NetworkListener

class aws_cdk.aws_elasticloadbalancingv2.NetworkListener(scope, id, *, load_balancer, port, alpn_policy=None, certificates=None, default_action=None, default_target_groups=None, protocol=None, ssl_policy=None, tcp_idle_timeout=None)

Bases: BaseListener

Define a Network Listener.

Resource:

AWS::ElasticLoadBalancingV2::Listener

ExampleMetadata:

infused

Example:

# vpc: ec2.Vpc
# asg: autoscaling.AutoScalingGroup
# sg1: ec2.ISecurityGroup
# sg2: ec2.ISecurityGroup


# Create the load balancer in a VPC. 'internetFacing' is 'false'
# by default, which creates an internal load balancer.
lb = elbv2.NetworkLoadBalancer(self, "LB",
    vpc=vpc,
    internet_facing=True,
    security_groups=[sg1]
)
lb.add_security_group(sg2)

# Add a listener on a particular port.
listener = lb.add_listener("Listener",
    port=443
)

# Add targets on a particular port.
listener.add_targets("AppFleet",
    port=443,
    targets=[asg]
)
Parameters:
  • scope (Construct) –

  • id (str) –

  • load_balancer (INetworkLoadBalancer) – The load balancer to attach this listener to.

  • port (Union[int, float]) – The port on which the listener listens for requests.

  • alpn_policy (Optional[AlpnPolicy]) – Application-Layer Protocol Negotiation (ALPN) is a TLS extension that is sent on the initial TLS handshake hello messages. ALPN enables the application layer to negotiate which protocols should be used over a secure connection, such as HTTP/1 and HTTP/2. Can only be specified together with Protocol TLS. Default: - None

  • certificates (Optional[Sequence[IListenerCertificate]]) – Certificate list of ACM cert ARNs. You must provide exactly one certificate if the listener protocol is HTTPS or TLS. Default: - No certificates.

  • default_action (Optional[NetworkListenerAction]) – Default action to take for requests to this listener. This allows full control of the default Action of the load balancer, including weighted forwarding. See the NetworkListenerAction class for all options. Cannot be specified together with defaultTargetGroups. Default: - None.

  • default_target_groups (Optional[Sequence[INetworkTargetGroup]]) – Default target groups to load balance to. All target groups will be load balanced to with equal weight and without stickiness. For a more complex configuration than that, use either defaultAction or addAction(). Cannot be specified together with defaultAction. Default: - None.

  • protocol (Optional[Protocol]) – Protocol for listener, expects TCP, TLS, UDP, or TCP_UDP. Default: - TLS if certificates are provided. TCP otherwise.

  • ssl_policy (Optional[SslPolicy]) – SSL Policy. Default: - Current predefined security policy.

  • tcp_idle_timeout (Optional[Duration]) – The load balancer TCP idle timeout. Default: Duration.seconds(350)

Methods

add_action(_id, *, action)

Perform the given Action on incoming requests.

This allows full control of the default Action of the load balancer, including weighted forwarding. See the NetworkListenerAction class for all options.

Parameters:
Return type:

None

add_certificates(id, certificates)

Add one or more certificates to this listener.

After the first certificate, this creates NetworkListenerCertificates resources since cloudformation requires the certificates array on the listener resource to have a length of 1.

Parameters:
Return type:

None

add_target_groups(_id, *target_groups)

Load balance incoming requests to the given target groups.

All target groups will be load balanced to with equal weight and without stickiness. For a more complex configuration than that, use addAction().

Parameters:
Return type:

None

add_targets(id, *, port, deregistration_delay=None, health_check=None, preserve_client_ip=None, protocol=None, proxy_protocol_v2=None, target_group_name=None, targets=None)

Load balance incoming requests to the given load balancing targets.

This method implicitly creates a NetworkTargetGroup for the targets involved, and a ‘forward’ action to route traffic to the given TargetGroup.

If you want more control over the precise setup, create the TargetGroup and use addAction yourself.

It’s possible to add conditions to the targets added in this way. At least one set of targets must be added without conditions.

Parameters:
  • id (str) –

  • port (Union[int, float]) – The port on which the target receives traffic. Default: Determined from protocol if known

  • deregistration_delay (Optional[Duration]) – The amount of time for Elastic Load Balancing to wait before deregistering a target. The range is 0-3600 seconds. Default: Duration.minutes(5)

  • health_check (Union[HealthCheck, Dict[str, Any], None]) – Health check configuration. Default: - The default value for each property in this configuration varies depending on the target.

  • preserve_client_ip (Optional[bool]) – Indicates whether client IP preservation is enabled. Default: false if the target group type is IP address and the target group protocol is TCP or TLS. Otherwise, true.

  • protocol (Optional[Protocol]) – Protocol for target group, expects TCP, TLS, UDP, or TCP_UDP. Default: - inherits the protocol of the listener

  • proxy_protocol_v2 (Optional[bool]) – Indicates whether Proxy Protocol version 2 is enabled. Default: false

  • target_group_name (Optional[str]) – The name of the target group. This name must be unique per region per account, can have a maximum of 32 characters, must contain only alphanumeric characters or hyphens, and must not begin or end with a hyphen. Default: Automatically generated

  • targets (Optional[Sequence[INetworkLoadBalancerTarget]]) – The targets to add to this target group. Can be Instance, IPAddress, or any self-registering load balancing target. If you use either Instance or IPAddress as targets, all target must be of the same type.

Return type:

NetworkTargetGroup

Returns:

The newly created target group

apply_removal_policy(policy)

Apply the given removal policy to this resource.

The Removal Policy controls what happens to this resource when it stops being managed by CloudFormation, either because you’ve removed it from the CDK application or because you’ve made a change that requires the resource to be replaced.

The resource can be deleted (RemovalPolicy.DESTROY), or left in your AWS account for data recovery and cleanup later (RemovalPolicy.RETAIN).

Parameters:

policy (RemovalPolicy) –

Return type:

None

remove_attribute(key)

Remove an attribute from the listener.

Parameters:

key (str) –

Return type:

None

set_attribute(key, value=None)

Set a non-standard attribute on the listener.

Parameters:
  • key (str) –

  • value (Optional[str]) –

See:

https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-elasticloadbalancingv2-listener-listenerattribute.html

Return type:

None

to_string()

Returns a string representation of this construct.

Return type:

str

Attributes

env

The environment this resource belongs to.

For resources that are created and managed by the CDK (generally, those created by creating new class instances like Role, Bucket, etc.), this is always the same as the environment of the stack they belong to; however, for imported resources (those obtained from static methods like fromRoleArn, fromBucketName, etc.), that might be different than the stack they were imported into.

listener_arn

ARN of the listener.

Attribute:

true

load_balancer

The load balancer this listener is attached to.

node

The tree node.

stack

The stack in which this resource is defined.

Static Methods

classmethod from_lookup(scope, id, *, listener_protocol=None, listener_port=None, load_balancer_arn=None, load_balancer_tags=None)

Looks up a network listener.

Parameters:
  • scope (Construct) –

  • id (str) –

  • listener_protocol (Optional[Protocol]) – Protocol of the listener port. Default: - listener is not filtered by protocol

  • listener_port (Union[int, float, None]) – Filter listeners by listener port. Default: - does not filter by listener port

  • load_balancer_arn (Optional[str]) – Filter listeners by associated load balancer arn. Default: - does not filter by load balancer arn

  • load_balancer_tags (Optional[Mapping[str, str]]) – Filter listeners by associated load balancer tags. Default: - does not filter by load balancer tags

Return type:

INetworkListener

classmethod from_network_listener_arn(scope, id, network_listener_arn)

Import an existing listener.

Parameters:
  • scope (Construct) –

  • id (str) –

  • network_listener_arn (str) –

Return type:

INetworkListener

classmethod is_construct(x)

Checks if x is a construct.

Use this method instead of instanceof to properly detect Construct instances, even when the construct library is symlinked.

Explanation: in JavaScript, multiple copies of the constructs library on disk are seen as independent, completely different libraries. As a consequence, the class Construct in each copy of the constructs library is seen as a different class, and an instance of one class will not test as instanceof the other class. npm install will not create installations like this, but users may manually symlink construct libraries together or use a monorepo tool: in those cases, multiple copies of the constructs library can be accidentally installed, and instanceof will behave unpredictably. It is safest to avoid using instanceof, and using this type-testing method instead.

Parameters:

x (Any) – Any object.

Return type:

bool

Returns:

true if x is an object created from a class which extends Construct.

classmethod is_owned_resource(construct)

Returns true if the construct was created by CDK, and false otherwise.

Parameters:

construct (IConstruct) –

Return type:

bool

classmethod is_resource(construct)

Check whether the given construct is a Resource.

Parameters:

construct (IConstruct) –

Return type:

bool