InputPath, OutputPath, ResultPath
- InputPath -> the part of the original JSON payload to take to the step
- OutPutPath -> the part of the original JSON payload to return after the step is completed
- ResultPath -> here you can define a node to store the output you create in the step.
Please note "output" node is visible in the step function logs and here in the doc, but you do not have it in the function input. It means { "output": "1.05" } will be just
"1.05" in the real world.
Input for your Lambda function from Step Function is what you can find in the node "input" in the step function logs. For example: to read a file name from a S3 event you can use this:
event.detail.requestParameters.key.
{"version": "0",
"id": "8d6f9246-b781-44f8-a026-f1c1ab2c61f0",
"detail-type": "AWS API Call via CloudTrail",
"source": "aws.s3",
"account": "123456789012",
"time": "2018-09-12T00:25:10Z",
"region": "us-east-2",
"resources": [],
"detail": {
"eventVersion": "1.05",
"userIdentity": {
"type": "IAMUser",
"principalId": "AKIAIOSFODNN7EXAMPLE",
"arn": "arn:aws:iam::123456789012:user/username",
"accountId": "123456789012",
"accessKeyId": "AKIAI44QH8DHBEXAMPLE",
"userName": "username",
"sessionContext": {
"attributes": {
"creationDate": "2018-09-11T20:10:38Z",
"mfaAuthenticated": "true"
}
},
"invokedBy": "signin.amazonaws.com"
}
}
Pass Step Definition
"HelloWorld": {
"Type": "Pass",
"End": true,
"InputPath":"$.detail.eventVersion"
}
Result
{
"output": "1.05"
}
Pass Step Definition
"HelloWorld": {
"Type": "Pass",
"End": true,
"OutputPath":"$.version"
}
Result
{
"output": "0"
}
Pass Step Definition
"HelloWorld": {
"Type": "Pass",
"End": true,
"InputPath":"$.detail.eventVersion",
"ResultPath":"$.mynode"
}
Result
{ "output": {... the original payload plus...,
"mynode": "1.05" }
}