Refactor into class

src/index.js

@@ -3,66 +3,77 @@ 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';
-const endpoints = [
-  'summary',
-  'details',
-  'bandwidth',
-  'weights',
-  'clients',
-  'uptime'
-];
+  // Constructor returns a new object so instance properties are private
+  constructor(options = {}) {
 
-// Returns cache max age from response headers
-function checkResponseMaxAge(response) {
-  const cacheControl = response.headers['cache-control'];
-  const maxAgeRegex = /max-age=(\d+)/;
-  const maxAge = cacheControl && cacheControl.match(maxAgeRegex);
-  return maxAge && maxAge[1];
-}
+    // Set default options
+    this.options = Object.assign({}, {
+      cache:      new NodeCache(),
+      baseUrl:    'https://onionoo.torproject.org',
+      endpoints:  [
+        'summary',
+        'details',
+        'bandwidth',
+        'weights',
+        'clients',
+        'uptime'
+      ]
+    }, options);
 
-// Returns a function to make requests to a given endpoint
-function createEndpointMethod(endpoint) {
-  return args => new Promise((resolve, reject) => {
+    // Return object containing endpoint methods
+    return this.options.endpoints.reduce((onionoo, endpoint) => {
+      onionoo[endpoint] = this.createEndpointMethod(endpoint);
 
-    // Build query string (don't encode ':' for search filters)
-    const qs = querystring.encode(args).replace(/%3A/g, ':');
+      return onionoo;
+    }, {});
+  }
 
-    // Build url
-    const url = `${baseUrl}/${endpoint}?${qs}`;
+  // Returns cache max age from response headers
+  checkResponseMaxAge(response) {
+    const cacheControl = response.headers['cache-control'];
+    const maxAgeRegex = /max-age=(\d+)/;
+    const maxAge = cacheControl && cacheControl.match(maxAgeRegex);
+    return maxAge && maxAge[1];
+  }
 
-    // Check for url in cache
-    const cachedResult = cache.get(url);
-    if(cachedResult) {
-      resolve(cachedResult);
-    } else {
+  // Returns a function to make requests to a given endpoint
+  createEndpointMethod(endpoint) {
+    return args => new Promise((resolve, reject) => {
 
-      // Make request
-      const options = {
-        json: true,
-        'user-agent': `onionoo-node-client v${pkg.version} (${pkg.homepage})`
-      };
-      resolve(got(url, options)
-        .then(response => {
+      // Build query string (don't encode ':' for search filters)
+      const qs = querystring.encode(args).replace(/%3A/g, ':');
 
-          // Cache response
-          const ttl = checkResponseMaxAge(response);
-          if(ttl) {
-            cache.set(url, response.body, ttl);
-          }
+      // Build url
+      const url = `${this.options.baseUrl}/${endpoint}?${qs}`;
 
-          // Resolve response
-          return response.body;
-        }));
-    }
-  });
-}
+      // Check for url in cache
+      const cachedResult = this.options.cache.get(url);
+      if(cachedResult) {
+        resolve(cachedResult);
+      } else {
+
+        // Make request
+        const options = {
+          json: true,
+          'user-agent': `onionoo-node-client v${pkg.version} (${pkg.homepage})`
+        };
+        resolve(got(url, options)
+          .then(response => {
 
-// Return object containing endpoint methods
-module.exports = endpoints.reduce((onionoo, endpoint) => {
-  onionoo[endpoint] = createEndpointMethod(endpoint);
+            // Cache response
+            const ttl = this.checkResponseMaxAge(response);
+            if(ttl) {
+              this.options.cache.set(url, response.body, ttl);
+            }
+
+            // Resolve response
+            return response.body;
+          }));
+      }
+    });
+  }
+}
 
-  return onionoo;
-}, {});
+module.exports = Onionoo;