288280 - if WAN-connection is lost downloadmanager does not give an error-indication nor is it possible to resume the download from the point where it got stuck

Status: RESOLVED DUPLICATE of bug 254544

(Toolkit :: Downloads API, defect)

Description

[Jerommeke]

User-Agent:       Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.7.6) Gecko/20050317 Firefox/1.0.2
Build Identifier: Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.7.6) Gecko/20050317 Firefox/1.0.2

When the WAN-connection is lost for any reason while downloading a file via FTP
(filesize does not matter), the downloadmanager (and Firefox itself) seems not
to notice this event and will not mark the download(s) with error. When the
WAN-connection is re-established the stuck download(s) will not automatically
resume, nor is it possible to manually resume, even after pausing the stuck
download(s) and then pressing resume.
There are two methods for completing the download: The first is to CANCEL the
download and then RETRY. This reveils another bug; suddenly the filesize is unknown.
So the best workarround so far when losing the WAN-connection while downloading
is to cancel, delete and completely restart the download.
This bug might be the core-bug for a lot of reported bugs.
Good luck with the solution! 

Reproducible: Always

Steps to Reproduce:
1. Start downloading a file ( via FTP, see given URL)
2. Pull the plug (disconnect WAN manually)
3. reconnect WAN-connection


Actual Results:  
Look in downloadmanager, download got stuck, no error indication nor any
possibility to resume, even after pausing and then resuming. The download will
not reconnect and that is most annoying when downloading a file of 750MB.

Expected Results:  
Downloadmanager should have noticed the disconnection-event, should have changed
the status of all stuck downloads in "error", and should have given the user the
 possibility to resume the FTP-download(s) without losing the data already
downloaded, because that is the real beauty of a ftp-download. :-)

WIN2K platform on a laptop, connected with the internet via ethernet PCMCIA card
connected to an ADSL-router.

Comment 1

[Jerommeke]

Now tested with TRUNK VERSION Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US;
rv:1.8b2) Gecko/20050330 Firefox/1.0+.
The downloadmanager now detects the connection to be lost and gives a message
that <src_filename>.part could not be saved because the sourcefile could not be
read. It now cancels the download in stead of pausing it.
So appart from the new message and the canceling(?) of the download the rest of
the bug still remains for it is not possible in any way to resume a FTP download
after the connection is re-established. It should be possible however for there
exists a PART-file which should contain the already downloaded data.
Retry is the only option now which completely restarts the download and leaves
the PART-file as garbage on ur HD.
Another remarkable detail is that when the connection stays intact and I do a
pause and a few minutes after that a resume, the rusume function works perfect. 
But when if I pause a ( FTP)download, disconnect and reconnect the
WAN-connection, and resume the download, the download gets the status DONE while
it isn't by far. All this is reproducable EVERY time.
See also bug 254544 which I will re-open know.

Comment 2

[Jerommeke]

*** This bug has been marked as a duplicate of 254544 ***