Parsing template fails due to unsupported type: map[interface {}]interface {}

[bottemav]

Sam local is unable to parse following template.

AWSTemplateFormatVersion: '2010-09-09'
Transform: 'AWS::Serverless-2016-10-31'

Resources:
  StateMachine:
    Type: "AWS::StepFunctions::StateMachine"
    Properties:
      StateMachineName: "SamStateMachine"
      RoleArn: !Sub "arn:aws:iam::${AWS::AccountId}:role/StateMachineServiceRole"
      DefinitionString:
        !Sub
          - |-
             {
               "Comment": "${application}",
               "StartAt": "HelloWorld",
               "States": {
                 "HelloWorld": {
                   "Type": "Pass",
                   "Result": {
                       "x-datum": 0.381018,
                       "y-datum": 622.2269926397355
                     },
                   "ResultPath": "$.coords",
                   "End": true
                 }
               }
             }
          - {
            application: "applicationName"
          }

When I execute sam validate the following error is thrown
invalid YAML template: json: unsupported type: map[interface {}]interface {}.
I'm running sam local 0.2.7 on Windows 10.

[bgrindy]

I'm dealing with this issue too, same as #135

[sbuzonas]

It looks like you have your !Sub in the wrong place. It should be in front of a string, not a sequence.

[bottemav]

@sbuzonas You can use a sequence. The first is your string containing parameters and the second specifying the values of these parameters. See Intrinsic Function Reference » Fn::Sub

@bgrindy Replacing !Sub with Fn::Sub: is indeed a workaround.

I don't want to close this issue as SAM Local should support !Sub too.

[jfuss]

The validate command was integrated with SAM so this should not be an issue any longer.

Closing as this is fixed in 0.3.0