[Ingest Manager] Improve server-side error handling (#67278)

* Use IngestManagerError instead of Boom errors.

* Extend Error and simplify.

* Add registry url to error messages.

Co-authored-by: Elastic Machine <elasticmachine@users.noreply.github.com>

x-pack/plugins/ingest_manager/server/errors.ts

@@ -0,0 +1,29 @@
+/*
+ * Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
+ * or more contributor license agreements. Licensed under the Elastic License;
+ * you may not use this file except in compliance with the Elastic License.
+ */
+
+export class IngestManagerError extends Error {
+  public type: IngestManagerErrorType;
+  public message: string;
+
+  constructor(type: IngestManagerErrorType, message: string) {
+    super(message);
+    this.type = type;
+    this.message = message;
+  }
+}
+
+export const getHTTPResponseCode = (error: IngestManagerError): number => {
+  switch (error.type) {
+    case IngestManagerErrorType.RegistryError:
+      return 502; // Bad Gateway
+    default:
+      return 400; // Bad Request
+  }
+};
+
+export enum IngestManagerErrorType {
+  RegistryError,
+}

x-pack/plugins/ingest_manager/server/routes/setup/handlers.ts

@@ -9,6 +9,7 @@ import { outputService, appContextService } from '../../services';
 import { GetFleetStatusResponse } from '../../../common';
 import { setupIngestManager, setupFleet } from '../../services/setup';
 import { PostFleetSetupRequestSchema } from '../../types';
+import { IngestManagerError, getHTTPResponseCode } from '../../errors';
 
 export const getFleetStatusHandler: RequestHandler = async (context, request, response) => {
   const soClient = context.core.savedObjects.client;
@@ -81,6 +82,13 @@ export const ingestManagerSetupHandler: RequestHandler = async (context, request
       body: { isInitialized: true },
     });
   } catch (e) {
+    if (e instanceof IngestManagerError) {
+      logger.error(e.message);
+      return response.customError({
+        statusCode: getHTTPResponseCode(e),
+        body: { message: e.message },
+      });
+    }
     if (e.isBoom) {
       logger.error(e.output.payload.message);
       return response.customError({

x-pack/plugins/ingest_manager/server/services/epm/registry/requests.ts

@@ -4,9 +4,9 @@
  * you may not use this file except in compliance with the Elastic License.
  */
 
-import Boom from 'boom';
 import fetch, { Response } from 'node-fetch';
 import { streamToString } from './streams';
+import { IngestManagerError, IngestManagerErrorType } from '../../../errors';
 
 export async function getResponse(url: string): Promise<Response> {
   try {
@@ -14,10 +14,16 @@ export async function getResponse(url: string): Promise<Response> {
     if (response.ok) {
       return response;
     } else {
-      throw new Boom(response.statusText, { statusCode: response.status });
+      throw new IngestManagerError(
+        IngestManagerErrorType.RegistryError,
+        `Error connecting to package registry at ${url}: ${response.statusText}`
+      );
     }
   } catch (e) {
-    throw new Boom(`Error connecting to package registry: ${e.message}`, { statusCode: 502 });
+    throw new IngestManagerError(
+      IngestManagerErrorType.RegistryError,
+      `Error connecting to package registry at ${url}: ${e.message}`
+    );
   }
 }