Passing the link of empack_env_meta.json file

jupyterlite_xeus/add_on.py

@@ -1,4 +1,5 @@
 """a JupyterLite addon for creating the env for xeus kernels"""
+
 import json
 import os
 from pathlib import Path
@@ -18,7 +19,7 @@
     SHARE_LABEXTENSIONS,
     UTF8,
 )
-from traitlets import Bool, List, Unicode
+from traitlets import Bool, Callable, List, Unicode
 
 from .create_conda_env import (
     create_conda_env_from_env_file,
@@ -102,6 +103,13 @@ class XeusAddon(FederatedExtensionAddon):
         description="A comma-separated list of mount points, in the form <host_path>:<mount_path> to mount in the wasm prefix",
     )
 
+    package_url_factory = Callable(
+        None,
+        allow_none=True,
+        config=True,
+        description="Factory to generate package download URL from package metadata. This is used to load python packages from external host",
+    )
+
     def __init__(self, *args, **kwargs):
         super().__init__(*args, **kwargs)
         self.xeus_output_dir = Path(self.manager.output_dir) / "xeus"
@@ -285,6 +293,9 @@ def pack_prefix(self, kernel_dir):
         else:
             pack_kwargs["file_filters"] = pkg_file_filter_from_yaml(DEFAULT_CONFIG_PATH)
 
+        if self.package_url_factory is not None:
+            pack_kwargs["package_url_factory"] = self.package_url_factory
+
         pack_env(
             env_prefix=self.prefix,
             relocate_prefix="/",
@@ -342,7 +353,8 @@ def pack_prefix(self, kernel_dir):
         # Pack JupyterLite content if enabled
         # If we only build a voici output, mount jupyterlite content into the kernel by default
         if self.mount_jupyterlite_content or (
-            list(self.manager.apps) == ["voici"] and self.mount_jupyterlite_content is None
+            list(self.manager.apps) == ["voici"]
+            and self.mount_jupyterlite_content is None
         ):
             contents_dir = self.manager.output_dir / "files"
 

src/index.ts

@@ -12,6 +12,7 @@ import { IBroadcastChannelWrapper } from '@jupyterlite/contents';
 import { IKernel, IKernelSpecs } from '@jupyterlite/kernel';
 
 import { WebWorkerKernel } from './web_worker_kernel';
+import { IEmpackEnvMetaFile } from './tokens';
 
 function getJson(url: string) {
   const json_url = URLExt.join(PageConfig.getBaseUrl(), url);
@@ -29,59 +30,89 @@ try {
   throw err;
 }
 
-const plugins = kernel_list.map((kernel): JupyterLiteServerPlugin<void> => {
-  return {
-    id: `@jupyterlite/xeus-${kernel}:register`,
-    autoStart: true,
-    requires: [IKernelSpecs],
-    optional: [IServiceWorkerManager, IBroadcastChannelWrapper],
-    activate: (
-      app: JupyterLiteServer,
-      kernelspecs: IKernelSpecs,
-      serviceWorker?: IServiceWorkerManager,
-      broadcastChannel?: IBroadcastChannelWrapper
-    ) => {
-      // Fetch kernel spec
-      const kernelspec = getJson('xeus/kernels/' + kernel + '/kernel.json');
-      kernelspec.name = kernel;
-      kernelspec.dir = kernel;
-      for (const [key, value] of Object.entries(kernelspec.resources)) {
-        kernelspec.resources[key] = URLExt.join(
-          PageConfig.getBaseUrl(),
-          value as string
-        );
-      }
-
-      const contentsManager = app.serviceManager.contents;
-
-      kernelspecs.register({
-        spec: kernelspec,
-        create: async (options: IKernel.IOptions): Promise<IKernel> => {
-          const mountDrive = !!(
-            (serviceWorker?.enabled && broadcastChannel?.enabled) ||
-            crossOriginIsolated
+const plugins = kernel_list.map(
+  (kernel): JupyterLiteServerPlugin<void | IEmpackEnvMetaFile> => {
+    return {
+      id: `@jupyterlite/xeus-${kernel}:register`,
+      autoStart: true,
+      requires: [IKernelSpecs],
+      optional: [
+        IServiceWorkerManager,
+        IBroadcastChannelWrapper,
+        IEmpackEnvMetaFile
+      ],
+      activate: (
+        app: JupyterLiteServer,
+        kernelspecs: IKernelSpecs,
+        serviceWorker?: IServiceWorkerManager,
+        broadcastChannel?: IBroadcastChannelWrapper,
+        empackEnvMetaFile?: IEmpackEnvMetaFile
+      ) => {
+        // Fetch kernel spec
+        const kernelspec = getJson('xeus/kernels/' + kernel + '/kernel.json');
+        kernelspec.name = kernel;
+        kernelspec.dir = kernel;
+        for (const [key, value] of Object.entries(kernelspec.resources)) {
+          kernelspec.resources[key] = URLExt.join(
+            PageConfig.getBaseUrl(),
+            value as string
           );
+        }
 
-          if (mountDrive) {
-            console.info(
-              `${kernelspec.name} contents will be synced with Jupyter Contents`
-            );
-          } else {
-            console.warn(
-              `${kernelspec.name} contents will NOT be synced with Jupyter Contents`
+        const contentsManager = app.serviceManager.contents;
+        kernelspecs.register({
+          spec: kernelspec,
+          create: async (options: IKernel.IOptions): Promise<IKernel> => {
+            const mountDrive = !!(
+              (serviceWorker?.enabled && broadcastChannel?.enabled) ||
+              crossOriginIsolated
             );
+
+            if (mountDrive) {
+              console.info(
+                `${kernelspec.name} contents will be synced with Jupyter Contents`
+              );
+            } else {
+              console.warn(
+                `${kernelspec.name} contents will NOT be synced with Jupyter Contents`
+              );
+            }
+            const link = empackEnvMetaFile
+              ? await empackEnvMetaFile.getLink(kernelspec)
+              : '';
+
+            return new WebWorkerKernel({
+              ...options,
+              contentsManager,
+              mountDrive,
+              kernelSpec: kernelspec,
+              empackEnvMetaLink: link
+            });
           }
+        });
+      }
+    };
+  }
+);
 
-          return new WebWorkerKernel({
-            ...options,
-            contentsManager,
-            mountDrive,
-            kernelSpec: kernelspec
-          });
-        }
-      });
-    }
-  };
-});
+const empackEnvMetaPlugin: JupyterLiteServerPlugin<IEmpackEnvMetaFile> = {
+  id: '@jupyterlite/xeus:empack-env-meta',
+  autoStart: true,
+  provides: IEmpackEnvMetaFile,
+  activate: (): IEmpackEnvMetaFile => {
+    return {
+      getLink: async (kernelspec: Record<string, any>) => {
+        const kernelName = kernelspec.name;
+        const kernel_root_url = URLExt.join(
+          PageConfig.getBaseUrl(),
+          `xeus/kernels/${kernelName}`
+        );
+        return `${kernel_root_url}`;
+      }
+    };
+  }
+};
+
+plugins.push(empackEnvMetaPlugin);
 
 export default plugins;

src/tokens.ts

@@ -12,6 +12,7 @@ import {
 } from '@jupyterlite/contents';
 
 import { IWorkerKernel } from '@jupyterlite/kernel';
+import { Token } from '@lumino/coreutils';
 
 /**
  * An interface for Xeus workers.
@@ -85,5 +86,17 @@ export namespace IXeusWorkerKernel {
     baseUrl: string;
     kernelSpec: any;
     mountDrive: boolean;
+    empackEnvMetaLink?: string;
   }
 }
+
+export interface IEmpackEnvMetaFile {
+  /**
+   * Get empack_env_meta link.
+   */
+  getLink: (kernelspec: Record<string, any>) => Promise<string>;
+}
+
+export const IEmpackEnvMetaFile = new Token<IEmpackEnvMetaFile>(
+  '@jupyterlite/xeus:IEmpackEnvMetaFile'
+);

src/web_worker_kernel.ts

@@ -29,17 +29,24 @@ export class WebWorkerKernel implements IKernel {
    * @param options The instantiation options for a new WebWorkerKernel
    */
   constructor(options: WebWorkerKernel.IOptions) {
-    const { id, name, sendMessage, location, kernelSpec, contentsManager } =
-      options;
+    const {
+      id,
+      name,
+      sendMessage,
+      location,
+      kernelSpec,
+      contentsManager,
+      empackEnvMetaLink
+    } = options;
     this._id = id;
     this._name = name;
     this._location = location;
     this._kernelSpec = kernelSpec;
     this._contentsManager = contentsManager;
     this._sendMessage = sendMessage;
+    this._empackEnvMetaLink = empackEnvMetaLink;
     this._worker = this.initWorker(options);
     this._remoteKernel = this.initRemote(options);
-
     this.initFileSystem(options);
   }
 
@@ -99,11 +106,13 @@ export class WebWorkerKernel implements IKernel {
       };
       remote = wrap(this._worker) as Remote<IXeusWorkerKernel>;
     }
+
     remote
       .initialize({
         kernelSpec: this._kernelSpec,
         baseUrl: PageConfig.getBaseUrl(),
-        mountDrive: options.mountDrive
+        mountDrive: options.mountDrive,
+        empackEnvMetaLink: this._empackEnvMetaLink
       })
       .then(this._ready.resolve.bind(this._ready));
 
@@ -290,6 +299,7 @@ export class WebWorkerKernel implements IKernel {
     | undefined = undefined;
   private _parent: KernelMessage.IMessage | undefined = undefined;
   private _ready = new PromiseDelegate<void>();
+  private _empackEnvMetaLink: string | undefined;
 }
 
 /**
@@ -303,5 +313,6 @@ export namespace WebWorkerKernel {
     contentsManager: Contents.IManager;
     mountDrive: boolean;
     kernelSpec: any;
+    empackEnvMetaLink?: string | undefined;
   }
 }

src/worker.ts

@@ -103,7 +103,7 @@ export class XeusRemoteKernel {
   }
 
   async initialize(options: IXeusWorkerKernel.IOptions): Promise<void> {
-    const { baseUrl, kernelSpec } = options;
+    const { baseUrl, kernelSpec, empackEnvMetaLink } = options;
     // location of the kernel binary on the server
     const binary_js = URLExt.join(baseUrl, kernelSpec.argv[0]);
     const binary_wasm = binary_js.replace('.js', '.wasm');
@@ -125,10 +125,9 @@ export class XeusRemoteKernel {
       // This function is usually implemented in the pre/post.js
       // in the emscripten build of that kernel
       if (globalThis.Module['async_init'] !== undefined) {
-        const kernel_root_url = URLExt.join(
-          baseUrl,
-          `xeus/kernels/${kernelSpec.dir}`
-        );
+        const kernel_root_url = empackEnvMetaLink
+          ? empackEnvMetaLink
+          : URLExt.join(baseUrl, `xeus/kernels/${kernelSpec.dir}`);
         const pkg_root_url = URLExt.join(baseUrl, 'xeus/kernel_packages');
         const verbose = true;
         await globalThis.Module['async_init'](