[ZODB-Dev] Re: ZODB 3.8.0b1 is released

[Christian Zagrodnick]

Hi Jim


On 2007-06-11 21:39:03 +0200, Jim Fulton <jim at zope.com> said:

> The ZODB 3.8.0b1 release is available at:
> 
>    http://www.python.org/pypi/ZODB3/3.8.0b1
> 
> The major changes since 3.8.0a1 are in Blobs.  Blobs have been re- 
> factored a fair bit.
> 
> Some backward incompatible changes include:
> 
> - The Blob class is now imported from ZODB.blob.
> 
> - The Blob openDetached method has bee replaced by the committed  
> method.  It is now possible to get a blob file name that can be  handed 
> to external programs for reading.
> 
> - Text-mode blobs are no-longer supported.  All blobs are implicitly  
> in binary mode.  There is no need to specify this in the blob open  
> method.  The valid modes, 'r', 'w', 'a', and 'r+' are all implicitly  
> binary.
> 
> - Calling consumeFile with an open file is no-longer supported.
> 
> I've also made a 3.8 release branch.  Any bug fixes should be applied  
> to the branch, the trunk and earlier branches as appropriate.  Work  
> toward 3.9 can proceed on the trunk.

I started playing with blobs a little bit. And yes, they're working great.

But I have a few things to note:

In combination with ZEO there seem to be various ways to miss-configure 
the blob storage in a way where it *seems* to work. But at a point 
you'll get strange errors an wonder. In my case I shared the blob 
storage with the zeo client w/o telling the zeo client that it actually 
was shared.

I think this should just break, i.e. prevent the ZEO client from making 
a connection. This could be achieved my some marker files in the blob 
directory which would be created on initialization. For instance: 
blobs/.blob-storage or blobs/.blob-cache

This way a client would know that a directory containing the 
.blob-storage must be set up in shared mode.


-- 
Christian Zagrodnick

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