Please use http://developer.ubuntu.com/packaging/html/getting-set-up.html instead.

Getting Set Up

There are a number of things you need to do in the beginning to enable you to do Ubuntu development. A few of them you have to do locally on your system. In addition to that you also need to inform Launchpad about yourself, so it accepts changes you want to make.

When you followed all the steps in this article,

• you have all the tools to do Ubuntu development installed on your machine,
• your local developer tools know about you, which simplifies work a lot,
• you can do local builds of packages,
• you can interact with other developers and propose your changes on Launchpad to get merged,
• you can upload packages to Launchpad, so they are hosted in your Personal Package Archive (PPA).

Running the development version

It is advisable to run the current development version of Ubuntu. It will allow you to test changes in a “live environment” where they are actually built and tested in the development release you upload them to.

UsingDevelopmentReleases shows a variety of ways to use the development release in a safe way.

Installing tools locally

Just run:

sudo apt-get install gnupg pbuilder ubuntu-dev-tools bzr-builddeb gobject-introspection

and you should have all the tools you will need in the beginning.

• gnupg you will need to create a GPG key with which you will sign files you want to upload to Launchpad.

• pbuilder is a great tool to do a reproducible build of a package in a clean and isolated environment.

• ubuntu-dev-tools (and devscripts, a direct dependency) provide you with a collection of tools that make a lot of packaging tasks a lot easier.

• bzr-builddeb (and bzr, a dependency) will get you set up for working in the distributed development environment, that makes it easy for many developers to collaborate and work on the same code while keeping it trivial to merge each others work.

• gobject-introspection is necessary to build the source package from the branch contents with bzr-builddeb.

Setting up a GPG key

GPG stands for GNU Privacy Guard and implements the OpenPGP standard which allows you to sign and encrypt messages and files. This is useful for a number of purposes. In our case it is important that you can sign files with your key, so they can be identified as something that you worked on. If you upload a source package to Launchpad, it will only accept the package if it can tell who uploaded the package.

To generate a new GPG key, run:

gpg --gen-key

GnuPG will first ask you which kind of key you want to generate. Choosing the default (RSA and DSA) is fine. Next it will ask you about the keysize. Choose 4096 for high security. Afterwards it will ask you if you want it to expire the key at some stage. It is safe to say “0”, which means the key will never expire. The last questions will be about your name and email address. Just pick the ones you are going to use for Ubuntu development here, you can add additional email addresses later on. Adding a comment is not necessary. Then you will have to set a passphrase. Choose a safe one. Now GnuPG will create a key for you, which can take a little bit of time, as it needs random bytes, so if you give the system some work to do it will be just fine.

Once this is done, you will get a message similar to this one:

pub   4096R/43CDE61D 2010-12-06
      Key fingerprint = 5C28 0144 FB08 91C0 2CF3  37AC 6F0B F90F 43CD E61D
uid                  Daniel Holbach <dh@mailempfang.de>
sub   4096R/51FBE68C 2010-12-06

In this case 43CDE61D is the key ID.

To upload (the public part of) of your key to a keyserver, so the world can identify messages and files as yours, just run:

gpg --send-keys KEY-ID

There is a network of keyservers that will automatically sync the key between them.

Setting up an SSH key

SSH is a network protocol that allows you to exchange data in a secure way over the network. In a lot of cases you will use it to access and open a shell on another machine. It is also very useful to transfer files in a secure way.

To generate a SSH key, run:

ssh-keygen -t rsa

The default filename makes sense, you can just leave it as it is. Also you can choose to use a passphrase or not.

We will use the SSH key to securely push code changes to Launchpad.

Setting up pbuilder

pbuilder allows you to build packages locally on your machine. It serves a couple of purposes:

• the build will be done in a minimal and clean environment, where you can see if it succeeds in a reproducible way (with no modifications of the local system
• there is no need to install all necessary build-dependencs locally
• you can set up multiple instances for various Ubuntu and Debian releases

Setting pbuilder up is very easy. Edit ~/.pbuilderrc and add the following line to it:

COMPONENTS="main universe multiverse restricted"

This will ensure that build-dependencies are satisfied using all components.

Then run:

pbuilder-dist <release> create

where <release> is for example natty, maverick, lucid or in the case of Debian maybe sid. This will take a while as it will download all the necessary packages for a "minimal installation". These will be cached though.

Setting up your development environment

Teaching Bazaar about you

Bazaar is the tool we use to store code changes in a logical way, to exchange proposed changes and merge them, even if development is done concurrently.

To tell Bazaar who you are, simply run:

bzr whoami "Frank Chu <fchu@example.com>"
bzr launchpad-login fchu

whoami will tell Bazaar which name and email address it should use for your commit messages. With launchpad-login you set your Launchpad ID. This way code that you publish in Launchpad will be associated with you.

Note: If you can not remember the ID, go to https://launchpad.net/~ and see where it redirects you. The part after the "~" in the URL is your Launchpad ID.)

Introducing you to the development tools

Similar to Bazaar, the Debian/Ubuntu packaging tools need to learn about you as well. Simply open your ~/.bashrc in a text editor and add something like this to the bottom of it:

export DEBFULLNAME="Frank Chu"
export DEBEMAIL="fchu@example.com"

Now save the file and either restart your terminal or run:

source ~/.bashrc

(If you use a shell other than the default, which is bash, please edit the configuration file for that shell accordingly.)

Launchpad

Launchpad is the central piece of infrastructure we use in Ubuntu. It stores not only our packages and our code, but also things like translations, bug reports, information about the people who work on Ubuntu and which teams they are part of.

You will need to register with Launchpad and give it some information about you so you can get started and it will accept packages, bug reports, code branches, etc. from you.

Setting up a profile

Generally it should be enough to head to https://launchpad.net/+login and enter your email address. It will send back an email to you with a link you need to open in your browser. (If you do not receive it, check in your Spam folder too.)

Next you will have to choose a display name. Almost everybody just uses their real name here.

https://help.launchpad.net/YourAccount/NewAccount has more information about the process and additional settings you can change.

Uploading the GPG key to Launchpad

To find about your GPG fingerprint, run:

gpg --fingerprint email@address.com

and it will print out something like:

pub   4096R/43CDE61D 2010-12-06
      Key fingerprint = 5C28 0144 FB08 91C0 2CF3  37AC 6F0B F90F 43CD E61D
uid                  Daniel Holbach <dh@mailempfang.de>
sub   4096R/51FBE68C 2010-12-06

Head to https://launchpad.net/~/+editpgpkeys and copy the part about your "Key fingerprint" into the text box. In the case above this would be 5C28 0144 FB08 91C0 2CF3  37AC 6F0B F90F 43CD E61D. Now click on "Import Key".

Launchpad will use the fingerprint to check the Ubuntu key server for your key and, if successful, send you an encrypted email asking you to confirm the key import. Check your email account and read the email that Launchpad sent you. If your email client supports OpenPGP encryption, it will prompt you for the password you chose for the key when GPG generated it. Enter the password, then click the link to confirm that the key is yours.

Launchpad encrypts the email, using your public key, so that it can be sure that the key is yours. If your email software does not support OpenPGP encryption, copy the encrypted email’s contents, type gpg in your terminal, then paste the email contents into your terminal window.

Back on the Launchpad website, use the Confirm button and Launchpad will complete the import of your OpenPGP key.

Find more information at https://help.launchpad.net/YourAccount/ImportingYourPGPKey

Uploading your SSH key

Open https://launchpad.net/~/+editsshkeys in a web browser, also open ~/.ssh/id_rsa.pub in a text editor. It is the public part of your SSH key, so it is safe to share it with Launchpad. Copy the contents of the file and paste them into the text box on the web page that says "Add an SSH key". Now click "Import Public Key".

More information is available at https://help.launchpad.net/YourAccount/CreatingAnSSHKeyPair

CategoryUbuntuDevelopment