Merge pull request #10 from jkyberneees/improve-error-handling

Improve error handling

Author: jkyberneees

README.md

@@ -154,4 +154,7 @@ This is your repo ;)
 > Note: We aim to be 100% code coverage, please consider it on your pull requests.
 
 ## Related projects
-- fast-gateway (https://www.npmjs.com/package/fast-gateway)
+- fast-gateway (https://www.npmjs.com/package/fast-gateway)
+
+## Sponsors
+- Kindly sponsored by [ShareNow](https://www.share-now.com/), a company that promotes innovation!  

index.js

@@ -13,96 +13,96 @@ const CACHE_CONTROL = 'cache-control'
 const CACHE_IF_NONE_MATCH = 'if-none-match'
 
 const middleware = (opts) => async (req, res, next) => {
-  opts = Object.assign({
-    stores: [CacheManager.caching({ store: 'memory', max: 1000, ttl: 30 })]
-  }, opts)
+  try {
+    opts = Object.assign({
+      stores: [CacheManager.caching({ store: 'memory', max: 1000, ttl: 30 })]
+    }, opts)
 
-  // creating multi-cache instance
-  const mcache = CacheManager.multiCaching(opts.stores)
+    // creating multi-cache instance
+    const mcache = CacheManager.multiCaching(opts.stores)
 
-  if (req.cacheDisabled) return next()
+    if (req.cacheDisabled) return next()
 
-  let { url, cacheAppendKey = req => '' } = req
-  cacheAppendKey = await cacheAppendKey(req)
+    let { url, cacheAppendKey = req => '' } = req
+    cacheAppendKey = await cacheAppendKey(req)
 
-  const key = req.method + url + cacheAppendKey
-  // ref cache key on req object
-  req.cacheKey = key
+    const key = req.method + url + cacheAppendKey
+    // ref cache key on req object
+    req.cacheKey = key
 
-  // try to retrieve cached response
-  const cached = await get(mcache, key)
+    // try to retrieve cached response
+    const cached = await get(mcache, key)
 
-  if (cached) {
-    // respond from cache if there is a hit
-    let { status, headers, data } = JSON.parse(cached)
+    if (cached) {
+      // respond from cache if there is a hit
+      let { status, headers, data } = JSON.parse(cached)
 
-    // pre-checking If-None-Match header
-    if (req.headers[CACHE_IF_NONE_MATCH] && req.headers[CACHE_IF_NONE_MATCH] === headers[CACHE_ETAG]) {
-      res.setHeader('content-length', '0')
-      res.statusCode = 304
-      res.end()
+      // pre-checking If-None-Match header
+      if (req.headers[CACHE_IF_NONE_MATCH] && req.headers[CACHE_IF_NONE_MATCH] === headers[CACHE_ETAG]) {
+        res.setHeader('content-length', '0')
+        res.statusCode = 304
+        res.end()
 
-      return // exit because client cache state matches
-    }
+        return // exit because client cache state matches
+      }
 
-    if (typeof data === 'object' && data.type === 'Buffer') {
-      data = Buffer.from(data.data)
-    }
-    headers[X_CACHE_HIT] = '1'
+      if (typeof data === 'object' && data.type === 'Buffer') {
+        data = Buffer.from(data.data)
+      }
+      headers[X_CACHE_HIT] = '1'
 
-    // set cached response headers
-    Object.keys(headers).forEach(header => res.setHeader(header, headers[header]))
+      // set cached response headers
+      Object.keys(headers).forEach(header => res.setHeader(header, headers[header]))
 
-    // send cached payload
-    req.cacheHit = true
-    res.statusCode = status
-    res.end(data)
+      // send cached payload
+      req.cacheHit = true
+      res.statusCode = status
+      res.end(data)
 
-    return
-  }
+      return
+    }
 
-  onEnd(res, (payload) => {
-    if (payload.headers[X_CACHE_EXPIRE]) {
-      // support service level expiration
-      const keysPattern = payload.headers[X_CACHE_EXPIRE].replace(/\s/g, '')
-      const patterns = keysPattern.split(',')
-      // delete keys on all cache tiers
-      patterns.forEach(pattern => opts.stores.forEach(store => getKeys(store, pattern).then(keys => mcache.del(keys))))
-    } else if (payload.headers[X_CACHE_TIMEOUT] || payload.headers[CACHE_CONTROL]) {
-      // extract cache ttl
-      let ttl = 0
-      if (payload.headers[CACHE_CONTROL]) {
-        ttl = cacheControl(payload.headers[CACHE_CONTROL]).maxAge
-      }
-      if (!ttl) {
-        if (payload.headers[X_CACHE_TIMEOUT]) {
-          ttl = Math.max(ms(payload.headers[X_CACHE_TIMEOUT]), 1000) / 1000 // min value: 1 second
-        } else {
-          return // no TTL found, we don't cache
+    onEnd(res, (payload) => {
+      if (payload.headers[X_CACHE_EXPIRE]) {
+        // support service level expiration
+        const keysPattern = payload.headers[X_CACHE_EXPIRE].replace(/\s/g, '')
+        const patterns = keysPattern.split(',')
+        // delete keys on all cache tiers
+        patterns.forEach(pattern => opts.stores.forEach(store => getKeys(store, pattern).then(keys => mcache.del(keys))))
+      } else if (payload.headers[X_CACHE_TIMEOUT] || payload.headers[CACHE_CONTROL]) {
+        // extract cache ttl
+        let ttl = 0
+        if (payload.headers[CACHE_CONTROL]) {
+          ttl = cacheControl(payload.headers[CACHE_CONTROL]).maxAge
+        }
+        if (!ttl) {
+          if (payload.headers[X_CACHE_TIMEOUT]) {
+            ttl = Math.max(ms(payload.headers[X_CACHE_TIMEOUT]), 1000) / 1000 // min value: 1 second
+          } else {
+            return // no TTL found, we don't cache
+          }
         }
-      }
 
-      // setting cache-control header if absent
-      if (!payload.headers[CACHE_CONTROL]) {
-        payload.headers[CACHE_CONTROL] = `private, no-cache, max-age=${ttl}`
-      }
-      // setting ETag if absent
-      if (!payload.headers[CACHE_ETAG]) {
-        payload.headers[CACHE_ETAG] = Math.random().toString(36).substring(2, 16)
-      }
+        // setting cache-control header if absent
+        if (!payload.headers[CACHE_CONTROL]) {
+          payload.headers[CACHE_CONTROL] = `private, no-cache, max-age=${ttl}`
+        }
+        // setting ETag if absent
+        if (!payload.headers[CACHE_ETAG]) {
+          payload.headers[CACHE_ETAG] = Math.random().toString(36).substring(2, 16)
+        }
 
-      // cache response
-      mcache.set(req.cacheKey, JSON.stringify(payload), { ttl })
-    }
-  })
+        // cache response
+        mcache.set(req.cacheKey, JSON.stringify(payload), { ttl })
+      }
+    })
 
-  return next()
+    return next()
+  } catch (err) {
+    return next(err)
+  }
 }
 
-const get = (cache, key) => new Promise((resolve) => {
-  cache.getAndPassUp(key, (_, res) => {
-    resolve(res)
-  })
-})
+const get = (cache, key) => cache.getAndPassUp(key)
 
 module.exports = iu(middleware)

package-lock.json

@@ -1,6 +1,6 @@
 {
   "name": "http-cache-middleware",
-  "version": "1.2.4",
+  "version": "1.2.5",
   "description": "HTTP Cache Middleware",
   "main": "index.js",
   "scripts": {