openapi3 support

Author: ajaishankar

src/fetcher.ts

@@ -82,6 +82,12 @@ function getHeaders(init?: HeadersInit) {
   return headers
 }
 
+function getBody(method: Method, payload: Record<string, unknown>) {
+  const body = sendBody(method) ? JSON.stringify(payload) : undefined
+  // if delete don't send body if empty
+  return method === 'delete' && body === '{}' ? undefined : body
+}
+
 function mergeRequestInit(
   first?: RequestInit,
   second?: RequestInit,
@@ -110,7 +116,7 @@ function getFetchParams(request: Request) {
     ...request.init,
     method: request.method.toUpperCase(),
     headers,
-    body: sendBody(request.method) ? JSON.stringify(payload) : undefined,
+    body: getBody(request.method, payload),
   }
 
   return { url, init }

src/index.ts

@@ -6,13 +6,15 @@ import type {
   FetchReturnType,
   Middleware,
   OpArgType,
+  OpDefaultReturnType,
   OpReturnType,
 } from './types'
 
 import { ApiError } from './types'
 
 export type {
   OpArgType,
+  OpDefaultReturnType,
   OpReturnType,
   FetchArgType,
   FetchReturnType,

src/types.ts

@@ -14,34 +14,47 @@ export type OpenapiPaths<Paths> = {
 }
 
 export type OpArgType<OP> = OP extends {
-  parameters: {
+  parameters?: {
     path?: infer P
     query?: infer Q
     body?: infer B
   }
+  // openapi 3
+  requestBody?: {
+    content: {
+      'application/json': infer RB
+    }
+  }
 }
-  ? P & Q & (B extends Record<string, unknown> ? B[keyof B] : unknown)
+  ? P & Q & (B extends Record<string, unknown> ? B[keyof B] : unknown) & RB
   : Record<string, never>
 
-// openapi 2 response type
-export type OpReturnType<OP> = OP extends {
+export type OpDefaultReturnType<OP> = OP extends {
   responses: {
-    200: {
-      schema: infer R
-    }
+    default: infer D
   }
 }
-  ? R
-  : OP extends {
-      responses: {
-        default: infer D
-      }
-    }
   ? D extends { schema: infer S }
     ? S
+    : D extends { content: { 'application/json': infer C } } // openapi 3
+    ? C
     : D
   : unknown
 
+export type OpReturnType<OP> = OP extends {
+  responses: {
+    200: {
+      schema?: infer R
+      // openapi 3
+      content?: {
+        'application/json': infer C
+      }
+    }
+  }
+}
+  ? R & C
+  : OpDefaultReturnType<OP>
+
 export type CustomRequestInit = Omit<RequestInit, 'headers'> & {
   readonly headers: Headers
 }
@@ -64,7 +77,7 @@ type _CreateFetch<OP, Q = never> = [Q] extends [never]
   ? () => TypedFetch<OpReturnType<OP>, OpArgType<OP>>
   : (query: Q) => TypedFetch<OpReturnType<OP>, OpArgType<OP>>
 
-export type CreateFetch<M, OP> = M extends 'post' | 'put' | 'patch'
+export type CreateFetch<M, OP> = M extends 'post' | 'put' | 'patch' | 'delete'
   ? OP extends { parameters: { query: infer Q } }
     ? _CreateFetch<OP, { [K in keyof Q]: true | 1 }>
     : _CreateFetch<OP>