feat: handle number and object responses correctly in functions (#440)

* chore: add package to output status messages

* feat: default to html api function response

* feat: handle res.json separately from res.send

* feat: handle number, boolean and object types with res.send

* test: update default content type for function responses

* test: add tests for new function responses

* chore: update package-lock files

Author: orinokai

demo/package-lock.json

@@ -56,6 +56,7 @@
     "pathe": "^0.3.0",
     "pretty-bytes": "^5.6.0",
     "semver": "^7.3.5",
+    "statuses": "^2.0.1",
     "tempy": "^1.0.0",
     "uuid": "^8.3.2"
   },

plugin/package-lock.json

@@ -13,6 +13,7 @@ import cookie from 'cookie'
 import type { GatsbyFunctionResponse } from 'gatsby'
 import { GatsbyFunctionRequest } from 'gatsby'
 import fetch, { Headers } from 'node-fetch'
+import statuses from 'statuses'
 
 interface NetlifyFunctionParams {
   event: HandlerEvent
@@ -133,7 +134,7 @@ export const createResponseObject = ({ onResEnd }) => {
       response.statusCode = statusCode
     },
   })
-  res.headers = { 'content-type': 'text/plain; charset=utf-8' }
+  res.headers = { 'content-type': 'text/html; charset=utf-8' }
 
   res.writeHead = (status, headers) => {
     response.statusCode = status
@@ -207,6 +208,22 @@ export const createResponseObject = ({ onResEnd }) => {
     if (res.finished) {
       return res
     }
+
+    if (typeof data === 'number') {
+      return res
+        .status(data)
+        .setHeader('content-type', 'text/plain; charset=utf-8')
+        .end(statuses.message[data] || String(data))
+    }
+
+    if (typeof data === 'boolean' || typeof data === 'object') {
+      if (Buffer.isBuffer(data)) {
+        res.setHeader('content-type', 'application/octet-stream')
+      } else if (data !== null) {
+        return res.json(data)
+      }
+    }
+
     res.end(data)
     return res
   }
@@ -216,7 +233,7 @@ export const createResponseObject = ({ onResEnd }) => {
       return res
     }
     res.setHeader('content-type', 'application/json')
-    res.send(JSON.stringify(data))
+    res.end(JSON.stringify(data))
     return res
   }
 

plugin/package.json

@@ -117,13 +117,38 @@ exports.runTests = function runTests(env, host) {
         })
         expect(res.headers.get('content-type')).toEqual('application/json')
       })
+      test(`returns json correctly via send`, async () => {
+        const res = await fetchTwice(`${host}/api/i-am-json-too`)
+        const result = await res.json()
+
+        expect(result).toEqual({
+          amIJSON: true,
+        })
+        expect(res.headers.get('content-type')).toEqual('application/json')
+      })
+      test(`returns boolean correctly via send`, async () => {
+        const res = await fetchTwice(`${host}/api/i-am-false`)
+        const result = await res.json()
+
+        expect(result).toEqual(false)
+        expect(res.headers.get('content-type')).toEqual('application/json')
+      })
+      test(`returns status correctly via send`, async () => {
+        const res = await fetchTwice(`${host}/api/i-am-status`)
+        const result = await res.text()
+
+        expect(result).toEqual('OK')
+        expect(res.headers.get('content-type')).toEqual(
+          'text/plain; charset=utf-8',
+        )
+      })
       test(`returns text correctly`, async () => {
         const res = await fetchTwice(`${host}/api/i-am-text`)
         const result = await res.text()
 
         expect(result).toEqual('I am text')
         expect(res.headers.get('content-type')).toEqual(
-          'text/plain; charset=utf-8',
+          'text/html; charset=utf-8',
         )
       })
     })

plugin/src/templates/api/utils.ts

@@ -0,0 +1,3 @@
+export default function topLevel(req, res) {
+  res.send(false)
+}

plugin/test/fixtures/functions-without-gatsby-plugin/e2e-tests/test-helpers.js

@@ -0,0 +1,3 @@
+export default function topLevel(req, res) {
+  res.send({ amIJSON: true })
+}

plugin/test/fixtures/functions-without-gatsby-plugin/src/api/i-am-false.js

@@ -0,0 +1,3 @@
+export default function topLevel(req, res) {
+  res.send(200)
+}