Add redis and endpoint that uses it

Author: shea-ymc

Gruntfile.js

@@ -93,7 +93,6 @@ module.exports = function(grunt) {
                 ],
             },
             src: [
-                'Gruntfile.js',
                 'src/**/*.js',
                 'test/**/*.js',
                 'config/**/*.js',

config/env/development.js.example

@@ -1,3 +1,4 @@
 module.exports = {
     env: 'development',
+    redis_db: 1,
 };

config/env/production.js.example

@@ -2,4 +2,5 @@ module.exports = {
     env: 'production',
     ip: process.env.IP || '0.0.0.0',
     port: process.env.PORT || 8080,
+    redis_db: 3,
 };

config/env/test.js.example

@@ -1,3 +1,4 @@
 module.exports = {
     env: 'test',
+    redis_db: 2,
 };

package.json

@@ -29,12 +29,15 @@
     "should": "^4.0.4"
   },
   "dependencies": {
+    "async": "^0.9.0",
     "body-parser": "^1.8.2",
     "express": "^4.9.3",
     "grunt-env": "^0.4.1",
     "grunt-express-server": "^0.4.19",
+    "hiredis": "^0.1.17",
     "lodash": "^2.4.1",
     "node-strict": "^1.0.0",
+    "redis": "^0.12.1",
     "request": "^2.44.0",
     "winston": "^0.8.0"
   }

src/controllers/request-counter.js

@@ -0,0 +1,20 @@
+module.exports = RequestCounter;
+
+var redis = require('../resources/redis'),
+    ApiResponder = require('../resources/api-responder');
+
+var NUM_REQS_KEY = 'NUM_REQS';
+
+RequestCounter.get = function(req, res) {
+    redis.incr(NUM_REQS_KEY, function(err, newVal) {
+        var apiResponder = new ApiResponder(res);
+        if (err) {
+            apiResponder.sendError(err);
+        } else {
+            var data = { num_reqs: newVal };
+            apiResponder.sendSuccess(data);
+        }
+    });
+};
+
+function RequestCounter() {}

src/resources/api-responder.js

@@ -0,0 +1,15 @@
+module.exports = ApiResponder;
+
+var _ = require('lodash');
+
+function ApiResponder(res) {
+    this.res = res;
+    this.sendSuccess = function(data) {
+        this.res.status(200).send(data);
+    };
+
+    this.sendError = function(err) {
+        this.res.status(500).send(err);
+    };
+}
+

src/resources/redis.js

@@ -0,0 +1,29 @@
+var redis = require('redis');
+var config = require('../../config/config');
+
+var client = client || redis.createClient(),
+    initialized = initialized || false,
+    initializing = initializing || false;
+
+if (shouldInitialize()) {
+    signalInitStart();
+    client.select(config.redis_db,
+        signalInitEnd);
+}
+
+function shouldInitialize() {
+    return !initialized && !initializing;
+}
+
+function signalInitStart() {
+    initializing = true;
+}
+
+function signalInitEnd(err) {
+    initializing = false;
+    initialized = !err;
+    if (err) throw err;
+}
+
+
+module.exports = client;

src/routes.js

@@ -1,4 +1,8 @@
+var requestCounterController = require('./controllers/request-counter');
+
 module.exports = function(app) {
+    app.get('/requestcounter', requestCounterController.get);
+
     app.get('/', function(req, res) {
         res
         .status(200)

test/request-counter.js

@@ -0,0 +1,37 @@
+var should = require('should'),
+    request = require('request'),
+    async = require('async');
+
+var config = require('../config/config');
+
+var redis = require('../src/resources/redis');
+
+before(function(done) {
+    redis.flushdb(done);
+});
+
+after(function(done) {
+    redis.flushdb(done);
+});
+
+it('should count the number of requests sent', function(done) {
+    var url = 'http://' + config.ip + ':' + config.port + '/requestcounter';
+
+    async.times(5, function(n, next) {
+        request(url, function(err, resp, body) {
+            if (err) next(err);
+
+            try {
+                body = JSON.parse(body);
+                var found = parseInt(body.num_reqs),
+                    expected = n + 1;
+                found.should.equal(expected);
+                next();
+            } catch(e) {
+                next(e);
+            }
+        });
+    },
+    done);
+});
+