"Athena.InvalidRequestException" in Step function - python-3.x

Question

I'm trying to read the query string from input but step function gives - "Athena.InvalidRequestException"
{
"StartAt": "CallFunction",
"States": {
"CallFunction": {
"Type": "Task",
"Resource": "arn:aws:lambda:us-west-2:12345:function:readFile",
"ResultPath": "$.query",
"Next": "Start an Athena query"
},
"Start an Athena query": {
"Resource": "arn:aws:states:::athena:startQueryExecution.sync",
"Parameters": {
"QueryString": "$.query",
"WorkGroup": "primary",
"ResultConfiguration": {
"OutputLocation": "s3://test_athena/test1"
}
}
}
}
Intput of Start an Athena query state:
{
"Comment": "Insert your JSON here",
"query": "\"SELECT * FROM test1 LIMIT 10; \""
}
Getting the below error on Start an Athena query state :
{
"resourceType": "athena",
"resource": "startQueryExecution.sync",
"error": "Athena.InvalidRequestException",
"cause": "line 1:1: mismatched input '$'. Expecting: 'ALTER', 'ANALYZE', 'CALL', 'COMMIT', 'CREATE', 'DEALLOCATE', 'DELETE', 'DESC', 'DESCRIBE', 'DROP', 'EXECUTE', 'EXPLAIN', 'GRANT', 'INSERT', 'PREPARE', 'RESET', 'REVOKE', 'ROLLBACK', 'SET', 'SHOW', 'START', 'UNLOAD', 'UPDATE', 'USE', <query> (Service: AmazonAthena; Status Code: 400; Error Code: InvalidRequestException; Request ID: 2a99f6eb-b853-407f-b229-d309a4ca3f5c; Proxy: null)"
}
I'm new to AWS. Can someone help me out in this how to pass query object in QueryString parameter of Athena ?

Answer 1

You are missing the ".$" annotation in your QueryString key:
"QueryString.$": "$.query",
[...] The values of [your Parameter fields] can either be static values that you include in your state machine definition, or selected from either the input or the context object with a path. For key-value pairs where the value is selected using a path, the key name must end in .$.
Source: https://docs.aws.amazon.com/step-functions/latest/dg/input-output-inputpath-params.html#input-output-parameters
Also, you should add the following fields in your second state, to be explicit there:
"Type": "Task",
"End": true