A CloudFormation Macro that converts a JSON to a string.
DEPRECATED: AWS::LanguageExtensions transform provides same function.
Please use Fn::ToJsonString intrinsic function instead of cfn-json-string-macro.
Some AWS CloudFormation properties need to be specified the JSON as text. For example, LifecyclePolicyText of Amazon Elastic Container Registry Repository LifecyclePolicy is a JSON, but we need to specify it as text.
AWSTemplateFormatVersion: 2010-09-09
Resources:
Repository:
Type: AWS::ECR::Repository
Properties:
RepositoryName: awesome-application
# a policy that expires untagged images older than 14 day
LifecyclePolicy:
LifecyclePolicyText: |
{
"rules": [
{
"rulePriority": 1,
"description": "Expire images older than 14 days",
"selection": {
"tagStatus": "untagged",
"countType": "sinceImagePushed",
"countUnit": "days",
"countNumber": 14
},
"action": {
"type": "expire"
}
}
]
}It may break syntax check and highlighting of editors.
AWSTemplateFormatVersion: 2010-09-09
Transform: JSONString
Resources:
# a policy that expires untagged images older than 14 day
LifecyclePolicy:
Type: JSON::String
Properties:
Value:
rules:
- rulePriority: 1 # now we can add comments in a policy!
description: Expire images older than 14 days
selection:
tagStatus: untagged
countType: sinceImagePushed
countUnit: days
countNumber: 14
action:
type: expire
Repository:
Type: AWS::ECR::Repository
Properties:
RepositoryName: awesome-application
LifecyclePolicy:
LifecyclePolicyText: !GetAtt LifecyclePolicy.ValueDEPRECATED: I recommend you to migrate to Fn::ToJsonString.
It is officially supported by AWS.
AWSTemplateFormatVersion: 2010-09-09
Transform: AWS::LanguageExtensions
Resources:
LifecyclePolicy:
Type: JSON::String
Properties:
Value:
Repository:
Type: AWS::ECR::Repository
Properties:
RepositoryName: awesome-application
LifecyclePolicy:
LifecyclePolicyText:
# a policy that expires untagged images older than 14 day
Fn::ToJsonString:
rules:
- rulePriority: 1 # now we can add comments in a policy!
description: Expire images older than 14 days
selection:
tagStatus: untagged
countType: sinceImagePushed
countUnit: days
countNumber: 14
action:
type: expirecfn-json-string-macro is available on AWS Serverless Application Repository. Deploy on AWS Management Console, or use the following AWS SAM (AWS Serverless Application Model) snippet.
cfnjsonstringmacro:
Type: AWS::Serverless::Application
Properties:
Location:
ApplicationId: arn:aws:serverlessrepo:us-east-1:445285296882:applications/cfn-json-string-macro
SemanticVersion: 0.0.8
Parameters:
# The name of the cloudformation macro.
MacroName: "JSONString"
# The function name that handles cloudformation macros.
# If it is empty, the name is auto generated.
MacroFunctionName: ""
# the function name that handles cloudformation custom resources.
# If it is empty, the name is auto generated.
ResourceFunctionName: ""AWSTemplateFormatVersion: 2010-09-09
Transform: JSONString # add "JSONString" to the Transform section
Resources:
JSON:
Type: JSON::String # specify "JSON::String"
Properties:
Value:
AccountId: !Ref AWS::AccountId
Region: !Ref AWS::Region
StackId: !Ref AWS::StackId
Outputs:
JSON:
# Get JSON string as an attribute
Value: !GetAtt JSON.Valueaws cloudformation deploy --template-file example.yaml --stack-name json-macro-example CAPABILITY_AUTO_EXPANDClone the repository, package the sources, and deploy.
git clone git@github.com:shogo82148/cfn-json-string-macro.git
cd cfn-json-string-macro
make all
aws cloudformation package --template-file template.yml --s3-bucket $YOUR_BUCKET_NAME --output-template-file packaged.yaml
aws cloudformation deploy --template-file packaged.yaml --stack-name json-macro --capabilities CAPABILITY_IAM CAPABILITY_AUTO_EXPANDPre-built Packages are available on https://shogo82148-cloudformation-template-$REGION.s3.$REGION.amazonaws.com/cfn-json.string-macro/latest.yaml,
You can deploy cfn-json-string-macro the template directly.
# deploy the latest version
aws cloudformation create-stack \
--template-url https://shogo82148-cloudformation-template-$REGION.s3.$REGION.amazonaws.com/cfn-json.string-macro/latest.yaml \
--stack-name json-macro \
--capabilities CAPABILITY_IAM CAPABILITY_AUTO_EXPAND
# deploy the specific version
aws cloudformation create-stack \
--template-url https://shogo82148-cloudformation-template-$REGION.s3.$REGION.amazonaws.com/cfn-json.string-macro/v0.0.8.yaml \
--stack-name json-macro \
--capabilities CAPABILITY_IAM CAPABILITY_AUTO_EXPAND
# deploy v0.0.x
aws cloudformation create-stack \
--template-url https://shogo82148-cloudformation-template-$REGION.s3.$REGION.amazonaws.com/cfn-json.string-macro/v0.0.yaml \
--stack-name json-macro \
--capabilities CAPABILITY_IAM CAPABILITY_AUTO_EXPAND
# deploy v0.x.x
aws cloudformation create-stack \
--template-url https://shogo82148-cloudformation-template-$REGION.s3.$REGION.amazonaws.com/cfn-json.string-macro/v0.yaml \
--stack-name json-macro \
--capabilities CAPABILITY_IAM CAPABILITY_AUTO_EXPAND