Module: MkStack

Defined in:

lib/mkstack.rb,
lib/mkstack/section.rb,
lib/mkstack/template.rb

Overview

Merge multiple CloudFormation template files into a single template. Each file may be in either JSON or YAML format.

Get started with template = MkStack::Template.new

ERB

By default all files are run through an ERB (Embedded RuBy) processor.

<% desc = "awesome" %>

AWSTemplateFormatVersion: "2010-09-09"
Description: My <%= desc %> CloudFormation template

It is safe to leave this enabled. If a file doesn’t have any ERB tags it is passed through untouched.

Include

MkStack searches each file for a section named Include, which should be a list of filenames. These function the same as adding the listed files on the command line.

JSON

"Include" : [
  "foo.yaml",
  "bar.json"
]

YAML

Include:
  - foo.yaml
  - bar.json

ERB and Include working together

MkStack uses a single binding for all files. This allows ERB tags defined in one file to be referenced in subsequent files.

foo.yaml

Include:
  - bar.json

<% tags_json = %q{
     "Tags": [
       { "Key" : "application", "Value" : "mkstack" }
     ]
   }
%>

bar.json

{
  "Resources" : {
    "sg": {
      "Type" : "AWS::EC2::SecurityGroup",
      "Properties" : {
        "GroupDescription" : { "Fn::Sub" : "Security Group for ${application}" }
        <%= tags_json %>
      }
    }
  }
}

Note that foo.yaml is processed before bar.json.

See Also

MkStack::Template
MkStack::Section

Defined Under Namespace

Classes: Section, Template