Get your facts right
Paul Nasrat • #puppetcamp 2009
@nasrat • pnasrat@googlemail.com

http://www.flickr.com/photos/tentalemonkey/2401988558

clustersshf**k

if Facter.hostname[0, 5] = "tstme"
int_service_domain = "tst.example.local"
ext_service_domain = "tst.example.com"
else
int_service_domain = "example.local"
ext_service_domain = "example.com"
end

= != ==

http://www.flickr.com/photos/lifeinelgin/2533204950/

http://www.history.navy.mil/photos/pers-us/uspers-h/g-hoppr.htm

def can_connect?(ip,port,wait_sec=2)
Timeout::timeout(wait_sec) {open(ip, port)}
return true
rescue
return false
end

def can_connect?(ip,port,wait_sec=2)
Timeout::timeout(wait_sec) {open(ip, port)}
return true
rescue
return false
end

def can_connect?(ip,port,wait_sec=2
url = "http://#{ip}:#{port}/"
Timeout::timeout(wait_sec) {open(url)}
return true
rescue
return false
end

Bug #2

def can_connect?(ip,port,wait_sec=2
url = "http://#{ip}:#{port}/"
Timeout::timeout(wait_sec) {open(url)}
return true
rescue
return false
end

def can_connect?(ip,port,wait_sec=2
url = "http://#{ip}:#{port}/"
Timeout::timeout(wait_sec) {open(url)}
return true
rescue Timeout::Error
return false
rescue
return false
end

ops == code

Dev vs Ops
http://www.flickr.com/photos/cayusa/627611844

IV

http://www.flickr.com/photos/thomasthomas/274884308/

Unit Testing

“Debugging is twice as hard as writing the code in the first place.”
Brian Kernighan

[

Test-driven
development

Behaviour driven
development

£$€

Feedback
http://www.flickr.com/photos/altemark/273968506

Tools
• rspec
• rake
• git
• mocha

cd spec
rake
(in /Users/pnasrat/Development/facter/spec)
Virtual fact
- should be zone on Solaris when a zone

require File.join(File.dirname(__FILE__), '..', 'spec_helper')

describe Facter::Util::HostnameResolver do
it "should return 'foo.example.com' when hostname returns foo.example.com"
end

spec --options spec.opts unit/hostname_spec.rb
./unit/hostname_spec.rb:3: uninitialized constant
Facter::Util::HostnameResolver (NameError)

module Facter
module Util
class HostnameResolver
end
end
end
describe Facter::Util::HostnameResolver do
it "should return 'foo.example.com' when hostname returns foo.example.com"
end

Facter::Util::HostnameResolver
- should return 'foo.example.com' when querying hostname
returns foo.example.com (PENDING: Not Yet Implemented)
Pending:
Facter::Util::HostnameResolver should return
'foo.example.com' when querying hostname returns
foo.example.com (Not Yet Implemented)
./unit/hostname_spec.rb:4
Finished in 0.0019 seconds
1 example, 0 failures, 1 pending

describe Facter::Util::HostnameResolver do
it "should return 'foo.example.com' when querying hostname returns foo.example.com" do
Facter::Util::HostnameResolver.new.hostname.should == "foo.example.com"
end
end

spec --options spec.opts unit/hostname_spec.rb
Facter::Util::HostnameResolver
- should return 'foo.example.com' when querying hostname
returns foo.example.com (FAILED - 1)
1)
NoMethodError in 'Facter::Util::HostnameResolver should
return 'foo.example.com' when querying hostname returns
foo.example.com'
undefined method `hostname' for
#<Facter::Util::HostnameResolver:0x12e71f0>
./unit/hostname_spec.rb:12:
Finished in 0.002085 seconds
1 example, 1 failure

module Facter
module Util
class HostnameResolver
def hostname
end
end
end
end
describe Facter::Util::HostnameResolver do
it "should return 'foo.example.com' when querying hostname returns foo.example.com" do
Facter::Util::HostnameResolver.new.hostname.should == "foo.example.com"
end
end

'Facter::Util::HostnameResolver should return 'foo.example.com' when
querying hostname returns foo.example.com' FAILED
expected: "foo.example.com",
got: nil (using ==)
./unit/hostname_spec.rb:14:

module Facter
module Util
class HostnameResolver
def hostname
"foo.example.com"
end
end
end
end

Facter::Util::HostnameResolver
- should return 'foo.example.com' when querying hostname
returns foo.example.com
Finished in 0.001872 seconds
1 example, 0 failures

mock objects

describe Facter::Util::HostnameResolver do
it "should return 'foo.example.com' when querying hostname returns foo.example.com" do
Facter::Util::Resolution.expects(:exec).with("hostname").returns("foo.example.com")
Facter::Util::HostnameResolver.new.hostname.should == "foo.example.com"
end
end

Mocha::ExpectationError in 'Facter::Util::HostnameResolver should return
'foo.example.com' when querying hostname returns foo.example.com'
not all expectations were satisfied
unsatisfied expectations:
- expected exactly once, not yet invoked:
Facter::Util::Resolution.exec('hostname')

require 'facter/util/resolution'
module Facter
module Util
class HostnameResolver
def hostname
Facter::Util::Resolution.exec("hostname")
end
end
end
end

Questions?

Further Info
• rspec book - http://www.pragprog.com/
titles/achbd/the-rspec-book
• TDD http://www.mockobjects.com/book/
tdd-introduction.html
• IRC - #puppet #puppet-dev
• github - other peoples code