Chapter 3. Mastering Baking with Hob and Toaster

In this chapter, we will explore two powerful tools included in the Yocto Project. In the first part of the chapter, we will speak about Hob, which is a graphical interface for BitBake. In the second part, we will work with Toaster, a web interface that enables you to follow the advanced parts of the build with a simple browser (such as Firefox).

Hob

In order to explore Hob, we will, through this section, sweep through the different essential steps for its proper functioning.

Preparing the environment for Hob

As in Chapter 2 , Building our First Poky Image for the Raspberry Pi, the first step is to initialize the environment. Recall this command:

$ source oe-init-build-env rpi-build

Once the command is launched, the terminal will be redirected to the rpi-build directory.

Running Hob

Now that we have initialized all the variables required to build, we can start the Hob interface with this command:

$ hob

Once you run this command, Hob will try to parse the configuration files (local.conf and bblayers.conf) in order to find the metadata available to create the image. After this step, you will see the interface launch screen, as shown here:

Now, we can choose the desired machine from the list offered by Hob. Select the raspberrypi machine.

Note

The machine option you choose corresponds to the MACHINE variable in the local.conf file.

You will...

Exploring Toaster

Toaster is a web interface for BitBake. The Yocto Project website describes it as follows:

"Toaster is an Application Programming Interface (API) and web-based interface to the OpenEmbedded build system, which uses BitBake. Currently, Toaster collects and presents information about your builds, which you can navigate and query using a web browser"

Installing the required packages for the host system

In order to use Toaster correctly on your preferred Linux distribution, you need to install Django and South:

$ sudo pip install django==1.6
$ sudo pip install South==0.8.4

Note

The pip command makes it easy to install Python modules, in the same way you install packages in a Linux distribution.

Running Toaster

Now that our system is ready to use Toaster, we only have to run it using the following command in order to launch the service:

$ source toaster start

This will give you the following output:

The system will start. Syncing... Creating tables ... Installing custom SQL ......

Summary

In this chapter, we discovered how to use user-friendly interfaces such as Hob and Toaster. We learned the different capabilities of these tools (configuration and functionality). It is worth noting that these tools allow better flexibility for development teams.

In the next chapter, we will learn the main role played by BitBake within the Yocto Project. We will discover the different tasks that enable us to generate packages for our image.