1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
|
# Licensed to the Apache Software Foundation (ASF) under one or more
# contributor license agreements. See the NOTICE file distributed with
# this work for additional information regarding copyright ownership.
# The ASF licenses this file to You under the Apache License, Version 2.0
# (the "License"); you may not use this file except in compliance with
# the License. You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import os
from urlparse import urljoin
from ...extension import parser
from ...utils.collections import StrictList
from ...utils.uris import as_file
from .loader import Loader
from .file import FileTextLoader
from .request import RequestTextLoader
from .exceptions import DocumentNotFoundException
class UriTextLoader(Loader):
"""
Base class for ARIA URI loaders.
See :class:`~aria.parser.loading.UriLocation`.
Supports a list of search prefixes that are tried in order if the URI cannot be found.
They will be:
* If ``origin_location`` is provided its prefix will come first.
* Then the prefixes in the :class:`LoadingContext` will be added.
* Finally, the parser can supply a ``uri_loader_prefix`` function with extra prefixes.
"""
def __init__(self, context, location, origin_location=None):
self.context = context
self.location = location
self._prefixes = StrictList(value_class=basestring)
self._loader = None
def add_prefix(prefix):
if prefix and (prefix not in self._prefixes):
self._prefixes.append(prefix)
def add_prefixes(prefixes):
for prefix in prefixes:
add_prefix(prefix)
if origin_location is not None:
add_prefix(origin_location.prefix)
add_prefixes(context.prefixes)
add_prefixes(parser.uri_loader_prefix())
def open(self):
try:
self._open(self.location.uri)
return
except DocumentNotFoundException:
# Try prefixes in order
for prefix in self._prefixes:
prefix_as_file = as_file(prefix)
if prefix_as_file is not None:
uri = os.path.join(prefix_as_file, self.location.uri)
else:
uri = urljoin(prefix, self.location.uri)
try:
self._open(uri)
return
except DocumentNotFoundException:
pass
raise DocumentNotFoundException('document not found at URI: "%s"' % self.location)
def close(self):
if self._loader is not None:
self._loader.close()
def load(self):
return self._loader.load() if self._loader is not None else None
def _open(self, uri):
the_file = as_file(uri)
if the_file is not None:
uri = the_file
loader = FileTextLoader(self.context, uri)
else:
loader = RequestTextLoader(self.context, uri)
loader.open() # might raise an exception
self._loader = loader
self.location.uri = uri
|
