AWS + Cloudformation + Elasticbeanstalk - amazon-web-services

Question

When I do a create stack with the following cloudformation template using the input parameter EnvironmentType "dev", it creates the ebs application, creates the environment inside the application and deploys the sample-app.war file from the S3 bucket.
Then I am doing an update stack using the same template with an input parameter EnvironmentType "stage", this time it removes the existing dev environment and creates the stage environment inside the application.
I also tried to create stack again using the sample template entering sample application name created in the first step and this time it shows application already exist.
My requirement is to retain the dev environment and stage environment to get created inside the sample application using cloudformation.
Any suggestions, please..
---
AWSTemplateFormatVersion: 2010-09-09
Description: 'Create an ElasticBeanstalk Application, Environment and deploy the war file from S3 bucket'
Metadata:
AWS::CloudFormation::Interface:
ParameterGroups:
-
Label:
default: 'EBS Application Configuration'
Parameters:
- ApplicationName
- ApplicationDescription
- ApplicationVersion
-
Label:
default: 'EBS Environment Configuration'
Parameters:
- EnvironmentName
- EnvironmentType
- EnvironmentDescription
- EnvironmentCName
- MinInstances
- MaxInstances
Mappings:
PropertiesMap:
IntanceType:
dev: 'SingleInstance'
qa: 'SingleInstance'
stage: 'LoadBalanced'
prod: 'LoadBalanced'
Parameters:
ApplicationName:
Type: String
Description: 'Name of the ElasticBeanstalk Application'
ApplicationDescription:
Type: String
Description: 'ElasticBeanstalk Application Description'
ApplicationVersion:
Type: String
Description: 'Application version description'
EnvironmentName:
Type: String
Description: 'Name of the Environment'
AllowedPattern: '^([A-Za-z]|[0-9]|-)+$'
EnvironmentType:
Type: String
Description: 'Type of the Environment (dev, qa, stage, prod)'
AllowedValues:
- 'dev'
- 'qa'
- 'stage'
- 'prod'
EnvironmentCName:
Type: String
Description: 'CName Prefix for the ElasticBeanstalk environment'
AllowedPattern: '^([A-Za-z]|[0-9]|-)+$'
EnvironmentDescription:
Type: String
Description: 'Description of the ElasticBeanstalk environment'
MinInstances:
Type: Number
Description: 'Minimum load balanced instances (Mandatory for stage/prod)'
Default: 2
MinValue: 2
MaxValue: 10
MaxInstances:
Type: Number
Description: 'Maximum load balanced instances (Mandatory for stage/prod)'
Default: 2
MinValue: 2
MaxValue: 10
Conditions:
IsStageOrProdEnvironment:
!Or [!Equals [stage, !Ref EnvironmentType], !Equals [prod, !Ref EnvironmentType]]
Resources:
EBSApplication:
Type: AWS::ElasticBeanstalk::Application
Properties:
ApplicationName: !Ref ApplicationName
Description: !Ref ApplicationDescription
EBSApplicationVersion:
Type: AWS::ElasticBeanstalk::ApplicationVersion
Properties:
ApplicationName: !Ref EBSApplication
Description: !Ref ApplicationVersion
SourceBundle:
S3Bucket: deployable
S3Key: artifacts/sample-app.war
EBSApplicationConfigurationTemplate:
Type: AWS::ElasticBeanstalk::ConfigurationTemplate
Properties:
ApplicationName: !Ref EBSApplication
Description: 'ElasticBeanstalk Configuration Template'
SolutionStackName: '64bit Amazon Linux 2018.03 v3.0.2 running Tomcat 8.5 Java 8'
OptionSettings:
- Namespace: aws:elasticbeanstalk:environment
OptionName: EnvironmentType
Value: !FindInMap [PropertiesMap, IntanceType, !Ref EnvironmentType]
- Namespace: aws:autoscaling:asg
OptionName: MinSize
Value: !If [IsStageOrProdEnvironment, !Ref MinInstances, !Ref 'AWS::NoValue']
- Namespace: aws:autoscaling:asg
OptionName: MaxSize
Value: !If [IsStageOrProdEnvironment, !Ref MaxInstances, !Ref 'AWS::NoValue']
EBSEnvironment:
Type: AWS::ElasticBeanstalk::Environment
Properties:
ApplicationName: !Ref EBSApplication
CNAMEPrefix: !Ref EnvironmentCName
Description: !Ref EnvironmentDescription
EnvironmentName: !Ref EnvironmentName
TemplateName: !Ref EBSApplicationConfigurationTemplate
VersionLabel: !Ref EBSApplicationVersion
Outputs:
ApplicationURL:
Description: 'ElasticBeanstalk environment endpoint'
Value: !Join
- ''
- - 'http://'
- !GetAtt EBSEnvironment.EndpointURL