bug(EmailReadImap Node): Improve error handling (#2991)

* Fix: EmailReadImap unhandled promise rejection

Related to #2091 (but only partially)

See #2091 (comment)

* Send errors from email read imap to logger

Co-authored-by: Manuel [tennox] <2084639+tennox@users.noreply.github.com>

packages/nodes-base/nodes/EmailReadImap/EmailReadImap.node.ts

@@ -7,6 +7,7 @@ import {
 	INodeType,
 	INodeTypeDescription,
 	ITriggerResponse,
+	LoggerProxy,
 	NodeOperationError,
 } from 'n8n-workflow';
 
@@ -377,6 +378,18 @@ export class EmailReadImap implements INodeType {
 		};
 
 		const establishConnection = (): Promise<ImapSimple> => {
+
+			let searchCriteria = [
+				'UNSEEN',
+			] as Array<string | string[]>;
+			if (options.customEmailConfig !== undefined) {
+				try {
+					searchCriteria = JSON.parse(options.customEmailConfig as string);
+				} catch (error) {
+					throw new NodeOperationError(this.getNode(), `Custom email config is not valid JSON.`);
+				}
+			}
+
 			const config: ImapSimpleOptions = {
 				imap: {
 					user: credentials.user as string,
@@ -388,16 +401,6 @@ export class EmailReadImap implements INodeType {
 				},
 				onmail: async () => {
 					if (connection) {
-						let searchCriteria = [
-							'UNSEEN',
-						] as Array<string | string[]>;
-						if (options.customEmailConfig !== undefined) {
-							try {
-								searchCriteria = JSON.parse(options.customEmailConfig as string);
-							} catch (error) {
-								throw new NodeOperationError(this.getNode(), `Custom email config is not valid JSON.`);
-							}
-						}
 						if (staticData.lastMessageUid !== undefined) {
 							searchCriteria.push(['UID', `${staticData.lastMessageUid as number}:*`]);
 							/**
@@ -415,10 +418,14 @@ export class EmailReadImap implements INodeType {
 							Logger.debug('Querying for new messages on node "EmailReadImap"', {searchCriteria});
 						}
 
-						const returnData = await getNewEmails(connection, searchCriteria);
-
-						if (returnData.length) {
-							this.emit([returnData]);
+						try {
+							const returnData = await getNewEmails(connection, searchCriteria);
+							if (returnData.length) {
+								this.emit([returnData]);
+							}
+						} catch (error) {
+							Logger.error('Email Read Imap node encountered an error fetching new emails', { error });
+							throw error;
 						}
 					}
 				},