Apache core supports a FileETag directive to customize the attributes that go into creating an etag. In our case, since we have multiple backends, using the inode as part of the etag is not useful, so we removed it. However, we also recently attempted to use davfs2 fuse filesystem with apache, and found the clearly documented note that apache's mod_dav_fs doesn't support customized etags. Since davfs2 uses PROPFIND for directory listings (using mod_dav_fs and a hard coded etag with inode) and GET for actual file retrieval (using core, and thus the customized etag with no inode) it sees the etag as having changed and invalidates its cache of the file on every directory listing.
My question is if there's any justification for why mod_dav_fs hard codes the etag to include inode, or if this would be a reasonable bug report or patch for it to respect the FileETag directive as well. I see this suggested as part of discussion of a different issue here: http://mail-archives.apache.org/mod_mbox/httpd-dev/200710.mbox/%[email protected]%3E but I don't see any evidence that anything happened with it. Joel
