feat: sourcegraphURL for extensions, passing through init data

Author: sqs

src/extension/extensionHost.ts

@@ -30,24 +30,37 @@ const consoleLogger: Logger = {
     },
 }
 
+/**
+ * Required information when initializing an extension host.
+ */
+export interface InitData {
+    /** The URL to the JavaScript source file (that exports an `activate` function) for the extension. */
+    bundleURL: string
+
+    /** @see {@link module:sourcegraph.internal.sourcegraphURL} */
+    sourcegraphURL: string
+}
+
 /**
  * Creates the Sourcegraph extension host and the extension API handle (which extensions access with `import
  * sourcegraph from 'sourcegraph'`).
  *
+ * @param initData The information to initialize this extension host.
  * @param transports The message reader and writer to use for communication with the client. Defaults to
  *                   communicating using self.postMessage and MessageEvents with the parent (assuming that it is
  *                   called in a Web Worker).
  * @return The extension API.
  */
 export function createExtensionHost(
+    initData: InitData,
     transports: MessageTransports = createWebWorkerMessageTransports()
 ): typeof sourcegraph {
     const connection = createConnection(transports, consoleLogger)
     connection.listen()
-    return createExtensionHandle(connection)
+    return createExtensionHandle(initData, connection)
 }
 
-function createExtensionHandle(connection: Connection): typeof sourcegraph {
+function createExtensionHandle(initData: InitData, connection: Connection): typeof sourcegraph {
     const subscription = new Subscription()
     subscription.add(connection)
 
@@ -127,6 +140,7 @@ function createExtensionHandle(connection: Connection): typeof sourcegraph {
         internal: {
             sync,
             updateContext: updates => context.updateContext(updates),
+            sourcegraphURL: new URI(initData.sourcegraphURL),
         },
     }
 }

src/extension/workerMain.ts

@@ -1,5 +1,5 @@
 import { tryCatchPromise } from '../util'
-import { createExtensionHost } from './extensionHost'
+import { createExtensionHost, InitData } from './extensionHost'
 
 interface MessageEvent {
     data: any
@@ -23,8 +23,8 @@ interface DedicatedWorkerGlobalScope {
 /**
  * The entrypoint for Web Workers that are spawned to run an extension.
  *
- * To initialize the worker, the parent sends it a message whose data is a URL of the extension's JavaScript
- * bundle.
+ * To initialize the worker, the parent sends it a message whose data is an object conforming to the
+ * {@link InitData} interface. Among other things, this contains the URL of the extension's JavaScript bundle.
  *
  * @param self The worker's `self` global scope.
  */
@@ -40,13 +40,13 @@ export function extensionHostWorkerMain(self: DedicatedWorkerGlobalScope): void
             self.close()
         }
 
-        const bundleURL: string = ev.data
-        if (typeof bundleURL !== 'string' || !bundleURL.startsWith('blob:')) {
-            console.error(`Invalid extension bundle URL: ${bundleURL}`)
+        const initData: InitData = ev.data
+        if (typeof initData.bundleURL !== 'string' || !initData.bundleURL.startsWith('blob:')) {
+            console.error(`Invalid extension bundle URL: ${initData.bundleURL}`)
             self.close()
         }
 
-        const api = createExtensionHost()
+        const api = createExtensionHost(initData)
         // Make `import 'sourcegraph'` or `require('sourcegraph')` return the extension host's
         // implementation of the `sourcegraph` module.
         ;(self as any).require = (modulePath: string): any => {
@@ -60,7 +60,7 @@ export function extensionHostWorkerMain(self: DedicatedWorkerGlobalScope): void
         // `module` property.
         ;(self as any).exports = {}
         ;(self as any).module = {}
-        self.importScripts(bundleURL)
+        self.importScripts(initData.bundleURL)
         const extensionExports = (self as any).module.exports
         delete (self as any).module
 

src/integration-test/helpers.test.ts

@@ -40,7 +40,10 @@ export async function integrationTestContext(): Promise<
     // Ack all configuration updates.
     clientController.configurationUpdates.subscribe(({ resolve }) => resolve(Promise.resolve()))
 
-    const extensionHost = createExtensionHost(serverTransports)
+    const extensionHost = createExtensionHost(
+        { bundleURL: '', sourcegraphURL: 'https://example.com' },
+        serverTransports
+    )
 
     // Wait for client to be ready.
     await clientController.clientEntries

src/sourcegraph.d.ts

@@ -829,6 +829,14 @@ declare module 'sourcegraph' {
          * @param updates The updates to apply to the context. If a context property's value is null, it is deleted from the context.
          */
         export function updateContext(updates: ContextValues): void
+
+        /**
+         * The URL to the Sourcegraph site that the user's session is associated with. This refers to
+         * Sourcegraph.com (`https://sourcegraph.com`) by default, or a self-hosted instance of Sourcegraph.
+         *
+         * @example `https://sourcegraph.com`
+         */
+        export const sourcegraphURL: URI
     }
 
     /**