Thanks for the feedback! I updated the gist accordingly.

n.b. I did some cursory testing, but I'm not using this schema myself, so no warranties, etc.

I have come up against an issue in that if you use the Action of sts:AssumeRole the schema causes failure due there being no Resource present.

e.g. from https://docs.aws.amazon.com/IAM/latest/UserGuide/id_roles_create_policy-examples.html

{
 "Version": "2012-10-17",
 "Statement": [
   {
     "Effect": "Allow",
     "Principal": {
       "Service": [
         "elasticmapreduce.amazonaws.com",
         "datapipeline.amazonaws.com"
       ]
     },
     "Action": "sts:AssumeRole"
   }
 ]
}

I've posted a gist which fixes this over at https://gist.github.com/LeePorte/16825880f7eac126555b9aa3bda1cf22

It adds in the ability to have a Service as a principal which validates against the pattern of .+.amazonaws.com$ and has some if else logic as to weather to apply

"oneOf": [
          { "required": ["Resource"] },
          { "required": ["NotResource"] }
        ]

based on if the Action is sts:AssumeRole

This is why I love open source :) :)

Hi! The schema is awesome. Wanted to mention this:

1. Principal and NotPrincipal are also mutually exclusive, so i would add:

"oneOf": [
  { "required": ["Principal"] },
  { "required": ["NotPrincipal"] }
]

2. Seems like the array of statements cant be empty, so i'd add "minLength": 1

"Statement": {
  "oneOf": [
    {
      "$ref": "#/definitions/Statement"
    },
    {
      "type": "array",
      "minLength": 1,
      "items": {
        "$ref": "#/definitions/Statement"
      }
    }
  ]
}

Thanks a lot for the schema, it saved me some time :D