Add network info fetching from WS

Author: zivkovicmilos

jest.config.js

@@ -2,4 +2,5 @@
 module.exports = {
   preset: 'ts-jest',
   testEnvironment: 'node',
+  modulePathIgnorePatterns: ['bin', 'node_modules'],
 };

package.json

@@ -13,6 +13,7 @@
   "devDependencies": {
     "@types/jest": "^29.5.0",
     "@types/node": "^18.15.11",
+    "@types/ws": "^8.5.4",
     "@typescript-eslint/eslint-plugin": "^5.57.0",
     "@typescript-eslint/parser": "^5.57.0",
     "eslint": "^8.37.0",
@@ -25,7 +26,8 @@
     "typescript": "^5.0.3"
   },
   "dependencies": {
-    "axios": "^1.3.4"
+    "axios": "^1.3.4",
+    "ws": "^8.13.0"
   },
   "scripts": {
     "tsc": "tsc",

src/provider/test/ws.test.ts

@@ -0,0 +1,48 @@
+import { NetworkInfo } from '../types';
+import { WebSocketServer } from 'ws';
+import { WSProvider } from '../websocket/websocket';
+import { newResponse } from '../spec/utility';
+
+describe('WS Provider', () => {
+  const wsPort = 8545;
+  const wsHost = 'localhost';
+  const wsURL = `ws://${wsHost}:${wsPort}`;
+
+  let wsProvider: WSProvider;
+  let server: WebSocketServer;
+
+  beforeEach(async () => {
+    server = new WebSocketServer({
+      host: wsHost,
+      port: wsPort,
+    });
+    wsProvider = new WSProvider(wsURL);
+  });
+
+  afterEach(() => {
+    wsProvider.closeConnection();
+    server.close();
+  });
+
+  test('getNetwork', async () => {
+    const mockInfo: NetworkInfo = {
+      listening: false,
+      listeners: [],
+      n_peers: '0',
+      peers: [],
+    };
+
+    server.on('connection', (socket) => {
+      socket.on('message', (data) => {
+        const request = JSON.parse(data.toString());
+        const response = newResponse<NetworkInfo>(mockInfo);
+        response.id = request.id;
+
+        socket.send(JSON.stringify(response));
+      });
+    });
+
+    const info = await wsProvider.getNetwork();
+    expect(info).toEqual(mockInfo);
+  });
+});

src/provider/websocket/websocket.ts

@@ -1,6 +1,9 @@
 import { Provider } from '../provider';
 import { ConsensusParams, NetworkInfo, Status } from '../types';
 import { RPCRequest, RPCResponse } from '../spec/jsonrpc';
+import { newRequest } from '../spec/utility';
+import { ConsensusEndpoint } from '../endpoints';
+import { WebSocket } from 'ws';
 
 /**
  * Provider based on WS JSON-RPC HTTP requests
@@ -24,8 +27,9 @@ export class WSProvider implements Provider {
    */
   constructor(baseURL: string, requestTimeout?: number) {
     this.ws = new WebSocket(baseURL);
+
     this.ws.addEventListener('message', (event) => {
-      const response = JSON.parse(event.data) as RPCResponse<any>;
+      const response = JSON.parse(event.data as string) as RPCResponse<any>;
       const request = this.requestMap.get(response.id);
       if (request) {
         this.requestMap.delete(response.id);
@@ -39,15 +43,28 @@ export class WSProvider implements Provider {
     });
   }
 
+  /**
+   * Closes the WS connection. Required when done working
+   * with the WS provider
+   */
+  closeConnection() {
+    this.ws.close();
+  }
+
   /**
    * Sends a request to the WS connection, and resolves
    * upon receiving the response
    * @param {RPCRequest} request the RPC request
    * @returns {Promise<RPCResponse<any>>} the RPC response
    */
-  sendRequest(request: RPCRequest): Promise<RPCResponse<any>> {
+  async sendRequest<Result>(request: RPCRequest): Promise<RPCResponse<Result>> {
+    // Make sure the connection is open
+    if (this.ws.readyState != WebSocket.OPEN) {
+      await this.waitForOpenConnection();
+    }
+
     // The promise will resolve as soon as the response is received
-    const promise = new Promise<RPCResponse<any>>((resolve, reject) => {
+    const promise = new Promise<RPCResponse<Result>>((resolve, reject) => {
       const timeout = setTimeout(() => {
         this.requestMap.delete(request.id);
 
@@ -62,6 +79,52 @@ export class WSProvider implements Provider {
     return promise;
   }
 
+  /**
+   * Parses the result from the response
+   * @param {RPCResponse<Result>} response the response to be parsed
+   * @returns {Result} the result of the response
+   */
+  parseResponse<Result>(response: RPCResponse<Result>): Result {
+    if (!response) {
+      throw new Error('invalid response');
+    }
+
+    if (response.error) {
+      throw new Error(response.error?.message);
+    }
+
+    if (!response.result) {
+      throw new Error('invalid response returned');
+    }
+
+    return response.result;
+  }
+
+  /**
+   * Waits for the WS connection to be established
+   * @returns {Promise<null>} resolve / reject indicating success
+   */
+  waitForOpenConnection = () => {
+    return new Promise((resolve, reject) => {
+      const maxNumberOfAttempts = 10;
+      const intervalTime = 200; //ms
+
+      let currentAttempt = 0;
+      const interval = setInterval(() => {
+        if (this.ws.readyState === WebSocket.OPEN) {
+          clearInterval(interval);
+          resolve(null);
+        }
+
+        currentAttempt++;
+        if (currentAttempt > maxNumberOfAttempts - 1) {
+          clearInterval(interval);
+          reject(new Error('Maximum number of attempts exceeded'));
+        }
+      }, intervalTime);
+    });
+  };
+
   estimateGas(tx: any): Promise<number> {
     return Promise.reject('implement me');
   }
@@ -94,8 +157,12 @@ export class WSProvider implements Provider {
     return Promise.reject('implement me');
   }
 
-  getNetwork(): Promise<NetworkInfo> {
-    return Promise.reject('implement me');
+  async getNetwork(): Promise<NetworkInfo> {
+    const response = await this.sendRequest<NetworkInfo>(
+      newRequest(ConsensusEndpoint.NET_INFO)
+    );
+
+    return this.parseResponse<NetworkInfo>(response);
   }
 
   getSequence(address: string, height?: number): Promise<number> {

yarn.lock

@@ -727,6 +727,13 @@
   resolved "https://registry.yarnpkg.com/@types/stack-utils/-/stack-utils-2.0.1.tgz#20f18294f797f2209b5f65c8e3b5c8e8261d127c"
   integrity sha512-Hl219/BT5fLAaz6NDkSuhzasy49dwQS/DSdu4MdggFB8zcXv7vflBI3xp7FEmkmdDkBUI2bPUNeMttp2knYdxw==
 
+"@types/ws@^8.5.4":
+  version "8.5.4"
+  resolved "https://registry.yarnpkg.com/@types/ws/-/ws-8.5.4.tgz#bb10e36116d6e570dd943735f86c933c1587b8a5"
+  integrity sha512-zdQDHKUgcX/zBc4GrwsE/7dVdAD8JR4EuiAXiiUhhfyIJXXb2+PrGshFyeXWQPMmmZ2XxgaqclgpIC7eTXc1mg==
+  dependencies:
+    "@types/node" "*"
+
 "@types/yargs-parser@*":
   version "21.0.0"
   resolved "https://registry.yarnpkg.com/@types/yargs-parser/-/yargs-parser-21.0.0.tgz#0c60e537fa790f5f9472ed2776c2b71ec117351b"
@@ -2850,6 +2857,11 @@ write-file-atomic@^4.0.2:
     imurmurhash "^0.1.4"
     signal-exit "^3.0.7"
 
+ws@^8.13.0:
+  version "8.13.0"
+  resolved "https://registry.yarnpkg.com/ws/-/ws-8.13.0.tgz#9a9fb92f93cf41512a0735c8f4dd09b8a1211cd0"
+  integrity sha512-x9vcZYTrFPC7aSIbj7sRCYo7L/Xb8Iy+pW0ng0wt2vCJv7M9HOMy0UoN3rr+IFC7hb7vXoqS+P9ktyLLLhO+LA==
+
 y18n@^5.0.5:
   version "5.0.8"
   resolved "https://registry.yarnpkg.com/y18n/-/y18n-5.0.8.tgz#7f4934d0f7ca8c56f95314939ddcd2dd91ce1d55"