Help Center/ Elastic Load Balance/ API Reference/ APIs (V3)/ Listener/ Viewing Details of a Listener

Updated on 2024-09-26 GMT+08:00

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Viewing Details of a Listener

Function

This API is used to view details of a listener.

Calling Method

For details, see Calling APIs.

URI

GET /v3/{project_id}/elb/listeners/{listener_id}

**Table 1** Path Parameters
Parameter	Mandatory	Type	Description
project_id	Yes	String	Specifies the project ID.
listener_id	Yes	String	Specifies the listener ID.

Request Parameters

**Table 2** Request header parameters
Parameter	Mandatory	Type	Description
X-Auth-Token	Yes	String	Specifies the token used for IAM authentication.

Response Parameters

Status code: 200

**Table 3** Response body parameters
Parameter	Type	Description
request_id	String	Specifies the request ID. Note: The value is automatically generated.
listener	Listener object	Specifies the listener.

**Table 4** Listener
Parameter	Type	Description
admin_state_up	Boolean	Specifies the administrative status of the listener.
client_ca_tls_container_ref	String	Specifies the ID of the CA certificate used by the listener. Notes and constraints: This parameter is available only when type is set to client.
connection_limit	Integer	Specifies the maximum number of connections that the load balancer can establish with backend servers. The default value is -1, indicating that the number of connections is not limited. This parameter is unsupported. Please do not use it.
created_at	String	Specifies the time when the listener was created, in the format of yyyy-MM-dd''T''HH:mm:ss''Z'', for example, 2021-07-30T12:03:44Z.
default_pool_id	String	Specifies the ID of the default backend server group. If there is no matched forwarding policy, requests are forwarded to the default backend server.
default_tls_container_ref	String	Specifies the ID of the server certificate used by the listener.
description	String	Provides supplementary information about the listener.
http2_enable	Boolean	Specifies whether to use HTTP/2 if you want the clients to use HTTP/2 to communicate with the load balancer. Request forwarding using HTTP/2 improves the access performance between your application and the load balancer. However, the load balancer still uses HTTP/1.x to forward requests to the backend server. Notes and constraints: This parameter is available only for HTTPS listeners. For QUIC listeners, it cannot be set and the response is fixed at true. If you configure this parameter for listeners with other protocols, it will not take effect.
id	String	Specifies the listener ID.
insert_headers	ListenerInsertHeaders object	Specifies the HTTP header fields that can transmit required information to backend servers. For example, the X-Forwarded-ELB-IP header field can transmit the EIP of the load balancer to backend servers.
loadbalancers	Array of LoadBalancerRef objects	Specifies the ID of the load balancer that the listener is added to. Notes and constraints: A listener can be added to only one load balancer.
name	String	Specifies the listener name. Notes and constraints: If you leave the listener name empty, you cannot locate it on the listener list and view its details.
project_id	String	Specifies the project ID used by the listener.
protocol	String	Specifies the protocol used by the listener. The value can be TCP, UDP, HTTP, HTTPS, TERMINATED_HTTPS, QUIC, or TLS. Notes and constraints: Protocol used by HTTPS listeners added to a shared load balancer can only be set to TERMINATED_HTTPS. If HTTPS is passed, the value will be automatically changed to TERMINATED_HTTPS. Protocol used by HTTPS listeners added to a dedicated load balancer can only be set to HTTPS. If TERMINATED_HTTPS is passed, the value will be automatically changed to HTTPS.
protocol_port	Integer	Specifies the port used by the listener. Notes and constraints: The QUIC listener port cannot be 4789 or the same as the UDP listener port. If this parameter is set to 0, port_ranges is required.
sni_container_refs	Array of strings	Specifies the IDs of SNI certificates (server certificates with domain names) used by the listener. Notes and constraints: The domain names of all SNI certificates must be unique. The total number of domain names of all SNI certificates cannot exceed 50.
sni_match_algo	String	Specifies how wildcard domain name matches with the SNI certificates used by the listener. The value can be: longest_suffix: indicates longest suffix match. wildcard (default): indicates wildcard match.
tags	Array of Tag objects	Lists the tags.
updated_at	String	Specifies the time when the listener was updated, in the format of yyyy-MM-dd''T''HH:mm:ss''Z'', for example, 2021-07-30T12:03:44Z.
tls_ciphers_policy	String	Specifies the security policy used by the listener. The value can be tls-1-0-inherit, tls-1-0, tls-1-1, tls-1-2, tls-1-2-strict, tls-1-2-fs, tls-1-0-with-1-3, tls-1-2-fs-with-1-3, hybrid-policy-1-0, tls-1-2-strict-no-cbc, or tls-1-0 (default). Notes and constraints: This parameter will take effect only for HTTPS listeners added to a dedicated load balancer. This parameter is not available for QUIC listeners. If both security_policy_id and tls_ciphers_policy are specified, only security_policy_id will take effect. The priority of the encryption suite from high to low is: ecc suite, rsa suite, tls 1.3 suite (supporting both ecc and rsa).
security_policy_id	String	Specifies the ID of the custom security policy. Notes and constraints: This parameter will take effect only for HTTPS listeners added to a dedicated load balancer. This parameter is not available for QUIC listeners. If both security_policy_id and tls_ciphers_policy are specified, only security_policy_id will take effect. The priority of the encryption suite from high to low is: ecc suite, rsa suite, tls 1.3 suite (supporting both ecc and rsa).
enable_member_retry	Boolean	Specifies whether to enable health check retries for backend servers. The value can be: true (default): Health check retries will be enabled. false: Health check retries will be disabled. Notes and constraints: If a shared load balancer is associated, this parameter is available only when protocol is set to HTTP or TERMINATED_HTTPS. If a dedicated load balancer is associated, this parameter is available only when protocol is set to HTTP, HTTPS, or QUIC.
keepalive_timeout	Integer	Specifies the idle timeout duration, in seconds. If there are no requests reaching the load balancer after the idle timeout duration elapses, the load balancer will disconnect the connection with the client and establish a new connection when there is a new request. Value ranges: For TCP listeners, the value ranges from 10 to 4000, and the default value is 300. For HTTP, HTTPS, and TERMINATED_HTTPS listeners, the value ranges from 0 to 4000, and the default value is 60. Notes and constraints: For UDP listeners of shared load balancers, this parameter does not take effect.
client_timeout	Integer	Specifies the timeout duration for waiting for a response from a client, in seconds. There are two situations: If the client fails to send a request header to the load balancer within the timeout duration, the request will be interrupted. If the interval between two consecutive request bodies reaching the load balancer is greater than the timeout duration, the connection will be disconnected. The value ranges from 1 to 3600, and the default value is 60. This parameter is available only for HTTP and HTTPS listeners.
member_timeout	Integer	Specifies the timeout duration for waiting for a response from a backend server, in seconds. If the backend server fails to respond after the timeout duration elapses, the load balancer will stop waiting and return HTTP 504 Gateway Timeout to the client. The value ranges from 1 to 3600, and the default value is 60. This parameter is available only for HTTP and HTTPS listeners.
ipgroup	ListenerIpGroup object	Specifies the IP address group associated with the listener.
transparent_client_ip_enable	Boolean	Specifies whether to pass source IP addresses of the clients to backend servers. Value ranges: TCP or UDP listeners of shared load balancers: The value can be true or false, and the default value is false if this parameter is not passed. HTTP or HTTPS listeners of shared load balancers: The value can only be true, and the default value is true if this parameter is not passed. All listeners of dedicated load balancers: The value can only be true, and the default value is true if this parameter is not passed. Notes and constraints: This function can only be enabled or disabled for TCP or UDP listeners of shared load balancers. If this function is enabled, the load balancer communicates with backend servers using their real IP addresses. Ensure that security group rules and access control policies are correctly configured. If this function is enabled, a server cannot serve as both a backend server and a client. If this function is enabled, backend server specifications cannot be changed.
proxy_protocol_enable	Boolean	Specifies whether to enable the ProxyProtocol option. Notes and constraints: This parameter is available only for TLS listeners and does not take effect for other types of listeners.
enhance_l7policy_enable	Boolean	Specifies whether to enable advanced forwarding. If advanced forwarding is enabled, more flexible forwarding policies and rules are supported. The value can be: true: Enable advanced forwarding. false (default): Disable advanced forwarding. Notes and constraints: Advanced forwarding cannot be disabled once it is enabled. action can be set to REDIRECT_TO_URL (requests will be redirected to another URL) or Fixed_RESPONSE (a fixed response body will be returned to clients). Parameters priority, redirect_url_config, and fixed_response_config can be specified in a forwarding policy. type can be set to METHOD, HEADER, QUERY_STRING, or SOURCE_IP for a forwarding rule. If type is set to HOST_NAME for a forwarding rule, the value of the forwarding rule supports wildcard asterisks (). Parameter conditions* can be specified for forwarding rules.
quic_config	ListenerQuicConfig object	Specifies the QUIC configuration for the current listener. Notes and constraints: This parameter is valid only when protocol is set to HTTPS. For a TCP, UDP, HTTP, or QUIC listener, if this parameter is not left blank, an error will be reported. The client sends a normal HTTP request that contains information indicating that the QUIC protocol is supported. If QUIC upgrade is enabled for the listeners, QUIC port and version information will be added to the response header. When the client sends both HTTPS and QUIC requests to the server, if the QUIC request is successfully sent, QUIC protocol will be used for subsequent communications.
protection_status	String	Specifies the protection status. The value can be: nonProtection (default): The resource is not protected against being modified by accident. consoleProtection: The resource is protected against being modified by accident.
protection_reason	String	Specifies why the modification protection function is enabled. Notes and constraints: This parameter is valid only when protection_status is set to consoleProtection.
gzip_enable	Boolean	Specifies whether to enable gzip compression for a load balancer. The value can be true or false, and the default value is false. Notes and constraints: This parameter can be configured only for HTTP, HTTPS, and QUIC listeners.

**Table 5** ListenerInsertHeaders
Parameter	Type	Description
X-Forwarded-ELB-IP	Boolean	Specifies whether to transparently transmit the load balancer EIP to backend servers. If X-Forwarded-ELB-IP is set to true, the load balancer EIP will be stored in the HTTP header and passed to backend servers.
X-Forwarded-Port	Boolean	Specifies whether to transparently transmit the listening port of the load balancer to backend servers. If X-Forwarded-Port is set to true, the listening port of the load balancer will be stored in the HTTP header and passed to backend servers.
X-Forwarded-For-Port	Boolean	Specifies whether to transparently transmit the source port of the client to backend servers. If X-Forwarded-For-Port is set to true, the source port of the client will be stored in the HTTP header and passed to backend servers.
X-Forwarded-Host	Boolean	Specifies whether to rewrite the X-Forwarded-Host header. If X-Forwarded-Host is set to true, X-Forwarded-Host in the request header from the clients can be set to Host in the request header sent from the load balancer to backend servers.
X-Forwarded-Proto	Boolean	If X-Forwarded-Proto is set to true, the listener protocol of the load balancer can be transferred to backend servers through the HTTP header of the packet.
X-Real-IP	Boolean	If X-Real-IP is set to true, the source IP address of the client can be transferred to backend servers through the HTTP header of the packet.
X-Forwarded-ELB-ID	Boolean	If X-Forwarded-ELB-ID is set to true, the load balancer ID can be transferred to backend servers through the HTTP header of the packet.
X-Forwarded-TLS-Certificate-ID	Boolean	If X-Forwarded-TLS-Certificate-ID is set to true, the certificate ID of the load balancer can be transferred to backend servers through the HTTP header of the packet.
X-Forwarded-TLS-Protocol	Boolean	If X-Forwarded-TLS-Protocol is set to true, the algorithm protocol of the load balancer can be transferred to backend servers through the HTTP header of the packet.
X-Forwarded-TLS-Cipher	Boolean	If X-Forwarded-TLS-Cipher is set to true, the algorithm suite of the load balancer can be transferred to backend servers through the HTTP header of the packet.

**Table 6** LoadBalancerRef
Parameter	Type	Description
id	String	Specifies the load balancer ID.

**Table 7** Tag
Parameter	Type	Description
key	String	Specifies the tag key.
value	String	Specifies the tag value.

**Table 8** ListenerIpGroup
Parameter	Type	Description
ipgroup_id	String	Specifies the ID of the IP address group associated with the listener. Notes and constraints: This parameter is mandatory when you create the IP address group and is optional when you update the IP address group. The specified IP address group must exist, and the value cannot be null.
enable_ipgroup	Boolean	Specifies whether to enable access control. The value can be: true: Access control will be enabled. false: Access control will be disabled.
type	String	Specifies how access to the listener is controlled. The value can be: white: A whitelist will be configured. Only IP addresses in the whitelist can access the listener. black: A blacklist will be configured. IP addresses in the blacklist are not allowed to access the listener.

**Table 9** ListenerQuicConfig
Parameter	Type	Description
quic_listener_id	String	Specifies the ID of the QUIC listener. This parameter is mandatory for creation and is optional for update. The listener specified by quic_listener_id must exist. The listener protocol must be QUIC and cannot be set to null, otherwise, it will conflict with enable_quic_upgrade.
enable_quic_upgrade	Boolean	Specifies whether to enable QUIC upgrade. The value can be: true: QUIC upgrade is enabled. false: QUIC upgrade is disabled. HTTPS listeners can be upgraded to QUIC listeners.

Example Requests

Viewing details of a listener

GET https://{ELB_Endpoint}/v3/99a3fff0d03c428eac3678da6a7d0f24/elb/listeners/0b11747a-b139-492f-9692-2df0b1c87193

Example Responses

Status code: 200

Successful request.

{
  "listener" : {
    "id" : "0b11747a-b139-492f-9692-2df0b1c87193",
    "name" : "My listener",
    "protocol_port" : 80,
    "protocol" : "TCP",
    "ipgroup" : null,
    "description" : "My listener update.",
    "default_tls_container_ref" : null,
    "admin_state_up" : true,
    "loadbalancers" : [ {
      "id" : "098b2f68-af1c-41a9-8efd-69958722af62"
    } ],
    "member_timeout" : null,
    "client_timeout" : null,
    "keepalive_timeout" : 300,
    "client_ca_tls_container_ref" : null,
    "project_id" : "99a3fff0d03c428eac3678da6a7d0f24",
    "sni_container_refs" : [ ],
    "connection_limit" : -1,
    "default_pool_id" : null,
    "tls_ciphers_policy" : "tls-1-0",
    "tags" : [ ],
    "created_at" : "2019-04-02T00:12:32Z",
    "updated_at" : "2019-04-02T17:43:46Z",
    "http2_enable" : true,
    "insert_headers" : {
      "X-Forwarded-ELB-IP" : true
    },
    "transparent_client_ip_enable" : false
  },
  "request_id" : "1394eb39-e4c8-4177-b96d-aaff569f1833"
}

SDK Sample Code

The SDK sample code is as follows.

      
       
         
         
           package com.huaweicloud.sdk.test;

import com.huaweicloud.sdk.core.auth.ICredential;
import com.huaweicloud.sdk.core.auth.BasicCredentials;
import com.huaweicloud.sdk.core.exception.ConnectionException;
import com.huaweicloud.sdk.core.exception.RequestTimeoutException;
import com.huaweicloud.sdk.core.exception.ServiceResponseException;
import com.huaweicloud.sdk.elb.v3.region.ElbRegion;
import com.huaweicloud.sdk.elb.v3.*;
import com.huaweicloud.sdk.elb.v3.model.*;


public class ShowListenerSolution {

    public static void main(String[] args) {
        // The AK and SK used for authentication are hard-coded or stored in plaintext, which has great security risks. It is recommended that the AK and SK be stored in ciphertext in configuration files or environment variables and decrypted during use to ensure security.
        // In this example, AK and SK are stored in environment variables for authentication. Before running this example, set environment variables CLOUD_SDK_AK and CLOUD_SDK_SK in the local environment
        String ak = System.getenv("CLOUD_SDK_AK");
        String sk = System.getenv("CLOUD_SDK_SK");
        String projectId = "{project_id}";

        ICredential auth = new BasicCredentials()
                .withProjectId(projectId)
                .withAk(ak)
                .withSk(sk);

        ElbClient client = ElbClient.newBuilder()
                .withCredential(auth)
                .withRegion(ElbRegion.valueOf("<YOUR REGION>"))
                .build();
        ShowListenerRequest request = new ShowListenerRequest();
        request.withListenerId("{listener_id}");
        try {
            ShowListenerResponse response = client.showListener(request);
            System.out.println(response.toString());
        } catch (ConnectionException e) {
            e.printStackTrace();
        } catch (RequestTimeoutException e) {
            e.printStackTrace();
        } catch (ServiceResponseException e) {
            e.printStackTrace();
            System.out.println(e.getHttpStatusCode());
            System.out.println(e.getRequestId());
            System.out.println(e.getErrorCode());
            System.out.println(e.getErrorMsg());
        }
    }
}

          

        

      
     

      
       
         
         
           # coding: utf-8

import os
from huaweicloudsdkcore.auth.credentials import BasicCredentials
from huaweicloudsdkelb.v3.region.elb_region import ElbRegion
from huaweicloudsdkcore.exceptions import exceptions
from huaweicloudsdkelb.v3 import *

if __name__ == "__main__":
    # The AK and SK used for authentication are hard-coded or stored in plaintext, which has great security risks. It is recommended that the AK and SK be stored in ciphertext in configuration files or environment variables and decrypted during use to ensure security.
    # In this example, AK and SK are stored in environment variables for authentication. Before running this example, set environment variables CLOUD_SDK_AK and CLOUD_SDK_SK in the local environment
    ak = os.environ["CLOUD_SDK_AK"]
    sk = os.environ["CLOUD_SDK_SK"]
    projectId = "{project_id}"

    credentials = BasicCredentials(ak, sk, projectId)

    client = ElbClient.new_builder() \
        .with_credentials(credentials) \
        .with_region(ElbRegion.value_of("<YOUR REGION>")) \
        .build()

    try:
        request = ShowListenerRequest()
        request.listener_id = "{listener_id}"
        response = client.show_listener(request)
        print(response)
    except exceptions.ClientRequestException as e:
        print(e.status_code)
        print(e.request_id)
        print(e.error_code)
        print(e.error_msg)

          

        

      
     

      
       
         
         
           package main

import (
	"fmt"
	"github.com/huaweicloud/huaweicloud-sdk-go-v3/core/auth/basic"
    elb "github.com/huaweicloud/huaweicloud-sdk-go-v3/services/elb/v3"
	"github.com/huaweicloud/huaweicloud-sdk-go-v3/services/elb/v3/model"
    region "github.com/huaweicloud/huaweicloud-sdk-go-v3/services/elb/v3/region"
)

func main() {
    // The AK and SK used for authentication are hard-coded or stored in plaintext, which has great security risks. It is recommended that the AK and SK be stored in ciphertext in configuration files or environment variables and decrypted during use to ensure security.
    // In this example, AK and SK are stored in environment variables for authentication. Before running this example, set environment variables CLOUD_SDK_AK and CLOUD_SDK_SK in the local environment
    ak := os.Getenv("CLOUD_SDK_AK")
    sk := os.Getenv("CLOUD_SDK_SK")
    projectId := "{project_id}"

    auth := basic.NewCredentialsBuilder().
        WithAk(ak).
        WithSk(sk).
        WithProjectId(projectId).
        Build()

    client := elb.NewElbClient(
        elb.ElbClientBuilder().
            WithRegion(region.ValueOf("<YOUR REGION>")).
            WithCredential(auth).
            Build())

    request := &model.ShowListenerRequest{}
	request.ListenerId = "{listener_id}"
	response, err := client.ShowListener(request)
	if err == nil {
        fmt.Printf("%+v\n", response)
    } else {
        fmt.Println(err)
    }
}

          

        

      
     