feat(elbv2): add name validation for target group and load balancer names

packages/@aws-cdk/aws-elasticloadbalancingv2/lib/shared/base-load-balancer.ts

@@ -300,4 +300,27 @@ export abstract class BaseLoadBalancer extends Resource {
   public removeAttribute(key: string) {
     this.setAttribute(key, undefined);
   }
+
+  protected validate(): string[] {
+    const ret = super.validate();
+
+    // https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-elasticloadbalancingv2-loadbalancer.html#cfn-elasticloadbalancingv2-loadbalancer-name
+    const loadBalancerName = this.physicalName;
+    if (!Token.isUnresolved(loadBalancerName) && loadBalancerName !== undefined) {
+      if (loadBalancerName.length > 32) {
+        ret.push(`Load balancer name: "${loadBalancerName}" can have a maximum of 32 characters.`);
+      }
+      if (loadBalancerName.startsWith('internal-')) {
+        ret.push(`Load balancer name: "${loadBalancerName}" must not begin with "internal-".`);
+      }
+      if (loadBalancerName.startsWith('-') || loadBalancerName.endsWith('-')) {
+        ret.push(`Load balancer name: "${loadBalancerName}" must not begin or end with a hyphen.`);
+      }
+      if (!/^[0-9a-z-]+$/i.test(loadBalancerName)) {
+        ret.push(`Load balancer name: "${loadBalancerName}" must contain only alphanumeric characters or hyphens.`);
+      }
+    }
+
+    return ret;
+  }
 }

packages/@aws-cdk/aws-elasticloadbalancingv2/lib/shared/base-target-group.ts

@@ -339,6 +339,20 @@ export abstract class TargetGroupBase extends CoreConstruct implements ITargetGr
       ret.push("'vpc' is required for a non-Lambda TargetGroup");
     }
 
+    // https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-resource-elasticloadbalancingv2-targetgroup.html#cfn-elasticloadbalancingv2-targetgroup-name
+    const targetGroupName = this.resource.name;
+    if (!cdk.Token.isUnresolved(targetGroupName) && targetGroupName !== undefined) {
+      if (targetGroupName.length > 32) {
+        ret.push(`Target group name: "${targetGroupName}" can have a maximum of 32 characters.`);
+      }
+      if (targetGroupName.startsWith('-') || targetGroupName.endsWith('-')) {
+        ret.push(`Target group name: "${targetGroupName}" must not begin or end with a hyphen.`);
+      }
+      if (!/^[0-9a-z-]+$/i.test(targetGroupName)) {
+        ret.push(`Target group name: "${targetGroupName}" must contain only alphanumeric characters or hyphens.`);
+      }
+    }
+
     return ret;
   }
 }

packages/@aws-cdk/aws-elasticloadbalancingv2/test/nlb/load-balancer.test.ts

@@ -241,6 +241,96 @@ describe('tests', () => {
     });
   });
 
+  test('loadBalancerName unallowed: more than 32 characters', () => {
+    // GIVEN
+    const app = new cdk.App();
+    const stack = new cdk.Stack(app);
+    const vpc = new ec2.Vpc(stack, 'Stack');
+
+    // WHEN
+    new elbv2.NetworkLoadBalancer(stack, 'NLB', {
+      loadBalancerName: 'a'.repeat(33),
+      vpc,
+    });
+
+    // THEN
+    expect(() => {
+      app.synth();
+    }).toThrow('Load balancer name: "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa" can have a maximum of 32 characters.');
+  });
+
+  test('loadBalancerName unallowed: starts with "internal-"', () => {
+    // GIVEN
+    const app = new cdk.App();
+    const stack = new cdk.Stack(app);
+    const vpc = new ec2.Vpc(stack, 'Stack');
+
+    // WHEN
+    new elbv2.NetworkLoadBalancer(stack, 'NLB', {
+      loadBalancerName: 'internal-myLoadBalancer',
+      vpc,
+    });
+
+    // THEN
+    expect(() => {
+      app.synth();
+    }).toThrow('Load balancer name: "internal-myLoadBalancer" must not begin with "internal-".');
+  });
+
+  test('loadBalancerName unallowed: starts with hyphen', () => {
+    // GIVEN
+    const app = new cdk.App();
+    const stack = new cdk.Stack(app);
+    const vpc = new ec2.Vpc(stack, 'Stack');
+
+    // WHEN
+    new elbv2.NetworkLoadBalancer(stack, 'NLB', {
+      loadBalancerName: '-myLoadBalancer',
+      vpc,
+    });
+
+    // THEN
+    expect(() => {
+      app.synth();
+    }).toThrow('Load balancer name: "-myLoadBalancer" must not begin or end with a hyphen.');
+  });
+
+  test('loadBalancerName unallowed: ends with hyphen', () => {
+    // GIVEN
+    const app = new cdk.App();
+    const stack = new cdk.Stack(app);
+    const vpc = new ec2.Vpc(stack, 'Stack');
+
+    // WHEN
+    new elbv2.NetworkLoadBalancer(stack, 'NLB', {
+      loadBalancerName: 'myLoadBalancer-',
+      vpc,
+    });
+
+    // THEN
+    expect(() => {
+      app.synth();
+    }).toThrow('Load balancer name: "myLoadBalancer-" must not begin or end with a hyphen.');
+  });
+
+  test('loadBalancerName unallowed: unallowed characters', () => {
+    // GIVEN
+    const app = new cdk.App();
+    const stack = new cdk.Stack(app);
+    const vpc = new ec2.Vpc(stack, 'Stack');
+
+    // WHEN
+    new elbv2.NetworkLoadBalancer(stack, 'NLB', {
+      loadBalancerName: 'my load balancer',
+      vpc,
+    });
+
+    // THEN
+    expect(() => {
+      app.synth();
+    }).toThrow('Load balancer name: "my load balancer" must contain only alphanumeric characters or hyphens.');
+  });
+
   test('imported network load balancer with no vpc specified throws error when calling addTargets', () => {
     // GIVEN
     const stack = new cdk.Stack();

packages/@aws-cdk/aws-elasticloadbalancingv2/test/nlb/target-group.test.ts

@@ -144,6 +144,82 @@ describe('tests', () => {
     }).toThrow(/Health check interval '5' not supported. Must be one of the following values '10,30'./);
   });
 
+  test('targetGroupName unallowed: more than 32 characters', () => {
+    // GIVEN
+    const app = new cdk.App();
+    const stack = new cdk.Stack(app);
+    const vpc = new ec2.Vpc(stack, 'Stack');
+
+    // WHEN
+    new elbv2.NetworkTargetGroup(stack, 'Group', {
+      vpc,
+      port: 80,
+      targetGroupName: 'a'.repeat(33),
+    });
+
+    // THEN
+    expect(() => {
+      app.synth();
+    }).toThrow('Target group name: "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa" can have a maximum of 32 characters.');
+  });
+
+  test('targetGroupName unallowed: starts with hyphen', () => {
+    // GIVEN
+    const app = new cdk.App();
+    const stack = new cdk.Stack(app);
+    const vpc = new ec2.Vpc(stack, 'Stack');
+
+    // WHEN
+    new elbv2.NetworkTargetGroup(stack, 'Group', {
+      vpc,
+      port: 80,
+      targetGroupName: '-myTargetGroup',
+    });
+
+    // THEN
+    expect(() => {
+      app.synth();
+    }).toThrow('Target group name: "-myTargetGroup" must not begin or end with a hyphen.');
+  });
+
+  test('targetGroupName unallowed: ends with hyphen', () => {
+    // GIVEN
+    const app = new cdk.App();
+    const stack = new cdk.Stack(app);
+    const vpc = new ec2.Vpc(stack, 'Stack');
+
+    // WHEN
+    new elbv2.NetworkTargetGroup(stack, 'Group', {
+      vpc,
+      port: 80,
+      targetGroupName: 'myTargetGroup-',
+    });
+
+    // THEN
+    expect(() => {
+      app.synth();
+    }).toThrow('Target group name: "myTargetGroup-" must not begin or end with a hyphen.');
+  });
+
+  test('targetGroupName unallowed: unallowed characters', () => {
+    // GIVEN
+    const app = new cdk.App();
+    const stack = new cdk.Stack(app);
+    const vpc = new ec2.Vpc(stack, 'Stack');
+
+    // WHEN
+    new elbv2.NetworkTargetGroup(stack, 'Group', {
+      vpc,
+      port: 80,
+      targetGroupName: 'my target group',
+    });
+
+    // THEN
+    expect(() => {
+      app.synth();
+    }).toThrow('Target group name: "my target group" must contain only alphanumeric characters or hyphens.');
+  });
+
   test.each([elbv2.Protocol.UDP, elbv2.Protocol.TCP_UDP, elbv2.Protocol.TLS])(
     'Throws validation error, when `healthCheck` has `protocol` set to %s',
     (protocol) => {