Debug CloudFormation validation issue - validation

Question

I am using a linter and my template appears valid, yet my deployment is failing with a "AWS::ElasticLoadBalancingV2::ListenerRule Validation exception". There does not appear to be any place to further drill down on this exception in the Cloud Formation console. How do I determine why my deployment is invalid?
Cloud Formation template
Parameters:
Env:
Type: String
Mappings:
EnvMap:
sandbox:
...
Resources:
HttpsListener:
Type: AWS::ElasticLoadBalancingV2::Listener
Properties:
Certificates:
- CertificateArn: !FindInMap [EnvMap, !Ref Env, CertificateArn]
DefaultActions:
- Type: forward
ForwardConfig:
# TODO: read all this stuff off HTTP listener
TargetGroupStickinessConfig:
Enabled: false
TargetGroups:
- TargetGroupArn:
!FindInMap [EnvMap, !Ref Env, LoadBalancerDefaultTargetArn]
Weight: 1
TargetGroupArn:
!FindInMap [EnvMap, !Ref Env, LoadBalancerDefaultTargetArn]
LoadBalancerArn: !FindInMap [EnvMap, !Ref Env, LoadBalancerArn]
Port: 443
Protocol: HTTPS
HttpsListenerRule:
Type: AWS::ElasticLoadBalancingV2::ListenerRule
Properties:
Actions:
- Type: forward
ForwardConfig:
TargetGroupStickinessConfig:
Enabled: false
TargetGroups:
- TargetGroupArn:
!FindInMap [EnvMap, !Ref Env, LoadBalancerRouteTargetArn]
Weight: 1
TargetGroupArn:
!FindInMap [EnvMap, !Ref Env, LoadBalancerRouteTargetArn]
Conditions:
- Field: path-pattern
PathPatternConfig:
Values:
- /*
Values:
- /*
ListenerArn: !Ref HttpsListener
Priority: 50000
Error
"Status Reason" from the event.
Resource handler returned message: "Invalid request provided: AWS::ElasticLoadBalancingV2::ListenerRule Validation exception" (RequestToken: 16bd4239-0d41-b16f-2963-b0a774009dfd, HandlerErrorCode: InvalidRequest)

Answer 1

Try to remove PathConfigPattern from the Conditions key:
HttpsListenerRule:
Type: AWS::ElasticLoadBalancingV2::ListenerRule
Properties:
Actions:
- Type: "forward"
ForwardConfig:
TargetGroupStickinessConfig:
Enabled: false
TargetGroups:
- TargetGroupArn: !FindInMap [ EnvMap, !Ref Env, LoadBalancerRouteTargetArn ]
Weight: 1
TargetGroupArn: !FindInMap [ EnvMap, !Ref Env, LoadBalancerRouteTargetArn ]
Order: 1
Conditions:
- Field: path-pattern
Values:
- "/*"
ListenerArn: !Ref HttpsListener
Priority: 50000
Also, make sure your EnvMap map looks like this:
Parameters:
Env:
Type: String
Default: sandbox
Mappings:
EnvMap:
sandbox:
LoadBalancerRouteTargetArn: "arn:aws:elasticloadbalancing:eu-west-1:111111111111:targetgroup/my-tg-1/222222222222"
prod:
LoadBalancerRouteTargetArn: "arn:aws:elasticloadbalancing:eu-west-1:333333333333:targetgroup/my-tg-2/444444444444"