Set default value to elbv2 FakeTargetGroup (#1349)

tests/test_elbv2/test_elbv2.py

@@ -412,6 +412,43 @@ def test_create_target_group_and_listeners():
     response = conn.describe_target_groups()
     response.get('TargetGroups').should.have.length_of(0)
 
+@mock_elbv2
+@mock_ec2
+def test_create_target_group_without_non_required_parameters():
+    conn = boto3.client('elbv2', region_name='us-east-1')
+    ec2 = boto3.resource('ec2', region_name='us-east-1')
+
+    security_group = ec2.create_security_group(
+        GroupName='a-security-group', Description='First One')
+    vpc = ec2.create_vpc(CidrBlock='172.28.7.0/24', InstanceTenancy='default')
+    subnet1 = ec2.create_subnet(
+        VpcId=vpc.id,
+        CidrBlock='172.28.7.192/26',
+        AvailabilityZone='us-east-1a')
+    subnet2 = ec2.create_subnet(
+        VpcId=vpc.id,
+        CidrBlock='172.28.7.192/26',
+        AvailabilityZone='us-east-1b')
+
+    response = conn.create_load_balancer(
+        Name='my-lb',
+        Subnets=[subnet1.id, subnet2.id],
+        SecurityGroups=[security_group.id],
+        Scheme='internal',
+        Tags=[{'Key': 'key_name', 'Value': 'a_value'}])
+
+    # request without HealthCheckIntervalSeconds parameter
+    # which is default to 30 seconds
+    response = conn.create_target_group(
+        Name='a-target',
+        Protocol='HTTP',
+        Port=8080,
+        VpcId=vpc.id,
+        HealthCheckProtocol='HTTP',
+        HealthCheckPort='8080'
+    )
+    target_group = response.get('TargetGroups')[0]
+    target_group.should_not.be.none
 
 @mock_elbv2
 @mock_ec2