☝🏼promote session shutdown events to errors for thebe sessions (#712)

* ☝🏼promote session shutdown events to errors for thebe sessions
* 📃added default args to clear session storage helpers
* 🦠 better path injection
* 👍 allow hypens in session names

.changeset/tender-sloths-battle.md

@@ -0,0 +1,5 @@
+---
+'thebe-react': patch
+---
+
+`ThebeSessionProvider` monitors status events for session/kernel shutdown messages and promotes this to an error if the corresponding session has shutdown.

.changeset/twenty-pigs-relax.md

@@ -0,0 +1,5 @@
+---
+'thebe-core': patch
+---
+
+Added default arguments to clear sesion storage utility functions

packages/core/src/server.ts

@@ -120,7 +120,7 @@ class ThebeServer implements ServerRuntime, ServerRestAPI {
     // https://jupyterlab.readthedocs.io/en/3.4.x/api/modules/services.session.html#isessionoptions
     const path = kernelOptions?.path ?? this.config.kernels.path;
     let name = 'thebe.ipynb';
-    const match = path.match(/\/*([a-zA-Z0-9]+.ipynb)$/);
+    const match = path.match(/\/*([a-zA-Z0-9-]+.ipynb)$/);
     if (match) {
       name = match[1];
     }

packages/core/src/sessions.ts

@@ -94,7 +94,7 @@ export async function getExistingServer(
  *
  * @param storagePrefix
  */
-export function clearAllSavedSessions(storagePrefix: string) {
+export function clearAllSavedSessions(storagePrefix: string = 'thebe-binder') {
   const keysToRemove: string[] = [];
   for (let i = 0; i < window.localStorage.length; i++) {
     const key = window.localStorage.key(i);
@@ -117,7 +117,7 @@ export function clearAllSavedSessions(storagePrefix: string) {
  * @param storagePrefix
  * @param url
  */
-export function clearSavedSession(storagePrefix: string, url: string) {
+export function clearSavedSession(storagePrefix: string = 'thebe-binder', url: string = '') {
   console.debug(`thebe:clearSavedSession - removing ${makeStorageKey(storagePrefix, url)}`);
   window.localStorage.removeItem(makeStorageKey(storagePrefix, url));
 }

packages/react/src/ThebeSessionProvider.tsx

@@ -2,6 +2,8 @@ import React, { useContext, useEffect, useState } from 'react';
 import type { ThebeSession } from 'thebe-core';
 import { useThebeServer } from './ThebeServerProvider';
 import { useRenderMimeRegistry } from './ThebeRenderMimeRegistryProvider';
+import { ThebeEventData } from 'thebe-core';
+import { useThebeLoader } from './ThebeLoaderProvider';
 
 interface ThebeSessionContextData {
   path?: string;
@@ -19,14 +21,15 @@ export const ThebeSessionContext = React.createContext<ThebeSessionContextData |
 
 export function ThebeSessionProvider({
   start = true,
-  path = '/thebe.ipynb',
+  path,
   shutdownOnUnmount = false,
   children,
 }: React.PropsWithChildren<{
   start?: boolean;
   path?: string;
   shutdownOnUnmount?: boolean;
 }>) {
+  const { core } = useThebeLoader();
   const { config, server, ready: serverReady } = useThebeServer();
   const rendermime = useRenderMimeRegistry();
 
@@ -42,10 +45,27 @@ export function ThebeSessionProvider({
     startSession();
   }, [ready, doStart, starting, server, serverReady]);
 
+  // register an event handler to monitor for session status changes
+  useEffect(() => {
+    if (!core || !config || !session) return;
+    const handler = (evt: string, data: ThebeEventData) => {
+      const subjects = [core.EventSubject.session, core.EventSubject.kernel];
+      if (
+        data.subject &&
+        subjects.includes(data.subject) &&
+        data.status === 'shutdown' &&
+        data.id === session.id
+      ) {
+        setError(`session ${session.path} - ${data.status} - ${data.message}`);
+      }
+    };
+    config.events.on(core.ThebeEventType.status, handler);
+  }, [core, config, session]);
+
   const startSession = () => {
     if (!rendermime) throw new Error('ThebeSessionProvider requires a RenderMimeRegistryProvider');
     setStarting(true);
-    server?.startNewSession(rendermime, { ...config?.kernels, path }).then(
+    server?.startNewSession(rendermime, { path }).then(
       (sesh: ThebeSession | null) => {
         setStarting(false);
         if (sesh == null) {