feat: add support for DID ETHR

License: MIT
Signed-off-by: Vaibhav Saini <[email protected]>

package.json

@@ -77,6 +77,8 @@
   },
   "dependencies": {
     "did-resolver": "0.0.6",
+    "ethjs-provider-http": "^0.1.6",
+    "ethr-did-resolver": "^0.2.0",
     "idm-signatures": "^0.1.0",
     "ipfs": "git://github.com/satazor/js-ipfs.git#ipfs-camp",
     "ipid-did-resolver": "^0.1.2",

src/did-resolver.js

@@ -1,7 +1,13 @@
 import registerIpidResolver from 'ipid-did-resolver';
+import registerEthrDidToResolver from 'ethr-did-resolver';
 import resolveDid from 'did-resolver';
+
 import Ipfs from 'ipfs';
-import { UnavailableIpfsError } from './errors';
+import { UnavailableIpfsError, UnavailableWeb3Error } from './errors';
+
+const HttpProvider = require('ethjs-provider-http');
+const WEB3_WEBSOCKET_ADDR = 'wss://rinkeby.infura.io/ws/v3/b94d9fecfb0f4d5697929ee98607c9f5';
+const REGISTRY_ADDRESS = '0xdCa7EF03e98e0DC2B855bE647C39ABe984fcF21B';
 
 const createIpfs = (ipfs) => {
     if (ipfs) {
@@ -33,12 +39,54 @@ const createIpfs = (ipfs) => {
     });
 };
 
-const setupDidResolver = async (options) => {
+const createEthProvider = (web3, websocketAddress = WEB3_WEBSOCKET_ADDR) => new Promise((resolve, reject) => {
+    try {
+        if (web3) {
+            if (typeof web3.sendAsync !== 'function') {
+                throw new UnavailableWeb3Error();
+            }
+
+            return resolve(web3);
+        }
+
+        web3 = new HttpProvider(websocketAddress);
+
+        return resolve(web3);
+    } catch (err) {
+        reject(err);
+    }
+});
+
+const setupDidResolver = async (options, method) => {
+    switch (method) {
+    case 'ipid':
+        await setupIpidResolver(options);
+        break;
+
+    case 'ethr':
+        await setupEthrResolver(options);
+        break;
+
+    default:
+        await setupIpidResolver(options);
+    }
+
+    return resolveDid;
+};
+
+const setupIpidResolver = async (options) => {
     const ipfsNode = await createIpfs(options.ipfs);
 
     registerIpidResolver(ipfsNode);
+};
 
-    return resolveDid;
+const setupEthrResolver = async (provider, websocketAddress) => {
+    const newProvider = createEthProvider(provider, websocketAddress);
+
+    registerEthrDidToResolver.default({
+        newProvider,
+        registry: REGISTRY_ADDRESS,
+    });
 };
 
 export default setupDidResolver;

src/errors.js

@@ -35,3 +35,9 @@ export class UnavailableIpfsError extends BaseError {
         super('IPFS node is unavailable', 'IPFS_UNAVAILABLE');
     }
 }
+
+export class UnavailableWeb3Error extends BaseError {
+    constructor() {
+        super('Web3 node is unavailable', 'WEB3_UNAVAILABLE');
+    }
+}