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comparison sat/plugins/plugin_misc_download.py @ 3088:d1464548055a

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plugin file download: meta plugin to handle file download: - first code in backend to use async/await Python syntax \o/ - plugin with file upload - URL schemes can be registered - `http` and `https` schemes are handled by default
author Goffi <goffi@goffi.org>
date Fri, 20 Dec 2019 12:28:04 +0100
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children 9d0df638c8b4
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3087:a51f7fce1e2c 3088:d1464548055a
1 #!/usr/bin/env python3
2
3 # SAT plugin for downloading files
4 # Copyright (C) 2009-2019 Jérôme Poisson (goffi@goffi.org)
5
6 # This program is free software: you can redistribute it and/or modify
7 # it under the terms of the GNU Affero General Public License as published by
8 # the Free Software Foundation, either version 3 of the License, or
9 # (at your option) any later version.
10
11 # This program is distributed in the hope that it will be useful,
12 # but WITHOUT ANY WARRANTY; without even the implied warranty of
13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 # GNU Affero General Public License for more details.
15
16 # You should have received a copy of the GNU Affero General Public License
17 # along with this program. If not, see <http://www.gnu.org/licenses/>.
18
19 from pathlib import Path
20 from urllib.parse import urlparse
21 import treq
22 from twisted.internet import defer
23 from twisted.words.protocols.jabber import error as jabber_error
24 from sat.core.i18n import _, D_
25 from sat.core.constants import Const as C
26 from sat.core.log import getLogger
27 from sat.core import exceptions
28 from sat.tools import xml_tools
29 from sat.tools.common import data_format
30 from sat.tools import stream
31
32 log = getLogger(__name__)
33
34
35 PLUGIN_INFO = {
36 C.PI_NAME: "File Download",
37 C.PI_IMPORT_NAME: "DOWNLOAD",
38 C.PI_TYPE: C.PLUG_TYPE_MISC,
39 C.PI_MAIN: "DownloadPlugin",
40 C.PI_HANDLER: "no",
41 C.PI_DESCRIPTION: _("""File download management"""),
42 }
43
44
45 class DownloadPlugin(object):
46
47 def __init__(self, host):
48 log.info(_("plugin Download initialization"))
49 self.host = host
50 host.bridge.addMethod(
51 "fileDownload",
52 ".plugin",
53 in_sign="ssss",
54 out_sign="a{ss}",
55 method=self._fileDownload,
56 async_=True,
57 )
58 host.bridge.addMethod(
59 "fileDownloadComplete",
60 ".plugin",
61 in_sign="ssss",
62 out_sign="s",
63 method=self._fileDownloadComplete,
64 async_=True,
65 )
66 self._download_callbacks = {}
67 self.registerScheme('http', self.downloadHTTP)
68 self.registerScheme('https', self.downloadHTTP)
69
70 def _fileDownload(self, uri, dest_path, options_s, profile):
71 client = self.host.getClient(profile)
72 options = data_format.deserialise(options_s)
73
74 return defer.ensureDeferred(self.fileDownload(
75 client, uri, Path(dest_path), options
76 ))
77
78 async def fileDownload(self, client, uri, dest_path, options=None):
79 """Send a file using best available method
80
81 parameters are the same as for [download]
82 @return (dict): action dictionary, with progress id in case of success, else xmlui
83 message
84 """
85 try:
86 progress_id, __ = await self.download(client, uri, dest_path, options)
87 except Exception as e:
88 if (isinstance(e, jabber_error.StanzaError)
89 and e.condition == 'not-acceptable'):
90 reason = e.text
91 else:
92 reason = str(e)
93 msg = D_("Can't download file: {reason}").format(reason=reason)
94 log.warning(msg)
95 return {
96 "xmlui": xml_tools.note(
97 msg, D_("Can't download file"), C.XMLUI_DATA_LVL_WARNING
98 ).toXml()
99 }
100 else:
101 return {"progress": progress_id}
102
103 def _fileDownloadComplete(self, uri, dest_path, options_s, profile):
104 client = self.host.getClient(profile)
105 options = data_format.deserialise(options_s)
106
107 d = defer.ensureDeferred(self.fileDownloadComplete(
108 client, uri, Path(dest_path), options
109 ))
110 d.addCallback(lambda path: str(path))
111 return d
112
113 async def fileDownloadComplete(self, client, uri, dest_path, options=None):
114 """Helper method to fully download a file and return its path
115
116 parameters are the same as for [download]
117 @return (str): path to the downloaded file
118 """
119 __, download_d = await self.download(client, uri, dest_path, options)
120 await download_d
121 return dest_path
122
123 async def download(self, client, uri, dest_path, options=None):
124 """Send a file using best available method
125
126 @param uri(str): URI to the file to download
127 @param dest_path(str, Path): where the file must be downloaded
128 @param options(dict, None): options depending on scheme handler
129 Some common options:
130 - ignore_tls_errors(bool): True to ignore SSL/TLS certificate verification
131 used only if HTTPS transport is needed
132 @return (tuple[unicode,D(unicode)]): progress_id and a Deferred which fire
133 download URL when download is finished
134 """
135 if options is None:
136 options = {}
137
138 dest_path = Path(dest_path)
139 uri_parsed = urlparse(uri, 'http')
140 try:
141 callback = self._download_callbacks[uri_parsed.scheme]
142 except KeyError:
143 raise exceptions.NotFound(f"Can't find any handler for uri {uri}")
144 else:
145 return await callback(client, uri_parsed, dest_path, options)
146
147 def registerScheme(self, scheme, download_cb):
148 """Register an URI scheme handler
149
150 @param scheme(unicode): URI scheme this callback is handling
151 @param download_cb(callable): callback to download a file
152 arguments are:
153 - (SatXMPPClient) client
154 - (urllib.parse.SplitResult) parsed URI
155 - (Path) destination path where the file must be downloaded
156 - (dict) options
157 must return a tuple with progress_id and a Deferred which fire when download
158 is finished
159 """
160 if scheme in self._download_callbacks:
161 raise exceptions.ConflictError(
162 f"A method with scheme {scheme!r} is already registered"
163 )
164 self._download_callbacks[scheme] = download_cb
165
166 def unregister(self, scheme):
167 try:
168 del self._download_callbacks[scheme]
169 except KeyError:
170 raise exceptions.NotFound(f"No callback registered for scheme {scheme!r}")
171
172 async def downloadHTTP(self, client, uri_parsed, dest_path, options):
173 url = uri_parsed.geturl()
174
175 head_data = await treq.head(url)
176 try:
177 content_length = int(head_data.headers.getRawHeaders('content-length')[0])
178 except (KeyError, TypeError, IndexError):
179 content_length = None
180 log.debug(f"No content lenght found at {url}")
181 file_obj = stream.SatFile(
182 self.host,
183 client,
184 dest_path,
185 mode="wb",
186 size = content_length,
187 )
188
189 progress_id = file_obj.uid
190
191 resp = await treq.get(url, unbuffered=True)
192 d = treq.collect(resp, file_obj.write)
193 d.addBoth(lambda _: file_obj.close())
194 return progress_id, d