The Content Addressable plugin works in tandem with the Signatures API, allowing users to get a signature field in the headers of a Dedicated Gateway request. This can be very useful to help verify content ownership when retrieving files from IPFS.
For more information about adding signatures to CIDs on IPFS please read the Signatures Guide

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Installation

Follow the steps in the Getting Started guide to install the Content Addressable Plugin.

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Usage

Once the plugin is installed the rest is quite simple. If a CID as a signature attached to it, then there will be a pinata-signature field in the headers. 
const signatureReq = await fetch(
  `https://<YOUR_GATEWAY_DOMAIN>.mypinata.cloud/ipfs/<CID>`,
  {
    method: "HEAD",
  }
);
const signature = signatureReq.headers.get("pinata-signature");

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