Grass engine refactoring, volume calculations using python

app/plugins/grass_engine.py

@@ -4,8 +4,6 @@ import tempfile
 import subprocess
 import os
 
-from string import Template
-
 from webodm import settings
 
 logger = logging.getLogger('app.logger')
@@ -30,12 +28,12 @@ class GrassEngine:
 
 
 class GrassContext:
-    def __init__(self, grass_binary, tmpdir = None, template_args = {}, location = None, auto_cleanup=True):
+    def __init__(self, grass_binary, tmpdir = None, script_opts = {}, location = None, auto_cleanup=True):
         self.grass_binary = grass_binary
         if tmpdir is None:
             tmpdir = os.path.basename(tempfile.mkdtemp('_grass_engine', dir=settings.MEDIA_TMP))
         self.tmpdir = tmpdir
-        self.template_args = template_args
+        self.script_opts = script_opts
         self.location = location
         self.auto_cleanup = auto_cleanup
 
@@ -48,15 +46,15 @@ class GrassContext:
         dst_path = os.path.abspath(os.path.join(self.get_cwd(), filename))
         with open(dst_path, 'w') as f:
             f.write(source)
-        self.template_args[param] = dst_path
+        self.script_opts[param] = dst_path
 
         if use_as_location:
-            self.set_location(self.template_args[param])
+            self.set_location(self.script_opts[param])
 
         return dst_path
 
     def add_param(self, param, value):
-        self.template_args[param] = value
+        self.script_opts[param] = value
 
     def set_location(self, location):
         """
@@ -75,25 +73,12 @@ class GrassContext:
 
         script = os.path.abspath(script)
 
-        # Create grass script via template substitution
-        try:
-            with open(script) as f:
-                script_content = f.read()
-        except FileNotFoundError:
-            raise GrassEngineException("Script does not exist: {}".format(script))
-
-        tmpl = Template(script_content)
-
-        # Write script to disk
-        if not os.path.exists(self.get_cwd()):
-            os.mkdir(self.get_cwd())
-
-        with open(os.path.join(self.get_cwd(), 'script.sh'), 'w') as f:
-            f.write(tmpl.substitute(self.template_args))
+        # Create param list
+        params = ["{}={}".format(opt,value) for opt,value in self.script_opts.items()]
 
         # Execute it
-        logger.info("Executing grass script from {}: {} -c {} location --exec sh script.sh".format(self.get_cwd(), self.grass_binary, self.location))
-        p = subprocess.Popen([self.grass_binary, '-c', self.location, 'location', '--exec', 'sh', 'script.sh'],
+        logger.info("Executing grass script from {}: {} -c {} location --exec python {} {}".format(self.get_cwd(), self.grass_binary, self.location, script, " ".join(params)))
+        p = subprocess.Popen([self.grass_binary, '-c', self.location, 'location', '--exec', 'python', script] + params,
                              cwd=self.get_cwd(), stdout=subprocess.PIPE, stderr=subprocess.PIPE)
         out, err = p.communicate()
 
@@ -108,14 +93,15 @@ class GrassContext:
     def serialize(self):
         return {
             'tmpdir': self.tmpdir,
-            'template_args': self.template_args,
+            'script_opts': self.script_opts,
             'location': self.location,
             'auto_cleanup': self.auto_cleanup
         }
 
     def cleanup(self):
-        if os.path.exists(self.get_cwd()):
-            shutil.rmtree(self.get_cwd())
+        pass
+        # if os.path.exists(self.get_cwd()):
+        #     shutil.rmtree(self.get_cwd())
 
     def __del__(self):
         if self.auto_cleanup:

plugins/measure/api.py

@@ -41,7 +41,7 @@ class TaskVolume(TaskView):
 
             celery_task_id = execute_grass_script.delay(os.path.join(
                 os.path.dirname(os.path.abspath(__file__)),
-                "calc_volume.grass"
+                "calc_volume.py"
             ), context.serialize()).task_id
 
             return Response({'celery_task_id': celery_task_id}, status=status.HTTP_200_OK)

plugins/measure/calc_volume.grass

@@ -1,32 +0,0 @@
-# area_file: Geospatial file containing the area to measure
-# points_file: Geospatial file containing the points defining the area
-# dsm_file: GeoTIFF DEM containing the surface
-# ------
-# output: prints the volume to stdout
-
-#Import raster and vector
-v.import input=${area_file} output=polygon_area --overwrite 
-v.import input=${points_file} output=polygon_points --overwrite
-v.buffer -s --overwrite input=polygon_area type=area output=region distance=1 minordistance=1
-r.external input=${dsm_file} output=dsm --overwrite
-
-# Set Grass region to vector bbox
-g.region vector=region
-
-# Create a mask to speed up computation
-r.mask vect=region
-
-# Transfer dsm raster data to vector
-v.what.rast map=polygon_points raster=dsm column=height
-
-# Decimate DSM and generate interpolation of new terrain
-v.surf.rst --overwrite input=polygon_points zcolumn=height elevation=dsm_below_pile
-
-# Compute difference between dsm and new dsm
-r.mapcalc expression='pile_height_above_dsm=dsm-dsm_below_pile' --overwrite
-
-# Set region to polygon area to calculate volume
-g.region vect=polygon_area
-
-# Volume output from difference
-r.volume -f input=pile_height_above_dsm

plugins/measure/calc_volume.py

@@ -0,0 +1,89 @@
+#%module
+#% description: Calculate volume of area and prints the volume to stdout
+#%end
+#%option
+#% key: area_file
+#% type: string
+#% required: yes
+#% multiple: no
+#% description: Geospatial file containing the area to measure
+#%end
+#%option
+#% key: points_file
+#% type: string
+#% required: yes
+#% multiple: no
+#% description: Geospatial file containing the points defining the area
+#%end
+#%option
+#% key: dsm_file
+#% type: string
+#% required: yes
+#% multiple: no
+#% description: GeoTIFF DEM containing the surface
+#%end
+
+import sys
+from grass.pygrass.modules import Module
+import grass.script as grass
+
+def main():
+    # Import raster and vector
+    Module("v.import", input=opts['area_file'], output="polygon_area", overwrite=True)
+    Module("v.import", input=opts['points_file'], output="polygon_points", overwrite=True)
+    Module("v.buffer", input="polygon_area", s=True, type="area", output="region", distance=1, minordistance=1, overwrite=True)
+    Module("r.external", input=opts['dsm_file'], output="dsm", overwrite=True)
+
+    # Set Grass region to vector bbox
+    Module("g.region", vector="region")
+
+    # Create a mask to speed up computation
+    Module("r.mask", vector="region")
+
+    # Transfer dsm raster data to vector
+    Module("v.what.rast", map="polygon_points", raster="dsm", column="height")
+
+    # Decimate DSM and generate interpolation of new terrain
+    Module("v.surf.rst", input="polygon_points", zcolumn="height", elevation="dsm_below_pile", overwrite=True)
+
+    # Compute difference between dsm and new dsm
+    Module("r.mapcalc", expression='pile_height_above_dsm=dsm-dsm_below_pile', overwrite=True)
+
+    # Set region to polygon area to calculate volume
+    Module("g.region", vector="polygon_area")
+
+    # Volume output from difference
+    Module("r.volume", input="pile_height_above_dsm", f=True)
+
+    return 0
+
+if __name__ == "__main__":
+    opts, _ = grass.parser()
+    sys.exit(main())
+
+#Import raster and vector
+# v.import input=${area_file} output=polygon_area --overwrite
+# v.import input=${points_file} output=polygon_points --overwrite
+# v.buffer -s --overwrite input=polygon_area type=area output=region distance=1 minordistance=1
+# r.external input=${dsm_file} output=dsm --overwrite
+#
+# # Set Grass region to vector bbox
+# g.region vector=region
+#
+# # Create a mask to speed up computation
+# r.mask vect=region
+#
+# # Transfer dsm raster data to vector
+# v.what.rast map=polygon_points raster=dsm column=height
+#
+# # Decimate DSM and generate interpolation of new terrain
+# v.surf.rst --overwrite input=polygon_points zcolumn=height elevation=dsm_below_pile
+#
+# # Compute difference between dsm and new dsm
+# r.mapcalc expression='pile_height_above_dsm=dsm-dsm_below_pile' --overwrite
+#
+# # Set region to polygon area to calculate volume
+# g.region vect=polygon_area
+#
+# # Volume output from difference
+# r.volume -f input=pile_height_above_dsm