Add header property to Graph error object (#1133)

* headers prop in GraphError

* adding test

* changing the headers type

* remove commented code

Author: nikithauc

shims.d.ts

@@ -19,3 +19,5 @@ interface NodeStream {
     read(size?: number): any;
     on(event: string | symbol, listener: (...args: any[]) => void): this;
 }
+
+interface Headers{}

src/GraphError.ts

@@ -42,6 +42,8 @@ export class GraphError extends Error {
 	 */
 	public date: Date;
 
+    public headers?: Headers;
+
 	/**
 	 * @public
 	 * A member holding original error response by the graph service

src/GraphErrorHandler.ts

@@ -40,13 +40,14 @@ export class GraphErrorHandler {
 	 * @param {number} [statusCode] - The status code of the response
 	 * @returns The GraphError instance
 	 */
-	private static constructError(error: Error, statusCode?: number): GraphError {
+	private static constructError(error: Error, statusCode?: number, rawResponse?: Response): GraphError {
 		const gError = new GraphError(statusCode, "", error);
 		if (error.name !== undefined) {
 			gError.code = error.name;
 		}
 		gError.body = error.toString();
 		gError.date = new Date();
+		gError.headers = rawResponse?.headers;
 		return gError;
 	}
 
@@ -71,7 +72,7 @@ export class GraphErrorHandler {
 	 *      }
 	 *  }
 	 */
-	private static constructErrorFromResponse(graphError: GraphAPIErrorResponse, statusCode: number): GraphError {
+	private static constructErrorFromResponse(graphError: GraphAPIErrorResponse, statusCode: number, rawResponse?: Response): GraphError {
 		const error = graphError.error;
 		const gError = new GraphError(statusCode, error.message);
 		gError.code = error.code;
@@ -81,6 +82,7 @@ export class GraphErrorHandler {
 		}
 
 		gError.body = JSON.stringify(error);
+		gError.headers = rawResponse?.headers;
 
 		return gError;
 	}
@@ -96,12 +98,12 @@ export class GraphErrorHandler {
 	 * @param {GraphRequestCallback} [callback] - The graph request callback function
 	 * @returns A promise that resolves to GraphError instance
 	 */
-	public static async getError(error: any = null, statusCode = -1, callback?: GraphRequestCallback): Promise<GraphError> {
+	public static async getError(error: any = null, statusCode = -1, callback?: GraphRequestCallback, rawResponse?: Response): Promise<GraphError> {
 		let gError: GraphError;
 		if (error && error.error) {
-			gError = GraphErrorHandler.constructErrorFromResponse(error, statusCode);
+			gError = GraphErrorHandler.constructErrorFromResponse(error, statusCode, rawResponse);
 		} else if (error instanceof Error) {
-			gError = GraphErrorHandler.constructError(error, statusCode);
+			gError = GraphErrorHandler.constructError(error, statusCode, rawResponse);
 		} else {
 			gError = new GraphError(statusCode);
 			gError.body = error; // if a custom error is passed which is not instance of Error object or a graph API response

src/GraphRequest.ts

@@ -388,7 +388,7 @@ export class GraphRequest {
 			if (rawResponse) {
 				statusCode = rawResponse.status;
 			}
-			const gError: GraphError = await GraphErrorHandler.getError(error, statusCode, callback);
+			const gError: GraphError = await GraphErrorHandler.getError(error, statusCode, callback, rawResponse);
 			throw gError;
 		}
 	}

test/common/core/GraphErrorHandler.ts

@@ -108,5 +108,24 @@ describe("GraphErrorHandler.ts", () => {
 			assert.equal(gError.body, null);
 			assert.equal(gError.requestId, null);
 		});
+
+		it("Should get header from response", async () => {
+			const headers = { keyTest: "valueTest" };
+			const errorResponse = {
+				error: {
+					code: "500",
+					message: "Internal Server Error",
+					innerError: {
+						"request-id": "some random id",
+					},
+				},
+			};
+			const rawResponse = new Response(undefined, {
+				headers: new Headers(headers),
+			});
+			const gError = await GraphErrorHandler.getError(errorResponse, 500, undefined, rawResponse);
+			assert.isDefined(gError.headers);
+			assert.equal(gError.headers?.get("keyTest"), headers.keyTest);
+		});
 	});
 });