In your JavaScript project, add the web3.storage package to your dependencies:

npm install web3.storage

In your Go project, add the client package to your dependencies using go get:

go get github.com/web3-storage/go-w3s-client

To create a Web3Storage client object, we need to pass an access token into the constructor:

import { Web3Storage } from 'web3.storage'

function getAccessToken () {
  // If you're just testing, you can paste in a token
  // and uncomment the following line:
  // return 'paste-your-token-here'

  // In a real app, it's better to read an access token from an
  // environement variable or other configuration that's kept outside of
  // your code base. For this to work, you need to set the
  // WEB3STORAGE_TOKEN environment variable before you run your code.
  return process.env.WEB3STORAGE_TOKEN
}

function makeStorageClient () {
  return new Web3Storage({ token: getAccessToken() })
}

First, make sure to import the client w3s package:

import "github.com/web3-storage/go-w3s-client"

You can create a client instance with the [NewClient function][reference-go-newclient], passing in an API token using the [WithToken option][reference-go-withtoken]:

token := "<AUTH_TOKEN_GOES_HERE>"
client, err := w3s.NewClient(w3s.WithToken(token))

The client object's status method accepts a CID string and returns a JSON object with information about the upload. Here's how to include it in your project:

async function checkStatus (cid) {
  const client = makeStorageClient()
  const status = await client.status(cid)
  console.log(status)
  if (status) {
    // your code to do something fun with the status info here
  }
}

// replace with your own CID to see info about your uploads!
checkStatus('bafybeifljln6rmvrdqu7xopiwk2bykwa25onxnvjsmlp3xdiii3opgg2gq')

If the given CID is valid and has been uploaded to web3.storage, the status method will return an object that looks similar to this:

{
  "cid": "bafybeiepdjmu7bkau2sv5hag4m76jyt747d4do6kenhedpvd24kcc2zq7u",
  "created": "2021-08-24T21:35:31.988241Z",
  "dagSize": 15393,
  "pins": [
    {
      "status": "Pinned",
      "updated": "2021-08-24T21:39:40.586057Z",
      "peerId": "12D3KooWMbibcXHwkSjgV7VZ8TMfDKi6pZvmi97P83ZwHm9LEsvV",
      "peerName": "web3-storage-dc13",
      "region": "US-DC"
    },
    {
      "status": "Pinned",
      "updated": "2021-08-24T21:39:40.586057Z",
      "peerId": "12D3KooWF6uxxqZf4sXpQEbNE4BfbVJWAKWrFSKamxmWm4E9vyzd",
      "peerName": "web3-storage-am6",
      "region": "NL"
    },
    {
      "status": "Pinned",
      "updated": "2021-08-24T21:39:40.586057Z",
      "peerId": "12D3KooWLWFUri36dmTkki6o9PwfQNwGb2gsHuKD5FdcwzCXYnwc",
      "peerName": "web3-storage-am6-2",
      "region": "NL"
    }
  ],
  "deals": [
    {
      "dealId": 2332952,
      "storageProvider": "f022142",
      "status": "Active",
      "pieceCid": "baga6ea4seaqo6jfxitxwcgcemdcqnmnqan7p7u4l76k3orjqjdo5lengpiorcia",
      "dataCid": "bafybeie2bpl25wxuif2r6zlsq4l77h2jbldscr2yn3jz7iy4pqdd725fau",
      "dataModelSelector": "Links/47/Hash/Links/15/Hash/Links/0/Hash",
      "activation": "2021-08-25T13:00:30Z",
      "created": "2021-08-25T00:17:10.392875Z",
      "updated": "2021-08-25T07:57:26.999531Z"
    },
    {
      "dealId": 2333120,
      "storageProvider": "f022352",
      "status": "Active",
      "pieceCid": "baga6ea4seaqo6jfxitxwcgcemdcqnmnqan7p7u4l76k3orjqjdo5lengpiorcia",
      "dataCid": "bafybeie2bpl25wxuif2r6zlsq4l77h2jbldscr2yn3jz7iy4pqdd725fau",
      "dataModelSelector": "Links/47/Hash/Links/15/Hash/Links/0/Hash",
      "activation": "2021-08-25T14:50:30Z",
      "created": "2021-08-25T01:00:28.410557Z",
      "updated": "2021-08-25T07:57:26.307022Z"
    },
    {
      "dealId": 2333678,
      "storageProvider": "f01278",
      "status": "Published",
      "pieceCid": "baga6ea4seaqo6jfxitxwcgcemdcqnmnqan7p7u4l76k3orjqjdo5lengpiorcia",
      "dataCid": "bafybeie2bpl25wxuif2r6zlsq4l77h2jbldscr2yn3jz7iy4pqdd725fau",
      "dataModelSelector": "Links/47/Hash/Links/15/Hash/Links/0/Hash",
      "activation": "2021-08-26T23:37:30Z",
      "created": "2021-08-25T03:02:14.998793Z",
      "updated": "2021-08-25T07:57:26.639659Z"
    }
  ]
}

What do all those fields mean? Here's a summary:

• cid contains the same CID that was passed into the status method, so you don't have to keep track of which response goes with which request.
• created contains an ISO-8601 datetime string indicating when the content was first uploaded to web3.storage.
• dagSize contains the size in bytes of the Directed Acyclic Graph (DAG) that contains all the uploaded content. This is the size of the data that is transferred over the network to web3.storage during upload, and is slightly larger than the total size of the files on disk.
• pins contains an array of objects describing the IPFS nodes that have pinned the data, making it available for fast retrieval using the IPFS network.
• deals contains an array of objects describing the Filecoin storage providers that have made storage deals. These storage providers have committed to storing the data for an agreed period of time. Note that it may take up to 48 hours after uploading data to web3.storage before Filecoin deals are activated.

For more details about the fields in this JSON response, including the format of the pins and deals objects, see the JavaScript client library reference.

The Go client's Client interface defines a Status method that accepts a context.Context and a Cid from the go-cid library.

The example below accepts a CID string and converts it to a Cid using cid.Parse. If your codebase is already using the Cid type, you may not need this step.

func getStatusForCidString(client w3s.Client, cidString string) error {
	c, err := cid.Parse(cidString)
	if err != nil {
		return err
	}

	s, err := client.Status(context.Background(), c)
	if err != nil {
		return err
	}

	fmt.Printf("Status: %+v", s)
	return nil
}