Installation

Create a new yarn project:

yarn init

Add the Lit Ceramic SDK package:

yarn add lit-ceramic-sdk

Import the SDK

Within your main Typescript file (in the example, app.ts)

import { Integration } from 'lit-ceramic-sdk'

Create a new Integration that runs upon startup and is accessible where you intend to do encryptAndWrite or readAndDecrypt operations. Pass your Ceramic RPC URL and the chain you wish to use:

let litCeramicIntegration = new Integration("https://ceramic-clay.3boxlabs.com", "ethereum")

Instantiating the Lit Client

Start the Lit Client when the DOM is loaded, or early on in the lifecycle:

litCeramicIntegration.startLitClient(window)

Encrypting

First the string will need to be encrypted using the Lit Ceramic SDK.

Set access control conditions, in this example the access is for any wallet that holds a minimum of 0.000001 ETH.

  const accessControlConditions = [
    {
      contractAddress: '',
      standardContractType: '',
      chain: 'ethereum',
      method: 'eth_getBalance',
      parameters: [':userAddress', 'latest'],
      returnValueTest: {
        comparator: '>=',
        value: '1000000000000',  // 0.000001 ETH
      },
    },
  ]

const stringToEncrypt = 'This is what we want to encrypt on Lit and then store on ceramic'
const response = litCeramicIntegration
   .encryptAndWrite(stringToEncrypt, accessControlConditions)
   .then((streamID) => console.log(streamID))

This uses an example streamID and prints the secret value to the console.

Save the streamID, you'll need it to decrypt the message.

Decrypting

In order to decrypt the string, pass in the streamID saved from the earlier encrypting step.

    const response = litCeramicIntegration.readAndDecrypt(streamID).then(
      (value) =>
        console.log(value)
    )

In the example code, the decryption element is update and displays the decrypted message.

  (document.getElementById('decryption').innerText = value)