fabric

"Fabric is a simple pythonic remote deployment tool."

Less general tool - remote deployment scripting. Similar in function to capistrano. First released Jan 2008, pretty stable pre-1.0 app, Python 2.5 on unix only.

Developed by Jeff Forcier and Christian Hansen

Homepage: http://www.nongnu.org/fab/

Fail

Sad truth of web development - deployment strategy in the past frequently consisted of

• manually ftp'ing files,
• manually updating database schema
• manually restarting services to reflect configuration changes
• manually ...

Alternatives to ws_ftp

Remote deployment tool should

• run local commands
• transfer files
• run remote commands

Fabric is a framework for building a command line tool that easily accomplishes these tasks.

Usage

Create file fabfile.py. Functions in fabfile.py become fab commands accessed like:

$ fab function_name

Fabric offers a dozen built in operations - I primarily use

• put - upload files to remote hosts
• local - run local shell commands
• run - run shell command on remote host

Configuration

Configuration class supporting keyword arguments or attribute assignment. Fabric expects:

• fab_hosts: a list of remote hosts
• and optionally fab_user (if the remote username != local username)
• and that's it.

Simple Example

config(fab_hosts=['simeonfranklin.com'],
       fab_user='simeon')

def build():
    """Build local resources"""
    local("ls -l > build.txt")

def deploy():
    """Copy local resources to remote host"""
    put("build.txt","public_html/")

Simple Usage

$ fab list
Fabric v. 0.1.0.
Running list...
Available commands are:
   about  : Display Fabric version...
   *build  : Build local resources
   *deploy : Copy local resources to remote host
   help   : Display Fabric usage help...
   let    : Set a Fabric variable.
   list   : Display a list of commands ...
   shell  : Start an interactive shell ...
Done.

Simple Usage

$ fab build deploy
Running build...
[localhost] run: ls -l > build.txt
Running deploy...
Logging into the following hosts as simeon:
  simeonfranklin.com
  Password for simeon@simeonfranklin.com:
[simeonfranklin.com] put: build.txt
  -> public_html/build.txt
Done.

Requires decorator

def staging():
    config.target = "test"

def production():
    config.target = "public_html"

@requires('target',
  used_for='finding the target deployment dir.',
  provided_by=['staging', 'production'])
def deploy():
    """Copy local resources to remote host"""
    put("build.txt","$(target)/")

Output

$ fab deploy
Fabric v. 0.1.0.
Running deploy...
The 'deploy' command requires a 'target' variable.
This variable is used for finding the target
deployment dir.
Get the variable by running one of these commands:
        staging
        production
$ fab staging deploy

And Much Much More

If you need it! My personal fabfile has about a dozen commands to package my virtualenv and project, transer to the remote server, run a test suite, and restart the appropriate services. 108 lines, docstrings included.

All based on commands/decorators shown so far - and there are only about 5 decorators and a dozen operations in the fabric api all told...

Not just deployment! Great place to store frequently run utility commands (cleaning local cache, #backup# files, etc).

Conclusion

Useful, minimal, easy to learn...

This is the end

[insert public domain pic of Jim Morrison here]

My only friend, the end...

Questions?