[meta-freescale] problems adding python to build

[Otavio Salvador]

On Thu, Dec 20, 2012 at 4:31 PM, David Van Beveren <vbdavid at gmail.com> wrote:
> I have been exploring yocto for the Freescale ARM boards (I have an
> i.MX28-evk) for about 2 weeks now. I understand all of the basics but have
> not had much success customizing the images.
>
> I am using the danny release.
>
> Goal:
> I would like to build an image that contains:
>  python and pyopenssl
>  lighttpd
>  a local gnu toolchain on the target
>  gdb / gdbserver
>  NFS server and client
>  sshd
>  the Google API python client library (typically installed with
> easy-install)
>  My own python program
>  My own C++ apps
>
> I have had success configuring the kernel and busybox already using bitbake.
> (I have turned on IPv6, NFSserver, ftp, etc)
>
> I am able to build the standard images (e.g. core-image-minimal, -lsb, and
> -lsb-sdk)
>
> I have  had some problems experimenting with hob. However, this seems to
> just add another layer, and I am just as comfortable doing this by hand.
>
> My approach has been to create a copy of the .bb file for the image, in the
> same folder as the original, (poky/meta/recipies-core/images)  then edit
> that file.
>    Side Q: Is this the best approach? Should I be adding files to the
> sources folder or should I be keeping them outside?

It is not; the best is to have your own layer with your recipes and
images. This easy the maintainence and upgrade for future releases of
Yocto.

> Here is one cut at my image file, my-image-lighttpd, between the dashes:
>
> ----
> require core-image-minimal.bb
> IMAGE_INSTALL += "python_2.7.3 lighttpd"
> ----

No version, use python only.

> I get a message in response that 'nothing PROVIDES python_2.7.3' This is
> confusing to me because  I can see such a recipe:
> poky/meta/recipes-devtools/python/python_2.7.3.bb

You should look at Yocto documentation to learn more  about this but
in short terms you never install a specific version of a recipe but
what it provides. In this case python.

> NOTE that when I remove the python entry and just keep the lighttpd entry it
> works fine.
>
> The Yocto docs talk about a variety of approaches to customizing images,
> from editing local.conf to creating a new layer. I am interested in the
> simplest approach that does not run against the grain of what the designer
> intended.
>
> Once I am able to add the Python packages I think I will understand enough
> to move on.

Use a layer; it makes easier for you to improve it later. local.conf
is nice for experimentation and tests, not for products.

> I believe that the fsl/yocto/poky/oe pltform is the bet embedded build
> platform I have seen. I have used buildroot in the past and when I started
> working on this Freescale board I dove in to ltib but quickly thought about
> moving to either OE or buildroot, when I discovered Yocto and your group. It
> is a very impressive open source project, and I am looking forward to
> contributing where I can.

I am very happy to know it. That's the goal. :-)

Regards,

--
Otavio Salvador                             O.S. Systems
E-mail: otavio at ossystems.com.br  http://www.ossystems.com.br
Mobile: +55 53 9981-7854              http://projetos.ossystems.com.br