Libguestfs - Jul 2014 - golang binding help

Hello. I'm very happy with libguestfs, but now i'm try to write packer
plugin to strip images:
1) resize filesystem to minimum
2) resize partitions to minimum
3) create/resize file with needed size

But golang binding have not docs. Is that possible to generate
something suitable to godoc.org to determine api methods and
input,output variables for functions?


-- 
Vasiliy Tolstov,
e-mail: v.tolstov@selfip.ru
jabber: vase@selfip.ru

On Fri, Jul 11, 2014 at 06:18:12PM +0400, Vasiliy Tolstov
wrote:
> Hello. I'm very happy with libguestfs, but now i'm try to write
packer
> plugin to strip images:
Packer is: http://www.packer.io/intro ?
> 1) resize filesystem to minimum
> 2) resize partitions to minimum
> 3) create/resize file with needed size
> 
> But golang binding have not docs. Is that possible to generate
> something suitable to godoc.org to determine api methods and
> input,output variables for functions?
So a few different things here:

(a) Yes, we should add golang docs.  However I don't know how to do
that.  If you can point me to some documentation about writing
documentation for golang modules then I'll be glad to add it.

(b) In the meantime you can read the C API documentation (in English,
not Russian -- sorry!)

http://libguestfs.org/guestfs.3.html

and the golang examples:

http://libguestfs.org/guestfs-golang.3.html

and the golang tests:

https://github.com/libguestfs/libguestfs/tree/master/golang/src/libguestfs.org/guestfs

(c) In the API you can resize filesystems using calls like
guestfs_resize2fs / g.Resize2fs and others.  However note that there
is no single API for doing a virt-resize -like operation.  You have to
actually call virt-resize if you want to resize a whole OS disk.

Hope that helps, let me know if you have more questions.

Rich.

-- 
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
Read my programming and virtualization blog: http://rwmj.wordpress.com
virt-builder quickly builds VMs from scratch
http://libguestfs.org/virt-builder.1.html

2014-07-12 0:33 GMT+04:00 Richard W.M. Jones
<rjones@redhat.com>:
> On Fri, Jul 11, 2014 at 06:18:12PM +0400, Vasiliy Tolstov wrote:
>> Hello. I'm very happy with libguestfs, but now i'm try to write
packer
>> plugin to strip images:
>
> Packer is: http://www.packer.io/intro ?
Yes, i'm try to build cloud images using it. Does it possible to add
ability to resize freebsd slices ?
>
>> 1) resize filesystem to minimum
>> 2) resize partitions to minimum
>> 3) create/resize file with needed size
>>
>> But golang binding have not docs. Is that possible to generate
>> something suitable to godoc.org to determine api methods and
>> input,output variables for functions?
>
> So a few different things here:
>
> (a) Yes, we should add golang docs.  However I don't know how to do
> that.  If you can point me to some documentation about writing
> documentation for golang modules then I'll be glad to add it.
>
I think that golang bindings need separate repo, may be autogenerate
bindings and push resulted files to separate github repo.... In this
case peaples can do go get github.com/libguestfs/go-libguestfs and
have a package.  And build it with or without CGO_ENABLED (static or
dynamic). But in case of autogenerated binding i don't know how to
write docs and keep it sync with code...
> (b) In the meantime you can read the C API documentation (in English,
> not Russian -- sorry!)
>
> http://libguestfs.org/guestfs.3.html
>
Not bad.
> and the golang examples:
>
> http://libguestfs.org/guestfs-golang.3.html
>
> and the golang tests:
>
>
https://github.com/libguestfs/libguestfs/tree/master/golang/src/libguestfs.org/guestfs
>
Thanks
> (c) In the API you can resize filesystems using calls like
> guestfs_resize2fs / g.Resize2fs and others.  However note that there
> is no single API for doing a virt-resize -like operation.  You have to
> actually call virt-resize if you want to resize a whole OS disk.
>
> Hope that helps, let me know if you have more questions.
>
> Rich.
I'm try to use bindings and have trouble, that if somebody does not
have installed go package with libguestfs i can't build plugin. I'm
switch to use guestfish on golang code. This is sutable for me.


-- 
Vasiliy Tolstov,
e-mail: v.tolstov@selfip.ru
jabber: vase@selfip.ru