indexer-service crashes after sending introspection query to Graph Node

[tilacog]

I found this error while the indexer-service was performing an introspection query on the Graph Node:

Error: Decorated type deeper than introspection query.
    at getType (/home/tilacog/tiago/code/edge-and-node/local-network-environments/build/graphprotocol/indexer/node_modules/graphql/utilities/buildClientSchema.js:110:15)
    at getType (/home/tilacog/tiago/code/edge-and-node/local-network-environments/build/graphprotocol/indexer/node_modules/graphql/utilities/buildClientSchema.js:103:42)
    at getType (/home/tilacog/tiago/code/edge-and-node/local-network-environments/build/graphprotocol/indexer/node_modules/graphql/utilities/buildClientSchema.js:113:28)
    at buildField (/home/tilacog/tiago/code/edge-and-node/local-network-environments/build/graphprotocol/indexer/node_modules/graphql/utilities/buildClientSchema.js:302:18)
    at keyValMap (/home/tilacog/tiago/code/edge-and-node/local-network-environments/build/graphprotocol/indexer/node_modules/graphql/jsutils/keyValMap.js:29:27)
    at buildFieldDefMap (/home/tilacog/tiago/code/edge-and-node/local-network-environments/build/graphprotocol/indexer/node_modules/graphql/utilities/buildClientSchema.js:294:37)
    at fields (/home/tilacog/tiago/code/edge-and-node/local-network-environments/build/graphprotocol/indexer/node_modules/graphql/utilities/buildClientSchema.js:218:21)
    at resolveObjMapThunk (/home/tilacog/tiago/code/edge-and-node/local-network-environments/build/graphprotocol/indexer/node_modules/graphql/type/definition.js:504:40)
    at defineFieldMap (/home/tilacog/tiago/code/edge-and-node/local-network-environments/build/graphprotocol/indexer/node_modules/graphql/type/definition.js:760:20)
    at GraphQLObjectType._fields (/home/tilacog/tiago/code/edge-and-node/local-network-environments/build/graphprotocol/indexer/node_modules/graphql/type/definition.js:685:26)

git bisect revealed that commit 2d27e9b from #3185 probably introduced the bug in the Graph Node code.

The Query:

query IntrospectionQuery {
  __schema {
    queryType {
      name
    }
    mutationType {
      name
    }
    subscriptionType {
      name
    }
    types {
      ...FullType
    }
    directives {
      name
      description
      locations
      args {
        ...InputValue
      }
    }
  }
}
fragment FullType on __Type {
  kind
  name
  description
  fields(includeDeprecated: true) {
    name
    description
    args {
      ...InputValue
    }
    type {
      ...TypeRef
    }
    isDeprecated
    deprecationReason
  }
  inputFields {
    ...InputValue
  }
  interfaces {
    ...TypeRef
  }
  enumValues(includeDeprecated: true) {
    name
    description
    isDeprecated
    deprecationReason
  }
  possibleTypes {
    ...TypeRef
  }
}
fragment InputValue on __InputValue {
  name
  description
  type {
    ...TypeRef
  }
  defaultValue
}
fragment TypeRef on __Type {
  kind
  name
  ofType {
    kind
    name
    ofType {
      kind
      name
      ofType {
        kind
        name
        ofType {
          kind
          name
          ofType {
            kind
            name
            ofType {
              kind
              name
              ofType {
                kind
                name
              }
            }
          }
        }
      }
    }
  }
}

The last log entry from Graph Node before indexer-service crashed:

INFO Query timing (GraphQL), block: 0, query_time_ms: 33, variables: null, query: <as above> , query_id: f3e751f1852e62e6-7ddc7375872c8f80, subgraph_id: indexnode, component: IndexNodeServer