Refactor into class

src/index.js

@@ -3,38 +3,53 @@ const NodeCache   = require('node-cache');
 const querystring = require('querystring');
 const pkg         = require('../package.json');
 
-const cache = new NodeCache();
+class Onionoo {
 
-const baseUrl   = 'https://onionoo.torproject.org';
+  // Constructor returns a new object so instance properties are private
-const endpoints = [
+  constructor(options = {}) {
+
+    // Set default options
+    this.options = Object.assign({}, {
+      cache:      new NodeCache(),
+      baseUrl:    'https://onionoo.torproject.org',
+      endpoints:  [
         'summary',
         'details',
         'bandwidth',
         'weights',
         'clients',
         'uptime'
-];
+      ]
+    }, options);
+
+    // Return object containing endpoint methods
+    return this.options.endpoints.reduce((onionoo, endpoint) => {
+      onionoo[endpoint] = this.createEndpointMethod(endpoint);
+
+      return onionoo;
+    }, {});
+  }
 
-// Returns cache max age from response headers
+  // Returns cache max age from response headers
-function checkResponseMaxAge(response) {
+  checkResponseMaxAge(response) {
     const cacheControl = response.headers['cache-control'];
     const maxAgeRegex = /max-age=(\d+)/;
     const maxAge = cacheControl && cacheControl.match(maxAgeRegex);
     return maxAge && maxAge[1];
-}
+  }
 
-// Returns a function to make requests to a given endpoint
+  // Returns a function to make requests to a given endpoint
-function createEndpointMethod(endpoint) {
+  createEndpointMethod(endpoint) {
     return args => new Promise((resolve, reject) => {
 
       // Build query string (don't encode ':' for search filters)
       const qs = querystring.encode(args).replace(/%3A/g, ':');
 
       // Build url
-    const url = `${baseUrl}/${endpoint}?${qs}`;
+      const url = `${this.options.baseUrl}/${endpoint}?${qs}`;
 
       // Check for url in cache
-    const cachedResult = cache.get(url);
+      const cachedResult = this.options.cache.get(url);
       if(cachedResult) {
         resolve(cachedResult);
       } else {
@@ -48,9 +63,9 @@ function createEndpointMethod(endpoint) {
           .then(response => {
 
             // Cache response
-          const ttl = checkResponseMaxAge(response);
+            const ttl = this.checkResponseMaxAge(response);
             if(ttl) {
-            cache.set(url, response.body, ttl);
+              this.options.cache.set(url, response.body, ttl);
             }
 
             // Resolve response
@@ -58,11 +73,7 @@ function createEndpointMethod(endpoint) {
           }));
       }
     });
+  }
 }
 
-// Return object containing endpoint methods
+module.exports = Onionoo;
-module.exports = endpoints.reduce((onionoo, endpoint) => {
-  onionoo[endpoint] = createEndpointMethod(endpoint);
-
-  return onionoo;
-}, {});