Serverless CF Vars

Installation

``shell
yarn add --dev serverless-cf-vars
`

or

`shell
npm i --save-dev serverless-cf-vars
`

Add it to your serverless.yml plugins list:

`yaml
plugins:
- serverless-cf-vars
`

Usage

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 ${}.

Works on both Resources and Outputs.

$3

`yaml
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

`yaml
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"
`

Information

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.

Changelog

$3

- Update lodash dependency to 4.17.x
- Update license from COIL 0.5 to COIL 0.6

$3

- Update lodash dependency to 4.17.21

$3

- Update lodash dependency to 4.17.20, fixes #6

$3

- Update lodash dependency to 4.17.15, fixes #5

$3

- Update lodash dependency to 4.17.11, fixes #4

$3

- Works on both Resources and Outputs
- Fixes #2
- Added tests

$3

- Now allows you to use Fn::Sub` manually, which means you can make use of the mapping functionality.

$3

- Initial release

License

Released under the Copyfree Open Innovation License.