Websocket backend

bin/bin.ts

@@ -0,0 +1,104 @@
+#!/usr/bin/ts-node
+/*!
+   Copyright 2018 Propel http://propel.site/.  All rights reserved.
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+ */
+
+/**
+ * This file contains "propel" command which can be used
+ * to start a local web server and execute codes on Node.js
+ * from notebook (browser).
+ */
+
+import { fork, isMaster } from "cluster";
+import { readFileSync } from "fs";
+import * as opn from "opn";
+import * as path from "path";
+import { TextDecoder } from "util";
+import * as vm from "vm";
+import * as WebSocket from "ws";
+import { ClusterRPC } from "../src/rpc";
+import { createHTTPServer } from "./server";
+
+// Constants
+const PORT = 8081;
+const sandboxSrc = path.join(__dirname, "../build/website/sandbox.js");
+
+if (isMaster) {
+  // Start a websocket server in master process.
+  const server = createHTTPServer();
+  const wss = new WebSocket.Server({ server });
+
+  wss.on("connection", (ws: WebSocket) => {
+    // For now, let's create a new process for each connection and load
+    // sandbox.ts in there.
+    const worker = fork();
+    // Route all messages from child process to client.
+    worker.on("message", msg => {
+      const message = JSON.stringify(msg);
+      ws.send(message);
+    });
+    // Handle worker exit.
+    worker.on("exit", () => {
+      console.log("[%s] Worker exited.", worker.process.pid);
+      if (ws.readyStatus === ws.OPEN) {
+        ws.close();
+      }
+    });
+    // Route all valid messages to the child process.
+    ws.on("message", rawData => {
+      try {
+        const data = JSON.parse(String(rawData));
+        worker.send(data);
+      } catch (e) {
+        console.error(e);
+      }
+    });
+    // Kill a child process whenever user disconnects.
+    ws.on("close", () => {
+      worker.kill();
+    });
+  });
+
+  server.listen(PORT, () => {
+    console.log("Propel server started on port %s.", PORT);
+    const wsUrl = `ws://localhost:${PORT}`;
+    opn(`http://localhost:${PORT}/#/?ws=${wsUrl}`);
+  });
+} else {
+  console.log("[%s] Worker started.", process.pid);
+  const sandboxCode = readFileSync(sandboxSrc).toString();
+  const clusterRPC = new ClusterRPC(process);
+  const sandbox = {
+    Buffer,
+    TextDecoder,
+    clusterRPC,
+    process: {
+      cwd: process.cwd,
+      env: process.env,
+      platform: process.platform
+    },
+    require: safeRequire
+  };
+  vm.createContext(sandbox);
+  vm.runInContext(sandboxCode, sandbox);
+}
+
+function safeRequire(moduleName) {
+  const allowedModules = ["url", "http", "https"];
+  if (allowedModules.indexOf(moduleName) < 0) {
+    console.log(moduleName);
+    throw new Error("Calling require is forbidden.");
+  }
+  return require(moduleName);
+}

bin/server.ts

@@ -0,0 +1,50 @@
+/*!
+   Copyright 2018 Propel http://propel.site/.  All rights reserved.
+   Licensed under the Apache License, Version 2.0 (the "License");
+   you may not use this file except in compliance with the License.
+   You may obtain a copy of the License at
+
+   http://www.apache.org/licenses/LICENSE-2.0
+
+   Unless required by applicable law or agreed to in writing, software
+   distributed under the License is distributed on an "AS IS" BASIS,
+   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+   See the License for the specific language governing permissions and
+   limitations under the License.
+ */
+
+import * as fs from "fs";
+import * as http from "http";
+import * as mime from "mime";
+import * as path from "path";
+import * as url from "url";
+
+const basePath = path.join(__dirname, "../build/website");
+const index = path.join(basePath, "index.html");
+
+// create a simple HTTP server to serve static files.
+export function createHTTPServer() {
+  const server = http.createServer((req, res) => {
+    const reqUrl = url.parse(req.url, true);
+    const filePath = path.join(basePath, reqUrl.pathname);
+    if (!filePath.startsWith(basePath)) {
+      res.writeHead(403, { "Content-Type": "text/html; charset=utf-8" });
+      res.end("Access denied.");
+      return;
+    }
+    fs.stat(filePath, (err, stat) => {
+      let finalPath = filePath;
+      if (err && err.code === "ENOENT" || stat.isDirectory()) {
+        finalPath = index;
+      } else if (err) {
+        res.writeHead(500, { "Content-Type": "text/html; charset=utf-8" });
+        res.end(`Unexpected server error occurred. [#${err.code}]`);
+        return;
+      }
+      res.writeHead(200, { "Content-Type": mime.getType(finalPath) });
+      const stream = fs.createReadStream(finalPath);
+      stream.pipe(res);
+    });
+  });
+  return server;
+}

package.json

@@ -18,15 +18,20 @@
   "devDependencies": {
     "@types/acorn": "^4.0.3",
     "@types/codemirror": "0.0.51",
+    "@types/history": "^4.6.2",
     "@types/node": "^8.9.4",
     "acorn": "^5.5.0",
     "codemirror": "^5.35.0",
     "he": "^1.1.1",
+    "history": "^4.7.2",
+    "mime": "^2.3.1",
     "ncp": "^2.0.0",
     "node-fetch": "^1.7.3",
     "node-sass": "^4.9.0",
+    "opn": "^5.3.0",
     "parcel-bundler": "^1.8.1",
     "parcel-plugin-markdown": "^0.3.1",
+    "path-to-regexp": "^2.2.1",
     "preact": "^8.2.7",
     "prettier": "^1.12.1",
     "puppeteer": "^0.13.0",
@@ -43,7 +48,7 @@
     "tslint-no-circular-imports": "^0.3.0",
     "typescript": "^2.8.3",
     "vega-lib": "^3.2.1",
-    "ws": "^5.0.0"
+    "ws": "^5.2.0"
   },
   "browserslist": [
     ">5%"