AssetBuilder

Builds the metadata for an asset you want to publish or edit, with a typesafe fluent API.

Instantiating

Two modes, chosen by whether you pass an existing asset.

import { AssetBuilder } from '@deltadao/nautilus'
 
const builder = new AssetBuilder() 
an empty asset, to be filled in

import { AssetBuilder, Nautilus } from '@deltadao/nautilus'
import { Wallet } from 'ethers'
 
const nautilus = await Nautilus.create(new Wallet('0x1234'))
 
const published = await nautilus.getAsset( 
  'did:ope:2a6ebce0af9361e2c7d1e1e7909ecac3e4cabb4f089f7edd51865e0b77a5c216'
) 
 
const editBuilder = new AssetBuilder(published) 

In edit mode the builder seeds itself from the published document, including its owner and lifecycle state, and immediately strips the indexer-derived fields so they can never be signed back in. Setting one field leaves everything else intact: the merge is structural, not top-level, so you never have to resupply metadata you are not changing.

reset() returns to whichever state the constructor produced. In edit mode that means the loaded asset — v1 emptied the builder, which made reset() unusable while editing.

A minimal new asset

const minimal = new AssetBuilder()
  .setType('dataset') // required
  .setName('Hourly Weather Observations') // required
  .setProvidedBy('deltaDAO AG') // required by DDO v5
  .addService(minimalService) // at least one
  .build()

build() rejects a new asset missing name, type or providedBy, and one with no services. An algorithm also needs container metadata. Everything else is checked by publish, which validates the whole DDO locally against the DDO v5 schema before spending gas.

DDO v5 changes worth knowing

Three setters take the same arguments as in v1 but produce a different shape, because DDO v5 changed the fields. The builder absorbs that, so you keep passing plain strings.

// Stored as { '@value', '@language', '@direction' } — v4 used a plain string.
shapes.setDescription('One row per hour, comma separated')
 
// Stored as { name } — v4 used a plain string. Pass the object form for ODRL terms.
shapes.setLicense('https://market.oceanprotocol.com/terms')
 
// Stored as a { label: url } map — v4 used an array. An array still works, keyed by index.
shapes.addLinks(['https://docs.example'])
shapes.addLinks({ docs: 'https://docs.example' })

setContentLanguage was repurposed. In v4 it wrote a contentLanguage metadata field; v5 moved the language onto each value, so it now sets the tag applied to every language-tagged field the builder emits:

language.setContentLanguage('de', 'ltr') 
language.setDescription('Stündliche Wetterbeobachtungen')
description: { '@value': '...', '@language': 'de', '@direction': 'ltr' }

It defaults to en / ltr.

Gating access

Address lists work as they did in v1. Verifiable-credential gating is new in DDO v5.

gated
  // Only these addresses may access it.
  .addCredentialAddresses(CredentialListTypes.ALLOW, ['0x0DB823218e337a...'])
  // And: a credential of this type, from an issuer you trust.
  .addRequestCredentials(CredentialListTypes.ALLOW, [ 
    { 
      type: 'VerifiableId', 
      format: 'jwt_vc_json', 
      policies: [{ policy: 'allowed-issuer', args: ['did:web:issuer.example'] }] 
    } 
  ]) 
  .setVcPolicies(CredentialListTypes.ALLOW, ['signature', 'not-before']) 
  // And: a presentation signed by the DID it names, holding at least one credential.
  .setVpPolicies(CredentialListTypes.ALLOW, [ 
    { policy: 'signature' }, 
    { policy: 'minimum-credentials', args: '1' } 
  ]) 

On a node with a policy server the address allow list is required, and it is the check that holds. Until the policy server enforces the requested credential type, the credential check stops only consumers who use a normal wallet: anyone who builds their own presentation passes it with a self-issued credential of another type. An allow list containing '*' therefore leaves no gate at all, so list the allowed addresses explicitly. See the known limitation.

See Credential-gated assets for the whole picture, including the consumer side.

Method reference

Metadata

setType · setName · setDescription · setDisplayTitle · setAuthor · setProvidedBy · setCopyrightHolder · setLicense · setAlgorithm · setContentLanguage · addTags · addCategories · addLinks · addAttachments · addAdditionalInformation

Services

addService · removeService

NFT

setNftData · setNftTokenName · setNftTokenSymbol · setNftTokenUri · setNftTokenTransferable · setNftTokenTemplate

Identity and gating

setIssuer · addCredentialAddresses · removeCredentialAddresses · addCredentialAccessList · addRequestCredentials · setVcPolicies · setVpPolicies · setCredentialMatchRules

Lifecycle

setLifecycleState · setOwner

Building

build · reset