Created refactored route-utils2.js library

src/routes/v3/full-node/blockchain2.js

@@ -7,14 +7,16 @@
 const express = require("express")
 const router = express.Router()
 
+const axios = require("axios")
+const wlogger = require("../../../util/winston-logging")
+
+const RouteUtils = require("../route-utils2")
+const routeUtils = new RouteUtils()
+
 // Used to convert error messages to strings, to safely pass to users.
 const util = require("util")
 util.inspect.defaultOptions = { depth: 1 }
 
-const axios = require("axios")
-const routeUtils = require("../route-utils")
-const wlogger = require("../../../util/winston-logging")
-
 const BCHJS = require("@chris.troutner/bch-js")
 const bchjs = new BCHJS()
 
@@ -26,6 +28,7 @@ class Blockchain {
 
     this.bchjs = bchjs
     this.axios = axios
+    this.routeUtils = routeUtils
 
     this.router = router
     this.router.get("/", this.root)
@@ -40,7 +43,7 @@ class Blockchain {
   // DRY error handler.
   errorHandler(err, res) {
     // Attempt to decode the error message.
-    const { msg, status } = routeUtils.decodeError(err)
+    const { msg, status } = this.routeUtils.decodeError(err)
     if (msg) {
       res.status(status)
       return res.json({ error: msg })
@@ -65,7 +68,7 @@ class Blockchain {
   async getBestBlockHash(req, res, next) {
     try {
       // Axios options
-      const options = routeUtils.getAxiosOptions()
+      const options = this.routeUtils.getAxiosOptions()
       options.data.id = "getbestblockhash"
       options.data.method = "getbestblockhash"
       options.data.params = []
@@ -110,7 +113,7 @@ class Blockchain {
   async getBlockchainInfo(req, res, next) {
     try {
       // Axios options
-      const options = routeUtils.getAxiosOptions()
+      const options = this.routeUtils.getAxiosOptions()
       options.data.id = "getblockchaininfo"
       options.data.method = "getblockchaininfo"
       options.data.params = []

src/routes/v3/route-utils2.js

@@ -0,0 +1,163 @@
+/*
+  A private library of utility functions used by several different routes.
+*/
+
+"use strict"
+
+const axios = require("axios")
+const wlogger = require("../../util/winston-logging")
+
+const util = require("util")
+util.inspect.defaultOptions = { depth: 1 }
+
+const BCHJS = require("@chris.troutner/bch-js")
+const bchjs = new BCHJS()
+
+let _this
+
+class RouteUtils {
+  constructor() {
+    _this = this
+
+    this.bchjs = bchjs
+    this.axios = axios
+  }
+
+  // This function expects the Request Express.js object and an array as input.
+  // The array is then validated against freemium and pro-tier rate limiting
+  // requirements. A boolean is returned to indicate if the array size if valid
+  // or not.
+  validateArraySize(req, array) {
+    const FREEMIUM_INPUT_SIZE = 20
+    const PRO_INPUT_SIZE = 20
+
+    if (req.locals && req.locals.proLimit) {
+      if (array.length <= PRO_INPUT_SIZE) return true
+    } else if (array.length <= FREEMIUM_INPUT_SIZE) {
+      return true
+    }
+
+    return false
+  }
+
+  // Axios options used when calling axios.post() to talk with a full node.
+  getAxiosOptions() {
+    return {
+      method: "post",
+      baseURL: process.env.RPC_BASEURL,
+      timeout: 15000,
+      auth: {
+        username: process.env.RPC_USERNAME,
+        password: process.env.RPC_PASSWORD
+      },
+      data: {
+        jsonrpc: "1.0"
+      }
+    }
+  }
+
+  // Returns true if user-provided cash address matches the correct network,
+  // mainnet or testnet. If NETWORK env var is not defined, it returns false.
+  // This prevent a common user-error issue that is easy to make: passing a
+  // testnet address into rest.bitcoin.com or passing a mainnet address into
+  // trest.bitcoin.com.
+  validateNetwork(addr) {
+    try {
+      const network = process.env.NETWORK
+
+      // Return false if NETWORK is not defined.
+      if (!network || network === "") {
+        console.log(`Warning: NETWORK environment variable is not defined!`)
+        return false
+      }
+
+      // Convert the user-provided address to a cashaddress, for easy detection
+      // of the intended network.
+      const cashAddr = this.bchjs.Address.toCashAddress(addr)
+
+      // Return true if the network and address both match testnet
+      const addrIsTest = this.bchjs.Address.isTestnetAddress(cashAddr)
+      if (network === "testnet" && addrIsTest) return true
+
+      // Return true if the network and address both match mainnet
+      const addrIsMain = this.bchjs.Address.isMainnetAddress(cashAddr)
+      if (network === "mainnet" && addrIsMain) return true
+
+      return false
+    } catch (err) {
+      logger.error(`Error in validateNetwork()`)
+      return false
+    }
+  }
+
+  // Error messages returned by a full node can be burried pretty deep inside the
+  // error object returned by Axios. This function attempts to extract and interpret
+  // error messages.
+  // Returns an object. If successful, obj.msg is a string.
+  // If there is a failure, obj.msg is false.
+  decodeError(err) {
+    try {
+      // Attempt to extract the full node error message.
+      if (
+        err.response &&
+        err.response.data &&
+        err.response.data.error &&
+        err.response.data.error.message
+      )
+        return { msg: err.response.data.error.message, status: 400 }
+
+      // Attempt to extract the Insight error message
+      if (err.response && err.response.data)
+        return { msg: err.response.data, status: err.response.status }
+
+      // console.log(`err.message: ${err.message}`)
+      // console.log(`err: `, err)
+
+      // Attempt to detect a network connection error.
+      if (err.message && err.message.indexOf("ENOTFOUND") > -1) {
+        return {
+          msg:
+            "Network error: Could not communicate with full node or other external service.",
+          status: 503
+        }
+      }
+
+      // Different kind of network error
+      if (err.message && err.message.indexOf("ENETUNREACH") > -1) {
+        return {
+          msg:
+            "Network error: Could not communicate with full node or other external service.",
+          status: 503
+        }
+      }
+
+      // Different kind of network error
+      if (err.message && err.message.indexOf("EAI_AGAIN") > -1) {
+        return {
+          msg:
+            "Network error: Could not communicate with full node or other external service.",
+          status: 503
+        }
+      }
+
+      // Axios timeout (aborted) error, or service is down (connection refused).
+      if (
+        err.code &&
+        (err.code === "ECONNABORTED" || err.code === "ECONNREFUSED")
+      ) {
+        return {
+          msg:
+            "Network error: Could not communicate with full node or other external service.",
+          status: 503
+        }
+      }
+
+      return { msg: false, status: 500 }
+    } catch (err) {
+      wlogger.error(`unhandled error in route-utils.js/decodeError(): `, err)
+      return { msg: false, status: 500 }
+    }
+  }
+}
+
+module.exports = RouteUtils

test/v3/blockchain2.js

@@ -28,7 +28,7 @@ const mockData = require("./mocks/blockchain-mock")
 
 let originalEnvVars // Used during transition from integration to unit tests.
 
-describe("#BlockchainRouter", () => {
+describe("#BlockchainRouter2", () => {
   let req, res
   let sandbox