From: Benoît Pin Date: Mon, 25 Oct 2010 13:00:45 +0000 (+0200) Subject: Reprise du code pour support des blobs. X-Git-Url: https://scm.cri.mines-paristech.fr/git/Photo.git/commitdiff_plain/2ad7c649b30366754569fbdbb92504fcb0bab1bf?ds=inline;hp=8bd9c946d25f740df11c44a67621b1220b6f7696 Reprise du code pour support des blobs. --- diff --git a/blobbases.py b/blobbases.py index 0da0f8b..c0084c3 100755 --- a/blobbases.py +++ b/blobbases.py @@ -52,6 +52,11 @@ from zope.event import notify from zope.lifecycleevent import ObjectModifiedEvent from zope.lifecycleevent import ObjectCreatedEvent +from ZODB.blob import Blob + +CHUNK_SIZE = 1 << 16 + + manage_addFileForm = DTMLFile('dtml/imageAdd', globals(), Kind='File', @@ -71,19 +76,9 @@ def manage_addFile(self, id, file='', title='', precondition='', id, title = cookId(id, title, file) self=self.this() + self._setObject(id, File(id,title,file,content_type, precondition)) - # First, we create the file without data: - self._setObject(id, File(id,title,'',content_type, precondition)) - newFile = self._getOb(id) - - # Now we "upload" the data. By doing this in two steps, we - # can use a database trick to make the upload more efficient. - if file: - newFile.manage_upload(file) - if content_type: - newFile.content_type=content_type - notify(ObjectCreatedEvent(newFile)) if REQUEST is not None: @@ -103,7 +98,7 @@ class File(Persistent, Implicit, PropertyManager, IWriteLock, HTTPRangeSupport.HTTPRangeInterface, ) - meta_type='File' + meta_type='Blob File' security = ClassSecurityInfo() security.declareObjectProtected(View) @@ -141,10 +136,62 @@ class File(Persistent, Implicit, PropertyManager, self.__name__=id self.title=title self.precondition=precondition - - data, size = self._read_data(file) - content_type=self._get_content_type(file, data, id, content_type) - self.update_data(data, content_type, size) + self.uploaded_filename = cookId('', '', file)[0] + self.bdata = Blob() + + content_type=self._get_content_type(file, id, content_type) + self.update_data(file, content_type) + + security.declarePrivate('save') + def save(self, file): + bf = self.bdata.open('w') + bf.write(file.read()) + self.size = bf.tell() + bf.close() + + security.declarePrivate('open') + def open(self, mode='r'): + bf = self.bdata.open(mode) + return bf + + security.declarePrivate('updateSize') + def updateSize(self, size=None): + if size is None : + bf = self.open('r') + bf.seek(0,2) + self.size = bf.tell() + bf.close() + else : + self.size = size + + def _getLegacyData(self) : + warn("Accessing 'data' attribute may be inefficient with " + "this blob based file. You should refactor your product " + "by accessing data like: " + "f = self.open('r') " + "data = f.read()", + DeprecationWarning, stacklevel=2) + f = self.open() + data = f.read() + f.close() + return data + + def _setLegacyData(self, data) : + warn("Accessing 'data' attribute may be inefficient with " + "this blob based file. You should refactor your product " + "by accessing data like: " + "f = self.save(data)", + DeprecationWarning, stacklevel=2) + if isinstance(data, str) : + sio = StringIO() + sio.write(data) + sio.seek(0) + data = sio + self.save(data) + + data = property(_getLegacyData, _setLegacyData, + "Data Legacy attribute to ensure compatibility " + "with derived classes that access data by this way.") def id(self): return self.__name__ @@ -251,36 +298,11 @@ class File(Persistent, Implicit, PropertyManager, RESPONSE.setHeader('Content-Range', 'bytes %d-%d/%d' % (start, end - 1, self.size)) RESPONSE.setStatus(206) # Partial content - - data = self.data - if isinstance(data, str): - RESPONSE.write(data[start:end]) - return True - - # Linked Pdata objects. Urgh. - pos = 0 - while data is not None: - l = len(data.data) - pos = pos + l - if pos > start: - # We are within the range - lstart = l - (pos - start) - - if lstart < 0: lstart = 0 - - # find the endpoint - if end <= pos: - lend = l - (pos - end) - - # Send and end transmission - RESPONSE.write(data[lstart:lend]) - break - - # Not yet at the end, transmit what we have. - RESPONSE.write(data[lstart:]) - - data = data.next - + + bf = self.open('r') + bf.seek(start) + RESPONSE.write(bf.read(size)) + bf.close() return True else: @@ -310,11 +332,13 @@ class File(Persistent, Implicit, PropertyManager, draftprefix, boundary)) RESPONSE.setStatus(206) # Partial content - data = self.data - # The Pdata map allows us to jump into the Pdata chain - # arbitrarily during out-of-order range searching. - pdata_map = {} - pdata_map[0] = data + + bf = self.open('r') +# data = self.data +# # The Pdata map allows us to jump into the Pdata chain +# # arbitrarily during out-of-order range searching. +# pdata_map = {} +# pdata_map[0] = data for start, end in ranges: RESPONSE.write('\r\n--%s\r\n' % boundary) @@ -324,51 +348,12 @@ class File(Persistent, Implicit, PropertyManager, 'Content-Range: bytes %d-%d/%d\r\n\r\n' % ( start, end - 1, self.size)) - if isinstance(data, str): - RESPONSE.write(data[start:end]) - - else: - # Yippee. Linked Pdata objects. The following - # calculations allow us to fast-forward through the - # Pdata chain without a lot of dereferencing if we - # did the work already. - first_size = len(pdata_map[0].data) - if start < first_size: - closest_pos = 0 - else: - closest_pos = ( - ((start - first_size) >> 16 << 16) + - first_size) - pos = min(closest_pos, max(pdata_map.keys())) - data = pdata_map[pos] - - while data is not None: - l = len(data.data) - pos = pos + l - if pos > start: - # We are within the range - lstart = l - (pos - start) - - if lstart < 0: lstart = 0 - - # find the endpoint - if end <= pos: - lend = l - (pos - end) - - # Send and loop to next range - RESPONSE.write(data[lstart:lend]) - break - - # Not yet at the end, transmit what we have. - RESPONSE.write(data[lstart:]) - - data = data.next - # Store a reference to a Pdata chain link so we - # don't have to deref during this request again. - pdata_map[pos] = data - - # Do not keep the link references around. - del pdata_map + + size = end - start + bf.seek(start) + RESPONSE.write(bf.read(size)) + + bf.close() RESPONSE.write('\r\n--%s--\r\n' % boundary) return True @@ -422,16 +407,13 @@ class File(Persistent, Implicit, PropertyManager, self.ZCacheable_set(None) - data=self.data - if isinstance(data, str): - RESPONSE.setBase(None) - return data - - while data is not None: - RESPONSE.write(data.data) - data=data.next - - return '' + bf = self.open('r') + chunk = bf.read(CHUNK_SIZE) + while chunk : + RESPONSE.write(chunk) + chunk = bf.read(CHUNK_SIZE) + bf.close() + return '' security.declareProtected(View, 'view_image_or_file') def view_image_or_file(self, URL1): @@ -445,19 +427,25 @@ class File(Persistent, Implicit, PropertyManager, """ Allow file objects to be searched. """ if self.content_type.startswith('text/'): - return str(self.data) + bf = self.open('r') + data = bf.read() + bf.close() + return data return '' security.declarePrivate('update_data') - def update_data(self, data, content_type=None, size=None): - if isinstance(data, unicode): + def update_data(self, file, content_type=None): + if isinstance(file, unicode): raise TypeError('Data can only be str or file-like. ' 'Unicode objects are expressly forbidden.') + elif isinstance(file, str) : + sio = StringIO() + sio.write(file) + sio.seek(0) + file = sio if content_type is not None: self.content_type=content_type - if size is None: size=len(data) - self.size=size - self.data=data + self.save(file) self.ZCacheable_invalidate() self.ZCacheable_set(None) self.http__refreshEtag() @@ -476,7 +464,7 @@ class File(Persistent, Implicit, PropertyManager, if precondition: self.precondition=str(precondition) elif self.precondition: del self.precondition if filedata is not None: - self.update_data(filedata, content_type, len(filedata)) + self.update_data(filedata, content_type) else: self.ZCacheable_invalidate() @@ -496,95 +484,23 @@ class File(Persistent, Implicit, PropertyManager, if self.wl_isLocked(): raise ResourceLockedError, "File is locked via WebDAV" - data, size = self._read_data(file) - content_type=self._get_content_type(file, data, self.__name__, + content_type=self._get_content_type(file, self.__name__, 'application/octet-stream') - self.update_data(data, content_type, size) - - notify(ObjectModifiedEvent(self)) - + self.update_data(file, content_type) + if REQUEST: message="Saved changes." return self.manage_main(self,REQUEST,manage_tabs_message=message) - def _get_content_type(self, file, body, id, content_type=None): + def _get_content_type(self, file, id, content_type=None): headers=getattr(file, 'headers', None) if headers and headers.has_key('content-type'): content_type=headers['content-type'] else: - if not isinstance(body, str): body=body.data - content_type, enc=guess_content_type( - getattr(file, 'filename',id), body, content_type) + name = getattr(file, 'filename', self.uploaded_filename) or id + content_type, enc=guess_content_type(name, '', content_type) return content_type - def _read_data(self, file): - import transaction - - n=1 << 16 - - if isinstance(file, str): - size=len(file) - if size < n: return file, size - # Big string: cut it into smaller chunks - file = StringIO(file) - - if isinstance(file, FileUpload) and not file: - raise ValueError, 'File not specified' - - if hasattr(file, '__class__') and file.__class__ is Pdata: - size=len(file) - return file, size - - seek=file.seek - read=file.read - - seek(0,2) - size=end=file.tell() - - if size <= 2*n: - seek(0) - if size < n: return read(size), size - return Pdata(read(size)), size - - # Make sure we have an _p_jar, even if we are a new object, by - # doing a sub-transaction commit. - transaction.savepoint(optimistic=True) - - if self._p_jar is None: - # Ugh - seek(0) - return Pdata(read(size)), size - - # Now we're going to build a linked list from back - # to front to minimize the number of database updates - # and to allow us to get things out of memory as soon as - # possible. - next = None - while end > 0: - pos = end-n - if pos < n: - pos = 0 # we always want at least n bytes - seek(pos) - - # Create the object and assign it a next pointer - # in the same transaction, so that there is only - # a single database update for it. - data = Pdata(read(end-pos)) - self._p_jar.add(data) - data.next = next - - # Save the object so that we can release its memory. - transaction.savepoint(optimistic=True) - data._p_deactivate() - # The object should be assigned an oid and be a ghost. - assert data._p_oid is not None - assert data._p_state == -1 - - next = data - end = pos - - return next, size - security.declareProtected(delete_objects, 'DELETE') security.declareProtected(change_images_and_files, 'PUT') @@ -596,10 +512,9 @@ class File(Persistent, Implicit, PropertyManager, file=REQUEST['BODYFILE'] - data, size = self._read_data(file) - content_type=self._get_content_type(file, data, self.__name__, - type or self.content_type) - self.update_data(data, content_type, size) + content_type = self._get_content_type(file, self.__name__, + type or self.content_type) + self.update_data(file, content_type) RESPONSE.setStatus(204) return RESPONSE @@ -611,7 +526,11 @@ class File(Persistent, Implicit, PropertyManager, Returns the size of the file or image. """ size=self.size - if size is None: size=len(self.data) + if size is None : + bf = self.open('r') + bf.seek(0,2) + self.size = size = bf.tell() + bf.close() return size # deprecated; use get_size! @@ -648,16 +567,11 @@ class File(Persistent, Implicit, PropertyManager, RESPONSE.setHeader('Content-Length', self.size) return result - data = self.data - if isinstance(data, str): - RESPONSE.setBase(None) - return data - - while data is not None: - RESPONSE.write(data.data) - data = data.next - - return '' + bf = self.open('r') + data = bf.read() + bf.close() + RESPONSE.setBase(None) + return data manage_addImageForm=DTMLFile('dtml/imageAdd',globals(), Kind='Image',kind='image') @@ -677,19 +591,9 @@ def manage_addImage(self, id, file, title='', precondition='', content_type='', id, title = cookId(id, title, file) self=self.this() + self._setObject(id, Image(id,title,file,content_type, precondition)) - # First, we create the image without data: - self._setObject(id, Image(id,title,'',content_type, precondition)) - newFile = self._getOb(id) - - # Now we "upload" the data. By doing this in two steps, we - # can use a database trick to make the upload more efficient. - if file: - newFile.manage_upload(file) - if content_type: - newFile.content_type=content_type - notify(ObjectCreatedEvent(newFile)) if REQUEST is not None: @@ -699,14 +603,14 @@ def manage_addImage(self, id, file, title='', precondition='', content_type='', return id -def getImageInfo(data): - data = str(data) - size = len(data) +def getImageInfo(file): height = -1 width = -1 content_type = '' # handle GIFs + data = file.read(24) + size = len(data) if (size >= 10) and data[:6] in ('GIF87a', 'GIF89a'): # Check to see if content_type is correct content_type = 'image/gif' @@ -735,7 +639,8 @@ def getImageInfo(data): # handle JPEGs elif (size >= 2) and (data[:2] == '\377\330'): content_type = 'image/jpeg' - jpeg = StringIO(data) + jpeg = file + jpeg.seek(0) jpeg.read(2) b = jpeg.read(1) try: @@ -761,7 +666,7 @@ class Image(File): as File objects. Images also have a string representation that renders an HTML 'IMG' tag. """ - meta_type='Image' + meta_type='Blob Image' security = ClassSecurityInfo() security.declareObjectProtected(View) @@ -813,29 +718,29 @@ class Image(File): manage_uploadForm=manage_editForm security.declarePrivate('update_data') - def update_data(self, data, content_type=None, size=None): - if isinstance(data, unicode): - raise TypeError('Data can only be str or file-like. ' - 'Unicode objects are expressly forbidden.') + def update_data(self, file, content_type=None): + super(Image, self).update_data(file, content_type) + self.updateFormat(size=self.size, content_type=content_type) - if size is None: size=len(data) - - self.size=size - self.data=data - - ct, width, height = getImageInfo(data) - if ct: - content_type = ct - if width >= 0 and height >= 0: - self.width = width - self.height = height - - # Now we should have the correct content type, or still None - if content_type is not None: self.content_type = content_type - - self.ZCacheable_invalidate() - self.ZCacheable_set(None) - self.http__refreshEtag() + security.declarePrivate('updateFormat') + def updateFormat(self, size=None, dimensions=None, content_type=None): + self.updateSize(size=size) + + if dimensions is None or content_type is None : + bf = self.open('r') + ct, width, height = getImageInfo(bf) + bf.close() + if ct: + content_type = ct + if width >= 0 and height >= 0: + self.width = width + self.height = height + + # Now we should have the correct content type, or still None + if content_type is not None: self.content_type = content_type + else : + self.width, self.height = dimensions + self.content_type = content_type def __str__(self): return self.tag() @@ -910,30 +815,3 @@ def cookId(id, title, file): filename.rfind(':'), )+1:] return id, title - -class Pdata(Persistent, Implicit): - # Wrapper for possibly large data - - next=None - - def __init__(self, data): - self.data=data - - def __getslice__(self, i, j): - return self.data[i:j] - - def __len__(self): - data = str(self) - return len(data) - - def __str__(self): - next=self.next - if next is None: return self.data - - r=[self.data] - while next is not None: - self=next - r.append(self.data) - next=self.next - - return ''.join(r)