Create a file for each defined block with puppet - puppet

Question

I have a running manifest, where I create a folder and a file from a setting (exerpt):
define ffnord::mesh(
$mesh_if_id = "low",
$mesh_mtu_low = 1280,
$fastd_low_port = 11280, # fastd port
) {
ffnord::fastd { "fastd_${mesh_code}":
mesh_if_id => $mesh_if_id,
mesh_mtu_low => $mesh_mtu_low,
fastd_low_port => $fastd_low_port,
}
}
and
define ffnord::fastd( $mesh_if_id
, $mesh_code
, $mesh_mtu_low = 1280
, $fastd_low_port
) {
file {
"/etc/fastd/${mesh_code}-mesh-low-vpn/":
ensure =>directory,
require => Package[ffnord::resources::fastd];
"/etc/fastd/${mesh_code}-mesh-low-vpn/fastd.conf":
ensure => file,
notify => Service[ffnord::resources::fastd],
content => template('ffnord/etc/fastd/fastd-low.conf.erb');
}
}
How can I define a variable amount of those configs:
$mesh_if_id = "low",
$mesh_mtu_low = 1280,
$fastd_low_port = 11280, # fastd port
$mesh_if_id = "something",
$mesh_mtu_low = 12345,
$fastd_low_port = 112345, # fastd port
...
and loop through those blocks to create a folder and file inside ffnord/etc/fastd/ for each block automatically?
(I want to solve this problem: https://github.com/ffnord/ffnord-puppet-gateway/pull/116#issuecomment-100619610 )

Answer 1

In Puppet 3.x there is no "looping", but there are a few tricks. You can pass a Hash of data that represents N number of ffnord::fastd instances:
define define ffnord::mesh($fastd_hash) {
create_resources('ffnord::fastd', $fastd_hash)
}
define ffnord::fastd($mesh_code, $fastd_low_port, $mesh_mtu_low = 1280) {
file {
"/etc/fastd/${mesh_code}-mesh-low-vpn/":
ensure =>directory,
require => Package[ffnord::resources::fastd];
"/etc/fastd/${mesh_code}-mesh-low-vpn/fastd.conf":
ensure => file,
notify => Service[ffnord::resources::fastd],
content => template('ffnord/etc/fastd/fastd-low.conf.erb');
}
}
$hash_of_fastds = {
"low_id" => {
mesh_code => 'low,
mesh_mtu_low => 1280,
fastd_low_port => 11280,
},
"some_id" => {
mesh_code => 'something',
mesh_mtu_low => 12345,
fastd_low_port => 112345,
},
}
ffnord::mesh { 'foo': fastd_hash => $hash_of_fastds, }
Note I've modified define ffnord::fastd slightly, where you had a $mesh_if_id parameter I've turned this into the $namevar of ffnord::fastd.
The first level of $hash_of_fastds translates to the names of the ffnord::fastd instances, the second level of the hash are the parameters for each ffnord::fastd.
See the documentation on the create_resources function for more information.
In Puppet 4 you could use the each function to achieve a similar result.