Source code for grass.pygrass.modules.interface.module

from __future__ import (
    nested_scopes,
    generators,
    division,
    absolute_import,
    with_statement,
    print_function,
    unicode_literals,
)
import sys
from multiprocessing import cpu_count, Process, Queue
import time
from xml.etree.ElementTree import fromstring

from grass.exceptions import CalledModuleError, GrassError, ParameterError
from grass.script.core import Popen, PIPE, use_temp_region, del_temp_region
from grass.script.utils import encode, decode
from .docstring import docstring_property
from .parameter import Parameter
from .flag import Flag
from .typedict import TypeDict
from .read import GETFROMTAG, DOC
from .env import G_debug

if sys.version_info[0] == 2:
    from itertools import izip_longest as zip_longest
else:
    from itertools import zip_longest

    unicode = str


def _get_bash(self, *args, **kargs):
    return self.get_bash()


[docs]class ParallelModuleQueue(object): """This class is designed to run an arbitrary number of pygrass Module or MultiModule processes in parallel. Objects of type grass.pygrass.modules.Module or grass.pygrass.modules.MultiModule can be put into the queue using put() method. When the queue is full with the maximum number of parallel processes it will wait for all processes to finish, sets the stdout and stderr of the Module object and removes it from the queue when its finished. To finish the queue before the maximum number of parallel processes was reached call wait() . This class will raise a GrassError in case a Module process exits with a return code other than 0. Processes that were run asynchronously with the MultiModule class will not raise a GrassError in case of failure. This must be manually checked by accessing finished modules by calling get_finished_modules(). Usage: Check with a queue size of 3 and 5 processes >>> import copy >>> from grass.pygrass.modules import Module, MultiModule, ParallelModuleQueue >>> mapcalc_list = [] Setting run_ to False is important, otherwise a parallel processing is not possible >>> mapcalc = Module("r.mapcalc", overwrite=True, run_=False) >>> queue = ParallelModuleQueue(nprocs=3) >>> for i in range(5): ... new_mapcalc = copy.deepcopy(mapcalc) ... mapcalc_list.append(new_mapcalc) ... m = new_mapcalc(expression="test_pygrass_%i = %i"%(i, i)) ... queue.put(m) >>> queue.wait() >>> mapcalc_list = queue.get_finished_modules() >>> queue.get_num_run_procs() 0 >>> queue.get_max_num_procs() 3 >>> for mapcalc in mapcalc_list: ... print(mapcalc.returncode) 0 0 0 0 0 Check with a queue size of 8 and 5 processes >>> queue = ParallelModuleQueue(nprocs=8) >>> mapcalc_list = [] >>> for i in range(5): ... new_mapcalc = copy.deepcopy(mapcalc) ... mapcalc_list.append(new_mapcalc) ... m = new_mapcalc(expression="test_pygrass_%i = %i"%(i, i)) ... queue.put(m) >>> queue.wait() >>> mapcalc_list = queue.get_finished_modules() >>> queue.get_num_run_procs() 0 >>> queue.get_max_num_procs() 8 >>> for mapcalc in mapcalc_list: ... print(mapcalc.returncode) 0 0 0 0 0 Check MultiModule approach with three by two processes running in a background process >>> gregion = Module("g.region", flags="p", run_=False) >>> queue = ParallelModuleQueue(nprocs=3) >>> proc_list = [] >>> for i in range(3): ... new_gregion = copy.deepcopy(gregion) ... proc_list.append(new_gregion) ... new_mapcalc = copy.deepcopy(mapcalc) ... m = new_mapcalc(expression="test_pygrass_%i = %i"%(i, i)) ... proc_list.append(new_mapcalc) ... mm = MultiModule(module_list=[new_gregion, new_mapcalc], sync=False, set_temp_region=True) ... queue.put(mm) >>> queue.wait() >>> proc_list = queue.get_finished_modules() >>> queue.get_num_run_procs() 0 >>> queue.get_max_num_procs() 3 >>> for proc in proc_list: ... print(proc.returncode) 0 0 0 0 0 0 Check with a queue size of 8 and 4 processes >>> queue = ParallelModuleQueue(nprocs=8) >>> mapcalc_list = [] >>> new_mapcalc = copy.deepcopy(mapcalc) >>> mapcalc_list.append(new_mapcalc) >>> m = new_mapcalc(expression="test_pygrass_1 =1") >>> queue.put(m) >>> queue.get_num_run_procs() 1 >>> new_mapcalc = copy.deepcopy(mapcalc) >>> mapcalc_list.append(new_mapcalc) >>> m = new_mapcalc(expression="test_pygrass_2 =2") >>> queue.put(m) >>> queue.get_num_run_procs() 2 >>> new_mapcalc = copy.deepcopy(mapcalc) >>> mapcalc_list.append(new_mapcalc) >>> m = new_mapcalc(expression="test_pygrass_3 =3") >>> queue.put(m) >>> queue.get_num_run_procs() 3 >>> new_mapcalc = copy.deepcopy(mapcalc) >>> mapcalc_list.append(new_mapcalc) >>> m = new_mapcalc(expression="test_pygrass_4 =4") >>> queue.put(m) >>> queue.get_num_run_procs() 4 >>> queue.wait() >>> mapcalc_list = queue.get_finished_modules() >>> queue.get_num_run_procs() 0 >>> queue.get_max_num_procs() 8 >>> for mapcalc in mapcalc_list: ... print(mapcalc.returncode) 0 0 0 0 Check with a queue size of 3 and 4 processes >>> queue = ParallelModuleQueue(nprocs=3) >>> mapcalc_list = [] >>> new_mapcalc = copy.deepcopy(mapcalc) >>> mapcalc_list.append(new_mapcalc) >>> m = new_mapcalc(expression="test_pygrass_1 =1") >>> queue.put(m) >>> queue.get_num_run_procs() 1 >>> new_mapcalc = copy.deepcopy(mapcalc) >>> mapcalc_list.append(new_mapcalc) >>> m = new_mapcalc(expression="test_pygrass_2 =2") >>> queue.put(m) >>> queue.get_num_run_procs() 2 >>> new_mapcalc = copy.deepcopy(mapcalc) >>> mapcalc_list.append(new_mapcalc) >>> m = new_mapcalc(expression="test_pygrass_3 =3") >>> queue.put(m) # Now it will wait until all procs finish and set the counter back to 0 >>> queue.get_num_run_procs() 0 >>> new_mapcalc = copy.deepcopy(mapcalc) >>> mapcalc_list.append(new_mapcalc) >>> m = new_mapcalc(expression="test_pygrass_%i = %i"%(i, i)) >>> queue.put(m) >>> queue.get_num_run_procs() 1 >>> queue.wait() >>> mapcalc_list = queue.get_finished_modules() >>> queue.get_num_run_procs() 0 >>> queue.get_max_num_procs() 3 >>> for mapcalc in mapcalc_list: ... print(mapcalc.returncode) 0 0 0 0 """ def __init__(self, nprocs=1): """Constructor :param nprocs: The maximum number of Module processes that can be run in parallel, default is 1, if None then use all the available CPUs. :type nprocs: int """ nprocs = int(nprocs) if nprocs else cpu_count() self._num_procs = nprocs self._list = nprocs * [None] self._proc_count = 0 self._finished_modules = [] # Store all processed modules in a list
[docs] def put(self, module): """Put the next Module or MultiModule object in the queue To run the Module objects in parallel the run\_ and finish\_ options of the Module must be set to False. :param module: a preconfigured Module or MultiModule object that were configured with run\_ and finish\_ set to False, :type module: Module or MultiModule object """ self._list[self._proc_count] = module # Force that finish is False, otherwise the execution # will not be parallel self._list[self._proc_count].finish_ = False self._list[self._proc_count].run() self._proc_count += 1 if self._proc_count == self._num_procs: self.wait()
[docs] def get(self, num): """Get a Module object or list of Module objects from the queue :param num: the number of the object in queue :type num: int :returns: the Module object or list of Module objects or None if num is not in the queue """ if num < self._num_procs: return self._list[num] return None
[docs] def get_num_run_procs(self): """Get the number of Module processes that are in the queue running or finished :returns: the number fo Module processes running/finished in the queue """ return self._proc_count
[docs] def get_max_num_procs(self): """Return the maximum number of parallel Module processes :returns: the maximum number of parallel Module processes """ return self._num_procs
[docs] def set_max_num_procs(self, nprocs): """Set the maximum number of Module processes that should run in parallel :param nprocs: The maximum number of Module processes that can be run in parallel :type nprocs: int """ self._num_procs = int(nprocs) self.wait()
[docs] def get_finished_modules(self): """Return all finished processes that were run by this queue :return: A list of Module objects """ return self._finished_modules
[docs] def wait(self): """Wait for all Module processes that are in the list to finish and set the modules stdout and stderr output options :return: A list of modules that were run """ for proc in self._list: if proc: if isinstance(proc, Module): self._finished_modules.extend( [ proc.wait(), ] ) else: self._finished_modules.extend(proc.wait()) self._list = self._num_procs * [None] self._proc_count = 0
[docs]class Module(object): """This class is design to wrap/run/interact with the GRASS modules. The class during the init phase read the XML description generate using the ``--interface-description`` in order to understand which parameters are required which optionals. :: >>> from grass.pygrass.modules import Module >>> from subprocess import PIPE >>> import copy >>> region = Module("g.region") >>> region.flags.p = True # set flags >>> region.flags.u = True >>> region.flags["3"].value = True # set numeric flags >>> region.get_bash() 'g.region -p -3 -u' >>> new_region = copy.deepcopy(region) >>> new_region.inputs.res = "10" >>> new_region.get_bash() 'g.region res=10 -p -3 -u' >>> neighbors = Module("r.neighbors") >>> neighbors.inputs.input = "mapA" >>> neighbors.outputs.output = "mapB" >>> neighbors.inputs.size = 5 >>> neighbors.inputs.quantile = 0.5 >>> neighbors.get_bash() 'r.neighbors input=mapA size=5 method=average weighting_function=none quantile=0.5 nprocs=1 memory=300 output=mapB' >>> new_neighbors1 = copy.deepcopy(neighbors) >>> new_neighbors1.inputs.input = "mapD" >>> new_neighbors1.inputs.size = 3 >>> new_neighbors1.inputs.quantile = 0.5 >>> new_neighbors1.get_bash() 'r.neighbors input=mapD size=3 method=average weighting_function=none quantile=0.5 nprocs=1 memory=300 output=mapB' >>> new_neighbors2 = copy.deepcopy(neighbors) >>> new_neighbors2(input="mapD", size=3, run_=False) Module('r.neighbors') >>> new_neighbors2.get_bash() 'r.neighbors input=mapD size=3 method=average weighting_function=none quantile=0.5 nprocs=1 memory=300 output=mapB' >>> neighbors = Module("r.neighbors") >>> neighbors.get_bash() 'r.neighbors size=3 method=average weighting_function=none nprocs=1 memory=300' >>> new_neighbors3 = copy.deepcopy(neighbors) >>> new_neighbors3(input="mapA", size=3, output="mapB", run_=False) Module('r.neighbors') >>> new_neighbors3.get_bash() 'r.neighbors input=mapA size=3 method=average weighting_function=none nprocs=1 memory=300 output=mapB' >>> mapcalc = Module("r.mapcalc", expression="test_a = 1", ... overwrite=True, run_=False) >>> mapcalc.run() Module('r.mapcalc') >>> mapcalc.returncode 0 >>> mapcalc = Module("r.mapcalc", expression="test_a = 1", ... overwrite=True, run_=False, finish_=False) >>> mapcalc.run() Module('r.mapcalc') >>> p = mapcalc.wait() >>> p.returncode 0 >>> mapcalc.run() Module('r.mapcalc') >>> p = mapcalc.wait() >>> p.returncode 0 >>> colors = Module("r.colors", map="test_a", rules="-", ... run_=False, stdout_=PIPE, ... stderr_=PIPE, stdin_="1 red") >>> colors.run() Module('r.colors') >>> p = mapcalc.wait() >>> p.returncode 0 >>> colors.inputs["stdin"].value '1 red' >>> colors.outputs["stdout"].value '' >>> colors.outputs["stderr"].value.strip() "Color table for raster map <test_a> set to 'rules'" >>> colors = Module("r.colors", map="test_a", rules="-", ... run_=False, finish_=False, stdin_=PIPE) >>> colors.inputs["stdin"].value = "1 red" >>> colors.run() Module('r.colors') >>> colors.wait() Module('r.colors') >>> colors.returncode 0 >>> colors = Module("r.colors", map="test_a", rules="-", ... run_=False, finish_=False, ... stdin_=PIPE, stderr_=PIPE) >>> colors.inputs["stdin"].value = "1 red" >>> colors.run() Module('r.colors') >>> colors.wait() Module('r.colors') >>> colors.outputs["stderr"].value.strip() "Color table for raster map <test_a> set to 'rules'" >>> colors.returncode 0 Run a second time >>> colors.inputs["stdin"].value = "1 red" >>> colors.run() Module('r.colors') >>> colors.wait() Module('r.colors') >>> colors.outputs["stderr"].value.strip() "Color table for raster map <test_a> set to 'rules'" >>> colors.returncode 0 Run many times and change parameters for each run >>> colors = Module("r.colors", map="test_a", color="ryb", run_=False) >>> colors.get_bash() 'r.colors map=test_a color=ryb offset=0.0 scale=1.0' >>> colors.run() Module('r.colors') >>> colors.update(color="gyr") >>> colors.run() Module('r.colors') >>> colors.update(color="ryg") >>> colors.update(stderr_=PIPE) >>> colors.run() Module('r.colors') >>> print(colors.outputs["stderr"].value.strip()) Color table for raster map <test_a> set to 'ryg' >>> colors.update(color="byg") >>> colors.update(stdout_=PIPE) >>> colors.run() Module('r.colors') >>> print(colors.outputs["stderr"].value.strip()) Color table for raster map <test_a> set to 'byg' >>> colors.get_bash() 'r.colors map=test_a color=byg offset=0.0 scale=1.0' Often in the Module class you can find ``*args`` and ``kwargs`` annotation in methods, like in the __call__ method. Python allow developers to not specify all the arguments and keyword arguments of a method or function. :: def f(*args): for arg in args: print arg therefore if we call the function like: >>> f('grass', 'gis', 'modules') # doctest: +SKIP grass gis modules or we can define a new list: >>> words = ['grass', 'gis', 'modules'] # doctest: +SKIP >>> f(*words) # doctest: +SKIP grass gis modules we can do the same with keyword arguments, rewrite the above function: :: def f(*args, **kargs): for arg in args: print arg for key, value in kargs.items(): print "%s = %r" % (key, value) now we can use the new function, with: >>> f('grass', 'gis', 'modules', os = 'linux', language = 'python') ... # doctest: +SKIP grass gis modules os = 'linux' language = 'python' or, as before we can, define a dictionary and give the dictionary to the function, like: >>> keywords = {'os' : 'linux', 'language' : 'python'} # doctest: +SKIP >>> f(*words, **keywords) # doctest: +SKIP grass gis modules os = 'linux' language = 'python' In the Module class we heavily use this language feature to pass arguments and keyword arguments to the grass module. """ def __init__(self, cmd, *args, **kargs): if isinstance(cmd, unicode): self.name = str(cmd) elif isinstance(cmd, str): self.name = cmd else: raise GrassError("Problem initializing the module {s}".format(s=cmd)) try: # call the command with --interface-description get_cmd_xml = Popen([cmd, "--interface-description"], stdout=PIPE) except OSError as e: print("OSError error({0}): {1}".format(e.errno, e.strerror)) str_err = "Error running: `%s --interface-description`." raise GrassError(str_err % self.name) # get the xml of the module self.xml = get_cmd_xml.communicate()[0] # transform and parse the xml into an Element class: # http://docs.python.org/library/xml.etree.elementtree.html tree = fromstring(self.xml) for e in tree: if e.tag not in ("parameter", "flag"): self.__setattr__(e.tag, GETFROMTAG[e.tag](e)) # # extract parameters from the xml # self.params_list = [Parameter(p) for p in tree.findall("parameter")] self.inputs = TypeDict(Parameter) self.outputs = TypeDict(Parameter) self.required = [] # Insert parameters into input/output and required for par in self.params_list: if par.input: self.inputs[par.name] = par else: self.outputs[par.name] = par if par.required: self.required.append(par.name) # # extract flags from the xml # flags_list = [Flag(f) for f in tree.findall("flag")] self.flags = TypeDict(Flag) for flag in flags_list: self.flags[flag.name] = flag # # Add new attributes to the class # self.run_ = True self.finish_ = True self.check_ = True self.env_ = None self.stdin_ = None self.stdin = None self.stdout_ = None self.stderr_ = None diz = { "name": "stdin", "required": False, "multiple": False, "type": "all", "value": None, } self.inputs["stdin"] = Parameter(diz=diz) diz["name"] = "stdout" self.outputs["stdout"] = Parameter(diz=diz) diz["name"] = "stderr" self.outputs["stderr"] = Parameter(diz=diz) self._popen = None self.time = None self.start_time = None # This variable will be set in the run() function # This variable is set True if wait() was successfully called self._finished = False self.returncode = None if args or kargs: self.__call__(*args, **kargs) self.__call__.__func__.__doc__ = self.__doc__ def __call__(self, *args, **kargs): """Set module parameters to the class and, if run_ is True execute the module, therefore valid parameters are all the module parameters plus some extra parameters that are: run_, stdin_, stdout_, stderr_, env_ and finish_. """ if not args and not kargs: self.run() return self self.update(*args, **kargs) # # check if execute # if self.run_: # # check reqire parameters # if self.check_: self.check() return self.run() return self
[docs] def update(self, *args, **kargs): """Update module parameters and selected object attributes. Valid parameters are all the module parameters and additional parameters, namely: run_, stdin_, stdout_, stderr_, env_, and finish_. """ # # check for extra kargs, set attribute and remove from dictionary # if "flags" in kargs: for flg in kargs["flags"]: self.flags[flg].value = True del kargs["flags"] # set attributes for key in ("run_", "env_", "finish_", "stdout_", "stderr_", "check_"): if key in kargs: setattr(self, key, kargs.pop(key)) # set inputs for key in ("stdin_",): if key in kargs: self.inputs[key[:-1]].value = kargs.pop(key) # # set/update args # for param, arg in zip(self.params_list, args): param.value = arg for key, val in kargs.items(): key = key.strip("_") if key in self.inputs: self.inputs[key].value = val elif key in self.outputs: self.outputs[key].value = val elif key in self.flags: # we need to add this, because some parameters (overwrite, # verbose and quiet) work like parameters self.flags[key].value = val else: raise ParameterError("%s is not a valid parameter." % key)
[docs] def get_bash(self): """Return a BASH representation of the Module.""" return " ".join(self.make_cmd())
[docs] def get_python(self): """Return a Python representation of the Module.""" prefix = self.name.split(".")[0] name = "_".join(self.name.split(".")[1:]) params = ", ".join( [par.get_python() for par in self.params_list if par.get_python() != ""] ) flags = "".join( [ flg.get_python() for flg in self.flags.values() if not flg.special and flg.get_python() != "" ] ) special = ", ".join( [ flg.get_python() for flg in self.flags.values() if flg.special and flg.get_python() != "" ] ) # pre name par flg special if flags and special: return "%s.%s(%s, flags=%r, %s)" % (prefix, name, params, flags, special) elif flags: return "%s.%s(%s, flags=%r)" % (prefix, name, params, flags) elif special: return "%s.%s(%s, %s)" % (prefix, name, params, special) else: return "%s.%s(%s)" % (prefix, name, params)
def __str__(self): """Return the command string that can be executed in a shell""" return " ".join(self.make_cmd()) def __repr__(self): return "Module(%r)" % self.name @docstring_property(__doc__) def __doc__(self): """{cmd_name}({cmd_params})""" head = DOC["head"].format( cmd_name=self.name, # go to a new line # give space under the function name cmd_params=("\n" + (" " * (len(self.name) + 1))).join( [ ", ".join( # transform each parameter in string [str(param) for param in line if param is not None] ) # make a list of parameters with only 3 param per line for line in zip_longest(*[iter(self.params_list)] * 3) ] ), ) params = "\n".join([par.__doc__ for par in self.params_list]) flags = self.flags.__doc__ return "\n".join([head, params, DOC["flag_head"], flags, DOC["foot"]])
[docs] def check(self): """Check the correctness of the provide parameters""" required = True for flg in self.flags.values(): if flg and flg.suppress_required: required = False if required: for k in self.required: if (k in self.inputs and self.inputs[k].value is None) or ( k in self.outputs and self.outputs[k].value is None ): msg = "Required parameter <%s> not set." raise ParameterError(msg % k)
[docs] def get_dict(self): """Return a dictionary that includes the name, all valid inputs, outputs and flags """ dic = {} dic["name"] = self.name dic["inputs"] = [(k, v.value) for k, v in self.inputs.items() if v.value] dic["outputs"] = [(k, v.value) for k, v in self.outputs.items() if v.value] dic["flags"] = [flg for flg in self.flags if self.flags[flg].value] return dic
[docs] def make_cmd(self): """Create the command string that can be executed in a shell :returns: the command string """ skip = ["stdin", "stdout", "stderr"] args = [ self.name, ] for key in self.inputs: if ( key not in skip and self.inputs[key].value is not None and self.inputs[key].value != "" ): args.append(self.inputs[key].get_bash()) for key in self.outputs: if ( key not in skip and self.outputs[key].value is not None and self.outputs[key].value != "" ): args.append(self.outputs[key].get_bash()) for flg in self.flags: if self.flags[flg].value: args.append(str(self.flags[flg])) return args
[docs] def run(self): """Run the module This function will wait for the process to terminate in case finish_==True and sets up stdout and stderr. If finish_==False this function will return after starting the process. Use wait() to wait for the started process :return: A reference to this object """ G_debug(1, self.get_bash()) self._finished = False if self.inputs["stdin"].value: self.stdin = self.inputs["stdin"].value self.stdin_ = PIPE cmd = self.make_cmd() self.start_time = time.time() self._popen = Popen( cmd, stdin=self.stdin_, stdout=self.stdout_, stderr=self.stderr_, env=self.env_, ) if self.finish_ is True: self.wait() return self
[docs] def wait(self): """Wait for the module to finish. Call this method if the run() call was performed with self.false_ = False. :return: A reference to this object """ if self._finished is False: if self.stdin: self.stdin = encode(self.stdin) stdout, stderr = self._popen.communicate(input=self.stdin) self.outputs["stdout"].value = decode(stdout) if stdout else "" self.outputs["stderr"].value = decode(stderr) if stderr else "" self.time = time.time() - self.start_time self.returncode = self._popen.returncode self._finished = True if self._popen.poll(): raise CalledModuleError( returncode=self._popen.returncode, code=self.get_bash(), module=self.name, errors=stderr, ) self._popen = None return self
[docs]class MultiModule(object): """This class is designed to run a list of modules in serial in the provided order within a temporary region environment. Module can be run in serial synchronously or asynchronously. - Synchronously: When calling run() all modules will run in serial order until they are finished, The run() method will return until all modules finished. The modules objects can be accessed by calling get_modules() to check their return values. - Asynchronously: When calling run() all modules will run in serial order in a background process. Method run() will return after starting the modules without waiting for them to finish. The user must call the wait() method to wait for the modules to finish. Asynchronously called module can be optionally run in a temporary region environment, hence invokeing g.region will not alter the current region or the region of other MultiModule runs. Note: Modules run in asynchronous mode can only be accessed via the wait() method. The wait() method will return all finished module objects as list. Objects of this class can be passed to the ParallelModuleQueue to run serial stacks of modules in parallel. This is meaningful if region settings must be applied to each parallel module run. >>> from grass.pygrass.modules import Module >>> from grass.pygrass.modules import MultiModule >>> from multiprocessing import Process >>> import copy Synchronous module run >>> region_1 = Module("g.region", run_=False) >>> region_1.flags.p = True >>> region_2 = copy.deepcopy(region_1) >>> region_2.flags.p = True >>> mm = MultiModule(module_list=[region_1, region_2]) >>> mm.run() >>> m_list = mm.get_modules() >>> m_list[0].returncode 0 >>> m_list[1].returncode 0 Asynchronous module run, setting finish = False >>> region_1 = Module("g.region", run_=False) >>> region_1.flags.p = True >>> region_2 = copy.deepcopy(region_1) >>> region_2.flags.p = True >>> region_3 = copy.deepcopy(region_1) >>> region_3.flags.p = True >>> region_4 = copy.deepcopy(region_1) >>> region_4.flags.p = True >>> region_5 = copy.deepcopy(region_1) >>> region_5.flags.p = True >>> mm = MultiModule(module_list=[region_1, region_2, region_3, region_4, region_5], ... sync=False) >>> t = mm.run() >>> isinstance(t, Process) True >>> m_list = mm.wait() >>> m_list[0].returncode 0 >>> m_list[1].returncode 0 >>> m_list[2].returncode 0 >>> m_list[3].returncode 0 >>> m_list[4].returncode 0 Asynchronous module run, setting finish = False and using temporary region >>> mm = MultiModule(module_list=[region_1, region_2, region_3, region_4, region_5], ... sync=False, set_temp_region=True) >>> str(mm) 'g.region -p ; g.region -p ; g.region -p ; g.region -p ; g.region -p' >>> t = mm.run() >>> isinstance(t, Process) True >>> m_list = mm.wait() >>> m_list[0].returncode 0 >>> m_list[1].returncode 0 >>> m_list[2].returncode 0 >>> m_list[3].returncode 0 >>> m_list[4].returncode 0 """ def __init__(self, module_list, sync=True, set_temp_region=False): """Constructor of the multi module class :param module_list: A list of pre-configured Module objects that should be run :param sync: If set True the run() method will wait for all processes to finish -> synchronously run. If set False, the run() method will return after starting the processes -> asynchronously run. The wait() method must be called to finish the modules. :param set_temp_region: Set a temporary region in which the modules should be run, hence region settings in the process list will not affect the current computation region. Note: This flag is only available in asynchronous mode! :return: """ self.module_list = module_list self.set_temp_region = set_temp_region self.finish_ = sync # We use the same variable name a Module self.p = None self.q = Queue() def __str__(self): """Return the command string that can be executed in a shell""" return " ; ".join(str(string) for string in self.module_list)
[docs] def get_modules(self): """Return the list of modules that have been run in synchronous mode Note: Asynchronously run module can only be accessed via the wait() method. :return: The list of modules """ return self.module_list
[docs] def run(self): """Start the modules in the list. If self.finished_ is set True this method will return after all processes finished. If self.finish_ is set False, this method will return after the process list was started for execution. In a background process, the processes in the list will be run one after the another. :return: None in case of self.finish_ is True, otherwise a multiprocessing.Process object that invokes the modules """ if self.finish_ is True: for module in self.module_list: module.finish_ = True module.run() return None else: if self.set_temp_region is True: self.p = Process( target=run_modules_in_temp_region, args=[self.module_list, self.q] ) else: self.p = Process(target=run_modules, args=[self.module_list, self.q]) self.p.start() return self.p
[docs] def wait(self): """Wait for all processes to finish. Call this method in asynchronous mode, hence if finished was set False. :return: The process list with finished processes to check their return states """ if self.p: proc_list = self.q.get() self.p.join() return proc_list
[docs]def run_modules_in_temp_region(module_list, q): """Run the modules in a temporary region environment This function is the argument for multiprocessing.Process class in the MultiModule asynchronous execution. :param module_list: The list of modules to run in serial :param q: The process queue to put the finished process list """ use_temp_region() try: for proc in module_list: proc.run() proc.wait() finally: q.put(module_list) del_temp_region()
[docs]def run_modules(module_list, q): """Run the modules This function is the argument for multiprocessing.Process class in the MultiModule asynchronous execution. :param module_list: The list of modules to run in serial :param q: The process queue to put the finished process list """ try: for proc in module_list: proc.run() proc.wait() finally: q.put(module_list)
############################################################################### if __name__ == "__main__": import doctest doctest.testmod()