Support use of local CORS proxy when serving the wasm deployments

wasm/.gitignore

@@ -11,6 +11,6 @@ package-lock.json
 cockle/
 lite-deploy/package.json
 recipe/em-forge-recipes/
-serve/*/
+serve/dist/*/
 test/assets/*/
 test/lib/

wasm/CMakeLists.txt

@@ -7,17 +7,15 @@ option(USE_COCKLE_RELEASE "Use latest cockle release rather than repo main branc
 add_subdirectory(recipe)
 add_subdirectory(cockle-deploy)
 add_subdirectory(lite-deploy)
+add_subdirectory(serve)
 add_subdirectory(test)
 
 # Build everything (package, cockle and lite deployments, tests).
-add_custom_target(build ALL DEPENDS build-recipe build-cockle build-lite build-test)
+add_custom_target(build ALL DEPENDS build-recipe build-cockle build-lite build-serve build-test)
 
 # Rebuild after change in C++ code.
 add_custom_target(rebuild DEPENDS rebuild-recipe rebuild-cockle rebuild-lite rebuild-test)
 
-# Serve both cockle and JupyterLite deployments.
-add_custom_target(serve COMMAND npx static-handler --cors --coop --coep --corp serve)
-
 if (USE_COCKLE_RELEASE)
     execute_process(COMMAND npm view @jupyterlite/cockle version OUTPUT_VARIABLE COCKLE_BRANCH)
     set(COCKLE_BRANCH "v${COCKLE_BRANCH}")

wasm/README.md

@@ -65,6 +65,15 @@ Note that the `source` for the `git2cpp` package is the local filesystem rather
 version number of the current Emscripten-forge recipe rather than the version of the local `git2cpp`
 source code which can be checked using `git2cpp -v` at the `cockle`/`terminal` command line.
 
+If you want to remotely access git servers using `git2cpp` subcommands such as `clone`, `fetch`
+and `push`, then serve with a local CORS proxy using:
+
+```bash
+make serve-with-cors
+```
+
+which will use the CORS proxy on `http://localhost:8881/`.
+
 ## Rebuild
 
 After making changes to the local `git2cpp` source code you can rebuild the WebAssembly package,

wasm/cockle-deploy/CMakeLists.txt

@@ -3,7 +3,7 @@ project(git2cpp-wasm-cockle-deploy)
 
 include("../common.cmake")
 
-set(SERVE_DIR "../serve/cockle")
+set(SERVE_DIR "../serve/dist/cockle")
 
 add_custom_target(build-cockle
     DEPENDS build-recipe cockle

wasm/cockle-deploy/package.json

@@ -3,11 +3,11 @@
   "scripts": {
     "build": "rspack build",
     "postbuild": "npm run postbuild:wasm && npm run postbuild:index",
-    "postbuild:wasm": "node node_modules/@jupyterlite/cockle/lib/tools/prepare_wasm.js --copy ../serve/cockle/",
-    "postbuild:index": "cp assets/index.html ../serve/cockle/"
+    "postbuild:wasm": "node node_modules/@jupyterlite/cockle/lib/tools/prepare_wasm.js --copy ../serve/dist/cockle/",
+    "postbuild:index": "cp assets/index.html ../serve/dist/cockle/"
   },
-  "main": "../serve/cockle/index.js",
-  "types": "../serve/cockle/index.d.ts",
+  "main": "../serve/dist/cockle/index.js",
+  "types": "../serve/dist/cockle/index.d.ts",
   "keywords": [],
   "author": "",
   "license": "ISC",

wasm/cockle-deploy/rspack.config.js

@@ -24,6 +24,6 @@ module.exports = {
   },
   output: {
     filename: 'bundle.js',
-    path: path.resolve(__dirname, '../serve/cockle'),
+    path: path.resolve(__dirname, '../serve/dist/cockle'),
   }
 };

wasm/cockle-deploy/src/defs.ts

@@ -6,5 +6,6 @@ export namespace IDeployment {
     browsingContextId: string;
     shellManager: IShellManager;
     targetDiv: HTMLElement;
+    useLocalCors?: string;
   }
 }

wasm/cockle-deploy/src/deployment.ts

@@ -1,4 +1,4 @@
-import { Shell } from '@jupyterlite/cockle'
+import { IShell, Shell } from '@jupyterlite/cockle'
 import { FitAddon } from '@xterm/addon-fit'
 import { Terminal } from '@xterm/xterm'
 import { IDeployment } from './defs'
@@ -22,13 +22,18 @@ export class Deployment {
 
     const { baseUrl, browsingContextId, shellManager } = options;
 
-    this._shell = new Shell({
+    const shellOptions: IShell.IOptions = {
       browsingContextId,
       baseUrl,
       wasmBaseUrl: baseUrl,
       shellManager,
       outputCallback: this.outputCallback.bind(this),
-    })
+    };
+    if (options.useLocalCors) {
+      shellOptions.environment = { GIT_CORS_PROXY: options.useLocalCors };
+    }
+
+    this._shell = new Shell(shellOptions);
   }
 
   async start(): Promise<void> {

wasm/cockle-deploy/src/index.ts

@@ -1,13 +1,28 @@
 import { ShellManager } from '@jupyterlite/cockle';
 import "./style/deployment.css"
+import { IDeployment } from './defs';
 import { Deployment } from "./deployment";
 
 document.addEventListener("DOMContentLoaded", async () => {
   const baseUrl = window.location.href;
   const shellManager = new ShellManager();
   const browsingContextId = await shellManager.installServiceWorker(baseUrl);
-
   const targetDiv: HTMLElement = document.getElementById('targetdiv')!;
-  const playground = new Deployment({ baseUrl, browsingContextId, shellManager, targetDiv });
+
+  const options: IDeployment.IOptions = {
+    baseUrl, browsingContextId, shellManager, targetDiv
+  }
+
+  // See if a local CORS proxy is available where we are expecting it by checking if it is there.
+  // This isn't good practice but is OK for local manual testing.
+  try {
+    const corsProxy = "http://localhost:8881/"
+    const response = await fetch(corsProxy);
+    if (response.ok && response.type == "cors") {
+      options.useLocalCors = corsProxy;
+    }
+  } catch (error) {}
+
+  const playground = new Deployment(options);
   await playground.start();
 })

wasm/cockle-deploy/tsconfig.json

@@ -13,7 +13,7 @@
     "noUnusedLocals": true,
     "preserveWatchOutput": true,
     "resolveJsonModule": true,
-    "outDir": "../serve/cockle",
+    "outDir": "../serve/dist/cockle",
     "rootDir": "src",
     "strict": true,
     "strictNullChecks": true,

wasm/lite-deploy/CMakeLists.txt

@@ -3,7 +3,7 @@ project(git2cpp-wasm-lite-deploy)
 
 include("../common.cmake")
 
-set(SERVE_DIR "../serve/lite")
+set(SERVE_DIR "../serve/dist/lite")
 
 add_custom_target(build-lite
     DEPENDS build-recipe cockle

wasm/serve/CMakeLists.txt

@@ -0,0 +1,8 @@
+cmake_minimum_required(VERSION 3.28)
+project(git2cpp-wasm)
+
+add_custom_target(build-serve COMMAND npm install)
+
+# Serve both cockle and JupyterLite deployments.
+add_custom_target(serve COMMAND npm run serve)
+add_custom_target(serve-with-cors COMMAND npm run serve-with-cors)

wasm/serve/package.json

@@ -0,0 +1,17 @@
+{
+    "name": "serve",
+    "version": "1.0.0",
+    "license": "BSD-3-Clause",
+    "private": true,
+    "scripts": {
+        "serve": "npm run serve:basic",
+        "serve-with-cors": "COCKLE_LOCAL_CORS=1 concurrently 'npm run serve:basic' 'npm run serve:cors'",
+        "serve:basic": "npx static-handler --cors --coop --coep --corp dist",
+        "serve:cors": "HOST=localhost PORT=8881 node node_modules/cors-anywhere/server.js "
+    },
+    "devDependencies": {
+        "concurrently": "^9.2.1",
+        "cors-anywhere": "^0.4.4",
+        "static-handler": "^0.5.3"
+    }
+}