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From a Schema to an Attestation

This walkthrough mirrors the tutorial app that lives in tutorial/ in this monorepo.

Goal​

Create:

  1. a schema;
  2. a default portal;
  3. an attestation;
  4. a UI readback of the issued attestation.

1. Install and run the tutorial app​

From the monorepo root:

pnpm install
pnpm --filter @verax-attestation-registry/verax-tutorial dev

2. Instantiate the SDK​

The tutorial app picks the frontend SDK config from the connected chain:

import { VeraxSdk } from "@verax-attestation-registry/verax-sdk";

let sdkConf;
switch (chain.id) {
  case 84532:
    sdkConf = VeraxSdk.DEFAULT_BASE_SEPOLIA_FRONTEND;
    break;
  case 59141:
    sdkConf = VeraxSdk.DEFAULT_LINEA_SEPOLIA_FRONTEND;
    break;
  case 421614:
    sdkConf = VeraxSdk.DEFAULT_ARBITRUM_SEPOLIA_FRONTEND;
    break;
  case 97:
    sdkConf = VeraxSdk.DEFAULT_BSC_TESTNET_FRONTEND;
    break;
  default:
    sdkConf = VeraxSdk.DEFAULT_LINEA_SEPOLIA_FRONTEND;
    break;
}

const veraxSdk = new VeraxSdk(sdkConf, address);

3. Compute or create the schema​

Use the schema string:

const schemaString = "(bool hasCompletedTutorial)";
const schemaId = await veraxSdk.schema.getIdFromSchemaString(schemaString);
const exists = await veraxSdk.schema.isRegistered(schemaId);

If it does not exist:

await veraxSdk.schema.create(
  "Tutorial Schema",
  "This Schema is used for the tutorial",
  "https://ver.ax/#/tutorials",
  schemaString,
  { waitForConfirmation: true },
);

4. Deploy a default portal​

const receipt = await veraxSdk.portal.deployDefaultPortal(
  [],
  "Tutorial Portal",
  "This Portal is used for the tutorial",
  true,
  "Verax Tutorial",
  { waitForConfirmation: true },
);

The emitted PortalRegistered event gives you the new portal address.

5. Issue the attestation​

const receipt = await veraxSdk.portal.attest(
  portalId,
  {
    schemaId,
    expirationDate: Math.floor(Date.now() / 1000) + 30 * 24 * 60 * 60,
    subject: address,
    attestationData: [{ hasCompletedTutorial: true }],
  },
  [],
  { waitForConfirmation: true },
);

The emitted AttestationRegistered event gives you the new attestation ID.

6. Read it back​

const attestation = await veraxSdk.attestation.getAttestation(attestationId);

The tutorial app reads the attestation onchain with getAttestation. For richer explorer-like reads from the subgraph, you can also use findOneById(...), findBy(...), or findByMultiChain(...).

Important correction​

If you build your own version of this tutorial, prefer schema.isRegistered(schemaId) to test existence. The tutorial app calls getSchema(schemaId) instead, which reverts onchain with SchemaNotRegistered on a missing schema.

Next steps​

  • add a module to the portal;
  • replace or revoke the attestation;
  • switch to the canonical Offchain schema if the payload should live on IPFS;
  • query the result through the subgraph.