feat: Add support for enabling service worker feature (#1127)

* feat: Add support for enabling service worker feature in sandpack-bundler

* fix: actually set suffix correctly

* fix

* wip

* wip

* create story

* refactor

* docs

* format

* update

* add example

---------

Co-authored-by: Danilo Woznica <[email protected]>
Co-authored-by: codesandbox-bot <[email protected]>

Author: 3 people

.codesandbox/tasks.json

@@ -51,7 +51,7 @@
       "command": "yarn workspace @codesandbox/sandpack-react build"
     },
     "dev:website-docs": {
-      "name": "Documentation",
+      "name": "Dev: website docs",
       "command": "yarn dev:docs"
     },
     "dev:sandpack-react": {

sandpack-client/package.json

@@ -58,6 +58,7 @@
     "@codesandbox/nodebox": "0.1.8",
     "buffer": "^6.0.3",
     "dequal": "^2.0.2",
+    "mime-db": "^1.52.0",
     "outvariant": "1.4.0",
     "static-browser-server": "1.0.3"
   },

sandpack-client/src/clients/node/client.utils.ts

@@ -85,14 +85,14 @@ export const findStartScriptPackageJson = (
         }
 
         if (item.type === TokenType.Command && commandNotFoundYet) {
-          command = item.value;
+          command = item.value!;
         }
 
         if (
           item.type === TokenType.Argument ||
           (!commandNotFoundYet && item.type === TokenType.Command)
         ) {
-          args.push(item.value);
+          args.push(item.value!);
         }
 
         // TODO: support TokenType.AND, TokenType.OR, TokenType.PIPE

sandpack-client/src/clients/runtime/index.ts

@@ -23,16 +23,20 @@ import { SandpackClient } from "../base";
 
 import Protocol from "./file-resolver-protocol";
 import { IFrameProtocol } from "./iframe-protocol";
-import type { SandpackRuntimeMessage } from "./types";
-import { getTemplate } from "./utils";
+import { EXTENSIONS_MAP } from "./mime";
+import type { IPreviewRequestMessage, IPreviewResponseMessage } from "./types";
+import { CHANNEL_NAME, type SandpackRuntimeMessage } from "./types";
+import { getExtension, getTemplate } from "./utils";
+
+const SUFFIX_PLACEHOLDER = "-{{suffix}}";
 
 const BUNDLER_URL =
   process.env.CODESANDBOX_ENV === "development"
     ? "http://localhost:3000/"
     : `https://${process.env.PACKAGE_VERSION?.replace(
         /\./g,
         "-"
-      )}-sandpack.codesandbox.io/`;
+      )}${SUFFIX_PLACEHOLDER}-sandpack.codesandbox.io/`;
 
 export class SandpackRuntime extends SandpackClient {
   fileResolverProtocol?: Protocol;
@@ -62,6 +66,15 @@ export class SandpackRuntime extends SandpackClient {
         `?cache=${Date.now()}`;
     }
 
+    const suffixes: string[] = [];
+    if (options.experimental_enableServiceWorker) {
+      suffixes.push(Math.random().toString(36).slice(4));
+    }
+    this.bundlerURL = this.bundlerURL.replace(
+      SUFFIX_PLACEHOLDER,
+      suffixes.length ? `-${suffixes.join("-")}` : ""
+    );
+
     this.bundlerState = undefined;
     this.errors = [];
     this.status = "initializing";
@@ -153,6 +166,89 @@ export class SandpackRuntime extends SandpackClient {
         }
       }
     );
+
+    if (options.experimental_enableServiceWorker) {
+      this.serviceWorkerHandshake();
+    }
+  }
+
+  private serviceWorkerHandshake() {
+    const channel = new MessageChannel();
+
+    const iframeContentWindow = this.iframe.contentWindow;
+    if (!iframeContentWindow) {
+      throw new Error("Could not get iframe contentWindow");
+    }
+
+    const port = channel.port1;
+    port.onmessage = (evt: MessageEvent) => {
+      if (typeof evt.data === "object" && evt.data.$channel === CHANNEL_NAME) {
+        switch (evt.data.$type) {
+          case "preview/ready":
+            // no op for now
+            break;
+          case "preview/request":
+            this.handleWorkerRequest(evt.data, port);
+
+            break;
+        }
+      }
+    };
+
+    this.iframe.onload = () => {
+      const initMsg = {
+        $channel: CHANNEL_NAME,
+        $type: "preview/init",
+      };
+
+      iframeContentWindow.postMessage(initMsg, "*", [channel.port2]);
+    };
+  }
+
+  private handleWorkerRequest(
+    request: IPreviewRequestMessage,
+    port: MessagePort
+  ) {
+    try {
+      const filepath = new URL(request.url, this.bundlerURL).pathname;
+
+      const headers: Record<string, string> = {};
+
+      const files = this.getFiles();
+      const body = files[filepath].code;
+
+      if (!headers["Content-Type"]) {
+        const extension = getExtension(filepath);
+        const foundMimetype = EXTENSIONS_MAP.get(extension);
+        if (foundMimetype) {
+          headers["Content-Type"] = foundMimetype;
+        }
+      }
+
+      const responseMessage: IPreviewResponseMessage = {
+        $channel: CHANNEL_NAME,
+        $type: "preview/response",
+        id: request.id,
+        headers,
+        status: 200,
+        body,
+      };
+
+      port.postMessage(responseMessage);
+    } catch (err) {
+      const responseMessage: IPreviewResponseMessage = {
+        $channel: CHANNEL_NAME,
+        $type: "preview/response",
+        id: request.id,
+        headers: {
+          "Content-Type": "text/html; charset=utf-8",
+        },
+        status: 404,
+        body: "File not found",
+      };
+
+      port.postMessage(responseMessage);
+    }
   }
 
   public setLocationURLIntoIFrame(): void {
@@ -240,6 +336,8 @@ export class SandpackRuntime extends SandpackClient {
       hasFileResolver: Boolean(this.options.fileResolver),
       disableDependencyPreprocessing:
         this.sandboxSetup.disableDependencyPreprocessing,
+      experimental_enableServiceWorker:
+        this.options.experimental_enableServiceWorker,
       template:
         this.sandboxSetup.template ||
         getTemplate(packageJSON, normalizedModules),

sandpack-client/src/clients/runtime/mime.ts

@@ -0,0 +1,22 @@
+import mimeDB from "mime-db";
+
+const extensionMap = new Map<string, string>();
+const entries = Object.entries(mimeDB);
+for (const [mimetype, entry] of entries) {
+  // eslint-disable-next-line
+  // @ts-ignore
+  if (!entry.extensions) {
+    continue;
+  }
+
+  // eslint-disable-next-line
+  // @ts-ignore
+  const extensions = entry.extensions as string[];
+  if (extensions.length) {
+    for (const ext of extensions) {
+      extensionMap.set(ext, mimetype);
+    }
+  }
+}
+
+export const EXTENSIONS_MAP = extensionMap;

sandpack-client/src/clients/runtime/types.ts

@@ -68,6 +68,7 @@ export type SandpackRuntimeMessage = BaseSandpackMessage &
         externalResources: string[];
         hasFileResolver: boolean;
         disableDependencyPreprocessing?: boolean;
+        experimental_enableServiceWorker?: boolean;
         template?: string | SandpackTemplate;
         showOpenInCodeSandbox: boolean;
         showErrorScreen: boolean;
@@ -123,3 +124,21 @@ export type SandpackRuntimeMessage = BaseSandpackMessage &
             };
       }
   );
+export const CHANNEL_NAME = "$CSB_RELAY";
+
+export interface IPreviewRequestMessage {
+  $channel: typeof CHANNEL_NAME;
+  $type: "preview/request";
+  id: string;
+  method: string;
+  url: string;
+}
+
+export interface IPreviewResponseMessage {
+  $channel: typeof CHANNEL_NAME;
+  $type: "preview/response";
+  id: string;
+  status: number;
+  headers: Record<string, string>;
+  body: string | Uint8Array;
+}

sandpack-client/src/clients/runtime/utils.ts

@@ -180,3 +180,13 @@ export function getTemplate(
 
   return undefined;
 }
+
+export function getExtension(filepath: string): string {
+  const parts = filepath.split(".");
+  if (parts.length <= 1) {
+    return "";
+  } else {
+    const ext = parts[parts.length - 1];
+    return ext;
+  }
+}

sandpack-client/src/types.ts

@@ -70,6 +70,11 @@ export interface ClientOptions {
    * and unlock a few capabilities
    */
   teamId?: string;
+
+  /**
+   * Enable the service worker feature for sandpack-bundler
+   */
+  experimental_enableServiceWorker?: boolean;
 }
 
 export interface SandboxSetup {

sandpack-react/package.json

@@ -88,7 +88,6 @@
     "astring": "^1.8.4",
     "babel-loader": "^7.1.5",
     "rollup-plugin-filesize": "^10.0.0",
-    "rollup-plugin-preserve-directives": "^0.4.0",
     "storybook": "^7.5.1",
     "typescript": "^5.2.2"
   },

sandpack-react/rollup.config.js

@@ -3,7 +3,6 @@ const commonjs = require("@rollup/plugin-commonjs");
 const replace = require("@rollup/plugin-replace");
 const typescript = require("@rollup/plugin-typescript");
 const filesize = require("rollup-plugin-filesize");
-const { preserveDirectives } = require("rollup-plugin-preserve-directives");
 
 const pkg = require("./package.json");
 const generateUnstyledTypes = require("./scripts/rollup-generate-unstyled-types");
@@ -32,8 +31,7 @@ const configBase = [
         },
       }),
       typescript({ tsconfig: "./tsconfig.json" }),
-      filesize(),
-      preserveDirectives({ suppressPreserveModulesWarning: true })
+      filesize()
     ),
     output: [
       {