collective.hostout 0.9.3

one click deployment for buildout based applications

collective.hostout is a remote control for you application production environment.
Hostout makes it easy to connect one buildout to another via fabric scripts helping
you deploy to and manage your application one or many remote hosts.

.. contents::


Detailed Documentation
**********************


Hostout is a zc.buildout recipe. see (http://pypi.python.org/pypi/zc.buildout#recipes)
Installing hostout generates a script which logs into your remote host(s) and performs
commands. e.g.

$ bin/hostout productionserver deploy

$ bin/hostout server1 server2 supervisorctl restart instance1

$ bin/hostout all cmd ls -al

$ bin/hostout staging mylocalfabriccommand

Installing hostout
******************

First follow instructions and to get your development buildout running on your development machine you're ready.
You can add this recipe to a buildout for Plone, django or any other buildout based environment.

Add the collective.hostout part to our development buildout.

>>> write('buildout.cfg',
... """
... [buildout]
... parts = host1
...
... [host1]
... recipe = collective.hostout
... host = 127.0.0.1:10022
... user = root
... password = root
... path = /usr/local/plone/host1
... """ % globals())

If you don't include your password you will be prompted for it later.

Next rerun your buildout to install the hostout script in your buildout bin directory

>>> print system('bin/buildout -N')
Installing host1.
Generated script '/sample-buildout/bin/hostout'.

The generated script is run with a command and host(s) as arguments

>>> print system('bin/hostout')
cmdline is: bin/hostout host1 [host2...] [all] cmd1 [cmd2...] [arg1 arg2...]
Valid hosts are: host1


Each host refers to the name of a part with recipe=collective.hostout in your buildout.
Each host corresponds to a host and remote path which is the default location for commands to act on.

>>> print system('bin/hostout host1')
cmdline is: bin/hostout host1 [host2...] [all] cmd1 [cmd2...] [arg1 arg2...]
Valid commands are:
buildout : Run the buildout on the remote server
deploy
postdeploy : Perform any final plugin tasks
predeploy : Install buildout and its dependencies if needed. Hookpoint for plugins
resetpermissions : Ensure ownership and permissions are correct on buildout and cache
run : Execute cmd on remote as login user
sudo : Execute cmd on remote as root user
uploadbuildout : A special buildout is prepared referencing uploaded eggs and all other eggs pinned to the local picked versions
uploadeggs : Any develop eggs are released as eggs and uploaded to the server

>>> print system('bin/hostout host1 run pwd')
Hostout: Running command 'run' from '.../fabfile.py'
Logging into the following hosts as root:
127.0.0.1
[127.0.0.1] run: sh -c "cd /usr/local/plone/host1 && pwd"
[127.0.0.1] out: CMD RECIEVED
Done.


Adding your own commands
************************

Hostout uses fabric files (see http://docs.fabfile.org). Create a fabric file.

>>> write('fabfile.py',"""
... def echo(cmdline1):
... hostout = get('hostout')
... bin = "%s/bin" % hostout.getRemoteBuildoutPath()
... option1 = hostout.options['option1']
... run("echo '%s %s'" % (option1, cmdline1) )
... """)

Reference this file in the fabfiles option of your hostout part.

>>> write('buildout.cfg',
... """
... [buildout]
... parts = host1
...
... [host1]
... recipe = collective.hostout
... host = 127.0.0.1:10022
... fabfiles = fabfile.py
... option1 = buildout
... user = root
... password = root
...
... """ )
>>> print system('bin/buildout -N')
Uninstalling host1.
Installing host1.

>>> print system('bin/hostout host1 echo "is cool"')
Hostout: Running command 'echo' from 'fabfile.py'
Logging into the following hosts as root:
127.0.0.1
[127.0.0.1] run: echo 'buildout is cool'
[127.0.0.1] out: CMD RECIEVED
Done.



Using builtin deploy command
****************************

Often we have a buildout installed and working on a development machine and we need to get it working on
one or many hosts quickly and easily.

First you will need a host. You'll need a linux with ssh access and sudo access. VPS and cloud hosting is
now cheap and plentiful with options as low as $11USD a month. If you're not sure, pick a pay per hour
option pre-configured with Ubuntu and give it a go for example rackspace cloud.

Next you need a production buildout for your application. There are plenty available whether it be for Plone,
grok, django, BFG, pylons. Often a buildout will come in several files, one for development and one for production.
Just remember that to get the best performance you will need to understand your buildout.

For this example we've added a development egg
to our buildout as well.

>>> mkdir('example')

>>> write('example', 'example.py',
... """
... def run():
... print "example"
...
... """)

>>> write('example', 'setup.py',
... """
... from setuptools import setup
...
... setup(
... name = "example",
... entry_points = {'default': ['mkdir = mkdir:Mkdir']},
... )
... """)

>>> write('buildout.cfg',
... """
... [buildout]
... parts = example host1
... develop = example
...
... [example]
... recipe = zc.recipe.egg
... eggs = example
...
... [host1]
... recipe = collective.hostout
... host = 127.0.0.1:10022
... user = root
... password = root
...
... """ % globals())
>>> print system('bin/buildout -N')
Develop: '.../example'
Uninstalling host1.
Installing example.
Installing host1.


The deploy command will login to your host and setup a buildout environment if it doesn't exist, upload
and installs the buildout. The deploy command is actually five commands

predeploy
Bootstrap the server if needed.

uploadeggs
Any develop eggs are released as eggs and uploaded to the server

uploadbuildout
A special buildout is prepared referencing uploaded eggs and all other eggs pinned to the local picked versions

buildout
Run the buildout on the remote server

postdeploy
Perform any final plugin tasks

>>> print system('bin/hostout host1 deploy')
running clean
...
creating '...example-0.0.0dev_....egg' and adding '...' to it
...
Hostout: Running command 'predeploy' from '.../collective.hostout/collective/hostout/fabfile.py'
...
Hostout: Running command 'uploadeggs' from '.../collective.hostout/collective/hostout/fabfile.py'
Hostout: Preparing eggs for transport
Hostout: Develop egg /sample-buildout/example changed. Releasing with hash ...
Hostout: Eggs to transport:
example = 0.0.0dev-...
Hostout: Wrote versions to /sample-buildout/host1.cfg
...
Hostout: Running command 'uploadbuildout' from '.../collective.hostout/collective/hostout/fabfile.py'
...
Hostout: Running command 'buildout' from '.../collective/hostout/fabfile.py'
...
Hostout: Running command 'postdeploy' from '.../collective.hostout/collective/hostout/fabfile.py'
...


We now have a live version of our buildout deployed to our host

Deploy options
--------------

buildout
The configuration file you which to build on the remote host. Note this doesn't have
to be the same .cfg as the hostout section is in but the versions of the eggs will be determined
from the buildout with the hostout section in. Defaults to buildout.cfg

effective-user
The user which will own the buildout files. Defaults to #TODO

path
The absolute path on the remote host where the buildout will be created.
Defaults to ~${hostout:effective-user}/buildout

pre-commands
A series of shell commands executed as root before the buildout is run. You can use this
to shut down your application. If this command fails it will be ignored.

post-commands
A series of shell commands executed as root after the buildout is run. You can use this
to startup your application. If this command fails it will be ignored.

parts
Runs the buildout with a parts value equal to this

include
Additional configuration files or directories needed to run this buildout

buildout-cache
If you want to override the default location for the buildout-cache on the host



Using command plugins
*********************

You use commands others have made via the extends option.
Name a buildout recipe egg in the extends option and buildout will download
and merge any fabfiles and other configuration options from that recipe into
your current hostout configuration. The following are examples of builtin
plugins others are available on pypi.

collective.hostout:supervisor
-----------------------------
This recipe is an example of a hostout plugin. It will set pre and post commands to stop and then
restart supervisor after the deployment. It takes the following options

>>> write('buildout.cfg',
... """
... [buildout]
... parts = host1
...
... [host1]
... recipe = collective.hostout
... host = 127.0.0.1:10022
... password = root
... extends = collective.hostout:supervisor
... supervisor = supervisor
... init.d = True
...
... """)

>>> print system('bin/buildout -N')
Uninstalling host1.
Uninstalling example.
Installing host1.

>>> print system('bin/hostout host1')
cmdline is: bin/hostout host1 [host2...] [all] cmd1 [cmd2...] [arg1 arg2...]
Valid commands are:
...
installonstartup : Installs supervisor into your init.d scripts in order to ensure that supervisor is started on boot
...
supervisorctl : Takes command line arguments and runs supervisorctl on the remote host
supervisorshutdown : Shutdown the supervisor daemon
supervisorstartup : Start the supervisor daemon
...

The following options maybe used

supervisor
The name of the supervisor part to stop and restart

init.d
If set the supervisord script will be linked into init.d so any machine restart will also
start supervisor

In addition supervisor plugin will shutdown supervisor during pre-deployment and startup
supervisor during post-deployment.

>>> print system('bin/hostout host1 deploy')
Hostout: Running command 'predeploy' from '/.../collective/hostout/supervisor/fabfile.py'
Logging into the following hosts as :
127.0.0.1
[127.0.0.1] sudo: /var/lib/plone/host1/bin/supervisorctl shutdown || echo 'Failed to shutdown'
...
Hostout: Running command 'postdeploy' from '/.../collective/hostout/supervisor/fabfile.py'
...
[127.0.0.1] sudo: /var/lib/plone/host1/bin/supervisord
...
[127.0.0.1] sudo: /var/lib/plone/host1/bin/supervisorctl status
...
Hostout: Running command 'postdeploy' from '.../collective.hostout/collective/hostout/fabfile.py'
...


collective.hostout:mrdeveloper
------------------------------
if you include this extension your hostout deployment will fail if you have any uncommited modifications

>>> write('buildout.cfg',
... """
... [buildout]
... parts = host1 example
... extensions =
... mr.developer
... sources = sources
... sources-dir = .
... auto-checkout = example
... [sources]
... example = fs example
...
... [example]
... recipe = zc.recipe.egg
... eggs = example
...
... [host1]
... recipe = collective.hostout
... host = 127.0.0.1:10022
... password = root
... extends = collective.hostout:mrdeveloper
...
... """ )

>>> print system('bin/buildout -N')
mr.developer: Filesystem package 'example' doesn't need a checkout.
Develop: '/sample-buildout/./example'
Uninstalling host1.
Installing _mr.developer.
Getting distribution for 'elementtree'.
Got elementtree 1.2.6-20050316.
Generated script '/sample-buildout/bin/develop'.
Installing example.
Installing host1.


#>>> print system('bin/hostout host1 deploy')
Package 'example1' has been modified.
Hostout aborted


collective.hostout:ubuntu
-------------------------
(NOT CURRENTLY IMPLEMENTED)
if you include this extension native ubuntu packages will be used on your remote host instead
of the more generic plone unified installer.

**Warning: this will change your system packages as needed to get the correct python version**


collective.hostout.datafs
-------------------------
(NOT IMPLEMENTED)
Adding this extension will provide addition commands for manipulating the ZODB database files
of a zope or plone installation.

>>> write('buildout.cfg',
... """
... [buildout]
... parts = host1
...
... [host1]
... recipe = collective.hostout
... host = localhost:10022
... password = root
... extends = collective.hostout:datafs
... filestorage =
... ${buildout:directory}/var/filestorage/Data01.fs
... ${buildout:directory}/var/filestorage/Data02.fs
...
...
... """ % globals())

#>>> print system('bin/buildout -N')

#>>> print system('bin/hostout host1 upload')
This will overwrite the following filestorage files on your host.
- var/filestorage/Data.fs
Are you sure you want to do this [y/N]?

#>>> print system('bin/hostout host1 download')
This will overwrite the following filestorage files on your local buildout directory.
- var/filestorage/Data.fs
Are you sure you want to do this [y/N]?

#>>> print system('bin/hostout host1 backup')
Running repozo to create backup on remote server 'host1'
...

Sharing hostout options
***********************

For more complicated arrangements you can use the extends value to share defaults
between multiple hostout definitions

>>> write('buildout.cfg',
... """
... [buildout]
... parts = prod staging
...
... [hostout]
... recipe = collective.hostout
... password = blah
... user = root
... identity-file = id_dsa.pub
... pre-commands =
... ${buildout:directory}/bin/supervisorctl shutdown || echo 'Unable to shutdown'
... post-commands =
... ${buildout:directory}/bin/supervisord
... effective-user = plone
... include = config/haproxy.in
...
...
... [prod]
... recipe = collective.hostout
... extends = hostout
... host = localhost:10022
... buildout =
... config/prod.cfg
... path = /var/plone/prod
...
... [staging]
... recipe = collective.hostout
... extends = hostout
... host = staging.prod.com
... buildout =
... config/staging.cfg
... path = /var/plone/staging
...
... """ % globals())

>>> print system('bin/buildout -N')
Uninstalling host1.
Uninstalling example.
Uninstalling _mr.developer.
Installing hostout.
Installing staging.
Installing prod.

#>>> print system('bin/hostout deploy')
Invalid hostout hostouts are: prod staging



Detailed Hostout Options
************************

host
the IP or hostname of the host to deploy to. by default it will connect to port 22 using ssh.
You can override the port by using hostname:port

user
The user which hostout will attempt to login to your host as. Will read a users ssh config to get a default.

password
The password for the login user. If not given then hostout will ask each time.

identity-file
A public key for the login user.

extends
Specifies another part which contains defaults for this hostout

fabfiles
Path to fabric files that contain commands which can then be called from the hostout
script. Commands can access hostout options via hostout.options from the fabric environment.




Todo list
*********

- use latest fabbric and thus switch to python2.6

- finish ubuntu bootstrap

- plugins for database handling including backing up, moving between development, staging and production
regardless of location.

- plugins for cloud api's such as Amazon Ec2 or Rackspace Cloud

- Integrate with SCM to tag all parts so deployments can be rolled back.

- Handle basic rollback when no SCM exists, for instance when buildout fails.

- Automatically setup host with password-less ssh login.

- Help deploy DNS settings, possibly by hosting company specific plugins

- Incorporate unified installer environment setup scripts directly.

- Support firewalled servers by an optional tunnel back to a client side web proxy.

- Explore ways to make an even easier transition from default plone install to fully hosted site.

Credits
*******

Dylan Jay <software at pretaweb dot com>





Release History
***************

0.9.4 (2009-01-31)
==================
- documentation clearer and more details
- ssh tests now working
- commandline changed to allow multsite and arguments
- mr.developer plugin
- Nice listing of available commands


0.9.3
==================
- Fixed how extends works
- fabric commands have hostout in environment rather than argument
- new command to reset permissions
- fab_hosts etc is set for all commands
- supervisor recipe now uses fabfile

0.9.2 (2009-09-26)
==================
- can extend from recipe directly instead of a buildout part
- supervisor plugin recipe
- fixed version pinning for recipes


0.9.1 (2009-09-17)
==================
- fix bug in lowering case of package names in versions


0.9 (2009-09-15)
==================
- new commandline to allow deploying to multiple hosts at once
- ability to take defaults from another part using 'extends' option
- fabfiles option to create your own hostout commands
- moved hostout cfg generation to deployment time
- egg releases hash of contents as version numbers and won't be built or uploaded unless changed
- new parts option to only install specified parts
- many option names simplified (backwards compatibility maintained)
- pre-commmands now runs before buildout initialisation
- buildout now run as 'effective-user' rather than root. pre and post commands still run as root
- eggs released directly to the download cache rather than a seperate dist directory
- version recognition only done once for all hostout parts


0.1.3 (2009-05-06)
==================

- Fixed getting fabfile as a resource when packaged as an egg
- Allow for specifying extra configuration not in the buildout files

0.1.2 (2009-04-24)
==================

Initial release. Basic uploading of eggs and running of remote buildout.