Hostname switching in PHP, Python, and Ruby

gistfile1.php

$localServers = array('something.dev');
$stagingServers = array('something_else.com', 'and_another.com');
if (in_array($_SERVER['HTTP_HOST'], $localServers)) {
    // Development settings
} elseif (in_array($_SERVER['HTTP_HOST'], $stagingServers)) {
    // Staging settings
} else {
    // Production settings
}

gistfile2.py

hostname = os.uname()[1].lower()
if hostname in ['something.local']:
    # Development settings
elif hostname in ['something_else.com', 'and_another.com']:
    # Staging settings
else:
    # Production settings

gistfile3.yml

# Ruby -- Use Rails

development:
  # Development settings
test:
  # Test settings
production:
  # Production settings