Improvements

Author: robertpitt

examples/simple/index.ts

@@ -6,9 +6,7 @@ import { createRouter } from '../../src/index.ts';
 import {
   createSpotlightElementsHtml,
   formatCalculateResponseXML,
-  formatCalculateErrorXML,
   formatCalculateResponseHTML,
-  formatCalculateErrorHTML,
 } from './utils.ts';
 import { IRequest } from 'itty-router';
 
@@ -35,29 +33,6 @@ const router = createRouter<typeof contract, IRequest, [ExampleContext]>({
       // Headers are normalized to lowercase in types and runtime, regardless of how they're defined in the schema
       const contentType = request.validatedHeaders.get('content-type');
 
-      if (result > 100) {
-        const errorMessage = 'Invalid request';
-        if (contentType === 'text/html') {
-          return request.respond({
-            status: 400,
-            contentType: 'text/html',
-            body: formatCalculateErrorHTML(errorMessage),
-          });
-        }
-        if (contentType === 'application/xml') {
-          return request.respond({
-            status: 400,
-            contentType: 'application/xml',
-            body: formatCalculateErrorXML(errorMessage),
-          });
-        }
-        return request.respond({
-          status: 400,
-          contentType: 'application/json',
-          body: { error: errorMessage },
-        });
-      }
-
       if (contentType === 'text/html') {
         return request.respond({
           status: 200,

src/middleware/index.ts

@@ -3,3 +3,4 @@ export * from './withSpecValidation.js';
 export * from './withResponseHelpers.js';
 export * from './withContractFormat.js';
 export * from './withContractErrorHandler.js';
+export * from './withMissingHandler.js';

src/middleware/withContractErrorHandler.ts

@@ -23,25 +23,36 @@ export function withContractErrorHandler<
   RequestType extends IRequest = IRequest,
   Args extends any[] = any[],
 >(): (err: unknown, request: RequestType, ...args: Args) => Response {
-  return (err: unknown, request: RequestType, ..._args: Args): Response => {
+  return (err: unknown, _request: RequestType, ..._args: Args): Response => {
+    // Handle validation errors with issues array
     if (err instanceof Error && 'issues' in err) {
+      const issues = (err as Error & { issues: unknown }).issues;
       return new Response(
         JSON.stringify({
           error: 'Validation failed',
-          details: (err as Error & { issues: unknown }).issues,
+          details: Array.isArray(issues) ? issues : [issues],
         }),
         { status: 400, headers: { 'content-type': 'application/json' } }
       );
     }
 
-    // Handle other errors - return error message without circular reference issues
+    // Handle other errors - ensure all errors conform to { error: string, details: [...] }
     const errorMessage = err instanceof Error ? err.message : 'Internal server error';
     const statusCode =
       err && typeof err === 'object' && 'status' in err ? (err as any).status : 500;
 
+    // Format error message as a details array for consistency with validation errors
+    // Details array contains objects with message property (and optionally other fields)
+    const details = [
+      {
+        message: errorMessage,
+      },
+    ];
+
     return new Response(
       JSON.stringify({
         error: errorMessage,
+        details,
       }),
       { status: statusCode, headers: { 'content-type': 'application/json' } }
     );

src/middleware/withMissingHandler.ts

@@ -0,0 +1,47 @@
+import type { IRequest, ResponseHandler } from 'itty-router';
+import { error } from 'itty-router';
+import { createBasicResponseHelpers } from '../utils';
+
+/**
+ * Middleware for handling missing routes
+ *
+ * This middleware checks if a response has been set. If not, it calls the provided
+ * missing handler (if available) or returns a 404 error. The missing handler receives
+ * the request with basic response helpers attached.
+ *
+ * @typeParam RequestType - The request type (extends IRequest)
+ * @typeParam Args - Additional arguments passed to handlers
+ *
+ * @param missing - Optional handler for missing routes
+ * @returns A ResponseHandler function that handles missing routes
+ *
+ * @example
+ * ```typescript
+ * const router = Router({
+ *   finally: [
+ *     withMissingHandler(options.missing),
+ *   ],
+ * });
+ * ```
+ */
+export function withMissingHandler<
+  RequestType extends IRequest = IRequest,
+  Args extends any[] = any[],
+>(
+  missing?: (
+    request: RequestType & ReturnType<typeof createBasicResponseHelpers>,
+    ...args: Args
+  ) => Response | Promise<Response>
+): ResponseHandler {
+  return (response: Response, request: IRequest, ...args: Args) => {
+    if (response != null) return response as Response;
+    if (missing) {
+      return missing(
+        { ...(request as RequestType), ...createBasicResponseHelpers() } as RequestType &
+          ReturnType<typeof createBasicResponseHelpers>,
+        ...(args as Args)
+      );
+    }
+    return error(404);
+  };
+}

src/middleware/withSpecValidation.ts

@@ -1,111 +1,142 @@
 import type { IRequest, RequestHandler } from 'itty-router';
 import { error } from 'itty-router';
 import type { StandardSchemaV1 } from '@standard-schema/spec';
-import type { ContractAugmentedRequest } from '../types.js';
+import type {
+  ContractAugmentedRequest,
+  ContractOperationParameters,
+  ContractOperationQuery,
+} from '../types.js';
 import { validateSchema, defineProp } from '../utils.js';
 import {
   extractPathParamsFromUrl,
-  extractQueryParamsFromUrl,
   getContentType,
   parseBodyByContentType,
   normalizeHeaders,
   validateHeadersWithFallback,
 } from './utils.js';
 
-/**
- * Global middleware: Validates path parameters, query parameters, headers, and body
- * using the operation from request. This reads from __contractOperation set by
- * withMatchingContractOperation.
- *
- * This middleware combines the functionality of:
- * - withPathParams
- * - withQueryParams
- * - withHeaders
- * - withBody
- */
+type ContractOperation = NonNullable<ContractAugmentedRequest['__contractOperation']>;
+
 export const withSpecValidation: RequestHandler<IRequest> = async (request: IRequest) => {
   const operation = (request as ContractAugmentedRequest).__contractOperation;
   if (!operation) return;
 
-  // Validate path parameters
-  let requestParams = (request.params as Record<string, string> | undefined) || {};
-  if (!Object.keys(requestParams).length && request.url) {
-    requestParams = extractPathParamsFromUrl(operation.path, request.url);
-  }
-  const params = operation.pathParams
-    ? await validateSchema<Record<string, string>>(operation.pathParams, requestParams)
-    : requestParams;
-  defineProp(request, 'params', params);
+  // Path params
+  const params = await resolveAndValidatePathParams(request, operation);
+  defineProp(request, 'validatedParams', params);
 
-  // Validate query parameters
-  let requestQuery = (request.query as Record<string, unknown> | undefined) || {};
-  if (!Object.keys(requestQuery).length && request.url) {
-    requestQuery = extractQueryParamsFromUrl(request.url);
-  }
-  const query = operation.query
-    ? await validateSchema<Record<string, unknown>>(operation.query, requestQuery)
-    : requestQuery;
+  // Query params
+  const query = await resolveAndValidateQuery(request, operation);
   defineProp(request, 'validatedQuery', query);
-  defineProp(request, 'query', query);
-
-  // Validate headers
-  const requestHeaders = normalizeHeaders(request.headers);
-  const validatedHeadersObject = operation.headers
-    ? await validateHeadersWithFallback(operation.headers, requestHeaders)
-    : requestHeaders;
-  // Convert to Headers object to align with Web API Request standard
-  const headers = new Headers();
-  for (const [key, value] of Object.entries(validatedHeadersObject)) {
-    headers.set(key, String(value));
+
+  // Headers
+  const validatedHeaders = await resolveAndValidateHeaders(request, operation);
+  defineProp(request, 'validatedHeaders', validatedHeaders);
+
+  // Body
+  const validatedBody = await resolveAndValidateBody(request, operation);
+  defineProp(request, 'validatedBody', validatedBody);
+};
+
+async function resolveAndValidatePathParams(request: IRequest, operation: ContractOperation) {
+  const requestParams = extractPathParamsFromUrl(operation.path, request.url);
+
+  return operation.pathParams
+    ? await validateSchema<ContractOperationParameters<ContractOperation>>(
+        operation.pathParams,
+        requestParams
+      )
+    : requestParams;
+}
+
+async function resolveAndValidateQuery(
+  request: IRequest,
+  operation: ContractOperation
+): Promise<Record<string, unknown>> {
+  if (operation.query) {
+    return validateSchema<ContractOperationQuery<ContractOperation>>(
+      operation.query,
+      request.query
+    );
   }
-  defineProp(request, 'validatedHeaders', headers);
 
-  // Validate body
-  // If no request schemas defined, set empty body and return
-  if (!operation.requests) {
-    defineProp(request, 'validatedBody', {});
-    return;
+  return {};
+}
+
+async function resolveAndValidateHeaders(
+  request: IRequest,
+  operation: ContractOperation
+): Promise<Headers | undefined> {
+  if (operation.headers) {
+    const normalizedHeaders = normalizeHeaders(request.headers);
+    const validatedHeaders = await validateHeadersWithFallback(
+      operation.headers,
+      normalizedHeaders
+    );
+    return new Headers(validatedHeaders as Record<string, string>);
   }
 
-  let bodyData: unknown = {};
-  let bodyReadSuccessfully = false;
-  let bodyText = '';
+  return undefined;
+}
 
+async function tryReadRequestText(
+  request: IRequest
+): Promise<{ ok: true; text: string } | { ok: false }> {
   try {
-    bodyText = await request.text();
-    bodyReadSuccessfully = true;
+    const text = await request.text();
+    return { ok: true, text };
   } catch {
-    bodyData = {};
+    return { ok: false };
   }
+}
+
+function findRequestSchemaEntry(
+  requests: Record<string, unknown>,
+  contentType: string
+): [normalizedContentType: string, schema: unknown] | undefined {
+  // Slightly more robust than the original comment implied:
+  // - normalizes the incoming content type for matching (adds acceptance, doesn’t remove)
+  const normalized = contentType.toLowerCase();
 
-  if (bodyReadSuccessfully && bodyText.trim()) {
-    // Check if request is a content-type map
-    const contentType = getContentType(request);
-    if (!contentType) {
-      throw error(400, 'Content-Type header is required');
-    }
-
-    // Find matching schema (case-insensitive)
-    const matchingEntry = Object.entries(operation.requests).find(([key]) => {
-      return key.toLowerCase() === contentType;
-    });
-
-    if (!matchingEntry) {
-      throw error(
-        400,
-        `Unsupported Content-Type: ${contentType}. Supported types: ${Object.keys(operation.requests).join(', ')}`
-      );
-    }
-
-    const [, requestSchema] = matchingEntry;
-    if (!requestSchema || typeof requestSchema !== 'object' || !('body' in requestSchema)) {
-      throw error(500, 'Invalid request schema configuration');
-    }
-    bodyData = parseBodyByContentType(contentType, bodyText);
-    const body = await validateSchema((requestSchema as { body: StandardSchemaV1 }).body, bodyData);
-    defineProp(request, 'validatedBody', body);
-  } else {
-    // Empty body
-    defineProp(request, 'validatedBody', bodyData);
+  const entry = Object.entries(requests).find(([key]) => key.toLowerCase() === normalized);
+  if (!entry) return;
+
+  return [normalized, entry[1]];
+}
+
+async function resolveAndValidateBody(
+  request: IRequest,
+  operation: ContractOperation
+): Promise<unknown> {
+  // Preserve existing behavior: if no request schemas defined, set empty body.
+  if (!operation.requests) return {};
+
+  // Preserve existing behavior: body read failures become empty body.
+  const read = await tryReadRequestText(request);
+  if (!read.ok) return {};
+
+  const bodyText = read.text;
+  if (!bodyText.trim()) return {};
+
+  const contentType = getContentType(request);
+  if (!contentType) {
+    throw error(400, 'Content-Type header is required');
   }
-};
+
+  const entry = findRequestSchemaEntry(operation.requests, contentType);
+  if (!entry) {
+    throw error(
+      400,
+      `Unsupported Content-Type: ${contentType}. Supported types: ${Object.keys(operation.requests).join(', ')}`
+    );
+  }
+
+  const [normalizedContentType, requestSchema] = entry;
+
+  if (!requestSchema || typeof requestSchema !== 'object' || !('body' in requestSchema)) {
+    throw error(500, 'Invalid request schema configuration');
+  }
+
+  const bodyData = parseBodyByContentType(normalizedContentType, bodyText);
+  return await validateSchema((requestSchema as { body: StandardSchemaV1 }).body, bodyData);
+}