How to reuse state definition across aws state machines? - amazon-web-services

Question

I have a state machine like below. If it has 1000 messages to notify, it spreads the notifications across 15 minutes.
Now, if I have a TwoHourStateMachine with exact same state flows but with its own set of lambdas, how will I reuse the states so that I dont duplicate the definition again?
State machine:
FifteenMinuteStateMachine:
Type: "AWS::StepFunctions::StateMachine"
Properties:
StateMachineName: "FifteenMinuteStateMachine"
DefinitionString:
Fn::Sub: |-
{
"Comment": "A 15 minute state machine",
"StartAt": "Initialize",
"TimeoutSeconds": 900,
"States": {
"Initialize" : {
"Type": "Task",
"Resource": "${InitFifteenMinuteLambda.Arn}",
"TimeoutSeconds": 15,
"Retry": [ {
"ErrorEquals": [ "States.Timeout", "Lambda.Unknown" ],
"IntervalSeconds": 2,
"MaxAttempts": 3,
"BackoffRate": 2
} ],
"Catch": [{
"ErrorEquals": ["States.ALL"],
"ResultPath": "$.errorOutput",
"Next": "Update Status"
}],
"Next": "Notification Job"
},
"Notification Job" : {
"Type": "Task",
"Resource": "${NotificationFifteenMinuteLambda.Arn}",
"TimeoutSeconds": 15,
"Retry": [ {
"ErrorEquals": [ "States.Timeout", "Lambda.Unknown" ],
"IntervalSeconds": 2,
"MaxAttempts": 3,
"BackoffRate": 2
} ],
"Catch": [{
"ErrorEquals": ["States.ALL"],
"ResultPath": "$.errorOutput",
"Next": "Update Status"
}],
"Next": "All Notifications sent?"
},
"All Notifications sent?": {
"Type": "Choice",
"Choices": [
{
"Variable": "$.status",
"StringEquals": "IN_PROGRESS",
"Next": "Wait X Seconds"
},
{
"Variable": "$.status",
"StringEquals": "SUCCEEDED",
"Next": "Update Status"
}
],
"Default": "Wait X Seconds"
},
"Wait X Seconds": {
"Type": "Wait",
"SecondsPath": "$.notificationIntervalInSeconds",
"Next": "Notification Job"
},
"Update Status": {
"Type": "Task",
"Resource": "${StatusUpdateFifteenMinuteLambda.Arn}",
"TimeoutSeconds": 15,
"End": true
}
}
}
RoleArn:
Fn::GetAtt: [ StepFunctionExecutionRole, Arn ]

Answer 1

Ashok,
If you can frame the problem with 1 set of lambda functions I believe the solution is already done for you in your example. Are you required to call different lambda functions? Ideally you can reuse the same lambda function and reuse that in the definition. Unfortunately, you can not use ARN variables at runtime currently, which is what I believe you're asking for.
Hope this helps!