Add SageMaker-UI env endpoint patch

**Description**

* Adding `/api/env` endpoint for the SageMaker Unified Studio user case that fetched the `/opt/ml/metadata/resource-metadata.json` file if present else throw server exception indicating no such file.

**Motivation**

* SMUS extensions would require this env metadata file.

**Testing Done**

* Build CE package and ran locally. Tested building the local image using BYOI

**Backwards Compatibility Criteria (if any)**

* N/A

Author: guntamb

patched-vscode/src/vs/server/node/webClientServer.ts

@@ -3,7 +3,7 @@
  *  Licensed under the MIT License. See License.txt in the project root for license information.
  *--------------------------------------------------------------------------------------------*/
 
-import { createReadStream } from 'fs';
+import { createReadStream, existsSync, writeFileSync } from 'fs';
 import {readFile } from 'fs/promises';
 import { Promises } from 'vs/base/node/pfs';
 import * as path from 'path';
@@ -102,6 +102,7 @@ export class WebClientServer {
 	private readonly _callbackRoute: string;
 	private readonly _webExtensionRoute: string;
 	private readonly _idleRoute: string;
+	private readonly _envMetadata: string;
 
 	constructor(
 		private readonly _connectionToken: ServerConnectionToken,
@@ -118,6 +119,7 @@ export class WebClientServer {
 		this._callbackRoute = `${serverRootPath}/callback`;
 		this._webExtensionRoute = `${serverRootPath}/web-extension-resource`;
 		this._idleRoute = '/api/idle';
+		this._envMetadata = '/api/env';
 	}
 
 	/**
@@ -146,6 +148,9 @@ export class WebClientServer {
 				// extension resource support
 				return this._handleWebExtensionResource(req, res, parsedUrl);
 			}
+			if (pathname === this._envMetadata) {
+				return this._handleEnvMetadata(req, res);
+			}
 
 			return serveError(req, res, 404, 'Not found.');
 		} catch (error) {
@@ -459,12 +464,20 @@ export class WebClientServer {
 	}
 
 	/**
- 	 * Handles API requests to retrieve the last activity timestamp.
-   */
+	 * Handles API requests to retrieve the last activity timestamp.
+	 */
 	private async _handleIdle(req: http.IncomingMessage, res: http.ServerResponse): Promise<void> {
 		try {
 			const tmpDirectory = '/tmp/'
 			const idleFilePath = path.join(tmpDirectory, '.sagemaker-last-active-timestamp');
+
+			// If idle shutdown file does not exist, this indicates the app UI may never been opened
+			// Create the initial metadata file
+			if (!existsSync(idleFilePath)) {
+				const timestamp = new Date().toISOString();
+				writeFileSync(idleFilePath, timestamp);
+			}
+
 			const data = await readFile(idleFilePath, 'utf8');
 
 			res.statusCode = 200;
@@ -474,6 +487,26 @@ export class WebClientServer {
 			serveError(req, res, 500, error.message)
 		}
 	}
+
+	/**
+	 * Handles API requests to retrieve the /opt/ml/metadata/resource-metadata.json file.
+	 */
+	private async _handleEnvMetadata(req: http.IncomingMessage, res: http.ServerResponse): Promise<void> {
+		try {
+			const envMetadataDirectory = '/opt/ml/metadata/';
+			const envMetadataFilePath = path.join(envMetadataDirectory, 'resource-metadata.json');
+			if (existsSync(envMetadataFilePath)) {
+				const envMetadata = await readFile(envMetadataFilePath, 'utf8');
+				res.statusCode = 200;
+				res.setHeader('Content-Type', 'application/json');
+				res.end(envMetadata);
+			} else {
+				serveError(req, res, 500, 'No metadata file at ' + envMetadataFilePath);
+			}
+		} catch (error) {
+			serveError(req, res, 500, error.message);
+		}
+	}
 }
 
 /**

patches/sagemaker-ui-env.patch

@@ -0,0 +1,57 @@
+Index: sagemaker-code-editor/vscode/src/vs/server/node/webClientServer.ts
+===================================================================
+--- sagemaker-code-editor.orig/vscode/src/vs/server/node/webClientServer.ts
++++ sagemaker-code-editor/vscode/src/vs/server/node/webClientServer.ts
+@@ -102,6 +102,7 @@ export class WebClientServer {
+ 	private readonly _callbackRoute: string;
+ 	private readonly _webExtensionRoute: string;
+ 	private readonly _idleRoute: string;
++	private readonly _envMetadata: string;
+ 
+ 	constructor(
+ 		private readonly _connectionToken: ServerConnectionToken,
+@@ -118,6 +119,7 @@ export class WebClientServer {
+ 		this._callbackRoute = `${serverRootPath}/callback`;
+ 		this._webExtensionRoute = `${serverRootPath}/web-extension-resource`;
+ 		this._idleRoute = '/api/idle';
++		this._envMetadata = '/api/env';
+ 	}
+ 
+ 	/**
+@@ -146,6 +148,9 @@ export class WebClientServer {
+ 				// extension resource support
+ 				return this._handleWebExtensionResource(req, res, parsedUrl);
+ 			}
++			if (pathname === this._envMetadata) {
++				return this._handleEnvMetadata(req, res);
++			}
+ 
+ 			return serveError(req, res, 404, 'Not found.');
+ 		} catch (error) {
+@@ -482,6 +487,26 @@ export class WebClientServer {
+ 			serveError(req, res, 500, error.message)
+ 		}
+ 	}
++
++	/**
++	 * Handles API requests to retrieve the /opt/ml/metadata/resource-metadata.json file.
++	 */
++	private async _handleEnvMetadata(req: http.IncomingMessage, res: http.ServerResponse): Promise<void> {
++		try {
++			const envMetadataDirectory = '/opt/ml/metadata/';
++			const envMetadataFilePath = path.join(envMetadataDirectory, 'resource-metadata.json');
++			if (existsSync(envMetadataFilePath)) {
++				const envMetadata = await readFile(envMetadataFilePath, 'utf8');
++				res.statusCode = 200;
++				res.setHeader('Content-Type', 'application/json');
++				res.end(envMetadata);
++			} else {
++				serveError(req, res, 500, 'No metadata file at ' + envMetadataFilePath);
++			}
++		} catch (error) {
++			serveError(req, res, 500, error.message);
++		}
++	}
+ }
+ 
+ /**

patches/series

@@ -11,3 +11,4 @@ sagemaker-idle-extension.patch
 terminal-crash-mitigation.patch
 sagemaker-open-notebook-extension.patch
 security.diff
+sagemaker-ui-env.patch