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flightgear/scripts/python/terrasync.py
Torsten Dreyer e2afbb4678 terrasync.py: cleanup and add some more power
- add option --quick
  check sha1sum of .dirindex files and skip directory if hash matches
- add option --remove-orphan
  remove orphan files (files exist locally but not on server)
- be less verbose
- write .dirindex files locally
2016-05-11 23:04:24 +02:00

202 lines
6.2 KiB
Python
Executable file

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
#
# Copyright (C) 2016 Torsten Dreyer
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License as
# published by the Free Software Foundation; either version 2 of the
# License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
#
# terrasync.py - synchronize terrascenery data to your local disk
# needs dnspython (pip install dnspython)
#
import os
import hashlib
import urllib.request
from os import listdir
from os.path import isfile, join
dirindex = ".dirindex"
DIRINDEXVERSION = 1
URL="http://flightgear.sourceforge.net/scenery"
# User master repository for now
#URL="automatic"
TARGET="."
QUICK=False
REMOVE_ORPHAN=False
########################################################################
def fn_hash_of_file(fname):
if not os.path.exists( fname ):
return None
hash = hashlib.sha1()
try:
with open(fname, "rb") as f:
for chunk in iter(lambda: f.read(4096), b""):
hash.update(chunk)
except:
pass
return hash.hexdigest()
########################################################################
def do_download_file( _url, _path, _localfile, _hash, _force ):
if os.path.exists( _localfile ) and not _force:
h = fn_hash_of_file(_localfile)
if h == _hash:
#print("hash match for ", _localfile)
return False
r = urllib.request.urlopen( _url + _path )
with open(_localfile, 'wb') as f:
f.write( r.read() )
#print("downloaded ", _localfile, " from ", _url + _path )
return True
########################################################################
def do_terrasync( _url, _path, _localdir, _dirIndexHash ):
url = _url + _path
print(url)
if not os.path.exists( _localdir ):
os.makedirs( _localdir )
# download and process .dirindex as temporary file
# rename to .dirindex after successful processing of directory
# in case of abort, .dirindex.tmp will be removed as orphan
myDirIndexFile = os.path.join(_localdir, ".dirindex.tmp")
try:
if not do_download_file( url, "/.dirindex", myDirIndexFile, _dirIndexHash, QUICK == False ):
# dirindex hash matches, file not downloaded, skip directory
return
except urllib.error.HTTPError as err:
if err.code == 404 and _path == "":
# HACK: only the master on SF provides .dirindex for root, fake it if it's missing
print("Using static root hack.")
for _sub in ("Models", "Terrain", "Objects", "Airports" ):
do_terrasync( _url, "/" + _sub, os.path.join(_localdir,_sub), None )
return
else:
raise
with open(myDirIndexFile, 'r') as myDirIndex:
serverFiles = []
for line in myDirIndex:
tokens = line.rstrip().split(':')
if( len(tokens) == 0 ):
continue
# TODO: check version number, should be equal to DIRINDEXVERSION
# otherwise complain and terminate
if( tokens[0] == "version" ):
continue
if( tokens[0] == "path" ):
continue
if( tokens[0] == "d" ):
do_terrasync( url, "/" + tokens[1], os.path.join(_localdir,tokens[1]), tokens[2] )
if( tokens[0] == "f" ):
do_download_file( url, "/" + tokens[1], os.path.join(_localdir,tokens[1]), tokens[2], False )
serverFiles.append( tokens[1] )
os.rename( myDirIndexFile, os.path.join(_localdir, ".dirindex" ) )
localFiles = [f for f in listdir(_localdir) if isfile(join(_localdir, f))]
for f in localFiles:
if f != ".dirindex" and not f in serverFiles:
if REMOVE_ORPHAN:
os.remove( os.path.join(_localdir,f) )
#TODO: cleanup orphan files
########################################################################
import getopt, sys, random, re
try:
opts, args = getopt.getopt(sys.argv[1:], "u:t:qr", [ "url=", "target=", "quick", "remove-orphan" ])
except getopt.GetoptError:
print("terrasync.py [--url=http://some.server.org/scenery] [--target=/some/path] [-q|--quick] [-r|--remove-orphan]")
sys.exit(2)
for opt, arg in opts:
if opt in( "-u", "--url"):
URL = arg
elif opt in ( "-t", "--target"):
TARGET= arg
elif opt in ("-q", "--quick"):
QUICK = True
elif opt in ("-r", "--remove-orphan"):
REMOVE_ORPHAN = True
# automatic URL lookup from DNS NAPTR
# - lookup terrasync.flightgear.org, type=NAPTR, service="ws20", flags="U"
# - sort by order,preference ascending
# - pick entries with lowest order and preference
# - randomly pick one of those
# - use regexp fields URL
if URL == "automatic":
import dns.resolver
dnsResolver = dns.resolver.Resolver()
order = -1
preference = -1
# find lowes preference/order for service 'ws20' and flags 'U'
dnsAnswer = dnsResolver.query("terrasync.flightgear.org", "NAPTR" )
for naptr in dnsAnswer:
if naptr.service != b'ws20' or naptr.flags != b'U':
continue
if order == -1 or naptr.order < order:
order = naptr.order
preference = naptr.preference
if order == naptr.order:
if naptr.preference < preference:
preference = naptr.preference
# grab candidats
candidates = []
for naptr in dnsAnswer:
if naptr.service != b'ws20' or naptr.flags != b'U' or naptr.preference != preference or naptr.order != order:
continue
candidates.append( naptr.regexp.decode('utf-8') )
if not candidates:
print("sorry, no terrascenery URLs found. You may specify one with --url=http://some.url.org/foo")
sys.exit(3)
_url = random.choice(candidates)
_subst = _url.split(_url[0]) # split string, first character is separator <sep>regex<sep>replacement<sep>
URL = re.sub(_subst[1], _subst[2], "" ) # apply regex substitude on empty string
print( "terrasyncing from ", URL, "to ", TARGET )
do_terrasync( URL, "", TARGET, None )
########################################################################