Reorganize code.

lib/OID4Client.js

@@ -1,8 +1,10 @@
 /*!
- * Copyright (c) 2022-2024 Digital Bazaar, Inc. All rights reserved.
+ * Copyright (c) 2022-2025 Digital Bazaar, Inc. All rights reserved.
  */
-import {generateDIDProofJWT, robustDiscoverIssuer} from './util.js';
+import {createCredentialRequestsFromOffer} from './oid4vci/credentialOffer.js';
+import {generateDIDProofJWT} from './oid4vci/proofs.js';
 import {httpClient} from '@digitalbazaar/http-client';
+import {robustDiscoverIssuer} from './oid4vci/discovery.js';
 
 const GRANT_TYPES = new Map([
   ['preAuthorizedCode', 'urn:ietf:params:oauth:grant-type:pre-authorized_code']
@@ -66,7 +68,7 @@ export class OID4Client {
       if(!offer) {
         throw new TypeError('"credentialDefinition" must be an object.');
       }
-      requests = _createCredentialRequestsFromOffer({
+      requests = createCredentialRequestsFromOffer({
         issuerConfig, offer, format
       });
       if(requests.length > 1) {
@@ -97,7 +99,7 @@ export class OID4Client {
 
     const {issuerConfig, offer} = this;
     if(requests === undefined && offer) {
-      requests = _createCredentialRequestsFromOffer({
+      requests = createCredentialRequestsFromOffer({
         issuerConfig, offer, format
       });
     } else if(!(Array.isArray(requests) && requests.length > 0)) {
@@ -464,73 +466,3 @@ function _isPresentationRequired(error) {
   const errorType = error.data?.error;
   return error.status === 400 && errorType === 'presentation_required';
 }
-
-function _createCredentialRequestsFromOffer({
-  issuerConfig, offer, format
-}) {
-  // get any supported credential configurations from issuer config
-  const supported = _createSupportedCredentialsMap({issuerConfig});
-
-  // build requests from credentials identified in `offer` and remove any
-  // that do not match the given format
-  const credentials = offer.credential_configuration_ids ?? offer.credentials;
-  const requests = credentials.map(c => {
-    if(typeof c === 'string') {
-      // use supported credential config
-      return _getSupportedCredentialById({id: c, supported});
-    }
-    return c;
-  }).filter(r => r.format === format);
-
-  if(requests.length === 0) {
-    throw new Error(
-      `No supported credential(s) with format "${format}" found.`);
-  }
-
-  return requests;
-}
-
-function _createSupportedCredentialsMap({issuerConfig}) {
-  const {
-    credential_configurations_supported,
-    credentials_supported
-  } = issuerConfig;
-
-  let supported;
-  if(credential_configurations_supported &&
-    typeof credential_configurations_supported === 'object') {
-    supported = new Map(Object.entries(
-      issuerConfig.credential_configurations_supported));
-  } else if(Array.isArray(credentials_supported)) {
-    // handle legacy `credentials_supported` array
-    supported = new Map();
-    for(const entry of issuerConfig.credentials_supported) {
-      supported.set(entry.id, entry);
-    }
-  } else {
-    // no supported credentials from issuer config
-    supported = new Map();
-  }
-
-  return supported;
-}
-
-function _getSupportedCredentialById({id, supported}) {
-  const meta = supported.get(id);
-  if(!meta) {
-    throw new Error(`No supported credential "${id}" found.`);
-  }
-  const {format, credential_definition} = meta;
-  if(typeof format !== 'string') {
-    throw new Error(
-      `Invalid supported credential "${id}"; "format" not specified.`);
-  }
-  if(!(Array.isArray(credential_definition?.['@context']) &&
-    (Array.isArray(credential_definition?.types) ||
-    Array.isArray(credential_definition?.type)))) {
-    throw new Error(
-      `Invalid supported credential "${id}"; "credential_definition" not ` +
-      'fully specified.');
-  }
-  return {format, credential_definition};
-}

lib/convert.js → lib/convert/index.js

@@ -5,7 +5,7 @@ import {JSONPath} from 'jsonpath-plus';
 import jsonpointer from 'jsonpointer';
 import {
   validate as validateAuthorizationRequest
-} from './authorizationRequest.js';
+} from '../oid4vp/authorizationRequest.js';
 
 // converts a VPR to partial "authorization request"
 export function fromVpr({

lib/index.js

@@ -1,14 +1,18 @@
 /*!
  * Copyright (c) 2022-2025 Digital Bazaar, Inc. All rights reserved.
  */
-export * as oid4vp from './oid4vp.js';
+export * as oid4vp from './oid4vp/index.js';
 export {
   discoverIssuer,
-  generateDIDProofJWT,
+  robustDiscoverIssuer
+} from './oid4vci/discovery.js';
+export {
   getCredentialOffer,
-  parseCredentialOfferUrl,
-  robustDiscoverIssuer,
+  parseCredentialOfferUrl
+} from './oid4vci/credentialOffer.js';
+export {
   signJWT,
   selectJwk
 } from './util.js';
+export {generateDIDProofJWT} from './oid4vci/proofs.js';
 export {OID4Client} from './OID4Client.js';

lib/oid4vci/credentialOffer.js

@@ -0,0 +1,138 @@
+/*!
+ * Copyright (c) 2022-2025 Digital Bazaar, Inc. All rights reserved.
+ */
+import {assert, fetchJSON} from '../util.js';
+
+export function createCredentialRequestsFromOffer({
+  issuerConfig, offer, format
+} = {}) {
+  // get any supported credential configurations from issuer config
+  const supported = _createSupportedCredentialsMap({issuerConfig});
+
+  // build requests from credentials identified in `offer` and remove any
+  // that do not match the given format
+  const credentials = offer.credential_configuration_ids ?? offer.credentials;
+  const requests = credentials.map(c => {
+    if(typeof c === 'string') {
+      // use supported credential config
+      return _getSupportedCredentialById({id: c, supported});
+    }
+    return c;
+  }).filter(r => r.format === format);
+
+  if(requests.length === 0) {
+    throw new Error(
+      `No supported credential(s) with format "${format}" found.`);
+  }
+
+  return requests;
+}
+
+export async function getCredentialOffer({url, agent} = {}) {
+  const {protocol, searchParams} = new URL(url);
+  if(protocol !== 'openid-credential-offer:') {
+    throw new SyntaxError(
+      '"url" must express a URL with the ' +
+      '"openid-credential-offer" protocol.');
+  }
+  const offer = searchParams.get('credential_offer');
+  if(offer) {
+    return JSON.parse(offer);
+  }
+
+  // try to fetch offer from URL
+  const offerUrl = searchParams.get('credential_offer_uri');
+  if(!offerUrl) {
+    throw new SyntaxError(
+      'OID4VCI credential offer must have "credential_offer" or ' +
+      '"credential_offer_uri".');
+  }
+
+  if(!offerUrl.startsWith('https://')) {
+    const error = new Error(
+      `"credential_offer_uri" (${offerUrl}) must start with "https://".`);
+    error.name = 'NotSupportedError';
+    throw error;
+  }
+
+  const response = await fetchJSON({url: offerUrl, agent});
+  if(!response.data) {
+    const error = new Error(
+      `Credential offer fetched from "${offerUrl}" is not JSON.`);
+    error.name = 'DataError';
+    throw error;
+  }
+  return response.data;
+}
+
+export function parseCredentialOfferUrl({url} = {}) {
+  assert(url, 'url', 'string');
+
+  /* Parse URL, e.g.:
+
+  'openid-credential-offer://?' +
+    'credential_offer=%7B%22credential_issuer%22%3A%22https%3A%2F%2F' +
+    'localhost%3A18443%2Fexchangers%2Fz19t8xb568tNRD1zVm9R5diXR%2F' +
+    'exchanges%2Fz1ADs3ur2s9tm6JUW6CnTiyn3%22%2C%22credentials' +
+    '%22%3A%5B%7B%22format%22%3A%22ldp_vc%22%2C%22credential_definition' +
+    '%22%3A%7B%22%40context%22%3A%5B%22https%3A%2F%2Fwww.w3.org%2F2018%2F' +
+    'credentials%2Fv1%22%2C%22https%3A%2F%2Fwww.w3.org%2F2018%2F' +
+    'credentials%2Fexamples%2Fv1%22%5D%2C%22type%22%3A%5B%22' +
+    'VerifiableCredential%22%2C%22UniversityDegreeCredential' +
+    '%22%5D%7D%7D%5D%2C%22grants%22%3A%7B%22urn%3Aietf%3Aparams' +
+    '%3Aoauth%3Agrant-type%3Apre-authorized_code%22%3A%7B%22' +
+    'pre-authorized_code%22%3A%22z1AEvnk2cqeRM1Mfv75vzHSUo%22%7D%7D%7D';
+  */
+  const {protocol, searchParams} = new URL(url);
+  if(protocol !== 'openid-credential-offer:') {
+    throw new SyntaxError(
+      '"url" must express a URL with the ' +
+      '"openid-credential-offer" protocol.');
+  }
+  return JSON.parse(searchParams.get('credential_offer'));
+}
+
+function _createSupportedCredentialsMap({issuerConfig}) {
+  const {
+    credential_configurations_supported,
+    credentials_supported
+  } = issuerConfig;
+
+  let supported;
+  if(credential_configurations_supported &&
+    typeof credential_configurations_supported === 'object') {
+    supported = new Map(Object.entries(
+      issuerConfig.credential_configurations_supported));
+  } else if(Array.isArray(credentials_supported)) {
+    // handle legacy `credentials_supported` array
+    supported = new Map();
+    for(const entry of issuerConfig.credentials_supported) {
+      supported.set(entry.id, entry);
+    }
+  } else {
+    // no supported credentials from issuer config
+    supported = new Map();
+  }
+
+  return supported;
+}
+
+function _getSupportedCredentialById({id, supported}) {
+  const meta = supported.get(id);
+  if(!meta) {
+    throw new Error(`No supported credential "${id}" found.`);
+  }
+  const {format, credential_definition} = meta;
+  if(typeof format !== 'string') {
+    throw new Error(
+      `Invalid supported credential "${id}"; "format" not specified.`);
+  }
+  if(!(Array.isArray(credential_definition?.['@context']) &&
+    (Array.isArray(credential_definition?.types) ||
+    Array.isArray(credential_definition?.type)))) {
+    throw new Error(
+      `Invalid supported credential "${id}"; "credential_definition" not ` +
+      'fully specified.');
+  }
+  return {format, credential_definition};
+}