Added API Caching functionality

.gitignore

@@ -5,5 +5,6 @@ services/auth/secrets.json
 .directory
 
 radata/
+radata-*.tmp
 *.cert
 *.key

package.json

@@ -5,7 +5,7 @@
   "main": "src/server.js",
   "scripts": {
     "start": "node --experimental-modules src/server.js",
-    "dev": "node main.js -h 0.0.0.0",
+    "dev": "node --max-old-space-size=4096 main.js -h 0.0.0.0",
     "dev:watch": "nodemon main.js -- -h 0.0.0.0",
     "test": "jest --no-cache",
     "test:watch": "jest --no-cache --watch",

services/auth/secrets.json

@@ -1,5 +1,20 @@
 {
   "1582813836485": "b8328f50-596d-11ea-b251-cf923e62abf5",
   "1582815195785": "e2674790-5970-11ea-ba5d-4b7fda6488de",
-  "1582820933939": "3e9c1830-597e-11ea-acaa-2b96f5467d08"
+  "1582820933939": "3e9c1830-597e-11ea-acaa-2b96f5467d08",
+  "1582670203354": "4c2e13a0-581f-11ea-ad3d-a73b4b4c0361",
+  "1583339145556": "cccda140-5e34-11ea-8c4e-17a1f5fd1235",
+  "1583584195969": "5a3b3f10-606f-11ea-8523-9d59c298ff41",
+  "1583584284436": "8ef63d40-606f-11ea-ba0f-e74d20a4ef9a",
+  "1583584328860": "a970cdc0-606f-11ea-ba0f-e74d20a4ef9a",
+  "1583584658911": "6e2a96f0-6070-11ea-ba0f-e74d20a4ef9a",
+  "1583585004260": "3c02aa40-6071-11ea-987e-bd3595c9104b",
+  "1583585179728": "a498f500-6071-11ea-a5f5-1f051c0be7de",
+  "1583585675201": "cbec2310-6072-11ea-a5f5-1f051c0be7de",
+  "1583585744767": "f56310f0-6072-11ea-a5f5-1f051c0be7de",
+  "1583585838554": "2d49d3a0-6073-11ea-b4d0-f9a792ba6160",
+  "1583586016626": "976d7520-6073-11ea-a6b4-4380ee6b86a1",
+  "1583588647390": "b77c2fe0-6079-11ea-a0aa-8368c2d33cfe",
+  "1583590307894": "9538fd60-607d-11ea-92cb-ed88e8db1271",
+  "1583590742693": "98623460-607e-11ea-bf6c-611b3b0363dc"
 }

src/routes.js

@@ -212,6 +212,7 @@ module.exports = async (
 
   app.use((req, res, next) => {
     const deviceId = req.headers["x-shockwallet-device-id"];
+    console.log("Decrypting route...")
     try {
       if (nonEncryptedRoutes.includes(req.path)) {
         return next();

src/server.js

@@ -9,6 +9,7 @@ const server = program => {
   const Https = require('https')
   const Http = require('http')
   const Express = require('express')
+  const Crypto = require('crypto')
   const LightningServices = require('../utils/lightningServices')
   const Encryption = require('../utils/encryptionStore')
   const app = Express()
@@ -41,6 +42,25 @@ const server = program => {
 
   logger.info('Mainnet Mode:', !!program.mainnet)
 
+  const stringifyData = data => {
+    if (typeof data === 'object') {
+      const stringifiedData = JSON.stringify(data)
+      return stringifiedData
+    }
+
+    if (data.toString) {
+      return data.toString()
+    }
+
+    return data
+  }
+
+  const hashData = data => {
+    return Crypto.createHash('SHA256')
+      .update(Buffer.from(stringifyData(data)))
+      .digest('hex')
+  }
+
   const modifyResponseBody = (req, res, next) => {
     const deviceId = req.headers['x-shockwallet-device-id']
     const oldSend = res.send
@@ -50,18 +70,35 @@ const server = program => {
         if (args[0] && args[0].encryptedData && args[0].encryptionKey) {
           logger.warn('Response loop detected!')
           oldSend.apply(res, args)
-        } else {
-          // arguments[0] (or `data`) contains the response body
-          const authorized = Encryption.isAuthorizedDevice({ deviceId })
-          const encryptedMessage = authorized
-            ? Encryption.encryptMessage({
-                message: args[0],
-                deviceId
-              })
-            : args[0]
-          args[0] = JSON.stringify(encryptedMessage)
-          oldSend.apply(res, args)
+          return
         }
+
+        const dataHash = hashData(args[0])
+        res.set('ETag', dataHash)
+
+        console.log('ETag:', req.headers.etag)
+        console.log('Data Hash:', dataHash)
+        if (req.headers.etag === dataHash) {
+          console.log('Same Hash Detected!')
+          args[0] = null
+          res.status(304)
+          oldSend.apply(res, args)
+          return
+        }
+
+        // arguments[0] (or `data`) contains the response body
+        const authorized = Encryption.isAuthorizedDevice({ deviceId })
+        const encryptedMessage = authorized
+          ? Encryption.encryptMessage({
+              message: args[0],
+              deviceId,
+              metadata: {
+                hash: dataHash
+              }
+            })
+          : args[0]
+        args[0] = JSON.stringify(encryptedMessage)
+        oldSend.apply(res, args)
       }
     }
     next()

utils/encryptionStore.js

@@ -49,7 +49,7 @@ const Encryption = {
 
     return encryptedData.toString()
   },
-  encryptMessage: ({ deviceId, message }) => {
+  encryptMessage: ({ deviceId, message, metadata }) => {
     const parsedMessage =
       typeof message === 'object' ? JSON.stringify(message) : message
     const data = Buffer.from(parsedMessage)
@@ -66,7 +66,7 @@ const Encryption = {
       Buffer.from(cipher.final())
     ])
     const encryptedData = encryptedBuffer.toString('base64')
-    return { encryptedData, encryptedKey, iv: iv.toString('hex') }
+    return { encryptedData, encryptedKey, iv: iv.toString('hex'), metadata }
   },
   decryptMessage: ({ message, key, iv }) => {
     const data = Buffer.from(message, 'base64')