金字塔+ ZODB图像存储

时间:2013-01-30 20:34:26

标签: python pyramid zodb

我有一个上传表单,接受一个zip文件,并有一个方法解压缩它并从中获取每个文件。从md5哈希中创建一个唯一的id并将它们存储在字典中;

dict[uid] = imagebinary

并返回它,以便表单可以将它们存储到ZODB中。我不能像那样存储图像,因为这个错误吐出来了;

    2013-01-31 08:59:59,061 ERROR [waitress][Dummy-5] Exception when serving /
Traceback (most recent call last):
  File "/home/maverick/inigo/sources/devenv/lib/python2.7/site-packages/waitress-0.8.2-py2.7.egg/waitress/channel.py", line 329, in service
    task.service()
  File "/home/maverick/inigo/sources/devenv/lib/python2.7/site-packages/waitress-0.8.2-py2.7.egg/waitress/task.py", line 173, in service
    self.execute()
  File "/home/maverick/inigo/sources/devenv/lib/python2.7/site-packages/waitress-0.8.2-py2.7.egg/waitress/task.py", line 380, in execute
    app_iter = self.channel.server.application(env, start_response)
  File "/home/maverick/.buildout/eggs/pyramid-1.4-py2.7.egg/pyramid/router.py", line 251, in __call__
    response = self.invoke_subrequest(request, use_tweens=True)
  File "/home/maverick/.buildout/eggs/pyramid-1.4-py2.7.egg/pyramid/router.py", line 227, in invoke_subrequest
    response = handle_request(request)
  File "/home/maverick/inigo/sources/devenv/lib/python2.7/site-packages/pyramid_debugtoolbar-1.0.4-py2.7.egg/pyramid_debugtoolbar/toolbar.py", line 133, in toolbar_tween
    body = tb.render_full(request).encode('utf-8', 'replace')
  File "/home/maverick/inigo/sources/devenv/lib/python2.7/site-packages/pyramid_debugtoolbar-1.0.4-py2.7.egg/pyramid_debugtoolbar/tbtools.py", line 240, in render_full
    summary = self.render_summary(include_title=False, request=request)
  File "/home/maverick/inigo/sources/devenv/lib/python2.7/site-packages/pyramid_debugtoolbar-1.0.4-py2.7.egg/pyramid_debugtoolbar/tbtools.py", line 229, in render_summary
    'description':  description_wrapper % escape(self.exception),
UnicodeDecodeError: 'ascii' codec can't decode byte 0xef in position 114: ordinal not in range(128)

那么,我应该怎么做呢?我几乎坚持这个。

1 个答案:

答案 0 :(得分:2)

您看到的错误与存储在ZODB中的图像无关。

要存储更大的数据,您确实想要使用ZODB Blob,而不是将图像数据直接放在属性中。 Blob分别存储在磁盘上,不会刷新ZODB缓存,并且可以在再次访问时流回客户端。

要创建和存储Blob,请使用:

from ZODB.blob import Blob

uid = Blob(imagebinary.read())

一旦这样创建,您可以稍后使用uid作为文件;你需要先在读或写模式下打开它。例如,要从视图返回blob的内容,请使用:

from pyramid.response import Response

def serveimage(request):
    # retrieve uid from somewhere
    resp = Response(content_type='image/jpeg')
    resp.app_iter = uid.open('r')  # open for reading
    return resp

Blob绑定到事务,如果事务被回滚,则会自动丢弃对它们的更改。