The [AWS SDK for JavaScript V3 API Reference Guide](https://docs.aws.amazon.com/AWSJavaScriptSDK/v3/latest/) describes in detail all the API operations for the AWS SDK for JavaScript version 3 (V3).
# Amazon Polly examples
![\[JavaScript code example that applies to Node.js execution\]](http://docs.aws.amazon.com/sdk-for-javascript/v3/developer-guide/images/nodeicon.png)
**This Node.js code example shows:**
+ Upload audio recorded using Amazon Polly to Amazon S3
## The scenario
In this example, a series of Node.js modules are used to automatically upload audio recorded using Amazon Polly to Amazon S3 using these methods of the Amazon S3 client class:
+ [https://docs.aws.amazon.com/AWSJavaScriptSDK/v3/latest/Package/-aws-sdk-client-polly/Class/StartSpeechSynthesisTaskCommand/](https://docs.aws.amazon.com/AWSJavaScriptSDK/v3/latest/Package/-aws-sdk-client-polly/Class/StartSpeechSynthesisTaskCommand/)
## Prerequisite tasks
To set up and run this example, you must first complete these tasks:
+ Set up a project environment to run Node JavaScript examples by following the instructions on[ GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/tree/master/javascriptv3/example_code/s3/README.md).
+ Create a shared configurations file with your user credentials. For more information about providing a shared credentials file, see [Shared config and credentials files](https://docs.aws.amazon.com/sdkref/latest/guide/file-format.html) in the *AWS SDKs and Tools Reference Guide*.
+ Create an AWS Identity and Access Management (IAM) Unauthenticated Amazon Cognito user role polly:SynthesizeSpeech permissions, and an Amazon Cognito identity pool with the IAM role attached to it. The [Create the AWS resources using the CloudFormation](#polly-example-synthesize-to-s3-create-resources)section below describes how to create these resources.
**Note**
This example uses Amazon Cognito, but if you are not using Amazon Cognito then your AWS user must have following IAM permissions policy
****
```
{
"Version":"2012-10-17",
"Statement": [
{
"Action": [
"mobileanalytics:PutEvents",
"cognito-sync:*"
],
"Resource": "*",
"Effect": "Allow"
},
{
"Action": "polly:SynthesizeSpeech",
"Resource": "*",
"Effect": "Allow"
}
]
}
```
## Create the AWS resources using the CloudFormation
CloudFormation enables you to create and provision AWS infrastructure deployments predictably and repeatedly. For more information about CloudFormation, see the [AWS CloudFormation User Guide](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/).
To create the CloudFormation stack:
1. Install and configure the AWS CLI following the instructions in the [AWS CLI User Guide](https://docs.aws.amazon.com/cli/latest/userguide/cli-chap-welcome.html).
1. Create a file named `setup.yaml` in the root directory of your project folder, and copy the content [ here on GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/blob/main/javascriptv3/example_code/polly/general-examples/src/setup.yaml) into it.
**Note**
The CloudFormation template was generated using the AWS CDK available [here on GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/blob/main/resources/cdk/javascript_example_code_polly_aws_service/). For more information about the AWS CDK, see the [AWS Cloud Development Kit (AWS CDK) Developer Guide](https://docs.aws.amazon.com/cdk/latest/guide/).
1. Run the following command from the command line, replacing *STACK\$1NAME* with a unique name for the stack.
**Important**
The stack name must be unique within an AWS Region and AWS account. You can specify up to 128 characters, and numbers and hyphens are allowed.
```
aws cloudformation create-stack --stack-name STACK_NAME --template-body file://setup.yaml --capabilities CAPABILITY_IAM
```
For more information on the `create-stack` command parameters, see the [AWS CLI Command Reference guide](https://docs.aws.amazon.com/cli/latest/reference/cloudformation/create-stack.html), and the [CloudFormation User Guide](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-cli-creating-stack.html).
1. Navigate to the CloudFormation management console, choose **Stacks**, choose the stack name, and choose the **Resources** tab to view a list of the created resources.
![\[CloudFormation resources\]](http://docs.aws.amazon.com/sdk-for-javascript/v3/developer-guide/images/cfn_polly.png)
## Upload audio recorded using Amazon Polly to Amazon S3
Create a Node.js module with the file name `polly_synthesize_to_s3.js`. Make sure to configure the SDK as previously shown, including installing the required clients and packages. In the code, enter the *REGION*, and the *BUCKET\$1NAME*. To access Amazon Polly, create an `Polly` client service object. Replace *"IDENTITY\$1POOL\$1ID"* with the `IdentityPoolId` from the **Sample page** of the Amazon Cognito identity pool you created for this example. This is also passed to each client object.
Call the `StartSpeechSynthesisCommand` method of the Amazon Polly client service object synthesize the voice message and upload it to the Amazon S3 bucket.
```
import { StartSpeechSynthesisTaskCommand } from "@aws-sdk/client-polly";
import { pollyClient } from "./libs/pollyClient.js";
// Create the parameters
const params = {
OutputFormat: "mp3",
OutputS3BucketName: "videoanalyzerbucket",
Text: "Hello David, How are you?",
TextType: "text",
VoiceId: "Joanna",
SampleRate: "22050",
};
const run = async () => {
try {
await pollyClient.send(new StartSpeechSynthesisTaskCommand(params));
console.log(`Success, audio file added to ${params.OutputS3BucketName}`);
} catch (err) {
console.log("Error putting object", err);
}
};
run();
```
This sample code can be found [here on GitHub](https://github.com/awsdocs/aws-doc-sdk-examples/blob/master/javascriptv3/example_code/polly/general-examples/src/polly_synthesize_to_s3.js).