MAAS follows the Launchpad Python Style
Guide, except where it gets
Launchpad specific, and where it talks about method
naming. MAAS instead
adopts PEP-8 naming in all cases,
so method names should usually use the
You can grab MAAS's code manually from Launchpad but Bazaar makes it easy to fetch the last version of the code. First of all, install Bazaar:
sudo apt-get install bzr
Then go into the directory where you want the code to reside and run:
bzr branch lp:maas maas && cd maas
MAAS depends on Postgres 9.1, Apache 2, daemontools, pyinotify, and many other packages. To install everything that's needed for running and developing MAAS, run:
Careful: this will
apt-get install many packages on your system, via
It may prompt you for your password.
This will install
bind9. As a result you will have an extra daemon running.
If you are a developer and don't intend to run BIND locally, you can disable
the daemon by inserting
exit 1 at the top of
package still needs to be installed for tests though.
You may also need to install
python-django-piston, but installing it seems
to cause import errors for
oauth when running the test suite.
All other development dependencies are pulled automatically from
buildout runs. (
buildout will be
automatically configured to create a cache, in order to improve build times.
To run the whole suite:
To run tests at a lower level of granularity:
./bin/test.region src/maasserver/tests/test_api.py ./bin/test.region src/maasserver/tests/test_api.py:AnonymousEnlistmentAPITest
The test runner is nose, so you
can pass in options like
--nocapture (short option:
-s). The latter is essential when using
pdb so that stdout is not
Note: When running
make test through ssh from a machine with locales that are not set up on the machine that runs the tests, some tests will fail with a
MismatchError and an "unsupported locale setting" message. Running
locale-gen for the missing locales or changing your locales on your workstation to ones present on the server will solve the issue.
is the default browser but any browser supported by Selenium can be used to
run the tests. Note that you might need to download the appropriate driver and
make it available in the path. You can then choose which browsers to use by
setting the environment variable
MAAS_TEST_BROWSERS to a comma-separated
list of the names of the browsers to use. For instance, to run the tests with
Firefox and Chrome:
export MAAS_TEST_BROWSERS="Firefox, Chrome"
Access to the database is configured in
Makefile or the test suite sets up a development database cluster inside
your branch. It lives in the
db directory, which gets created on demand.
You'll want to shut it down before deleting a branch; see below.
First, set up the project. This fetches all the required dependencies and sets
up some useful commands in
Create the database cluster and initialise the development database:
Optionally, populate your database with the sample data:
By default, the snippet
maas_proxy includes a definition for an http proxy
running on port 8000 on the same host as the MAAS server. This means you can
sudo apt-get install squid-deb-proxy
or you can edit
contrib/snippets_v2/generic to remove the proxy
Set the iSCSI config to include the MAAS configs:
sudo tee -a /etc/tgt/targets.conf < contrib/tgt.conf
The http_proxy variable is only needed if you're downloading through a proxy; "sudo" wouldn't pass it on to the script without the assignment. Or if you don't have it set but do want to download through a proxy, pass your proxy's URL: "http_proxy=http://proxy.example.com/"
Run the development webserver and watch all the logs go by:
Point your browser to http://localhost:5240/MAAS/
If you've populated your instance with the sample data, you can login as a simple user using the test account (username: 'test', password: 'test') or the admin account (username: 'admin', password: 'test').
At this point you may also want to download PXE boot resources.
To shut down the database cluster and clean up all other generated files in your branch:
To use PXE booting, each cluster controller needs to download several files relating to PXE booting. This process is automated, but it does not start by default.
First create a superuser and start all MAAS services:
bin/maas-region-admin createadmin make run
Substitute your own email. The command will prompt for a choice of password.
Next, get the superuser's API key on the account preferences page in the web UI, and use it to log into MAAS at the command-line:
bin/maas login dev http://localhost:5240/MAAS/
Start downloading PXE boot resources:
bin/maas dev node-groups import-boot-images
This sends jobs to each cluster controller, asking each to download the boot resources they require. This may download dozens or hundreds of megabytes, so it may take a while. To save bandwidth, set an HTTP proxy beforehand:
bin/maas dev maas set-config name=http_proxy value=http://...
You will need to run the built-in TFTP server on the real TFTP port (69) if you want to boot some real hardware. By default, it's set to start up on port 5244 for testing purposes. Make these changes:
bin/maas-provisionto change the tftp-port setting to 69
- Install the
sudo apt-get install authbind
- Create a file
/etc/authbind/byport/69that is executable by the user running MAAS.
sudo touch /etc/authbind/byport/69 sudo chmod a+x /etc/authbind/byport/69
Now when starting up the MAAS development webserver, "make run" and "make start" will detect authbind's presence and use it automatically.
There's a BIND daemon that is started up as part of the development service
but it runs on port 5246 by default. If you want to make it run as a real DNS
server on the box then edit
services/dns/run and change the port declaration
there so it says:
Then as for TFTP above, create an authbind authorisation:
sudo touch /etc/authbind/byport/53 sudo chmod a+x /etc/authbind/byport/53
and run as normal.
The cluster also needs authbind as it needs to bind a socket on UDP port 68 for DHCP probing:
sudo touch /etc/authbind/byport/68 sudo chmod a+x /etc/authbind/byport/68
If you omit this, nothing else will break, but you will get an error in the cluster log because it can't bind to the port.
MAAS requires a properly configured DHCP server so it can boot machines using PXE. MAAS can work with its own instance of the ISC DHCP server, if you install the maas-dhcp package:
sudo apt-get install maas-dhcp
If you choose to run your own ISC DHCP server, there is a bit more configuration to do. First, run this tool to generate a configuration that will work with MAAS:
maas-provision generate-dhcp-config [options]
maas-provision generate-dhcp-config -h to see the options. You will need
to provide various IP details such as the range of IP addresses to assign to
clients. You can use the generated output to configure your system's ISC DHCP
server, by inserting the configuration in the
Also, edit /etc/default/isc-dhcp-server to set the INTERFACES variable to just the network interfaces that should be serviced by this DHCP server.
Now restart dhcpd:
sudo service isc-dhcp-server restart
None of this work is needed if you let MAAS run its own DHCP server by
The development environment uses daemontools to manage the various services
that are required. These are all defined in subdirectories in
There are familiar service-like commands:
make start make status make restart make stop
The latter is a dependency of
distclean so just running
when you've finished with your branch is enough to stop everything.
Individual services can be manipulated too:
@<action> pattern works for any of the services.
There's an additional special action,
This starts all services up and tails their log files. When you're done, kill
tail (e.g. Ctrl-c), and all the services will be stopped.
However, when used with individual services:
it does something even cooler. First it shuts down the service, then it
restarts it in the foreground so you can see the logs in the console. More
importantly, it allows you to use
pdb, for example.
A note of caution: some of the services have slightly different behaviour when run in the foreground:
- regiond (the webapp service) will be run with its auto-reloading enabled.
Apparently Django needs a lot of debugging ;)
By default, the
clusterd services (when run from
the tree) start an introspection service. You can connect to these from the
terminal to get a REPL-like environment inside the running daemons.
There's a convenient script to help with this, utilities/introspect:
usage: introspect [-h] service Connect to a regiond's or clusterd's introspection service. positional arguments: service The name of a MAAS service to introspect. Choose from: clusterd, regiond, regiond2 optional arguments: -h, --help show this help message and exit
Here's an example of running
.------------------------------------------------------ | | Welcome to MAAS's Introspection Shell. | | This is the REGION. | | >>> | | ...
Bear in mind that commands are evaluated in the reactor thread. If you execute a blocking call, Twisted's reactor will freeze until that call returns. You won't even be able to interact via the introspection service because that relies upon the reactor!
Since MAAS is distributed mainly as an Ubuntu package, all runtime
dependencies should be packaged, and we should develop with the packaged
version if possible. All dependencies, from a package or not, need to be added
buildout.cfg, and the version specified in
allowed-picked-version is disabled, hence
buildout must be given precise
If it is a development-only dependency (i.e. only needed for the test suite,
or for developers' convenience), simply running
buildout like this will make
the necessary updates to
./bin/buildout -v buildout:allow-picked-versions=true
When creating a new source file, a Python module or test for example, always
start with the appropriate template from the
MAAS uses South to manage changes to the database schema.
Be sure to have a look at South's documentation before you make any change.
Once you've made a model change (i.e. a change to a file in
src/<application>/models/*.py) you have to run South's
command to create a migration file that will be stored in
Note that if you want to add a new model class you'll need to import it in
Once you've changed the code, ensure the database is running and contains the starting schema:
make services/database/@start make syncdb
then generate the migration script with:
./bin/maas-region-admin schemamigration maasserver --auto description_of_the_change
This will generate a migration module named
forget to add that file to the project with:
bzr add src/maasserver/migrations/<auto_number>_description_of_the_change.py
To apply that migration, run:
Note: In order to create or run a migration, you'll need to have the database server running. To do that, either run
make start, which will start all of the MAAS components or
make services/database/@start, which will start only the database server.
If you need to perform data migration, very much in the same way, you will
need to run South's
command. For instance, if you want to perform changes to the
./bin/maas-region-admin datamigration maasserver description_of_the_change
This will generate a migration module named
will need to edit that file and fill the
where data should be actually migrated. Again, don't forget to add that file
to the project:
bzr add src/maasserver/migrations/<auto_number>_description_of_the_change.py
Once the methods have been written, apply that migration with:
If you need to get an interactive
psql prompt, you can use
If you need to do the same thing with a version of MAAS you have installed from the package, you can use:
sudo maas-region-admin dbshell --installed
You can use the
\dt command to list the tables in the MAAS database. You can
also execute arbitrary SQL. For example::
maasdb=# select system_id, hostname from maasserver_node; system_id | hostname -------------------------------------------+-------------------- node-709703ec-c304-11e4-804c-00163e32e5b5 | gross-debt.local node-7069401a-c304-11e4-a64e-00163e32e5b5 | round-attack.local (2 rows)
Use the Bazaar Copyright Updater:
bzr branch lp:bzr-update-copyright ~/.bazaar/plugins/update_copyright make copyright
Then commit any changes.