errors: add ConsumedResponse type + use for ResponseError

Signed-off-by: Patrik Oldsberg <poldsberg@gmail.com>

.changeset/sharp-numbers-taste.md

@@ -0,0 +1,7 @@
+---
+'@backstage/errors': minor
+---
+
+The `ResponseError.fromResponse` now accepts a more narrow response type, in order to avoid incompatibilities between different fetch implementations.
+
+The `response` property of `ResponseError` has also been narrowed to a new `ConsumedResponse` type that omits all the properties for consuming the body of the response. This is not considered a breaking change as it was always an error to try to consume the body of the response.

packages/errors/api-report.md

@@ -14,6 +14,17 @@ export class AuthenticationError extends CustomErrorBase {}
 // @public
 export class ConflictError extends CustomErrorBase {}
 
+// @public
+export type ConsumedResponse = {
+  readonly headers: Headers;
+  readonly ok: boolean;
+  readonly redirected: boolean;
+  readonly status: number;
+  readonly statusText: string;
+  readonly type: ResponseType;
+  readonly url: string;
+};
+
 // @public
 export class CustomErrorBase extends Error {
   constructor(message?: string, cause?: Error | unknown);
@@ -67,15 +78,21 @@ export class NotModifiedError extends CustomErrorBase {}
 
 // @public
 export function parseErrorResponseBody(
-  response: Response,
+  response: ConsumedResponse & {
+    text(): Promise<string>;
+  },
 ): Promise<ErrorResponseBody>;
 
 // @public
 export class ResponseError extends Error {
   readonly body: ErrorResponseBody;
   readonly cause: Error;
-  static fromResponse(response: Response): Promise<ResponseError>;
-  readonly response: Response;
+  static fromResponse(
+    response: ConsumedResponse & {
+      text(): Promise<string>;
+    },
+  ): Promise<ResponseError>;
+  readonly response: ConsumedResponse;
 }
 
 // @public

packages/errors/src/errors/ResponseError.ts

@@ -19,6 +19,7 @@ import {
   ErrorResponseBody,
   parseErrorResponseBody,
 } from '../serialization/response';
+import { ConsumedResponse } from './types';
 
 /**
  * An error thrown as the result of a failed server request.
@@ -34,7 +35,7 @@ export class ResponseError extends Error {
    * Note that the body of this response is always consumed. Its parsed form is
    * in the `body` field.
    */
-  readonly response: Response;
+  readonly response: ConsumedResponse;
 
   /**
    * The parsed JSON error body, as sent by the server.
@@ -59,7 +60,9 @@ export class ResponseError extends Error {
    * function consumes the body of the response, and assumes that it hasn't
    * been consumed before.
    */
-  static async fromResponse(response: Response): Promise<ResponseError> {
+  static async fromResponse(
+    response: ConsumedResponse & { text(): Promise<string> },
+  ): Promise<ResponseError> {
     const data = await parseErrorResponseBody(response);
 
     const status = data.response.statusCode || response.status;
@@ -77,7 +80,7 @@ export class ResponseError extends Error {
 
   private constructor(props: {
     message: string;
-    response: Response;
+    response: ConsumedResponse;
     data: ErrorResponseBody;
     cause: Error;
   }) {

packages/errors/src/errors/index.ts

@@ -27,3 +27,4 @@ export {
 } from './common';
 export { CustomErrorBase } from './CustomErrorBase';
 export { ResponseError } from './ResponseError';
+export type { ConsumedResponse } from './types';

packages/errors/src/errors/types.ts

@@ -0,0 +1,31 @@
+/*
+ * Copyright 2022 The Backstage Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+/**
+ * ConsumedResponse represents a Response that is known to have been consumed.
+ * The methods and properties used to read the body contents are therefore omitted.
+ *
+ * @public
+ */
+export type ConsumedResponse = {
+  readonly headers: Headers;
+  readonly ok: boolean;
+  readonly redirected: boolean;
+  readonly status: number;
+  readonly statusText: string;
+  readonly type: ResponseType;
+  readonly url: string;
+};

packages/errors/src/serialization/response.ts

@@ -14,6 +14,7 @@
  * limitations under the License.
  */
 
+import { ConsumedResponse } from '../errors/types';
 import { SerializedError } from './error';
 
 /**
@@ -53,7 +54,7 @@ export type ErrorResponseBody = {
  * @param response - The response of a failed request
  */
 export async function parseErrorResponseBody(
-  response: Response,
+  response: ConsumedResponse & { text(): Promise<string> },
 ): Promise<ErrorResponseBody> {
   try {
     const text = await response.text();