def read(self, layer, coord, format):
body = Disk.read(self, layer, coord, format)
self.signal_land_or_sea(body, layer, coord, format)
# we should never get here
return body
def read(self, layer, coord, format):
""" Read a cached tile.
"""
fullpath = self._fullpath(layer, coord, format)
if not exists(fullpath):
return None
if os.stat(fullpath).st_size == self.empty_size:
raise TheTileLeftANote(status_code=404, emit_content_type=False)
return Disk.read(self, layer, coord, format)
def signal_land_or_sea(self, body, layer, coord, format):
if body:
md5sum = self.md5sum(body)
second_md5sum = self.md5sum(Disk.read(self, self.second, coord, format))
headers = Headers([('Access-Control-Expose-Headers', 'X-Land-Or-Sea')])
headers.setdefault('X-Land-Or-Sea', '0')
if second_md5sum and md5sum == second_md5sum:
if md5sum == self.land_md5:
headers['X-Land-Or-Sea'] = '1'
elif md5sum == self.sea_md5:
headers['X-Land-Or-Sea'] = '2'
raise TheTileLeftANote(content=body, headers=headers)
