Aws-cdk: TargetGroup attribute not disabling

[v-do]

The NetworkTargetGroup constructor has the proxy_protocol_v2 constructor prop. Setting this to True correctly sets the attribute to enabled. However, when explicitly disabling by setting to False the attribute is removed rather than updated.

Reproduction Steps

Enable attribute:

target_group = network_listener.add_targets(
    "TargetGroup",
    port=80,
    proxy_protocol_v2=True,
)

CloudFormation changeset:

[~] AWS::ElasticLoadBalancingV2::TargetGroup LoadBalancer/Listener/TargetGroupGroup LoadBalancerListenerTargetGroupGroup27D2B0EE
 └─ [+] TargetGroupAttributes
     └─ [{"Key":"proxy_protocol_v2.enabled","Value":"true"}]

Deploy

Disable attribute:

target_group = network_listener.add_targets(
    "TargetGroup",
    port=80,
    proxy_protocol_v2=False,
)

Actual CloudFormation changeset:

[~] AWS::ElasticLoadBalancingV2::TargetGroup LoadBalancer/Listener/TargetGroupGroup LoadBalancerListenerTargetGroupGroup27D2B0EE
 └─ [-] TargetGroupAttributes
     └─ [{"Key":"proxy_protocol_v2.enabled","Value":"true"}]

Expected

[~] AWS::ElasticLoadBalancingV2::TargetGroup LoadBalancer/Listener/TargetGroupGroup LoadBalancerListenerTargetGroupGroup27D2B0EE
 └─ [~] TargetGroupAttributes
     └─ @@ -1,6 +1,6 @@
        [ ] [
        [ ]   {
        [ ]     "Key": "proxy_protocol_v2.enabled",
        [-]     "Value": "true"
        [+]     "Value": "false"
        [ ]   }
        [ ] ]

Workaround:

target_group.set_attribute("proxy_protocol_v2.enabled", "false")

Error Log

Environment

• CLI Version : 1.13.1 (build 96cfc63)
• Framework Version: 1.12.0
• OS : 64bit Mac OS X 10.15 19A583
• Language : Python

Other

Possible fix:

diff --git a/packages/@aws-cdk/aws-elasticloadbalancingv2/lib/nlb/network-target-group.ts b/packages/@aws-cdk/aws-elasticloadbalancingv2/lib/nlb/network-target-group.ts
index 5fe5fc5a2..d5c0df41b 100644
--- a/packages/@aws-cdk/aws-elasticloadbalancingv2/lib/nlb/network-target-group.ts
+++ b/packages/@aws-cdk/aws-elasticloadbalancingv2/lib/nlb/network-target-group.ts
@@ -54,8 +54,8 @@ export class NetworkTargetGroup extends TargetGroupBase implements INetworkTarge

     this.listeners = [];

-    if (props.proxyProtocolV2) {
-      this.setAttribute('proxy_protocol_v2.enabled', 'true');
+    if (props.proxyProtocolV2 != null) {
+      this.setAttribute('proxy_protocol_v2.enabled', props.proxyProtocolV2 ? 'true' : 'false');
     }

     this.addTarget(...(props.targets || []));

---

This is :bug: Bug Report

[nmussy]

Hey @v-do,

Thanks for the detailed issue. Would you like to open a PR yourself? Your patch looks great, all you would need is to add a test for it.

Otherwise, I'd be happy to pick it up.

[v-do]

Hi @nmussy

Cool I'm happy to open a PR for this and add the test.

[nmussy]

Thanks @v-do :tada: