--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/tools/stream.py	Thu Feb 08 00:37:42 2018 +0100
@@ -0,0 +1,200 @@
+#!/usr/bin/env python2
+# -*- coding: utf-8 -*-
+
+# SAT: a jabber client
+# Copyright (C) 2009-2018 Jérôme Poisson (goffi@goffi.org)
+
+# This program is free software: you can redistribute it and/or modify
+# it under the terms of the GNU Affero General Public License as published by
+# the Free Software Foundation, either version 3 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 Affero General Public License for more details.
+
+# You should have received a copy of the GNU Affero General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+""" interfaces """
+
+from sat.core import exceptions
+from sat.core.constants import Const as C
+from sat.core.log import getLogger
+from twisted.protocols import basic
+from twisted.internet import interfaces
+from zope import interface
+import uuid
+import os
+
+log = getLogger(__name__)
+
+
+class IStreamProducer(interface.Interface):
+
+    def startStream(consumer):
+        """start producing the stream
+
+        @return (D): deferred fired when stream is finished
+        """
+
+
+class SatFile(object):
+    """A file-like object to have high level files manipulation"""
+    # TODO: manage "with" statement
+
+    def __init__(self, host, client, path, mode='rb', uid=None, size=None, data_cb=None, auto_end_signals=True):
+        """
+        @param host: %(doc_host)s
+        @param path(str): path of the file to get
+        @param mode(str): same as for built-in "open" function
+        @param uid(unicode, None): unique id identifing this progressing element
+            This uid will be used with self.host.progressGet
+            will be automaticaly generated if None
+        @param size(None, int): size of the file (when known in advance)
+        @param data_cb(None, callable): method to call on each data read/write
+            mainly useful to do things like calculating hash
+        @param auto_end_signals(bool): if True, progressFinished and progressError signals are automatically sent
+            if False, you'll have to call self.progressFinished and self.progressError yourself
+            progressStarted signal is always sent automatically
+        """
+        self.host = host
+        self.profile = client.profile
+        self.uid = uid or unicode(uuid.uuid4())
+        self._file = open(path, mode)
+        self.size = size
+        self.data_cb = data_cb
+        self.auto_end_signals = auto_end_signals
+        metadata = self.getProgressMetadata()
+        self.host.registerProgressCb(self.uid, self.getProgress, metadata, profile=client.profile)
+        self.host.bridge.progressStarted(self.uid, metadata, client.profile)
+
+    def checkSize(self):
+        """Check that current size correspond to given size
+
+        must be used when the transfer is supposed to be finished
+        @return (bool): True if the position is the same as given size
+        @raise exceptions.NotFound: size has not be specified
+        """
+        position = self._file.tell()
+        if self.size is None:
+            raise exceptions.NotFound
+        return position == self.size
+
+    def close(self, progress_metadata=None, error=None):
+        """Close the current file
+
+        @param progress_metadata(None, dict): metadata to send with _onProgressFinished message
+        @param error(None, unicode): set to an error message if progress was not successful
+            mutually exclusive with progress_metadata
+            error can happen even if error is None, if current size differ from given size
+        """
+        if self._file.closed:
+            return # avoid double close (which is allowed) error
+        if error is None:
+            try:
+                size_ok = self.checkSize()
+            except exceptions.NotFound:
+                size_ok = True
+            if not size_ok:
+                error = u'declared and actual size mismatch'
+                log.warning(error)
+                progress_metadata = None
+
+        self._file.close()
+
+        if self.auto_end_signals:
+            if error is None:
+                self.progressFinished(progress_metadata)
+            else:
+                assert progress_metadata is None
+                self.progressError(error)
+
+        self.host.removeProgressCb(self.uid, self.profile)
+
+    def progressFinished(self, metadata=None):
+        if metadata is None:
+            metadata = {}
+        self.host.bridge.progressFinished(self.uid, metadata, self.profile)
+
+    def progressError(self, error):
+        self.host.bridge.progressError(self.uid, error, self.profile)
+
+    def flush(self):
+        self._file.flush()
+
+    def write(self, buf):
+        self._file.write(buf)
+        if self.data_cb is not None:
+            return self.data_cb(buf)
+
+    def read(self, size=-1):
+        read = self._file.read(size)
+        if self.data_cb is not None and read:
+            self.data_cb(read)
+        return read
+
+    def seek(self, offset, whence=os.SEEK_SET):
+        self._file.seek(offset, whence)
+
+    def tell(self):
+        return self._file.tell()
+
+    def mode(self):
+        return self._file.mode()
+
+    def getProgressMetadata(self):
+        """Return progression metadata as given to progressStarted
+
+        @return (dict): metadata (check bridge for documentation)
+        """
+        metadata = {'type': C.META_TYPE_FILE}
+
+        mode = self._file.mode
+        if '+' in mode:
+            pass # we have no direction in read/write modes
+        elif mode in ('r', 'rb'):
+            metadata['direction'] = 'out'
+        elif mode in ('w', 'wb'):
+            metadata['direction'] = 'in'
+        elif 'U' in mode:
+            metadata['direction'] = 'out'
+        else:
+            raise exceptions.InternalError
+
+        metadata['name'] = self._file.name
+
+        return metadata
+
+    def getProgress(self, progress_id, profile):
+        ret = {'position': self._file.tell()}
+        if self.size:
+            ret['size'] = self.size
+        return ret
+
+
+@interface.implementer(IStreamProducer)
+@interface.implementer(interfaces.IConsumer)
+class FileStreamObject(basic.FileSender):
+
+    def __init__(self, host, client, path, **kwargs):
+        """
+
+        A SatFile will be created and put in self.file_obj
+        @param path(unicode): path to the file
+        @param **kwargs: kw arguments to pass to SatFile
+        """
+        self.file_obj = SatFile(host, client, path, **kwargs)
+
+    def registerProducer(self, producer, streaming):
+        pass
+
+    def startStream(self, consumer):
+        return self.beginFileTransfer(self.file_obj, consumer)
+
+    def write(self, data):
+        self.file_obj.write(data)
+
+    def close(self, *args, **kwargs):
+        self.file_obj.close(*args, **kwargs)