actionhero/src/servers/websocket.ts

The reusable, scalable, and quick node.js API server for stateless and stateful applications

import * as Primus from "primus";
import * as fs from "fs";
import * as path from "path";
import * as util from "util";
import * as uuid from "uuid";
import { api, config, utils, log, Server, Connection } from "../index";

export class WebSocketServer extends Server {
  server: Primus;

  constructor() {
    super();
    this.type = "websocket";

    this.attributes = {
      canChat: true,
      logConnections: true,
      logExits: true,
      sendWelcomeMessage: true,
      verbs: [
        "quit",
        "exit",
        "documentation",
        "roomAdd",
        "roomLeave",
        "roomView",
        "detailsView",
        "say",
      ],
    };
  }

  async initialize() {
    // we rely on the web server :D
  }

  async start() {
    const webserver = api.servers.servers.web;
    if (!webserver) {
      throw new Error(`websocket server requires web server to be enabled`);
    }

    this.server = new Primus(webserver.server, this.config.server);

    this.writeClientJS();

    this.server.on("connection", (rawConnection) => {
      this.handleConnection(rawConnection);
    });

    this.server.on("disconnection", (rawConnection) => {
      this.handleDisconnection(rawConnection);
    });

    this.log(
      `webSockets bound to ${webserver.config.bindIP}:${webserver.config.port}`,
      "debug",
    );

    this.on("connection", (connection: Connection) => {
      connection.rawConnection.on("data", (data: Record<string, any>) => {
        this.handleData(connection, data);
      });
    });

    this.on("actionComplete", (data) => {
      if (data.toRender !== false) {
        data.connection.response.messageId = data.messageId;
        this.sendMessage(data.connection, data.response, data.messageId);
      }
    });
  }

  async stop() {
    if (!this.server) return;

    if (this.config.destroyClientsOnShutdown === true) {
      this.connections().forEach((connection: Connection) => {
        connection.destroy();
      });
    }

    //@ts-ignore
    this.server.destroy();
  }

  async sendMessage(
    connection: Connection,
    message: Record<string, any>,
    messageId: string,
  ) {
    if (message.error) {
      message.error = config.errors.serializers.servers.websocket(
        message.error,
      );
    }

    if (!message.context) {
      message.context = "response";
    }
    if (!messageId) {
      messageId = connection.messageId;
    }
    if (message.context === "response" && !message.messageId) {
      message.messageId = messageId;
    }

    connection.rawConnection.write(message);
  }

  async sendFile(
    connection: Connection,
    error: NodeJS.ErrnoException,
    fileStream: any,
    mime: string,
    length: number,
    lastModified: Date,
  ) {
    const messageId = connection.messageId;
    let content = "";
    const response = {
      error: error,
      content: null as string,
      mime: mime,
      length: length,
      lastModified: lastModified,
    };

    try {
      if (!error) {
        fileStream.on("data", (d: string) => {
          content += d;
        });
        fileStream.on("end", () => {
          response.content = content;
          this.sendMessage(connection, response, messageId);
        });
      } else {
        this.sendMessage(connection, response, messageId);
      }
    } catch (e) {
      this.log(e, "warning");
      this.sendMessage(connection, response, messageId);
    }
  }

  //@ts-ignore
  goodbye(connection: Connection) {
    connection.rawConnection.end();
  }

  compileActionheroWebsocketClientJS() {
    let ahClientSource = fs
      .readFileSync(
        path.join(__dirname, "/../../client/ActionheroWebsocketClient.js"),
      )
      .toString();
    const url = this.config.clientUrl;
    ahClientSource = ahClientSource.replace(/%%URL%%/g, url);
    const defaults: {
      [key: string]: any;
    } = {};

    for (const i in this.config.client) {
      defaults[i] = this.config.client[i];
    }

    defaults.url = url;
    let defaultsString = util.inspect(defaults);
    defaultsString = defaultsString.replace(
      "'window.location.origin'",
      "window.location.origin",
    );
    ahClientSource = ahClientSource.replace(
      "%%DEFAULTS%%",
      "return " + defaultsString,
    );

    return ahClientSource;
  }

  renderClientJS() {
    const libSource = api.servers.servers.websocket.server.library();
    let ahClientSource = this.compileActionheroWebsocketClientJS();
    ahClientSource =
      ";;;\r\n" +
      "(function(exports){ \r\n" +
      ahClientSource +
      "\r\n" +
      "exports.ActionheroWebsocketClient = ActionheroWebsocketClient; \r\n" +
      "exports.ActionheroWebsocketClient = ActionheroWebsocketClient; \r\n" +
      "})(typeof exports === 'undefined' ? window : exports);";

    return libSource + "\r\n\r\n\r\n" + ahClientSource;
  }

  writeClientJS() {
    if (
      !config.general.paths.public ||
      config.general.paths.public.length === 0
    ) {
      return;
    }

    if (this.config.clientJsPath && this.config.clientJsName) {
      const clientJSPath = path.normalize(
        config.general.paths.public[0] +
          path.sep +
          this.config.clientJsPath +
          path.sep,
      );
      const clientJSName = this.config.clientJsName;
      const clientJSFullPath = clientJSPath + clientJSName;
      try {
        if (!fs.existsSync(clientJSPath)) {
          fs.mkdirSync(clientJSPath, { recursive: true });
        }
        fs.writeFileSync(clientJSFullPath + ".js", this.renderClientJS());
        log(`wrote ${clientJSFullPath}.js`, "debug");
      } catch (e) {
        log("Cannot write client-side JS for websocket server:", "alert", e);
        throw e;
      }
    }
  }

  handleConnection(rawConnection: Primus.Spark) {
    const fingerprint =
      rawConnection.query[config.web.fingerprintOptions.cookieKey];
    const { ip, port } = utils.parseHeadersForClientAddress(
      rawConnection.headers,
    );

    this.buildConnection({
      rawConnection: rawConnection,
      remoteAddress: ip || rawConnection.address.ip,
      remotePort: port || rawConnection.address.port,
      fingerprint: fingerprint,
    });
  }

  handleDisconnection(rawConnection: Primus.Spark) {
    const connections = this.connections();
    for (const i in connections) {
      if (
        connections[i] &&
        rawConnection.id === connections[i].rawConnection.id
      ) {
        connections[i].destroy();
        break;
      }
    }
  }

  async handleData(connection: Connection, data: Record<string, any>) {
    const verb = data.event;
    delete data.event;

    connection.messageId = data.messageId || uuid.v4();
    delete data.messageId;
    connection.params = {};

    if (verb === "action") {
      for (const v in data.params) {
        connection.params[v] = data.params[v];
      }
      connection.error = null;
      connection.response = {};
      return this.processAction(connection);
    }

    if (verb === "file") {
      connection.params = {
        file: data.file,
      };
      return this.processFile(connection);
    }

    const words = [];
    let message;
    if (data.room) {
      words.push(data.room);
      delete data.room;
    }
    for (const i in data) {
      words.push(data[i]);
    }
    const messageId = connection.messageId;
    try {
      const data = await connection.verbs(verb, words);
      message = { status: "OK", context: "response", data: data };
      return this.sendMessage(connection, message, messageId);
    } catch (error) {
      const formattedError = error.toString();
      message = {
        status: formattedError,
        error: formattedError,
        context: "response",
        data: data,
      };
      return this.sendMessage(connection, message, messageId);
    }
  }
}