feat(clients): update README with documentation, usage and more (#1907)

clients/client-accessanalyzer/README.md

@@ -3,4 +3,207 @@
 [![NPM version](https://img.shields.io/npm/v/@aws-sdk/client-accessanalyzer/latest.svg)](https://www.npmjs.com/package/@aws-sdk/client-accessanalyzer)
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-For SDK usage, please step to [SDK readme](https://github.com/aws/aws-sdk-js-v3).
+## Description
+
+AWS SDK for JavaScript AccessAnalyzer Client for Node.js, Browser and React Native.
+
+<p>AWS IAM Access Analyzer helps identify potential resource-access risks by enabling you to identify
+any policies that grant access to an external principal. It does this by using logic-based
+reasoning to analyze resource-based policies in your AWS environment. An external principal
+can be another AWS account, a root user, an IAM user or role, a federated user, an AWS
+service, or an anonymous user. This guide describes the AWS IAM Access Analyzer operations that you can
+call programmatically. For general information about Access Analyzer, see the <a href="https://docs.aws.amazon.com/IAM/latest/UserGuide/what-is-access-analyzer.html">AWS IAM Access Analyzer section of the IAM User Guide</a>.</p>
+<p>To start using Access Analyzer, you first need to create an analyzer.</p>
+
+## Installing
+
+To install the this package, simply type add or install @aws-sdk/client-accessanalyzer
+using your favorite package manager:
+
+- `npm install @aws-sdk/client-accessanalyzer`
+- `yarn add @aws-sdk/client-accessanalyzer`
+- `pnpm add @aws-sdk/client-accessanalyzer`
+
+## Getting Started
+
+### Import
+
+The AWS SDK is modulized by clients and commands.
+To send a request, you only need to import the `AccessAnalyzerClient` and
+the commands you need, for example `CreateAnalyzerCommand`:
+
+```js
+// ES5 example
+const { AccessAnalyzerClient, CreateAnalyzerCommand } = require("@aws-sdk/client-accessanalyzer");
+```
+
+```ts
+// ES6+ example
+import { AccessAnalyzerClient, CreateAnalyzerCommand } from "@aws-sdk/client-accessanalyzer";
+```
+
+### Usage
+
+To send a request, you:
+
+- Initiate client with configuration (e.g. credentials, region).
+- Initiate command with input parameters.
+- Call `send` operation on client with command object as input.
+- If you are using a custom http handler, you may call `destroy()` to close open connections.
+
+```js
+// a client can be shared by difference commands.
+const client = new AccessAnalyzerClient({ region: "REGION" });
+
+const params = {
+  /** input parameters */
+};
+const command = new CreateAnalyzerCommand(params);
+```
+
+#### Async/await
+
+We recommend using [await](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Operators/await)
+operator to wait for the promise returned by send operation as follows:
+
+```js
+// async/await.
+try {
+  const data = await client.send(command);
+  // process data.
+} catch (error) {
+  // error handling.
+} finally {
+  // finally.
+}
+```
+
+Async-await is clean, concise, intuitive, easy to debug and has better error handling
+as compared to using Promise chains or callbacks.
+
+#### Promises
+
+You can also use [Promise chaining](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Using_promises#chaining)
+to execute send operation.
+
+```js
+client.send(command).then(
+  (data) => {
+    // process data.
+  },
+  (error) => {
+    // error handling.
+  }
+);
+```
+
+Promises can also be called using `.catch()` and `.finally()` as follows:
+
+```js
+client
+  .send(command)
+  .then((data) => {
+    // process data.
+  })
+  .catch((error) => {
+    // error handling.
+  })
+  .finally(() => {
+    // finally.
+  });
+```
+
+#### Callbacks
+
+We do not recommend using callbacks because of [callback hell](http://callbackhell.com/),
+but they are supported by the send operation.
+
+```js
+// callbacks.
+client.send(command, (err, data) => {
+  // proccess err and data.
+});
+```
+
+#### v2 compatible style
+
+The client can also send requests using v2 compatible style.
+However, it results in a bigger bundle size and may be dropped in next major version. More details in the blog post
+on [modular packages in AWS SDK for JavaScript](https://aws.amazon.com/blogs/developer/modular-packages-in-aws-sdk-for-javascript/)
+
+```ts
+import * as AWS from "@aws-sdk/client-accessanalyzer";
+const client = new AWS.AccessAnalyzer({ region: "REGION" });
+
+// async/await.
+try {
+  const data = client.createAnalyzer(params);
+  // process data.
+} catch (error) {
+  // error handling.
+}
+
+// Promises.
+client
+  .createAnalyzer(params)
+  .then((data) => {
+    // process data.
+  })
+  .catch((error) => {
+    // error handling.
+  });
+
+// callbacks.
+client.createAnalyzer(params, (err, data) => {
+  // proccess 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).
+
+```js
+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;
+   * }
+   */
+}
+```
+
+## Getting Help
+
+Please use these community resources for getting help.
+We use the GitHub issues for tracking bugs and feature requests, but have limited bandwidth to address them.
+
+- Visit [Developer Guide](https://docs.aws.amazon.com/sdk-for-javascript/v3/developer-guide/welcome.html)
+  or [API Reference](https://docs.aws.amazon.com/AWSJavaScriptSDK/v3/latest/index.html).
+- Check out the blog posts tagged with [`aws-sdk-js`](https://aws.amazon.com/blogs/developer/tag/aws-sdk-js/)
+  on AWS Developer Blog.
+- Ask a question on [StackOverflow](https://stackoverflow.com/questions/tagged/aws-sdk-js) and tag it with `aws-sdk-js`.
+- Join the AWS JavaScript community on [gitter](https://gitter.im/aws/aws-sdk-js-v3).
+- If it turns out that you may have found a bug, please [open an issue](https://github.com/aws/aws-sdk-js-v3/issues/new/choose).
+
+To test your universal JavaScript code in Node.js, browser and react-native environments,
+visit our [code samples repo](https://github.com/aws-samples/aws-sdk-js-tests).
+
+## Contributing
+
+This client code is generated automatically. Any modifications will be overwritten the next time the `@aws-sdk/client-accessanalyzer` package is updated.
+To contribute to client you can check our [generate clients scripts](https://github.com/aws/aws-sdk-js-v3/tree/master/scripts/generate-clients).
+
+## License
+
+This SDK is distributed under the
+[Apache License, Version 2.0](http://www.apache.org/licenses/LICENSE-2.0),
+see LICENSE for more information.