E3001 Missing properties raised as an error when they're not required

cfn-lint version: 0.4.2

Description of issue.

An error about missing properties is not always useful. There are resources which don’t necessarily need properties.

Please provide as much information as possible:

• Template linting issues:

    "WaitCondition": {
      "Type": "AWS::CloudFormation::WaitCondition",
      "CreationPolicy": {
        "ResourceSignal": {
          "Timeout": "PT15M",
          "Count": {
            "Ref": "TargetCapacity"
          }
        }
      }
    }

Getting E3001 Properties not defined for resource WaitCondition

• Feature request:

I’m not sure if there’s a list of resources which don’t need properties in many situations. S3 buckets and WaitCondition seem like good candidates for not raising this. AWS docs say:

Use the optional Parameters section to customize your templates. so it doesn’t sound like it needs to be provided.

[kddejong]

If the spec didn’t have required attributes Properties wouldn’t be required.

➜  cat test.yaml
---
AWSTemplateFormatVersion: "2010-09-09"
Resources:
  myBucket:
    Type: AWS::S3::Bucket
➜  cfn-lint test1.yaml
➜  echo $?
0

[cmmeyer]

Update would be to remove the requirement – this is typically how this is handled since the current spec doesn’t support complex or logic.

I’ve created #278 to track the spec update bug.