How to query Web3.Storage
In this how-to guide, you'll learn how to query Web3.Storage for information about your files.
When you store a file with Web3.Storage, you receive a content identifier (CID) that you can use to retrieve the file. However, this CID can also be used to query the service for more details about how the data is stored on the decentralized storage networks that Web3.Storage uses under the hood.
This guide will show you how to use Web3.Storage's JavaScript client library or Go client library to get information about content stored on the network. To follow along, you'll need the API token from your Web3.Storage account. If you already have an account and a token, read on. If not, have a look at the quickstart guide to get up and running in just a few minutes for free.
Installing the client
- JavaScript
- Go
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
Creating a client instance
- JavaScript
- Go
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() })
}
Tip
Don't have an access token? Get your Web3.Storage API token in just a few minutes using the instructions in the quickstart guide.
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))
Querying for status information
- JavaScript
- Go
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')
IMPORTANT
Remember to check the return value! If you ask for the status of a CID that Web3.Storage doesn't know about, the status
method will return undefined
instead of a status object. Make sure to check that a return value exists before trying to use it, as we're doing above with the if (status)
conditional statement.
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 thestatus
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.
Tip
If you're looking for info on files you've uploaded, you can also use the Files page on Web3.Storage to see the values for some of the more commonly-used attributes returned by query()
, namely created
, cid
, dagSize
, and the status
and deals
objects of pins
.
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
}
Next steps
If you haven't yet explored in depth how to store data using Web3.Storage, check out the storage how-to guide for a deep dive on how to upload files using the client libraries.
To learn in greater detail how to fetch your data using the Web3.Storage client, or directly from IPFS using a gateway or the IPFS command line, see the how-to guide on retrieval.