#!/usr/bin/python -u # -*- coding: utf-8 -*- import cairo import cgi import Cookie import mapnik import os import pyotp import resource import shutil import signal import sys import tempfile # Limit maximum CPU time # The Postscript output format can sometimes take hours resource.setrlimit(resource.RLIMIT_CPU,(180,180)) # Limit memory usage # Some odd requests can cause extreme memory usage resource.setrlimit(resource.RLIMIT_AS,(4000000000, 4000000000)) # Routine to output HTTP headers def output_headers(content_type, filename = "", length = 0): print "Content-Type: %s" % content_type if filename: print "Content-Disposition: attachment; filename=\"%s\"" % filename if length: print "Content-Length: %d" % length print "" # Routine to output the contents of a file def output_file(file): file.seek(0) shutil.copyfileobj(file, sys.stdout) # Routine to get the size of a file def file_size(file): return os.fstat(file.fileno()).st_size # Routine to report an error def output_error(message, status = "400 Bad Request"): print "Status: %s" % status output_headers("text/html") print "" print "" print "Error" print "" print "" print "

Error

" print "

" % message print "" print "" # Create TOTP token validator totp = pyotp.TOTP('<%= @totp_key %>', interval = 3600) # Parse CGI parameters form = cgi.FieldStorage() # Import cookies cookies = Cookie.SimpleCookie(os.environ.get('HTTP_COOKIE')) # Make sure we have a user agent if not os.environ.has_key('HTTP_USER_AGENT'): os.environ['HTTP_USER_AGENT'] = 'NONE' # Make sure we have a referer if not os.environ.has_key('HTTP_REFERER'): os.environ['HTTP_REFERER'] = 'NONE' # Look for TOTP token if cookies.has_key('_osm_totp_token'): token = cookies['_osm_totp_token'].value else: token = None # Get the load average cputimes = [float(n) for n in open("/proc/stat").readline().rstrip().split()[1:-1]] idletime = cputimes[3] / sum(cputimes) # Process the request if not totp.verify(token, valid_window = 1): # Abort if the request didn't have a valid TOTP token output_error("Missing or invalid token") elif idletime < 0.2: # Abort if the CPU idle time on the machine is too low output_error("The server is too busy at the moment. Please wait a few minutes before trying again.", "503 Service Unavailable") <% @blocks["user_agents"].each do |user_agent| -%> elif os.environ['HTTP_USER_AGENT'] == '<%= user_agent %>': # Block scraper output_error("The server is too busy at the moment. Please wait a few minutes before trying again.", "503 Service Unavailable") <% end -%> <% @blocks["referers"].each do |referer| -%> elif os.environ['HTTP_REFERER'] == '<%= referer %>': # Block scraper output_error("The server is too busy at the moment. Please wait a few minutes before trying again.", "503 Service Unavailable") <% end -%> elif not form.has_key("bbox"): # No bounding box specified output_error("No bounding box specified") elif not form.has_key("scale"): # No scale specified output_error("No scale specified") elif not form.has_key("format"): # No format specified output_error("No format specified") else: # Create projection object prj = mapnik.Projection("+proj=merc +a=6378137 +b=6378137 +lat_ts=0.0 +lon_0=0.0 +x_0=0.0 +y_0=0 +k=1.0 +units=m +nadgrids=@null +no_defs +over"); # Get the bounds of the area to render bbox = [float(x) for x in form.getvalue("bbox").split(",")] if bbox[0] >= bbox[2] or bbox[1] >= bbox[3]: # Bogus bounding box output_error("Invalid bounding box") else: # Project the bounds to the map projection bbox = mapnik.forward_(mapnik.Box2d(*bbox), prj) # Get the style to use style = form.getvalue("style", "default") # Calculate the size of the final rendered image scale = float(form.getvalue("scale")) width = int(bbox.width() / scale / 0.00028) height = int(bbox.height() / scale / 0.00028) # Limit the size of map we are prepared to produce if width * height > 4000000: # Map is too large (limit is approximately A2 size) output_error("Map too large") else: # Create map map = mapnik.Map(width, height) # Load map configuration mapnik.load_map(map, "/srv/tile.openstreetmap.org/styles/%s/project.xml" % style) # Zoom the map to the bounding box map.zoom_to_box(bbox) # Fork so that we can handle crashes rendering the map pid = os.fork() # Render the map if pid == 0: if form.getvalue("format") == "png": image = mapnik.Image(map.width, map.height) mapnik.render(map, image) png = image.tostring("png") output_headers("image/png", "map.png", len(png)) sys.stdout.write(png) elif form.getvalue("format") == "jpeg": image = mapnik.Image(map.width, map.height) mapnik.render(map, image) jpeg = image.tostring("jpeg") output_headers("image/jpeg", "map.jpg", len(jpeg)) sys.stdout.write(jpeg) elif form.getvalue("format") == "svg": file = tempfile.NamedTemporaryFile(prefix = "export") surface = cairo.SVGSurface(file.name, map.width, map.height) surface.restrict_to_version(cairo.SVG_VERSION_1_2) mapnik.render(map, surface) surface.finish() output_headers("image/svg+xml", "map.svg", file_size(file)) output_file(file) elif form.getvalue("format") == "pdf": file = tempfile.NamedTemporaryFile(prefix = "export") surface = cairo.PDFSurface(file.name, map.width, map.height) mapnik.render(map, surface) surface.finish() output_headers("application/pdf", "map.pdf", file_size(file)) output_file(file) elif form.getvalue("format") == "ps": file = tempfile.NamedTemporaryFile(prefix = "export") surface = cairo.PSSurface(file.name, map.width, map.height) mapnik.render(map, surface) surface.finish() output_headers("application/postscript", "map.ps", file_size(file)) output_file(file) else: output_error("Unknown format '%s'" % form.getvalue("format")) else: pid, status = os.waitpid(pid, 0) if status & 0xff == signal.SIGXCPU: output_error("CPU time limit exceeded", "509 Resource Limit Exceeded") elif status & 0xff == signal.SIGSEGV: output_error("Memory limit exceeded", "509 Resource Limit Exceeded") elif status != 0: output_error("Internal server error", "500 Internal Server Error")