181 lines
6.9 KiB
Python
181 lines
6.9 KiB
Python
import base64
|
|
import logging
|
|
import os
|
|
import re
|
|
import threading
|
|
import time
|
|
from io import BytesIO
|
|
|
|
import pylibmc
|
|
import requests
|
|
|
|
from c3nav.mapdata.utils.cache import CachePackage
|
|
from c3nav.mapdata.utils.tiles import (build_access_cache_key, build_base_cache_key, build_tile_etag, get_tile_bounds,
|
|
parse_tile_access_cookie)
|
|
|
|
logging.basicConfig(level=logging.DEBUG if os.environ.get('C3NAV_DEBUG') else logging.INFO,
|
|
format='[%(asctime)s] [%(process)s] [%(levelname)s] %(name)s: %(message)s',
|
|
datefmt='%Y-%m-%d %H:%M:%S %z')
|
|
logger = logging.getLogger('c3nav')
|
|
|
|
|
|
class TileServer:
|
|
def __init__(self):
|
|
self.path_regex = re.compile(r'^/(\d+)/(\d+)/(-?\d+)/(-?\d+).png$')
|
|
|
|
try:
|
|
self.instance_name = os.environ['C3NAV_INSTANCE_NAME']
|
|
except KeyError:
|
|
raise Exception('C3NAV_INSTANCE_NAME needs to be set.')
|
|
|
|
self.cookie_regex = re.compile(r'(^| )c3nav_'+re.escape(self.instance_name)+r'_tile_access="?([^;" ]+)"?')
|
|
|
|
try:
|
|
self.upstream_base = os.environ['C3NAV_UPSTREAM_BASE'].strip('/')
|
|
except KeyError:
|
|
raise Exception('C3NAV_UPSTREAM_BASE needs to be set.')
|
|
|
|
self.tile_secret = os.environ.get('C3NAV_TILE_SECRET', None)
|
|
if not self.tile_secret:
|
|
tile_secret_file = None
|
|
try:
|
|
tile_secret_file = os.environ['C3NAV_TILE_SECRET_FILE']
|
|
self.tile_secret = open(tile_secret_file).read().strip()
|
|
except KeyError:
|
|
raise Exception('C3NAV_TILE_SECRET or C3NAV_TILE_SECRET_FILE need to be set.')
|
|
except FileNotFoundError:
|
|
raise Exception('The C3NAV_TILE_SECRET_FILE (%s) does not exist.' % tile_secret_file)
|
|
|
|
self.auth_headers = {'X-Tile-Secret': base64.b64encode(self.tile_secret.encode())}
|
|
|
|
self.cache_package = None
|
|
self.cache_package_etag = None
|
|
|
|
self.tile_cache = pylibmc.Client(["127.0.0.1"], binary=True, behaviors={"tcp_nodelay": True, "ketama": True})
|
|
|
|
wait = 1
|
|
while True:
|
|
success = self.load_cache_package()
|
|
if success:
|
|
logger.info('Cache package successfully loaded.')
|
|
break
|
|
logger.info('Retrying after %s seconds...' % wait)
|
|
time.sleep(wait)
|
|
wait = min(10, wait*2)
|
|
|
|
threading.Thread(target=self.update_cache_package_thread, daemon=True).start()
|
|
|
|
def update_cache_package_thread(self):
|
|
while True:
|
|
time.sleep(60)
|
|
self.load_cache_package()
|
|
|
|
def load_cache_package(self):
|
|
logger.debug('Downloading cache package from upstream...')
|
|
try:
|
|
headers = self.auth_headers.copy()
|
|
if self.cache_package_etag is not None:
|
|
headers['If-None-Match'] = self.cache_package_etag
|
|
r = requests.get(self.upstream_base+'/map/cache/package.tar.xz', headers=headers)
|
|
|
|
if r.status_code == 403:
|
|
logger.error('Rejected cache package download with Error 403. Tile secret is probably incorrect.')
|
|
return False
|
|
|
|
if r.status_code == 304:
|
|
if self.cache_package is not None:
|
|
logger.debug('Not modified.')
|
|
return True
|
|
logger.error('Unexpected not modified.')
|
|
return False
|
|
|
|
r.raise_for_status()
|
|
except Exception as e:
|
|
logger.error('Cache package download failed: %s' % e)
|
|
return False
|
|
|
|
try:
|
|
self.cache_package = CachePackage.read(BytesIO(r.content))
|
|
self.cache_package_etag = r.headers.get('ETag', None)
|
|
except Exception as e:
|
|
logger.error('Cache package parsing failed: %s' % e)
|
|
return False
|
|
return True
|
|
|
|
def not_found(self, start_response, text):
|
|
start_response('404 Not Found', [('Content-Type', 'text/plain')])
|
|
return [text]
|
|
|
|
def deliver_tile(self, start_response, etag, data):
|
|
start_response('200 OK', [('Content-Type', 'image/png'),
|
|
('Cache-Control', 'no-cache'),
|
|
('ETag', etag)])
|
|
return [data]
|
|
|
|
def __call__(self, env, start_response):
|
|
match = self.path_regex.match(env['PATH_INFO'])
|
|
if match is None:
|
|
return self.not_found(start_response, b'invalid tile path.')
|
|
|
|
level, zoom, x, y = match.groups()
|
|
|
|
zoom = int(zoom)
|
|
if not (0 <= zoom <= 10):
|
|
return self.not_found(start_response, b'zoom out of bounds.')
|
|
|
|
# do this to be thread safe
|
|
cache_package = self.cache_package
|
|
|
|
# check if bounds are valid
|
|
x = int(x)
|
|
y = int(y)
|
|
minx, miny, maxx, maxy = get_tile_bounds(zoom, x, y)
|
|
if not cache_package.bounds_valid(minx, miny, maxx, maxy):
|
|
return self.not_found(start_response, b'coordinates out of bounds.')
|
|
|
|
# get level
|
|
level = int(level)
|
|
level_data = cache_package.levels.get(level)
|
|
if level_data is None:
|
|
return self.not_found(start_response, b'invalid level.')
|
|
|
|
# decode access permissions
|
|
cookie = env.get('HTTP_COOKIE', None)
|
|
if cookie:
|
|
cookie = self.cookie_regex.search(cookie)
|
|
if cookie:
|
|
cookie = cookie.group(2)
|
|
access_permissions = parse_tile_access_cookie(cookie, self.tile_secret) if cookie else set()
|
|
|
|
# only access permissions that are affecting this tile
|
|
access_permissions &= set(level_data.restrictions[minx:miny, maxx:maxy])
|
|
|
|
# build cache keys
|
|
last_update = level_data.history.last_update(minx, miny, maxx, maxy)
|
|
base_cache_key = build_base_cache_key(last_update)
|
|
access_cache_key = build_access_cache_key(access_permissions)
|
|
|
|
# check browser cache
|
|
if_none_match = env.get('HTTP_IF_NONE_MATCH')
|
|
tile_etag = build_tile_etag(level, zoom, x, y, base_cache_key, access_cache_key, self.tile_secret)
|
|
if if_none_match == tile_etag:
|
|
start_response('304 Not Modified', [('Content-Type', 'text/plain'),
|
|
('ETag', tile_etag)])
|
|
return [b'']
|
|
|
|
cached_result = self.tile_cache.get(tile_etag)
|
|
if cached_result is not None:
|
|
return self.deliver_tile(start_response, tile_etag, cached_result)
|
|
|
|
r = requests.get('%s/map/%d/%d/%d/%d/%s.png' % (self.upstream_base, level, zoom, x, y, access_cache_key),
|
|
headers=self.auth_headers)
|
|
|
|
if r.status_code == 200 and r.headers['Content-Type'] == 'image/png':
|
|
self.tile_cache[tile_etag] = r.content
|
|
return self.deliver_tile(start_response, tile_etag, r.content)
|
|
|
|
start_response('%d %s' % (r.status_code, r.reason), [('Content-Type', r.headers['Content-Type'])])
|
|
return [r.content]
|
|
|
|
|
|
application = TileServer()
|