collective.hostout 1.0a1

What does it do?
****************

If you are new to remote application management, hostout can help you to
deploy your first site in minutes. Hostout is compatible with Plone, django, or any other
buildout based environment.

Hostout is a zc.buildout recipe_
Hostout generates a script which logs into your remote host(s) and performs preset and customizable commands. e.g.

$ bin/hostout productionserver deploy

$ bin/hostout server1 server2 supervisorctl restart instance1

$ bin/hostout all cmd ls -al

$ bin/hostout staging mylocalfabriccommand

How does it do that?
********************

Commands can easily be added from a local fabric_ script, hostout command plugins or just the
builtin commands to help you bootstrap and deploy your buildout to remote hosts.

Why is hostout awesome?
***********************
Managing multiple environments can be a real pain and a barrier to development.
Hostout puts all of the settings for all of your environments in an easy-to-manage format.

.. _recipe: http://pypi.python.org/pypi/zc.buildout#recipes
.. _fabric: http://fabfile.org

.. contents::




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

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

Add the collective.hostout part to your 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:
bootstrap : Install python and users needed to run buildout
buildout : Run the buildout on the remote server
deploy : predeploy, uploadeggs, uploadbuildout, buildout and then postdeploy
postdeploy : Perform any final plugin tasks
predeploy : Install buildout and its dependencies if needed. Hookpoint for plugins
setowners : 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 : Upload buildout pinned to local picked versions + uploaded eggs
uploadeggs : Any develop eggs are released as eggs and uploaded to the server
<BLANKLINE>


>>> 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.

Definitions
***********

buildout
zc.buildout is a tool for creating an isolated environment for running applications. It is controlled
by a configuration file(s) called a buidout file.

buildout recipe
A buildout file consists of parts each of which has a recipe which is in charge of installing a particular
piece of softare.

deploy
Take a an application you are developing and move it to a host server for use. Often deployment will be
to a staging location for limited use in testing or production for mainstream use. Production, staging
and development often have different but related to buildouts and could involve different numbers of hosts
for each.

host
In the context of this document this a machine or VPS running linux which you would like to deploy your
application to.

fabric file
see fabric_

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 linux 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 rackspacecloud or amazon EC2.

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 "all your hosts are belong to us!!!"
...
... """)

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

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

Hostout will record the versions of eggs in a local file

>>> print open('hostoutversions.cfg').read()
[versions]
collective.hostout = 0.9.4
<BLANKLINE>
# Required by collective.hostout 0.9.4
Fabric = ...


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

The buildout file used on the host pins pins the uploaded eggs

>>> print open('host1.cfg').read()
[buildout]
develop =
eggs-directory = /var/lib/plone/buildout-cache/eggs
versions = versions
newest = true
extends = buildout.cfg hostoutversions.cfg
download-cache = /var/lib/plone/buildout-cache/downloads
<BLANKLINE>
[versions]
example = 0.0.0dev-...


Bootstrapping
-------------

Hostout has a builtin bootstrap command that is called if the predeploy command doesn't find buildout
installed at the remote path.
Bootstrap not only installs buildout but
also installs the correct version of python, development tools, needed libraries and creates users needed to
manage the buildout. The buildin bootstrap may not work for all versions of linux so look
for hostout plugins that match the distribution of linux you installed.

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 these commands fail they 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 these commands fail they 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

python-version
The version of python to install during bootstrapping. Defaults to version
used in the local buildout. (UNIMPLIMENTED)


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.

see hostout.cloud_, hostout.supervisor_, hostout.ubuntu_ or
hostout.mrdeveloper_ for examples.


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

Hostout uses fabric files. Fabric is any easy way to write python that
colls commands on a host over ssh. You can create your own fabric files as follows:


>>> 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.
Uninstalling example.
Uninstalling _mr.developer.
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.



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.
Installing hostout.
Installing staging.
Installing prod.

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

Using hostout with a python2.4 buildout
***************************************

Hostout itself requires python2.6. However it is possible to use hostout with
a buildout that requires python 2.4 by using buildout's support for different
python interpretters.

>>> write('buildout.cfg',
... """
... [buildout]
... parts = host1
...
... [host1]
... recipe = collective.hostout
... host = 127.0.0.1:10022
... python = python26
...
... [python26]
... executalble = /path/to/your/python2.6/binary
...
... """ )

or alternatively if you don't want to use your local python you can get buildoit to
build it for you.


>>> write('buildout.cfg',
... """
... [buildout]
... parts = host1
...
... [host1]
... recipe = collective.hostout
... host = 127.0.0.1:10022
... python = python26
...
... [python26]
... recipe = zc.recipe.cmmi
... url = http://www.python.org/ftp/python/2.6.1/Python-2.6.1.tgz
... executable = ${buildout:directory}/parts/python/bin/python2.6
... extra_options=
... --enable-unicode=ucs4
... --with-threads
... --with-readline
...
... """ )




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
*********

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

- 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.

- 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)
------------------
- commandline changed to allow multsite and arguments
- mr.developer plugin
- supervisor plugin
- documentation clearer and more details
- ssh tests now working
- 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.