zms._blobfields

module documentation

(source)

_blobfields.py - Blob, Image, and File Field Management for ZMS

Blob fields are content attributes that store binary data (images, documents) within ZMS objects. This module provides the foundational classes and utilities for the entire blob field subsystem, enabling seamless integration of file uploads, secure access control, efficient HTTP delivery, and flexible storage backends.

License: GNU General Public License v2 or later, Organization: ZMS Publishing

Class	`MyBlob`	Base class for binary large objects (blobs) stored in ZMS.
Class	`MyBlobDelegate`	Simple delegate wrapper for blob objects.
Class	`MyBlobWrapper`	Wrapper for external Zope file objects to provide blob-like interface.
Class	`MyFile`	ZMS file blob class for managing binary and text files.
Class	`MyImage`	ZMS image blob class for managing image files with metadata.
Function	`bytes_hex`	Convert binary or text data to a hexadecimal string.
Function	`createBlobField`	Create a blob field instance and initialize it from uploaded data.
Function	`getLangFilename`	Append a language suffix to a filename when needed.
Function	`recurse_downloadRessources`	Export blob resources from the ZODB to the filesystem.
Function	`rfc1123_date`	Format a UNIX timestamp as an RFC 1123 HTTP date.
Function	`thumbnailImage`	Generate a thumbnail image from one image attribute into another.
Function	`thumbnailImageFields`	Generate configured thumbnail variants for all image fields.
Function	`uploadBlobField`	Build a blob field from raw uploaded content.

def bytes_hex(data): (source) ¶

Convert binary or text data to a hexadecimal string.

Parameters
data:`bytes` or `str`	Input data
Returns
`str`	Hexadecimal representation

def createBlobField(self, objtype, file=b''): (source) ¶

Create a blob field instance and initialize it from uploaded data.

Parameters
self	ZMS context object
objtype:`str`	Desired blob type
file:`bytes`, file-like, or `dict`	Uploaded file data or metadata dictionary
Returns
`MyImage` or `MyFile`	Created blob object

def getLangFilename(self, filename, lang): (source) ¶

Append a language suffix to a filename when needed.

Parameters
self	ZMS context object
filename:`str`	Original filename
lang:`str`	Language identifier
Returns
`str`	Language-aware filename

def recurse_downloadRessources(self, base_path, REQUEST): (source) ¶

Export blob resources from the ZODB to the filesystem.

Parameters
self	ZMS context object
base_path:`str`	Export base path
REQUEST	Zope request object
Returns
`list`	Exported resource metadata entries

def rfc1123_date(dt): (source) ¶

Format a UNIX timestamp as an RFC 1123 HTTP date.

Parameters
dt:`float` or `int`	Timestamp value
Returns
`str`	RFC 1123 formatted date string

def thumbnailImage(self, hiresKey, loresKey, maxdim, lang, REQUEST): (source) ¶

Generate a thumbnail image from one image attribute into another.

Parameters
self	ZMS context object
hiresKey:`str`	Source image attribute id
loresKey:`str`	Target image attribute id
maxdim:`int`	Maximum thumbnail dimension
lang:`str`	Language identifier
REQUEST	Zope request object
Returns
`str`	Status message

def thumbnailImageFields(self, lang, REQUEST): (source) ¶

Generate configured thumbnail variants for all image fields.

Parameters
self	ZMS context object
lang:`str`	Language identifier
REQUEST	Zope request object
Returns
`str`	Status message

def uploadBlobField(self, clazz, file=b'', filename=''): (source) ¶

Build a blob field from raw uploaded content.

Parameters
self	ZMS context object
clazz	Requested blob datatype or class
file:`bytes`, `str`, or file-like	Uploaded file content
filename:`str`	Original filename
Returns
`MyImage` or `MyFile`	Initialized blob object