fix: save into cache under 304 response (#43)

* Fixed cache is not saved when response 304

* test: added test case for saving cache after 304 response
fix: set ava dependency to version 2.x instead of latest (ava 3.x breaks test cases)

* fix: test case should await cache.clear() promise to be fullfilled

Author: iKoala

index.js

@@ -114,18 +114,18 @@ module.exports = ({
       hasForce
     })
 
-    if (!isModified) {
-      res.statusCode = 304
-      res.end()
-      return
-    }
-
     if (!isHit) {
       const payload = { etag, createdAt, ttl, data, ...props }
       const value = await compress(payload)
       await cache.set(key, value, ttl)
     }
 
+    if (!isModified) {
+      res.statusCode = 304
+      res.end()
+      return
+    }
+
     return send({ data, res, req, ...props })
   }
 }

package.json

@@ -56,7 +56,7 @@
   "devDependencies": {
     "@commitlint/cli": "latest",
     "@commitlint/config-conventional": "latest",
-    "ava": "latest",
+    "ava": "~2.4.0",
     "ci-publish": "latest",
     "conventional-github-releaser": "latest",
     "coveralls": "latest",

test/index.js

@@ -4,6 +4,7 @@ import listen from 'test-listen'
 import micro from 'micro'
 import test from 'ava'
 import got from 'got'
+import Keyv from 'keyv'
 
 import cacheableResponse from '..'
 
@@ -259,3 +260,28 @@ test('return empty 304 response when If-None-Match matches ETag', async t => {
   t.is(statusCode, 304)
   t.is(body, '')
 })
+
+test('return HIT after empty 304 response', async t => {
+  const cache = new Keyv({ namespace: 'ssr' })
+  const url = await createServer({
+    cache,
+    get: ({ req, res }) => {
+      return {
+        data: { foo: 'bar' },
+        ttl: 10000,
+        createdAt: Date.now(),
+        foo: { bar: true }
+      }
+    },
+    send: ({ data, headers, res, req, ...props }) => {
+      res.end('Welcome to Micro')
+    }
+  })
+  const { headers: headersOne } = await got(`${url}/kikobeats`)
+  await cache.clear()
+  await got(`${url}/kikobeats`, {
+    headers: { 'If-None-Match': headersOne.etag }
+  })
+  const { headers: headersTwo } = await got(`${url}/kikobeats`)
+  t.is(headersTwo['x-cache-status'], 'HIT')
+})