Presigned Urls

This step assumes you have followed the installation steps and initialized the client.

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Why Presigned Urls?

Very rarely should you allow users to download or upload files from/to your bucket directly. This is because it is a security risk and can lead to malicious users accessing your bucket.

Instead, you should use presigned urls. Presigned urls are valid for a limited time and can be used to download or upload files.

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Create a Presigned Url using the StorageSyncClient

The example belows shows how we would create a presigned url for an object called list-of-cats.txt. This assumes the object exists in the root of your bucket.

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(Download) Create a Presigned Url using the SDK to Download a file.

import { StorageSyncClient } from "@storagesync/client";

export async function getPresignedUrl() {
  const client = new StorageSyncClient({
    apiKey: "<YOUR_API_KEY>",
    bucket: "<YOUR_BUCKET_NAME>",
  });

  const url = await client.sign({
    key: "list-of-cats.txt",
    method: "GET",
    expires: 60 * 60, // Expires in 1 hour
  });

  return url;
}

Now the url can be used to allow users to download a file.

Check out our guides/examples to see how you could use this url in your application.

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(Upload) Create a Presigned Url using the SDK to Upload a file.

import { StorageSyncClient } from "@storagesync/client";

export async function putPresignedUrl() {
  const client = new StorageSyncClient({
    apiKey: "<YOUR_API_KEY>",
    bucket: "<YOUR_BUCKET_NAME>",
  });

  const url = await client.sign({
    key: "list-of-cats.txt",
    method: "PUT",
    expires: 60 * 60, // Expires in 1 hour
  });

  return url;
}

Now the url can be used to allow users to upload a file.

Check out our guides/examples to see how you could use this url in your application.