fix(adapter/aws-lambda): use content-encoding to determine isBase64En…

…coded (#1295)

* aws-lambda adapter: use content-encoding to determine isBase64Encoded

* when contentType is binary, skip checking contentEncoding

* prettier

src/adapter/aws-lambda/handler.test.ts

@@ -1,4 +1,4 @@
-import { isContentTypeBinary } from './handler'
+import { isContentTypeBinary, isContentEncodingBinary } from './handler'
 
 describe('isContentTypeBinary', () => {
   it('Should determine whether it is binary', () => {
@@ -13,3 +13,15 @@ describe('isContentTypeBinary', () => {
     expect(isContentTypeBinary('application/json; charset=UTF-8')).toBe(false)
   })
 })
+
+describe('isContentEncodingBinary', () => {
+  it('Should determine whether it is compressed', () => {
+    expect(isContentEncodingBinary('gzip')).toBe(true)
+    expect(isContentEncodingBinary('compress')).toBe(true)
+    expect(isContentEncodingBinary('deflate')).toBe(true)
+    expect(isContentEncodingBinary('br')).toBe(true)
+    expect(isContentEncodingBinary('deflate, gzip')).toBe(true)
+    expect(isContentEncodingBinary('')).toBe(false)
+    expect(isContentEncodingBinary('unknown')).toBe(false)
+  })
+})

src/adapter/aws-lambda/handler.ts

@@ -60,7 +60,9 @@ interface APIGatewayProxyResult {
 /**
  * Accepts events from API Gateway/ELB(`APIGatewayProxyEvent`) and directly through Function Url(`APIGatewayProxyEventV2`)
  */
-export const handle = <E extends Env = Env, S = {}, BasePath extends string = '/'>(app: Hono<E, S, BasePath>) => {
+export const handle = <E extends Env = Env, S = {}, BasePath extends string = '/'>(
+  app: Hono<E, S, BasePath>
+) => {
   return async (
     event: APIGatewayProxyEvent | APIGatewayProxyEventV2 | LambdaFunctionUrlEvent
   ): Promise<APIGatewayProxyResult> => {
@@ -73,7 +75,12 @@ export const handle = <E extends Env = Env, S = {}, BasePath extends string = '/
 
 const createResult = async (res: Response): Promise<APIGatewayProxyResult> => {
   const contentType = res.headers.get('content-type')
-  const isBase64Encoded = contentType && isContentTypeBinary(contentType) ? true : false
+  let isBase64Encoded = contentType && isContentTypeBinary(contentType) ? true : false
+
+  if (!isBase64Encoded) {
+    const contentEncoding = res.headers.get('content-encoding')
+    isBase64Encoded = isContentEncodingBinary(contentEncoding)
+  }
 
   let body: string
   if (isBase64Encoded) {
@@ -153,3 +160,10 @@ export const isContentTypeBinary = (contentType: string) => {
     contentType
   )
 }
+
+export const isContentEncodingBinary = (contentEncoding: string | null) => {
+  if (contentEncoding === null) {
+    return false
+  }
+  return /^(gzip|deflate|compress|br)/.test(contentEncoding)
+}