serverless-plugin-powertools
Variable Resolvers
For good use cases check out tests/unit/lib/configuration/variables.
Current list of provided resolvers:
castToBoolcastToIntegercastToStringcastToBoolOrContinuecastToIntegerOrContinuecastToStringOrContinuenegateBoolnegateBoolOrContinueisTruthyisFalsy
To what end?
Currently this plugin exposes the following variable resolvers that offer type casting, boolean operations, and conditional continuations.
You can use them to ensure that external values from the environment, CloudFormation outputs, and external parameter stores are cast to the appropriate value. One important use case is defining bucket sizes through the environment or an external parameter that should ideally be an integer once rendered.
Simple conditional rendering support is provided through isTruthy and isFalsy.
Example:
custom:
something: true
boolyStuff:
makeSureThisIsBooly: ${castToBool('yes')}
doTheOppositeOfFalse: ${negateBool('false')}
doTheOppositeOfSomething: ${negateBool(${self:custom.something})}
stringyStuff:
makeSureThisIsStringy: ${castToString(1234)}
integeryStuff:
makeSureThisIsInteger: ${castToInteger('300')}
continuationSupport:
ifThisIsntAnIntegerThenUseDefault: ${castToIntegerOrContinue('eggsammich'), 0}
noContinuationSupport:
ifThisIsntAnIntegerThenUseDefault: ${castToIntegerOrContinue('42'), 0}
conditionalAwesomeness:
thisOrThat: ${isTruthy('true'), 'this'}${isTruthy('false'), 'that'}
Output:
custom:
something: true
boolyStuff:
makeSureThisIsBooly: true
doTheOppositeOfFalse: true
doTheOppositeOfSomething: false
stringyStuff:
makeSureThisIsStringy: '1234'
integeryStuff:
makeSureThisIsInteger: 300
continuationSupport:
ifThisIsntAnIntegerThenUseDefault: 0
noContinuationSupport:
ifThisIsntAnIntegerThenUseDefault: 42
conditionalAwesomeness:
thisOrThat: this