@aws-sdk/client-elastic-load-balancing-v2
Description
AWS SDK for JavaScript ElasticLoadBalancingV2 Client for Node.js, Browser and React Native.
Elastic Load Balancing
A load balancer distributes incoming traffic across targets, such as your EC2 instances. This enables you to increase the availability of your application. The load balancer also monitors the health of its registered targets and ensures that it routes traffic only to healthy targets. You configure your load balancer to accept incoming traffic by specifying one or more listeners, which are configured with a protocol and port number for connections from clients to the load balancer. You configure a target group with a protocol and port number for connections from the load balancer to the targets, and with health check settings to be used when checking the health status of the targets.
Elastic Load Balancing supports the following types of load balancers: Application Load Balancers, Network Load Balancers, Gateway Load Balancers, and Classic Load Balancers. This reference covers the following load balancer types:
-
Application Load Balancer - Operates at the application layer (layer 7) and supports HTTP and HTTPS.
-
Network Load Balancer - Operates at the transport layer (layer 4) and supports TCP, TLS, UDP, and QUIC.
-
Gateway Load Balancer - Operates at the network layer (layer 3).
For more information, see the Elastic Load Balancing User Guide.
All Elastic Load Balancing operations are idempotent, which means that they complete at most one time. If you repeat an operation, it succeeds.
Installing
To install this package, use the CLI of your favorite package manager:
npm install @aws-sdk/client-elastic-load-balancing-v2yarn add @aws-sdk/client-elastic-load-balancing-v2pnpm add @aws-sdk/client-elastic-load-balancing-v2
Getting Started
Import
The AWS SDK is modulized by clients and commands.
To send a request, you only need to import the ElasticLoadBalancingV2Client and
the commands you need, for example DescribeListenersCommand:
// ES5 example
const { ElasticLoadBalancingV2Client, DescribeListenersCommand } = require("@aws-sdk/client-elastic-load-balancing-v2");
// ES6+ example
import { ElasticLoadBalancingV2Client, DescribeListenersCommand } from "@aws-sdk/client-elastic-load-balancing-v2";
Usage
To send a request:
- Instantiate a client with configuration (e.g. credentials, region).
- See docs/CLIENTS for configuration details.
- See @aws-sdk/config for additional options.
- Instantiate a command with input parameters.
- Call the
sendoperation on the client, providing the command object as input.
const client = new ElasticLoadBalancingV2Client({ region: "REGION" });
const params = { /** input parameters */ };
const command = new DescribeListenersCommand(params);
Async/await
We recommend using the await operator to wait for the promise returned by send operation as follows:
// async/await.
try {
const data = await client.send(command);
// process data.
} catch (error) {
// error handling.
} finally {
// finally.
}
Promises
You can also use Promise chaining.
client
.send(command)
.then((data) => {
// process data.
})
.catch((error) => {
// error handling.
})
.finally(() => {
// finally.
});
Aggregated client
The aggregated client class is exported from the same package, but without the "Client" suffix.
ElasticLoadBalancingV2 extends ElasticLoadBalancingV2Client and additionally supports all operations, waiters, and paginators as methods.
This style may be familiar to you from the AWS SDK for JavaScript v2.
If you are bundling the AWS SDK, we recommend using only the bare-bones client (ElasticLoadBalancingV2Client).
More details are in the blog post on
modular packages in AWS SDK for JavaScript.
import { ElasticLoadBalancingV2 } from "@aws-sdk/client-elastic-load-balancing-v2";
const client = new ElasticLoadBalancingV2({ region: "REGION" });
// async/await.
try {
const data = await client.describeListeners(params);
// process data.
} catch (error) {
// error handling.
}
// Promises.
client
.describeListeners(params)
.then((data) => {
// process data.
})
.catch((error) => {
// error handling.
});
// callbacks (not recommended).
client.describeListeners(params, (err, data) => {
// process err and data.
});
Troubleshooting
When the service returns an exception, the error will include the exception information, as well as response metadata (e.g. request id).
try {
const data = await client.send(command);
// process data.
} catch (error) {
const { requestId, cfId, extendedRequestId } = error.$metadata;
console.log({ requestId, cfId, extendedRequestId });
/**
* The keys within exceptions are also parsed.
* You can access them by specifying exception names:
* if (error.name === 'SomeServiceException') {
* const value = error.specialKeyInException;
* }
*/
}
See also docs/ERROR_HANDLING.
Getting Help
Please use these community resources for getting help. We use GitHub issues for tracking bugs and feature requests, but have limited bandwidth to address them.
- Visit the Developer Guide or API Reference.
- Check out the blog posts tagged with
aws-sdk-json AWS Developer Blog. - Ask a question on StackOverflow and tag it with
aws-sdk-js. - Join the AWS JavaScript community on gitter.
- If it turns out that you may have found a bug, please open an issue.
To test your universal JavaScript code in Node.js, browser and react-native environments, visit our code samples repo.
Contributing
This client code is generated automatically. Any modifications will be overwritten the next time the @aws-sdk/client-elastic-load-balancing-v2 package is updated.
To contribute to client you can check our generate clients scripts.
License
This SDK is distributed under the Apache License, Version 2.0, see LICENSE for more information.