feat(createendpoint): allow to omit the input property (#16)

In cases when there's no input, like on GET requests, you can omit the input object and the OAS will
not render it

src/lib/create-app.ts

@@ -78,9 +78,10 @@ function wrapWithRescueAndValidation<T extends Routing>(routing: T) {
         Object.entries(route).map(([method, endpoint]) => {
           const handlers = Array.isArray(endpoint.handlers) ? endpoint.handlers : [endpoint.handlers]
           const rescuedHandlers = handlers.map(rescue)
+          const finalHandlers = endpoint.input ? [validate(endpoint.input), ...rescuedHandlers] : rescuedHandlers
           const wrappedRouteDef = {
             ...endpoint,
-            handlers: [validate(endpoint.input), ...rescuedHandlers],
+            handlers: finalHandlers,
           }
           return [method, wrappedRouteDef]
         }),

src/lib/create-endpoint.ts

@@ -6,9 +6,7 @@ import {
   type ParameterLocation,
   type ResponseObject,
 } from 'openapi3-ts/oas31'
-import { z, type ZodObject, type ZodTypeAny } from 'zod'
-
-const emptySchema = z.object({})
+import { type z, type ZodObject, type ZodTypeAny } from 'zod'
 
 export type OneOrMore<T> = T | T[]
 export type ValueOf<T> = T[keyof T]
@@ -44,7 +42,7 @@ export type Endpoint<
   ResponseBodies extends ResponseMap = any,
 > = OperationObject & {
   handlers: OneOrMore<Handler<RequestBody, Params, Query, ResponseBodies>>
-  input: {
+  input?: {
     body?: ZodObject<any, 'strip', ZodTypeAny, RequestBody, any>
     params?: ZodObject<any, 'strip', ZodTypeAny, Params, any>
     query?: ZodObject<any, 'strip', ZodTypeAny, Query, any>
@@ -58,7 +56,7 @@ export type EndpointParams<
   Query,
   ResponseBodies extends ResponseMap,
 > = Partial<OperationObject> & {
-  input: {
+  input?: {
     body?: ZodObject<any, 'strip', ZodTypeAny, RequestBody, any>
     params?: ZodObject<any, 'strip', ZodTypeAny, Params, any>
     query?: ZodObject<any, 'strip', ZodTypeAny, Query, any>
@@ -96,8 +94,8 @@ export function createEndpoint<RequestBody, Params, Query, ResponseBodies extend
 
   const responses = Object.fromEntries(Object.entries(output).map(getResponseFromOutput))
 
-  const inputParams: Record<string, unknown> = input.params ? input.params._def.shape() : {}
-  const inputQuery: Record<string, unknown> = input.query ? input.query._def.shape() : {}
+  const inputParams: Record<string, unknown> = input?.params ? input.params._def.shape() : {}
+  const inputQuery: Record<string, unknown> = input?.query ? input.query._def.shape() : {}
   const params = [
     ...Object.entries(inputParams).map(
       ([key, value]) => ({
@@ -111,7 +109,7 @@ export function createEndpoint<RequestBody, Params, Query, ResponseBodies extend
         in: 'query' as const,
         schema: generateSchema(value as ZodTypeAny),
       })),
-      ...Object.entries(input.headers ?? {}).map(([key, value]) => ({
+      ...Object.entries(input?.headers ?? {}).map(([key, value]) => ({
         name: key,
         in: 'header' as ParameterLocation,
         schema: { type: 'string' as const },
@@ -124,13 +122,7 @@ export function createEndpoint<RequestBody, Params, Query, ResponseBodies extend
     ...openApiParams,
     responses,
     parameters: params,
-    requestBody: {
-      content: {
-        'application/json': {
-          schema: generateSchema(input.body ?? emptySchema),
-        },
-      },
-    },
+    requestBody: input?.body ? { content: { 'application/json': { schema: generateSchema(input.body) } } } : undefined,
     handlers,
     input,
     output,

usage/index.ts

@@ -141,6 +141,18 @@ const dummy = createEndpoint({
   },
 })
 
+const noInput = createEndpoint({
+  description: 'This is a dummy endpoint with no input',
+  output: {
+    200: {
+      body: z.object({ ok: z.boolean() }),
+    },
+  },
+  handlers: (_req, res, _next) => {
+    res.status(200).json({ ok: true })
+  },
+})
+
 const routing: Routing = {
   '/users': {
     post: createUser,
@@ -151,6 +163,9 @@ const routing: Routing = {
   '/dummy': {
     post: dummy,
   },
+  '/no-input': {
+    post: noInput,
+  },
 }
 
 const openApiInfo: OpenApiInfo = {