cloudformation Sub 函数中的“|-”是什么意思？

Question

考虑示例（来源）

  # State machine for testing Athena Runner
  AthenaRunnerTestETLOrchestrator:
    Type: "AWS::StepFunctions::StateMachine"
    Properties:
      StateMachineName: AthenaRunnerTestETLOrchestrator
      DefinitionString:
        Fn::Sub:
          - |-
            {
              "StartAt": "Configure Athena Query",
              "States": {
                "Configure Athena Query":{
                  "Type": "Pass",
                  "Result": "{ \"AthenaQueryString\" : \"SELECT * FROM ${GlueTableName} limit 10;\", \"AthenaDatabase\": \"${GlueDatabaseName}\", \"AthenaResultOutputLocation\": \"${AthenaResultOutputLocation}\", \"AthenaResultEncryptionOption\": \"${AthenaResultEncryptionOption}\"}",
                  "Next": "Execute Athena Query"
                },
                "Execute Athena Query":{
                  "Type": "Task",
                  "Resource": "${AthenaRunnerActivityArn}",
                  "End": true
                }
              }
            }
          - {
            GlueDatabaseName: !Ref MarketingAndSalesDatabaseName,
            GlueTableName: !Ref MarketingTableName,
            AthenaRunnerActivityArn: !Ref AthenaRunnerActivity,
            AthenaResultOutputLocation: !Sub "s3://${SourceDataBucketName}/athena-runner-output/",
            AthenaResultEncryptionOption: "SSE_S3"
        }
      RoleArn: !GetAtt StateExecutionRole.Arn

函数Sub应该接收参数数组：sourceand replacements，但是为什么|-在这里传递？是它yaml还是awsSub函数功能？

Answer 1

|-是一个yaml功能，表示保留换行符且末尾没有换行符的多行字符串：

如何将字符串分成多行？