diff -r a2342f26c9de -r b0b56e0f8c7f dev/provisioning/modules/datacat/README.md
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+Puppet types for concatenating data via a template
+==================================================
+
+The `datacat` and `datacat_fragment` types allow you to build up a data
+structure which is rendered using a template.  This is similar to some of the
+common concatenation patterns though the intent should be clearer as it pushes
+the boilerplate down into the type.
+
+[![Build Status](https://travis-ci.org/richardc/puppet-datacat.png)](https://travis-ci.org/richardc/puppet-datacat)
+
+Sample Usage
+------------
+
+```puppet
+datacat { '/etc/nagios/objects/hostgroups.cfg':
+  template => "${module_name}/hostgroups.cfg.erb",
+}
+
+datacat_fragment { "${::fqdn} in device hostgroup":
+  target => '/etc/nagios/objects/hostgroups.cfg',
+  data   => {
+    device => [ $::fqdn ],
+  },
+}
+
+# fred.dc1.notreal has an ilo fred-ilo.dc1.notreal
+$ilo_fqdn = regsubst($::fqdn, '\.', '-ilo.')
+datacat_fragment { "${ilo_fqdn} in device hostgroup":
+  target => '/etc/nagios/objects/hostgroups.cfg',
+  data   => {
+    device => [ $ilo_fqdn ],
+  },
+}
+```
+
+And then in your `hostgroups.cfg.erb`
+
+```erb
+# hostgroups.cfg.erb
+<% @data.keys.sort.each do |hostgroup| %>
+define hostgroup {
+    name <%= hostgroup %>
+    members <%= @data[hostgroup].sort.join(',') %>
+}
+<% end %>
+```
+
+Will produce something like:
+
+```
+# /etc/nagios/objects/hostgroups.cfg
+define hostgroup {
+    name device
+    members fred.dc1.notreal,fred-ilo.dc1.notreal
+}
+```
+
+There are additional samples in a blog post I wrote to describe the approach,
+http://richardc.unixbeard.net/2013/02/puppet-concat-patterns/
+
+Types and Definitions
+---------------------
+
+## Defined Type: `datacat`
+
+Wraps the `datacat_collector` and `file` types to cover the most common
+use-case, collecting data for and templating an entire file.
+
+The `ensure` parameter defaults to `file` (an alias for `present`). `ensure`
+can be set to `absent`. In that case `datacat` will make sure the file *does
+not exist* and will not collect anything with `datacat_collector`.
+
+## Type: `datacat_collector`
+
+The `datacat_collector` type deeply merges a data hash from
+the `datacat_fragment` resources that target it.
+
+These fragments are then rendered via an erb template specified by the
+`template_body` parameter and used to update the `target_field` property
+of the related `target_resource`.
+
+Sample usage:
+
+```puppet
+datacat_collector { 'open_ports':
+  template_body   => '<%= @data["ports"].sort.join(",") %>',
+  target_resource => File_line['open_ports'],
+  target_field    => 'line',
+}
+
+datacat_fragment { 'open webserver':
+  target => 'open_ports',
+  data   => { ports => [ 80, 443 ] },
+}
+
+datacat_fragment { 'open ssh':
+  target => 'open_ports',
+  data   => { ports => [ 22 ] },
+}
+```
+
+Caveats
+-------
+
+The template is evaluated by the agent at the point of catalog evaluation,
+this means you cannot call out to puppet parser functions as you would when
+using the usual `template()` function.
+
+
+Copyright and License
+---------------------
+
+Copyright (C) 2013 Richard Clamp
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.