npm i --save serverless-cf-vars
Add it to your serverless.yml
plugins list:
plugins:
- serverless-cf-vars
Whenever you want the cloudformation template to have a string that contains ${}
, simply use #{}
instead, and it will get transformed into correct ${}
(with Fn::Sub
inserted for you) in the cloudformation template before deployment.
If you want to make use of Fn::Sub
with mapping you need to insert the Fn::Sub
yourself and the plugin will just convert #{}
into ${}
.
resources:
Resources:
myApiIdentityPool:
Type: "AWS::Cognito::IdentityPool"
Properties:
IdentityPoolName:
Fn::Sub:
- "my#{thing}IdentityPool${self:custom.stage}"
- thing: Api
AllowUnauthenticatedIdentities: True
cognitoUnauthRole:
Type: 'AWS::IAM::Role'
Properties:
RoleName: Cognito_#{myApiIdentityPool.Name}_Unauth_Role
AssumeRolePolicyDocument:
Statement:
- Effect: Allow
Principal:
Federated: cognito-identity.amazonaws.com
Action: [ 'sts:AssumeRole' ]
Policies:
- PolicyName: cognitounauth
PolicyDocument:
Statement:
- Effect: Allow
Action:
- mobileanalytics:PutEvents
- cognito-sync:*
Resource:
- "*"
- PolicyName: CustomPermissions
PolicyDocument:
Statement:
- Effect: Allow
Action:
- lambda:Invoke
Resource:
- "arn:aws:lambda:#{AWS::Region}:#{AWS::AccountId}:function:${self:service}-${self:custom.stage}-myFunction"
Becomes
resources:
Resources:
myApiIdentityPool:
Type: "AWS::Cognito::IdentityPool"
Properties:
IdentityPoolName: myApiIdentityPoolmyStage
AllowUnauthenticatedIdentities: True
cognitoUnauthRole:
Type: 'AWS::IAM::Role'
Properties:
RoleName:
Fn::Sub: Cognito_${myApiIdentityPool.Name}_Unauth_Role
AssumeRolePolicyDocument:
Statement:
- Effect: Allow
Principal:
Federated: cognito-identity.amazonaws.com
Action: [ 'sts:AssumeRole' ]
Policies:
- PolicyName: cognitounauth
PolicyDocument:
Statement:
- Effect: Allow
Action:
- mobileanalytics:PutEvents
- cognito-sync:*
Resource:
- "*"
- PolicyName: CustomPermissions
PolicyDocument:
Statement:
- Effect: Allow
Action:
- lambda:Invoke
Resource:
- Fn::Sub:
"arn:aws:lambda:${AWS::Region}:${AWS::AccountId}:function:myService-myStage-myFunction"
Inspired by serverless-pseudo-parameters, this plugin allows you to use Cloudformation pseudo parameters, as well as substitute in other variables.
Because the same syntax is used for variables in both serverless.yml
and in cloudformation templates, there's currently no way to use variables in the generated cloudformation template. This plugin works around that by transforming #{}
into ${}
after serverless has taken care of all its variable substitutions.
Now allows you to use Fn::Sub
manually, which means you can make use of the mapping functionality.
Initial release
Released under the Copyfree Open Innovation License.