Check Redis cache inside of process mutex

server/utils/fetchPackageInfo.js

@@ -3,26 +3,22 @@ require("isomorphic-fetch");
 const config = require("../config");
 
 function fetchPackageInfo(packageName) {
-  return new Promise(resolve => {
+  let encodedPackageName;
-    let encodedPackageName;
+  if (packageName.charAt(0) === "@") {
-    if (packageName.charAt(0) === "@") {
+    encodedPackageName = `@${encodeURIComponent(packageName.substring(1))}`;
-      encodedPackageName = `@${encodeURIComponent(packageName.substring(1))}`;
+  } else {
-    } else {
+    encodedPackageName = encodeURIComponent(packageName);
-      encodedPackageName = encodeURIComponent(packageName);
+  }
+
+  const url = `${config.registryURL}/${encodedPackageName}`;
+
+  console.log(`info: Fetching package info from ${url}`);
+
+  return fetch(url, {
+    headers: {
+      Accept: "application/json"
     }
-
+  }).then(res => (res.status === 404 ? null : res.json()));
-    const url = `${config.registryURL}/${encodedPackageName}`;
-
-    console.log(`info: Fetching package info from ${url}`);
-
-    resolve(
-      fetch(url, {
-        headers: {
-          Accept: "application/json"
-        }
-      }).then(res => (res.status === 404 ? null : res.json()))
-    );
-  });
 }
 
 module.exports = fetchPackageInfo;

server/utils/getPackageInfo.js

@@ -2,53 +2,51 @@ const createCache = require("./createCache");
 const createMutex = require("./createMutex");
 const fetchPackageInfo = require("./fetchPackageInfo");
 
-const packageInfoCache = createCache("packageInfo");
+const cache = createCache("packageInfo");
-const packageNotFound = "PackageNotFound";
+const notFound = "PackageNotFound";
 
-// This mutex prevents multiple concurrent requests to
-// the registry for the same package info.
 const fetchMutex = createMutex((packageName, callback) => {
-  fetchPackageInfo(packageName).then(
+  cache.get(packageName, (error, value) => {
-    value => {
+    if (error) {
-      if (value == null) {
+      callback(error);
-        // Cache 404s for 5 minutes. This prevents us from making
+    } else if (value != null) {
-        // unnecessary requests to the registry for bad package names.
+      callback(null, value === notFound ? null : value);
-        // In the worst case, a brand new package's info will be
+    } else {
-        // available within 5 minutes.
+      fetchPackageInfo(packageName).then(
-        packageInfoCache.set(packageName, packageNotFound, 300, () => {
+        value => {
-          callback(null, value);
+          if (value == null) {
-        });
+            // Cache 404s for 5 minutes. This prevents us from making
-      } else {
+            // unnecessary requests to the registry for bad package names.
-        // Cache valid package info for 1 minute.
+            // In the worst case, a brand new package's info will be
-        packageInfoCache.set(packageName, value, 60, () => {
+            // available within 5 minutes.
-          callback(null, value);
+            cache.set(packageName, notFound, 300, () => {
-        });
+              callback(null, value);
-      }
+            });
-    },
+          } else {
-    error => {
+            // Cache valid package info for 1 minute.
-      // Do not cache errors.
+            cache.set(packageName, value, 60, () => {
-      packageInfoCache.del(packageName, () => {
+              callback(null, value);
-        callback(error);
+            });
-      });
+          }
+        },
+        error => {
+          // Do not cache errors.
+          cache.del(packageName, () => {
+            callback(error);
+          });
+        }
+      );
     }
-  );
+  });
 });
 
 function getPackageInfo(packageName) {
   return new Promise((resolve, reject) => {
-    packageInfoCache.get(packageName, (error, value) => {
+    fetchMutex(packageName, (error, value) => {
       if (error) {
         reject(error);
-      } else if (value != null) {
-        resolve(value === packageNotFound ? null : value);
       } else {
-        fetchMutex(packageName, (error, value) => {
+        resolve(value);
-          if (error) {
-            reject(error);
-          } else {
-            resolve(value);
-          }
-        });
       }
     });
   });