You must [generate an Access Key](https://developers.cloudflare.com/r2/api/s3/tokens/) before getting started. All examples will utilize `access_key_id` and `access_key_secret` variables which represent the **Access Key ID** and **Secret Access Key** values you generated.



If you are interested in the newer version of the AWS JavaScript SDK visit this [dedicated aws-sdk-js-v3 example page](https://developers.cloudflare.com/r2/examples/aws/aws-sdk-js-v3/).

JavaScript or TypeScript users may continue to use the [`aws-sdk`](https://www.npmjs.com/package/aws-sdk) npm package as per normal. You must pass in the R2 configuration credentials when instantiating your `S3` service client:

```ts
import S3 from "aws-sdk/clients/s3.js";


const s3 = new S3({
  endpoint: `https://${accountid}.r2.cloudflarestorage.com`,
  accessKeyId: `${access_key_id}`,
  secretAccessKey: `${access_key_secret}`,
  signatureVersion: "v4",
});


console.log(await s3.listBuckets().promise());
//=> {
//=>   Buckets: [
//=>     { Name: 'user-uploads', CreationDate: 2022-04-13T21:23:47.102Z },
//=>     { Name: 'my-bucket-name', CreationDate: 2022-05-07T02:46:49.218Z }
//=>   ],
//=>   Owner: {
//=>     DisplayName: '...',
//=>     ID: '...'
//=>   }
//=> }


console.log(await s3.listObjects({ Bucket: "my-bucket-name" }).promise());
//=> {
//=>   IsTruncated: false,
//=>   Name: 'my-bucket-name',
//=>   CommonPrefixes: [],
//=>   MaxKeys: 1000,
//=>   Contents: [
//=>     {
//=>       Key: 'cat.png',
//=>       LastModified: 2022-05-07T02:50:45.616Z,
//=>       ETag: '"c4da329b38467509049e615c11b0c48a"',
//=>       ChecksumAlgorithm: [],
//=>       Size: 751832,
//=>       Owner: [Object]
//=>     },
//=>     {
//=>       Key: 'todos.txt',
//=>       LastModified: 2022-05-07T21:37:17.150Z,
//=>       ETag: '"29d911f495d1ba7cb3a4d7d15e63236a"',
//=>       ChecksumAlgorithm: [],
//=>       Size: 279,
//=>       Owner: [Object]
//=>     }
//=>   ]
//=> }
```

## Generate presigned URLs

You can also generate presigned links that can be used to share public read or write access to a bucket temporarily.

```ts
// Use the expires property to determine how long the presigned link is valid.
console.log(
  await s3.getSignedUrlPromise("getObject", {
    Bucket: "my-bucket-name",
    Key: "dog.png",
    Expires: 3600,
  }),
);
// https://my-bucket-name.<accountid>.r2.cloudflarestorage.com/dog.png?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=<credential>&X-Amz-Date=<timestamp>&X-Amz-Expires=3600&X-Amz-Signature=<signature>&X-Amz-SignedHeaders=host


// You can also create links for operations such as putObject to allow temporary write access to a specific key.
console.log(
  await s3.getSignedUrlPromise("putObject", {
    Bucket: "my-bucket-name",
    Key: "dog.png",
    Expires: 3600,
  }),
);
```

You can use the link generated by the `putObject` example to upload to the specified bucket and key, until the presigned link expires.

```sh
curl -X PUT https://my-bucket-name.<accountid>.r2.cloudflarestorage.com/dog.png?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=<credential>&X-Amz-Date=<timestamp>&X-Amz-Expires=3600&X-Amz-Signature=<signature>&X-Amz-SignedHeaders=host --data-binary @dog.png
```
