feat: Full featured browser capabilities

Complete with a full jQuery example.
nodeshift · Dec 20, 2016 · 427c155 · 427c155
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diff --git a/examples/jquery/.eslintrc.json b/examples/jquery/.eslintrc.json
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+{
+  "extends": "semistandard"
+}
diff --git a/examples/jquery/.gitignore b/examples/jquery/.gitignore
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+node_modules
diff --git a/examples/jquery/README.md b/examples/jquery/README.md
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+# JQuery Example
+
+This example exposes a simple service at the route `http://localhost:3000/flakeyService`. As the service receives requests, it gets slower and slower. Once it takes more than 1 second to respond, the service just returns a `423 (Locked)` error.
+
+Start the server.
+
+```sh
+$ npm start
+```
+
+Browse to `http://localhost:3000` and click the button to see the service in action.
diff --git a/examples/jquery/app.js b/examples/jquery/app.js
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+'use strict';
+/* global $ circuitBreaker */
+
+(function appInitialization () {
+  $(() => {
+    $('#flakey').click(handleClick('/flakeyService', '#flakeyResponse'));
+    $('.clear').click(function () { $(this).siblings('p').remove(); });
+  });
+
+  const circuitBreakerOptions = {
+    timeout: 500,
+    maxFailures: 2,
+    resetTimeout: 5000,
+    Promise: Promise
+  };
+
+  function handleClick (route, element) {
+    const circuit = circuitBreaker((route, element) => {
+      circuit.fallback(() => ({ body: `${route} unavailable right now. Try later.` }));
+
+      // Return a promise to the circuit
+      return new Promise((resolve, reject) => {
+        $.get(route)
+          .done((data) => resolve(data))
+          .fail((err) => {
+            reject(err);
+            console.error(err);
+          });
+      });
+    }, circuitBreakerOptions);
+
+    circuit.on('success',
+      (data) => $(element).append(makeNode(`SUCCESS: ${JSON.stringify(data)}`)));
+
+    circuit.on('timeout',
+      () => $(element).append(
+        makeNode(`TIMEOUT: ${route} is taking too long to respond.`)));
+
+    circuit.on('reject',
+      () => $(element).append(
+        makeNode(`REJECTED: The breaker for ${route} is open. Failing fast.`)));
+
+    circuit.on('open',
+      () => $(element).append(
+        makeNode(`OPEN: The breaker for ${route} just opened.`)));
+
+    circuit.on('halfOpen',
+      () => $(element).append(
+        makeNode(`HALF_OPEN: The breaker for ${route} is half open.`)));
+
+    circuit.on('close',
+      () => $(element).append(
+        makeNode(`CLOSE: The breaker for ${route} has closed. Service OK.`)));
+
+    circuit.on('fallback',
+      (data) => $(element).append(
+        makeNode(`FALLBACK: ${JSON.stringify(data)}`)));
+
+    return () => circuit.fire(route, element).catch((e) => console.error(e));
+  }
+
+  function makeNode (body) {
+    const response = document.createElement('p');
+    $(response).addClass(body.substring(0, body.indexOf(':')).toLowerCase());
+    response.append(body);
+    return response;
+  }
+})();
diff --git a/examples/jquery/index.html b/examples/jquery/index.html
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+<html>
+<head>
+  <title>Opossum Circuit Breaker Example</title>
+  <script type='text/javascript' src="/jquery.js"></script>
+  <script type='text/javascript' src="/opossum.js"></script>
+  <script type='text/javascript' src="/app.js"></script>
+  <style>
+    body {
+      font-family: Arial, Helvetica, sans-serif;
+      margin: 1em;
+    }
+    button {
+      padding: 1ex 1em;
+      margin-right: 1em;
+      font-size: larger;
+    }
+    .row {
+      padding: 1em;
+      width: 100%
+    }
+    h2 {
+      border-bottom: 1px dotted #999;
+    }
+    .clear {
+      cursor: pointer;
+      color: #3336ff;
+    }
+    .success {
+      color: darkgreen
+    }
+    .open {
+      color: red
+    }
+    .fallback {
+      color: darkblue
+    }
+    .rejected {
+      color: darkorange
+    }
+    .close {
+      color: green
+    }
+    .timeout {
+      color: darksalmon
+    }
+  </style>
+</head>
+<body>
+  <div>
+    <h1>Opossum Circuit Breaker Example</h1>
+
+    <p>
+      When you click the button here, this simple app calls a flakey web service that takes longer and longer to respond. The app's circuit breaker is configured to timeout after 500ms and execute a fallback command. Every 20 seconds, the flakey service is reset and the pattern is repeated. This should allow you to see all of the various events that occur when using a circuit breaker.
+    </p>
+    <p>
+      The <a href="/app.js">source code</a> for the application is relatively simple, and uses some basic jQuery capabilities to make the ajax calls and update the DOM accordingly.
+    </p>
+    <div class="row">
+      <button type="button" id="flakey">
+        Flakey Service
+      </button>
+    </div>
+
+    <div class="row" id="flakeyResponse">
+      <h2>FLAKEY RESPONSES</h2>
+      <span class="clear">Click to clear</span>
+    </div>
+  </div>
+</body>
+</html>
diff --git a/examples/jquery/index.js b/examples/jquery/index.js
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+'use strict';
+
+const Hapi = require('hapi');
+const Boom = require('boom');
+const path = require('path');
+const util = require('util');
+
+const server = new Hapi.Server();
+
+server.connection({
+  host: 'localhost',
+  port: 3000
+});
+
+// static file serving
+server.register(require('inert', (err) => possibleError(err)));
+
+[ ['/', path.join(__dirname, 'index.html')],
+  ['/app.js', path.join(__dirname, 'app.js')],
+  ['/jquery.js', path.join(__dirname, 'node_modules', 'jquery', 'dist', 'jquery.js')],
+  ['/opossum.js', path.join(__dirname, '..', '..', 'dist', 'opossum.js')]
+].map((entry) => {
+  server.route({
+    method: 'GET',
+    path: entry[0],
+    handler: {
+      file: {
+        path: entry[1],
+        confine: false
+      }
+    }
+  });
+});
+
+const baseline = 20;
+let delay = baseline;
+server.route({
+  method: 'GET',
+  path: '/flakeyService',
+  handler: function flakeyService (request, reply) {
+    console.log('Flakey service delay', delay);
+    // if we're really slowing down, just reply with an error
+    if (delay > 1000) {
+      console.log('Long delay encountered, returning Error 423 (Locked)');
+      return reply(
+        Boom.locked(util.format({ body: 'Flakey service is flakey' })));
+    }
+    const response = reply({
+      body: 'Flakey service response',
+      delay
+    }, delay).hold();
+    setTimeout(() => {
+      console.log('Replying with flakey response after delay of', delay);
+      delay = delay * 2;
+      response.send();
+    }, delay);
+  }
+});
+
+// reset the delay every 10 seconds
+setInterval(() => {
+  delay = baseline;
+  console.log('Resetting flakey service delay to', delay);
+}, 20000);
+
+server.start((err) => {
+  possibleError(err);
+  console.log(`Server: ${server.info.uri}`);
+  console.log('Endpoints:');
+  server.table().map((entry) => {
+    entry.table.map((route) => {
+      console.log(`${route.method} ${route.path}`);
+    });
+  });
+});
+
+process.on('uncaughtException', (e) => {
+  process._rawDebug(`Caught exception ${e}`);
+});
+
+function possibleError (err) {
+  if (err) throw err;
+}
+
diff --git a/examples/jquery/package.json b/examples/jquery/package.json
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+{
+  "name": "opossum-browser-example",
+  "version": "0.0.1",
+  "main": "index.js",
+  "license": "Apache-2.0",
+  "scripts": {
+    "lint": "eslint test/*.js index.js app.js",
+    "start": "node ."
+  },
+  "repository": {
+    "type": "git",
+    "url": "git://github.com/bucharest-gold/opossum.git"
+  },
+  "devDependencies": {
+    "eslint": "~3.8.1",
+    "eslint-config-semistandard": "~7.0.0",
+    "eslint-config-standard": "~6.2.0",
+    "eslint-plugin-promise": "~3.3.0",
+    "eslint-plugin-react": "~6.4.1",
+    "eslint-plugin-standard": "~2.0.1"
+  },
+  "description": "Simple example with opossum and browser.",
+  "dependencies": {
+    "angular": "^1.6.0",
+    "angular-route": "^1.6.0",
+    "boom": "~4.2.0",
+    "bootstrap": "~3.3.7",
+    "hapi": "~16.0.1",
+    "inert": "~4.0.3",
+    "jquery": "~3.1.1"
+  },
+  "bugs": {
+    "url": "https://github.com/bucharest-gold/opossum/issues"
+  },
+  "homepage": "https://github.com/bucharest-gold/opossum#readme",
+  "author": ""
+}