refactor(core): Convert dynamic node-parameter routes to a decorated controller (no-changelog) (#7284)

1. Reduce a lot of code duplication
2. Move more endpoints out of `Server.ts`
3. Move all query-param parsing and validation into a middleware to make
the route handlers simpler.

packages/cli/src/controllers/dynamicNodeParameters.controller.ts

@@ -0,0 +1,120 @@
+import { Service } from 'typedi';
+import type { RequestHandler } from 'express';
+import { NextFunction, Response } from 'express';
+import type {
+	INodeListSearchResult,
+	INodePropertyOptions,
+	ResourceMapperFields,
+} from 'n8n-workflow';
+import { jsonParse } from 'n8n-workflow';
+
+import { Authorized, Get, Middleware, RestController } from '@/decorators';
+import { getBase } from '@/WorkflowExecuteAdditionalData';
+import { DynamicNodeParametersService } from '@/services/dynamicNodeParameters.service';
+import { DynamicNodeParametersRequest } from '@/requests';
+import { BadRequestError } from '@/ResponseHelper';
+
+const assertMethodName: RequestHandler = (req, res, next) => {
+	const { methodName } = req.query as DynamicNodeParametersRequest.BaseRequest['query'];
+	if (!methodName) {
+		throw new BadRequestError('Parameter methodName is required.');
+	}
+	next();
+};
+
+@Service()
+@Authorized()
+@RestController('/dynamic-node-parameters')
+export class DynamicNodeParametersController {
+	constructor(private readonly service: DynamicNodeParametersService) {}
+
+	@Middleware()
+	parseQueryParams(
+		req: DynamicNodeParametersRequest.BaseRequest,
+		res: Response,
+		next: NextFunction,
+	) {
+		const { credentials, currentNodeParameters, nodeTypeAndVersion } = req.query;
+		if (!nodeTypeAndVersion) {
+			throw new BadRequestError('Parameter nodeTypeAndVersion is required.');
+		}
+		if (!currentNodeParameters) {
+			throw new BadRequestError('Parameter currentNodeParameters is required.');
+		}
+
+		req.params = {
+			nodeTypeAndVersion: jsonParse(nodeTypeAndVersion),
+			currentNodeParameters: jsonParse(currentNodeParameters),
+			credentials: credentials ? jsonParse(credentials) : undefined,
+		};
+
+		next();
+	}
+
+	/** Returns parameter values which normally get loaded from an external API or get generated dynamically */
+	@Get('/options')
+	async getOptions(req: DynamicNodeParametersRequest.Options): Promise<INodePropertyOptions[]> {
+		const { path, methodName, loadOptions } = req.query;
+		const { credentials, currentNodeParameters, nodeTypeAndVersion } = req.params;
+		const additionalData = await getBase(req.user.id, currentNodeParameters);
+
+		if (methodName) {
+			return this.service.getOptionsViaMethodName(
+				methodName,
+				path,
+				additionalData,
+				nodeTypeAndVersion,
+				currentNodeParameters,
+				credentials,
+			);
+		}
+
+		if (loadOptions) {
+			return this.service.getOptionsViaLoadOptions(
+				jsonParse(loadOptions),
+				additionalData,
+				nodeTypeAndVersion,
+				currentNodeParameters,
+				credentials,
+			);
+		}
+
+		return [];
+	}
+
+	@Get('/resource-locator-results', { middlewares: [assertMethodName] })
+	async getResourceLocatorResults(
+		req: DynamicNodeParametersRequest.ResourceLocatorResults,
+	): Promise<INodeListSearchResult | undefined> {
+		const { path, methodName, filter, paginationToken } = req.query;
+		const { credentials, currentNodeParameters, nodeTypeAndVersion } = req.params;
+		const additionalData = await getBase(req.user.id, currentNodeParameters);
+		return this.service.getResourceLocatorResults(
+			methodName,
+			path,
+			additionalData,
+			nodeTypeAndVersion,
+			currentNodeParameters,
+			credentials,
+			filter,
+			paginationToken,
+		);
+	}
+
+	@Get('/resource-mapper-fields', { middlewares: [assertMethodName] })
+	async getResourceMappingFields(
+		req: DynamicNodeParametersRequest.ResourceMapperFields,
+	): Promise<ResourceMapperFields | undefined> {
+		const { path, methodName } = req.query;
+		const { credentials, currentNodeParameters, nodeTypeAndVersion } = req.params;
+		const additionalData = await getBase(req.user.id, currentNodeParameters);
+		return this.service.getResourceMappingFields(
+			methodName,
+			path,
+			additionalData,
+			nodeTypeAndVersion,
+			currentNodeParameters,
+			credentials,
+		);
+	}
+}