# -*- coding: utf-8 -*- """ *************************************************************************** GeoAlgorithm.py --------------------- Date : August 2012 Copyright : (C) 2012 by Victor Olaya Email : volayaf at gmail dot com *************************************************************************** * * * This program is free software; you can redistribute it and/or modify * * it under the terms of the GNU General Public License as published by * * the Free Software Foundation; either version 2 of the License, or * * (at your option) any later version. * * * *************************************************************************** """ __author__ = 'Victor Olaya' __date__ = 'August 2012' __copyright__ = '(C) 2012, Victor Olaya' # This will get replaced with a git SHA1 when you do a git archive __revision__ = '$Format:%H$' from builtins import str from builtins import object import os.path import traceback import subprocess import copy from qgis.PyQt.QtCore import QCoreApplication from qgis.core import (QgsProcessingFeedback, QgsSettings, QgsProcessingAlgorithm, QgsProject, QgsProcessingUtils, QgsProcessingParameterDefinition, QgsMessageLog) from qgis.gui import QgsHelp from processing.core.ProcessingConfig import ProcessingConfig from processing.core.GeoAlgorithmExecutionException import GeoAlgorithmExecutionException from processing.core.parameters import ParameterRaster, ParameterVector, ParameterMultipleInput, ParameterTable, Parameter from processing.core.outputs import OutputVector, OutputRaster, OutputTable, OutputHTML, Output from processing.algs.gdal.GdalUtils import GdalUtils from processing.tools import dataobjects class GeoAlgorithm(QgsProcessingAlgorithm): def __init__(self): super().__init__() # Outputs generated by the algorithm self.outputs = list() # The crs taken from input layers (if possible), and used when # loading output layers self.crs = None # If the algorithm is run as part of a model, the parent model # can be set in this variable, to allow for customized # behavior, in case some operations should be run differently # when running as part of a model self.model = None # methods to overwrite when creating a custom geoalgorithm def processAlgorithm(self, parameters, context, feedback): """Here goes the algorithm itself. There is no return value from this method. A GeoAlgorithmExecutionException should be raised in case something goes wrong. :param parameters: :param context: """ pass def getCustomModelerParametersDialog(self, modelAlg, algName=None): """If the algorithm has a custom parameters dialog when called from the modeler, it should be returned here, ready to be executed. """ return None def processBeforeAddingToModeler(self, alg, model): """Add here any task that has to be performed before adding an algorithm to a model, such as changing the value of a parameter depending on value of another one""" pass # ========================================================= def execute(self, parameters, context=None, feedback=None, model=None): """The method to use to call a processing algorithm. Although the body of the algorithm is in processAlgorithm(), it should be called using this method, since it performs some additional operations. Raises a GeoAlgorithmExecutionException in case anything goes wrong. :param parameters: """ if feedback is None: feedback = QgsProcessingFeedback() if context is None: context = dataobjects.createContext(feedback) self.model = model try: self.setOutputCRS() self.resolveOutputs() self.runPreExecutionScript(feedback) self.processAlgorithm(parameters, context, feedback) feedback.setProgress(100) self.convertUnsupportedFormats(context, feedback) self.runPostExecutionScript(feedback) except GeoAlgorithmExecutionException as gaee: lines = [self.tr('Error while executing algorithm')] lines.append(traceback.format_exc()) QgsMessageLog.logMessage(gaee.msg, self.tr('Processing'), QgsMessageLog.CRITICAL) raise GeoAlgorithmExecutionException(gaee.msg, lines, gaee) except Exception as e: # If something goes wrong and is not caught in the # algorithm, we catch it here and wrap it lines = [self.tr('Uncaught error while executing algorithm')] lines.append(traceback.format_exc()) QgsMessageLog.logMessage('\n'.join(lines), self.tr('Processing'), QgsMessageLog.CRITICAL) raise GeoAlgorithmExecutionException(str(e) + self.tr('\nSee log for more details'), lines, e) def runPostExecutionScript(self, feedback): scriptFile = ProcessingConfig.getSetting( ProcessingConfig.POST_EXECUTION_SCRIPT) self.runHookScript(scriptFile, feedback) def runPreExecutionScript(self, feedback): scriptFile = ProcessingConfig.getSetting( ProcessingConfig.PRE_EXECUTION_SCRIPT) self.runHookScript(scriptFile, feedback) def runHookScript(self, filename, feedback): if filename is None or not os.path.exists(filename): return try: script = 'import processing\n' ns = {} ns['feedback'] = feedback ns['alg'] = self with open(filename) as f: lines = f.readlines() for line in lines: script += line exec(script, ns) except Exception as e: QgsMessageLog.logMessage("Error in hook script: " + str(e), self.tr('Processing'), QgsMessageLog.WARNING) # A wrong script should not cause problems, so we swallow # all exceptions pass def convertUnsupportedFormats(self, context, feedback): i = 0 feedback.setProgressText(self.tr('Converting outputs')) for out in self.outputs: if isinstance(out, OutputVector): if out.compatible is not None: layer = QgsProcessingUtils.mapLayerFromString(out.compatible, context) if layer is None: # For the case of memory layer, if the # getCompatible method has been called continue writer = out.getVectorWriter(layer.fields(), layer.wkbType(), layer.crs(), context) features = QgsProcessingUtils.getFeatures(layer, context) for feature in features: writer.addFeature(feature, QgsFeatureSink.FastInsert) elif isinstance(out, OutputRaster): if out.compatible is not None: layer = QgsProcessingUtils.mapLayerFromString(out.compatible, context) format = self.getFormatShortNameFromFilename(out.value) orgFile = out.compatible destFile = out.value crsid = layer.crs().authid() settings = QgsSettings() path = str(settings.value('/GdalTools/gdalPath', '')) envval = str(os.getenv('PATH')) if not path.lower() in envval.lower().split(os.pathsep): envval += '%s%s' % (os.pathsep, path) os.putenv('PATH', envval) command = 'gdal_translate -of %s -a_srs %s %s %s' % (format, crsid, orgFile, destFile) if os.name == 'nt': command = command.split(" ") else: command = [command] proc = subprocess.Popen( command, shell=True, stdout=subprocess.PIPE, stdin=subprocess.PIPE, stderr=subprocess.STDOUT, universal_newlines=False, ) proc.communicate() elif isinstance(out, OutputTable): if out.compatible is not None: layer = QgsProcessingUtils.mapLayerFromString(out.compatible, context) writer = out.getTableWriter(layer.fields()) features = QgsProcessingUtils.getFeatures(layer, context) for feature in features: writer.addRecord(feature) feedback.setProgress(100 * i / float(len(self.outputs))) def getFormatShortNameFromFilename(self, filename): ext = filename[filename.rfind('.') + 1:] supported = GdalUtils.getSupportedRasters() for name in list(supported.keys()): exts = supported[name] if ext in exts: return name return 'GTiff' def resolveOutputs(self): """Sets temporary outputs (output.value = None) with a temporary file instead. Resolves expressions as well. """ try: for out in self.outputs: out.resolveValue(self) except ValueError as e: raise GeoAlgorithmExecutionException(str(e)) def setOutputCRS(self): context = dataobjects.createContext() layers = QgsProcessingUtils.compatibleLayers(QgsProject.instance()) for param in self.parameterDefinitions(): if isinstance(param, (ParameterRaster, ParameterVector, ParameterMultipleInput)): if param.value: if isinstance(param, ParameterMultipleInput): inputlayers = param.value.split(';') else: inputlayers = [param.value] for inputlayer in inputlayers: for layer in layers: if layer.source() == inputlayer: self.crs = layer.crs() return p = QgsProcessingUtils.mapLayerFromString(inputlayer, context) if p is not None: self.crs = p.crs() p = None return try: from qgis.utils import iface if iface is not None: self.crs = iface.mapCanvas().mapSettings().destinationCrs() except: pass def addOutput(self, output): # TODO: check that name does not exist if isinstance(output, Output): self.outputs.append(output) def addParameter(self, param): # TODO: check that name does not exist if isinstance(param, Parameter): self.parameters.append(param) def setOutputValue(self, outputName, value): for out in self.outputs: if out.name == outputName: out.setValue(value) def removeOutputFromName(self, name): for out in self.outputs: if out.name == name: self.outputs.remove(out) def getOutputFromName(self, name): for out in self.outputs: if out.name == name: return out def getParameterValue(self, name): for param in self.parameters: if param.name == name: return param.value return None def getOutputValue(self, name): for out in self.outputs: if out.name == name: return out.value return None def tr(self, string, context=''): if context == '': context = self.__class__.__name__ return QCoreApplication.translate(context, string) def trAlgorithm(self, string, context=''): if context == '': context = self.__class__.__name__ return string, QCoreApplication.translate(context, string) def executeAlgorithm(alg, parameters, context=None, feedback=None, model=None): """The method to use to call a processing algorithm. Although the body of the algorithm is in processAlgorithm(), it should be called using this method, since it performs some additional operations. Raises a GeoAlgorithmExecutionException in case anything goes wrong. :param parameters: """ if feedback is None: feedback = QgsProcessingFeedback() if context is None: context = dataobjects.createContext(feedback) #self.model = model #self.setOutputCRS() #self.resolveOutputs() #self.evaluateParameterValues() #self.runPreExecutionScript(feedback) result, ok = alg.run(parameters, context, feedback) #self.processAlgorithm(parameters, context, feedback) feedback.setProgress(100) return result, ok #self.convertUnsupportedFormats(context, feedback) #self.runPostExecutionScript(feedback)