I think I have it working with failing tests

Author: dac09

packages/api/src/__tests__/normalizeRequest.test.ts

@@ -3,7 +3,7 @@ import type { APIGatewayProxyEvent } from 'aws-lambda'
 
 import { normalizeRequest } from '../transforms'
 
-export const createMockedEvent = (
+export const createMockedLambdaEvent = (
   httpMethod = 'POST',
   body: any = undefined,
   isBase64Encoded = false
@@ -53,41 +53,78 @@ export const createMockedEvent = (
   }
 }
 
-test('Normalizes an aws event with base64', () => {
-  const corsEventB64 = createMockedEvent(
-    'POST',
-    Buffer.from(JSON.stringify({ bazinga: 'hello_world' }), 'utf8').toString(
-      'base64'
-    ),
-    true
-  )
+describe('Lambda Request', () => {
+  it('Normalizes an aws event with base64', async () => {
+    const corsEventB64 = createMockedLambdaEvent(
+      'POST',
+      Buffer.from(JSON.stringify({ bazinga: 'hello_world' }), 'utf8').toString(
+        'base64'
+      ),
+      true
+    )
 
-  expect(normalizeRequest(corsEventB64)).toEqual({
-    headers: new Headers(corsEventB64.headers),
-    method: 'POST',
-    query: null,
-    body: {
-      bazinga: 'hello_world',
-    },
+    expect(await normalizeRequest(corsEventB64)).toEqual({
+      headers: new Headers(corsEventB64.headers as Record<string, string>),
+      method: 'POST',
+      query: null,
+      jsonBody: {
+        bazinga: 'hello_world',
+      },
+    })
   })
-})
 
-test('Handles CORS requests with and without b64 encoded', () => {
-  const corsEventB64 = createMockedEvent('OPTIONS', undefined, true)
+  it('Handles CORS requests with and without b64 encoded', async () => {
+    const corsEventB64 = createMockedLambdaEvent('OPTIONS', undefined, true)
+
+    expect(await normalizeRequest(corsEventB64)).toEqual({
+      headers: new Headers(corsEventB64.headers as Record<string, string>), // headers returned as symbol
+      method: 'OPTIONS',
+      query: null,
+      jsonBody: undefined,
+    })
+
+    const corsEventWithoutB64 = createMockedLambdaEvent(
+      'OPTIONS',
+      undefined,
+      false
+    )
 
-  expect(normalizeRequest(corsEventB64)).toEqual({
-    headers: new Headers(corsEventB64.headers), // headers returned as symbol
-    method: 'OPTIONS',
-    query: null,
-    body: undefined,
+    expect(await normalizeRequest(corsEventWithoutB64)).toEqual({
+      headers: new Headers(corsEventB64.headers as Record<string, string>), // headers returned as symbol
+      method: 'OPTIONS',
+      query: null,
+      jsonBody: undefined,
+    })
   })
+})
+
+describe('Fetch API Request', () => {
+  it('Normalizes a fetch event', async () => {
+    const fetchEvent = new Request(
+      'http://localhost:9210/graphql?whatsup=doc&its=bugs',
+      {
+        method: 'POST',
+        headers: {
+          'content-type': 'application/json',
+        },
+        body: JSON.stringify({ bazinga: 'kittens_purr_purr' }),
+      }
+    )
+
+    const partial = await normalizeRequest(fetchEvent)
 
-  const corsEventWithoutB64 = createMockedEvent('OPTIONS', undefined, false)
+    expect(partial).toMatchObject({
+      // headers: fetchEvent.headers,
+      method: 'POST',
+      query: {
+        whatsup: 'doc',
+        its: 'bugs',
+      },
+      jsonBody: {
+        bazinga: 'kittens_purr_purr',
+      },
+    })
 
-  expect(normalizeRequest(corsEventWithoutB64)).toEqual({
-    headers: new Headers(corsEventB64.headers), // headers returned as symbol
-    method: 'OPTIONS',
-    query: null,
-    body: undefined,
+    expect(partial.headers.get('content-type')).toEqual('application/json')
   })
 })

packages/api/src/cors.ts

@@ -1,6 +1,6 @@
 import { Headers } from '@whatwg-node/fetch'
 
-import type { Request } from './transforms'
+import type { PartialRequest } from './transforms'
 
 export type CorsConfig = {
   origin?: boolean | string | string[]
@@ -59,10 +59,10 @@ export function createCorsContext(cors: CorsConfig | undefined) {
   }
 
   return {
-    shouldHandleCors(request: Request) {
+    shouldHandleCors(request: PartialRequest) {
       return request.method === 'OPTIONS'
     },
-    getRequestHeaders(request: Request): CorsHeaders {
+    getRequestHeaders(request: PartialRequest): CorsHeaders {
       const eventHeaders = new Headers(request.headers as HeadersInit)
       const requestCorsHeaders = new Headers(corsHeaders)
 

packages/api/src/transforms.ts

@@ -1,10 +1,11 @@
-import { Headers } from '@whatwg-node/fetch'
+import { Headers, Request as PonyFillRequest } from '@whatwg-node/fetch'
 import type { APIGatewayProxyEvent } from 'aws-lambda'
 
-// This is the same interface used by GraphQL Yoga
-// But not importing here to avoid adding a dependency
-export interface Request {
-  body?: any
+// This is part of the request, dreived either from a LambdaEvent or FetchAPI Request
+// We do this to keep the API consistent between the two
+// When we support only the FetchAPI request, we should remove this
+export interface PartialRequest<TBody = Record<string, any>> {
+  jsonBody?: TBody
   headers: Headers
   method: string
   query: any
@@ -13,7 +14,7 @@ export interface Request {
 /**
  * Extracts and parses body payload from event with base64 encoding check
  */
-export const parseEventBody = (event: APIGatewayProxyEvent) => {
+export const parseLambdaEventBody = (event: APIGatewayProxyEvent) => {
   if (!event.body) {
     return
   }
@@ -25,14 +26,47 @@ export const parseEventBody = (event: APIGatewayProxyEvent) => {
   }
 }
 
-export function normalizeRequest(event: APIGatewayProxyEvent): Request {
-  const body = parseEventBody(event)
+export const isFetchApiRequest = (event: any): event is Request => {
+  return event instanceof Request || event instanceof PonyFillRequest
+}
+
+function getQueryStringParams(reqUrl: string) {
+  const url = new URL(reqUrl)
+  const params = new URLSearchParams(url.search)
+
+  const paramObject: Record<string, string> = {}
+  for (const entry of params.entries()) {
+    paramObject[entry[0]] = entry[1] // each 'entry' is a [key, value] tuple
+  }
+  return paramObject
+}
+
+/**
+ *
+ * This function returns a an object that lets you access _some_ of the request properties in a consistent way
+ * You can give it either a LambdaEvent or a Fetch API Request
+ *
+ * NOTE: It does NOT return a full Request object!
+ */
+export async function normalizeRequest(
+  event: APIGatewayProxyEvent | Request
+): Promise<PartialRequest> {
+  if (isFetchApiRequest(event)) {
+    return {
+      headers: event.headers,
+      method: event.method,
+      query: getQueryStringParams(event.url),
+      jsonBody: await event.json(),
+    }
+  }
+
+  const jsonBody = parseLambdaEventBody(event)
 
   return {
     headers: new Headers(event.headers as Record<string, string>),
     method: event.httpMethod,
     query: event.queryStringParameters,
-    body,
+    jsonBody,
   }
 }