Module: LonoCfn::AwsServices

Included in:
Base, Delete, Diff, Preview
Defined in:
lib/lono-cfn/aws_services.rb

Instance Method Summary collapse

Instance Method Details

#cfn ⇒ Object 



5
6
7
 
# File 'lib/lono-cfn/aws_services.rb', line 5

def cfn
  @cfn ||= Aws::CloudFormation::Client.new
end

#stack_exists?(stack_name) ⇒ Boolean

Returns:

  • (Boolean) 


9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
 
# File 'lib/lono-cfn/aws_services.rb', line 9

def stack_exists?(stack_name)
  return true if testing_update?
  return false if @options[:noop]

  exist = nil
  begin
    # When the stack does not exist an exception is raised. Example:
    # Aws::CloudFormation::Errors::ValidationError: Stack with id blah does not exist
    resp = cfn.describe_stacks(stack_name: stack_name)
    exist = true
  rescue Aws::CloudFormation::Errors::ValidationError => e
    if e.message =~ /does not exist/
      exist = false
    elsif e.message.include?("'stackName' failed to satisfy constraint")
      # Example of e.message when describe_stack with invalid stack name
      # "1 validation error detected: Value 'instance_and_route53' at 'stackName' failed to satisfy constraint: Member must satisfy regular expression pattern: [a-zA-Z][-a-zA-Z0-9]*|arn:[-a-zA-Z0-9:/._+]*"
      puts "Invalid stack name: #{stack_name}"
      puts "Full error message: #{e.message}"
      exit 1
    else
      raise # re-raise exception  because unsure what other errors can happen
    end
  end
  exist
end

#testing_update? ⇒ Boolean

Returns:

  • (Boolean) 


35
36
37
 
# File 'lib/lono-cfn/aws_services.rb', line 35

def testing_update?
  ENV['TEST'] && self.class.name == "LonoCfn::Update"
end