20851 - Implement partial HTTP caching

Status: VERIFIED WORKSFORME

(Core :: Networking: HTTP, defect, P3)

Description

[Scott Furman]

I don't think any API or implementation changes are necessary in the cache
manager to implement partial caching.  All of the work should be in modifying
the HTTP protocol handler.

The cache manager already tracks whether content is truncated, such status being
made available via nsICachedNetData::GetPartialFlag().  There is also a pair of
accessor methods for the allowPartial flag which controls the cache behavior
with respect to partially-filled cache entries.  The cache can also accommodate
non-zero file offsets when writing to the cache, i.e. so as to be able to append
content to an existing cache entry.

Sending the required byte-range headers in the HTTP request is trivial.  The
somewhat more difficult part will be "gluing" together the previously-cached
content with the newly arrived data from the server.

Comment 1

[Warren Harris]

Mass move of all bugs without target milestones to M13.

Comment 2

[leger]

Bulk move of all Cache (to be deleted component) bugs to new Networking: Cache
component.

Comment 3

[Warren Harris]

Assigning fur's cache bugs to Gordon. He can split them up with davidm.

Comment 4

[Warren Harris]

Moving post beta bugs to M18 which is now the post-beta milestone.

Comment 5

[Gagan]

*** Bug 26469 has been marked as a duplicate of this bug. ***

Comment 6

[Gagan]

->future

Comment 7

[Greg Breland]

This problem still exists on WinNT 2001041704.

The new cache has landed and been around for a while and seems to have become 
pretty stable.

A good example of what this bug will fix is:

1) Dial into the internet(yes people still do this in 3rd world contries)
2) Go look at an big image(not pr0n), something like a screen shot at themes.org
3) Before the image completely downloads, click <back>
4) Look at the image again

Result:
Image will start to download again.

Expected Result:
  Image will resume downloading

Comment 8

[Brian Rogers]

I've seen Netscape 4 successfully resume images and files.  This should probably
be marked 4xp...

Comment 9

[gordon]

Darin, do you have an interest in this?

Comment 10

[Doug Turner (:dougt)]

moving neeti's futured bugs for triaging.

Comment 11

[benc]

-> defaults

Comment 12

[Darin Fisher]

WORKSFORME .. actually a duplicate of a bug i fixed ages ago.

Comment 13

[John Unruh]

Verified WFM.