fix(redisSessions): improve redis session lookup performance (#2026) r=vladikoff,rfk

Fixes #2025

lib/db.js

@@ -270,9 +270,9 @@ module.exports = (
         }
         // for each db session token, if there is a matching redis token
         // overwrite the properties of the db token with the redis token values
-        const redisSessionTokens = redisTokens ? JSON.parse(redisTokens) : []
+        const redisSessionTokens = redisTokens ? JSON.parse(redisTokens) : {}
         const sessions = mysqlSessionTokens.map((sessionToken) => {
-          const redisToken = redisSessionTokens.find(tok => tok.tokenId === sessionToken.tokenId)
+          const redisToken = redisSessionTokens[sessionToken.tokenId]
           const mergedToken = Object.assign({}, sessionToken, redisToken)
           return mergedToken
         })
@@ -431,7 +431,7 @@ module.exports = (
     }
     return P.all(promises)
       .spread((devices, redisTokens) => {
-        const redisSessionTokens = redisTokens ? JSON.parse(redisTokens) : []
+        const redisSessionTokens = redisTokens ? JSON.parse(redisTokens) : {}
         log.info({
           op: 'db.devices.redisSessionTokens',
           hasRedisTokens: !! redisSessionTokens.length,
@@ -440,7 +440,7 @@ module.exports = (
         // for each device, if there is a redis token with a matching tokenId
         // overwrite device's ua properties and lastAccessTime with redis token values
         return devices.map(device => {
-          const token = redisSessionTokens.find(tok => tok.tokenId === device.sessionTokenId)
+          const token = redisSessionTokens[device.sessionTokenId]
           const mergedInfo = Object.assign({}, device, token)
           return {
             id: device.id,
@@ -513,18 +513,16 @@ module.exports = (
       lastAccessTime: token.lastAccessTime,
       createdAt: token.createdAt
     }]
-    let sessionTokens = []
-    // get the array of session tokens associated with the given uid
+    let sessionTokens
+    // get the object of session tokens associated with the given uid
     return this.redis.getAsync(uid)
     .then(res => {
-      if (res) {
-        res = JSON.parse(res)
-        // remove the token that we want to update from the array
-        const filteredRes = res.filter(tok => tok.tokenId !== token.id)
-        sessionTokens = sessionTokens.concat(filteredRes)
-      }
-      // add new updated token into array, and set the resulting array as the new value
-      sessionTokens = sessionTokens.concat(newToken)
+      // update the hash with the new token
+      sessionTokens = res ? JSON.parse(res) : {}
+      sessionTokens[token.id] = newToken
+      return sessionTokens
+    })
+    .then(() => {
       return this.redis.setAsync(uid, JSON.stringify(sessionTokens))
     })
     .then(() => sessionTokens)
@@ -654,9 +652,8 @@ module.exports = (
     }
     return P.all(promises)
       .spread((deleteRes, redisTokens) => {
-        const redisSessionTokens = redisTokens ? JSON.parse(redisTokens) : []
-        const tokenToDeleteIndex = redisSessionTokens.findIndex((tok) => tok.tokenId === sessionToken.id)
-        redisSessionTokens.splice(tokenToDeleteIndex, 1)
+        const redisSessionTokens = redisTokens ? JSON.parse(redisTokens) : {}
+        delete redisSessionTokens[ sessionToken.id]
         return this.redis.setAsync(uid, JSON.stringify(redisSessionTokens))
       })
   }

test/remote/db_tests.js

@@ -201,7 +201,7 @@ describe('remote db', function() {
           assert.equal(redisSetSpy.lastCall.args[0], account.uid)
 
           const redisSetArgs = JSON.parse(redisSetSpy.lastCall.args[1])
-          const token = redisSetArgs[0]
+          const token = redisSetArgs[tokenId]
           assert.equal(token.tokenId, tokenId)
           assert.equal(token.uid, account.uid)
           assert.equal(token.uaBrowser, 'Firefox')
@@ -239,20 +239,23 @@ describe('remote db', function() {
           return sessionToken
         })
         .then(function(sessionToken) {
-          const mockTokens = JSON.stringify([{
-            uid: sessionToken.uid,
-            id: 'idToNotDelete'
-          }, {
-            uid: sessionToken.uid,
-            id: sessionToken.id
-          }])
+          const mockTokens = JSON.stringify({
+            idToNotDelete: {
+              uid: sessionToken.uid,
+              id: 'idToNotDelete'
+            },
+            [sessionToken.id]: {
+              uid: sessionToken.uid,
+              id: sessionToken.id
+            }
+          })
           redisGetSpy.returns(P.resolve(mockTokens))
           return db.deleteSessionToken(sessionToken)
         })
         .then(function() {
           const redisSetArgs = JSON.parse(redisSetSpy.lastCall.args[1])
-          assert.equal(redisSetArgs.length, 1)
-          assert.equal(redisSetArgs[0].id, 'idToNotDelete')
+          assert.equal(Object.keys(redisSetArgs).length, 1)
+          assert.ok(redisSetArgs.idToNotDelete)
 
           return db.sessionToken(tokenId)
           .then(function(sessionToken) {
@@ -383,7 +386,8 @@ describe('remote db', function() {
               })
           })
           .then(results => {
-            redisGetSpy.returns(P.resolve(JSON.stringify(results[1])))
+            const tokenToReturn = results[1][sessionToken.tokenId]
+            redisGetSpy.returns(P.resolve(JSON.stringify({[sessionToken.tokenId]: tokenToReturn})))
 
             // Create another session token
             return db.createSessionToken(sessionToken, 'Mozilla/5.0 (Android 7.1.2; Mobile; rv:56.0) Gecko/56.0 Firefox/56.0')