Using Mapscript to create a mapfile from scratch

Question

Following a few online tutorials I have seen, I am trying to create a mapfile from scratch using mapscript. However, when I try to create the layer object, I get an error in the init of mapscript.py; NameError: global name 'args' is not defined.

Does anyone see something obvious? When I use a mapfile that already exists on disk, everything works as expected.

 # create a new mapfile from scratch
 self.map = mapscript.mapObj()
 self.map.save('temp.map')
 self.map.setSize(256,256)
 self.map.setExtent(-180.0,-90.0,180.0,90.0)
 self.map.units= mapscript.MS_DD
 self.map.imagecolor.setRGB(255,255,255)
 # create a layer for the raster
 self.layer = mapscript.layerObj(self.map) ----> ERROR HAPPENS HERE
 self.layer.name= 'tilesource'
 self.layer.type= mapscript.MS_RASTER
 self.layer.status = mapscript.MS_ON
 self.layer.data= rasterpath

• alxx: Was this resolved somehow? I'm getting the same error.

Answer 1

According to http://mapserver.org/mapscript/mapfile.html, creating a layer object works differently:

test_map = new mapscript.mapObj()
new_layer = new mapscript.layerObj()
li = test_map.insertLayer(new_layer)

• user890: Thanks for the suggestion, still get the same error with this approach.
• underdark: Can you post the whole script? I can't see where it gets "global name 'args'" from.
• user890: The error is happening in mapscript.py, the SWIG generated wrapper. Its occurring in the init function at Line 1264. Do you want me to attach the mapscript.py file?
• underdark: So "new mapscript.layerObj()" produces the same error like "mapscript.layerObj(self.map)"? (Notice keyword "new".) Which version of Mapserver are you running?
• geographika: The new keyword isn't required for Python. These seem to be left over from the PHP examples.

Answer 2

I am a mapserver developer and I have just committed a patch that should solve this issue. See changeset r12309 for the details.

Answer 3

I've been having the same problem when trying to create a new CLASS object. I've logged it as a bug as the SWIG wrappers seem incorrect for both layerObj and classObj. The args variable is defined in neither:

def __init__(self, map = None): 
 this = _mapscript.new_layerObj(map)
 try: self.this.append(this)
 except: self.this = this
 if 1:
 if args and len(args)!=0:
 self.p_map=args[0]
 else:
 self.p_map=None

http://trac.osgeo.org/mapserver/ticket/3940

Using MapServer 6.0 and Python SWIG bindings version 1.3.39