The current output of 'blockjob [--info]' is a single line
designed for human consumption; it's not very nice for machine
parsing. Furthermore, I have plans to modify the line in
response to the new flag for controlling bandwidth units.
Solve that by adding a --raw parameter, which outputs
information closer to the C struct.
$ virsh blockjob testvm1 vda --raw
type=Block Copy
bandwidth=1
cur=197120
end=197120
The information is indented, because I'd like for a later patch
to add a mode that iterates over all the vm's disks with status
for each; in that mode, each block name would be listed unindented
before information (if any) about that block.
Now that we have a raw mode, we can guarantee that it won't change
format over time. Any app that cares about parsing the output can
try --raw, and if it fails, know that it was talking to an older
virsh and fall back to parsing the human-readable format which had
not changed until now; meanwhile, when not using --raw, we have
freed future virsh to change the output to whatever makes sense.
My first change to human mode: this command now guarantees a line
is printed on successful use of the API, even when the API did
not find a current block job (consistent with the rest of virsh).
Bonus:
https://bugzilla.redhat.com/show_bug.cgi?id=1135441
complained that this message was confusing:
$ virsh blockjob test1 hda --async --bandwidth 10
error: conflict between --abort, --info, and --bandwidth modes
even though the man page already documents that --async implies
abort mode, all because '--abort' wasn't present in the command
line. Since I'm adding another case where options are tied
to or imply a mode, I changed that error to:
error: conflict between abort, info, and bandwidth modes
* tools/virsh-domain.c (cmdBlockJob): Add --raw parameter; tweak
error wording.
* tools/virsh.pod (blockjob): Document it.
Signed-off-by: Eric Blake <eblake(a)redhat.com>
---
tools/virsh-domain.c | 31 +++++++++++++++++++++++--------
tools/virsh.pod | 19 ++++++++++++-------
2 files changed, 35 insertions(+), 15 deletions(-)