Re: [libvirt-users] stream finish throws exception via python API

On 26.04.16 15:30, Shahar Havivi wrote: > On 26.04.16 14:14, Shahar Havivi wrote: >> On 25.04.16 09:11, Cole Robinson wrote: >>> On 04/25/2016 08:10 AM, Shahar Havivi wrote: >>>> On 17.04.16 15:41, Shahar Havivi wrote: >>>>> Hi, >>>>> The following snippet works fine e.g. receiving the data but when calling >>>>> stream.finish() we get the following error: >>>>> >>>>> stream = con.newStream() >>>>> vol.download(stream, 0, 0, 0) >>>>> buf = stream.recv(1024) >>>>> stream.finish() >>>>> >>>>> libvirt: I/O Stream Utils error : internal error: I/O helper exited abnormally >>>>> Traceback (most recent call last): >>>>> File "./helpers/kvm2ovirt", line 149, in <module> >>>>> download_volume(vol, item[1], diskno, disksitems, pksize) >>>>> File "./helpers/kvm2ovirt", line 102, in download_volume >>>>> stream.finish() >>>>> File "/usr/lib64/python2.7/site-packages/libvirt.py", line 5501, in finish >>>>> if ret == -1: raise libvirtError ('virStreamFinish() failed') >>>>> libvirt.libvirtError: internal error: I/O helper exited abnormally >>>>> >>> >>> The error message sucks, I'll send patches to improve it a little at least. >>> >>> What's happening here is that the you haven't read all the data you requested >>> (it's vol.download(path, offset, length, flags), length == 0 means read the >>> whole file which I suspect you haven't done). In this case the iohelper >>> program that libvirt uses won't complete feeding us all the data, and it exits >>> with SIGPIPE when we close the read end of the pipe. >>> >>> Now whether that should actually be an error condition is open to debate. >>> virStreamFinish docs make it sound like it's legitimate to throw an error if >>> it appears that all requested data wasn't read. >> Thanks checking... > Thanks Cole, > I modify our script and for checking if stream.recv() returns zero the finish > works fine. > Our API needs to know the size of bytes that you are going to stream back > which is not provided by the allocation and capacity. > (ie the same as du -s /path/to/disk) > > Shahar. We need the size of the image "Image end offset" you get from "qemu-img check", Does libvirt have an API for that?