules/interface/module.py", line 583, in
 __call__
     return self.run()
   File "/home/pietro/docdat/src/gis/grass71/dist.x86_64-pc-linux-
 gnu/etc/python/grass/pygrass/modules/interface/module.py", line 713, in
 run
     module=self.name, errors=stderr)
 grass.exceptions.CalledModuleError: Module run r.mask r.mask maskcats=*
 layer=1 -r ended with error
 Process ended with non-zero return code 1. See errors in the (error)
 output.
 }}}

--
Ticket URL: <https://trac.osgeo.org/grass/ticket/2709#comment:7>
GRASS GIS <https://grass.osgeo.org>