It still lacks the right HTML report (the builtin report is very pretty, but
lacks the "lines uncovered" numbers that I want), and the half-finished
delta-from-last-run measurements.
This can be useful if one of the ones that he has already begun downloading fails. See #287 for discussion. This fixes part of #287 which part was a regression caused by #928, namely this fixes fail-over in case a share is corrupted (or the server returns an error or disconnects). This does not fix the related issue mentioned in #287 if a server hangs and doesn't reply to requests for blocks.
This should put an end to the phenomenon I've been seeing that a single hung server can cause all downloads on a grid to hang. Also it should speed up all downloads by (a) not-waiting for responses to queries that it doesn't need, and (b) downloading shares from the servers which answered the initial query the fastest.
Also, do not count how many buckets you've gotten when deciding whether the download has enough shares or not -- instead count how many buckets to *unique* shares that you've gotten. This appears to improve a slightly weird behavior in the current download code in which receiving >= K different buckets all to the same sharenumber would make it think it had enough to download the file when in fact it hadn't.
This patch needs tests before it is actually ready for trunk.
Having both test_node() and test_client() (one of which calls the other) felt
confusing to me, so I changed it to have test_node(), test_client(), and a
common do_create() helper method.
This patch displays a warning to the user in two cases:
1. When special files like symlinks, fifos, devices, etc. are found in the
local source.
2. If files or directories are not readables by the user running the 'tahoe
backup' command.
In verbose mode, the number of skipped files and directories is printed at the
end of the backup.
Exit status returned by 'tahoe backup':
- 0 everything went fine
- 1 the backup failed
- 2 files were skipped during the backup
allmydata.util.log.err() either takes a Failure as the first positional
argument, or takes no positional arguments and must be invoked in an
exception handler. Fixed its signature to match both foolscap.logging.log.err
and twisted.python.log.err . Included a brief unit test.
Stop checking separately for ConnectionDone/ConnectionLost, since those have
been folded into DeadReferenceError since foolscap-0.3.1 . Write
rrefutil.trap_deadref() in terms of rrefutil.trap_and_discard() to improve
code coverage.
Verifier misses
The results (described in #819) match our expectations: it misses corruption
in unused share fields and in most container fields (which are only visible
to the storage server, not the client). 1265 bytes of a 2753 byte
share (hosting a 56-byte file with an artifically small segment size) are
unused, mostly in the unused tail of the overallocated UEB space (765 bytes),
and the allocated-but-unwritten plaintext_hash_tree (480 bytes).
The bug was that a disconnected server could cause us to re-enter the initial
loop() call, sending multiple queries to a single server, provoking an
incorrect UCWE. To fix it, stall the loop() with an eventual.fireEventually()
