Beginnings of an API

api.js

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+var request = require('request');
+var _ = require('underscore');
+
+
+var DEFAULT_ERROR = 'There was a problem accessing this data.';
+var DEFAULT_QUERY = {
+  page: 1
+};
+
+
+// Core API function
+// Used as middleware to intercept XHR requests
+function api (method) {
+  return function (req, res, next) {
+    if (!req.xhr)
+      return next();
+
+    res.contentType('application/json');
+
+    if (!_.isFunction(method))
+      method = api[method];
+
+    if (!_.isFunction(method))
+      return res.json({error: 500, message: DEFAULT_ERROR});
+
+    // Build query from various inputs
+    var query = _.extend(
+      DEFAULT_QUERY,
+      req.query||{},
+      req.body||{},
+      req.params||{}
+    );
+
+    method(query, function(err, data) {
+      if (!_.isObject(data))
+        data = {};
+
+      if (err)
+        data.error = err;
+
+      return res.json(data);
+    });
+  }
+}
+
+// Wrapper for API methods
+// Normalises input and output
+function apiMethod (method) {
+  return function (query, callback) {
+    if (_.isFunction(query) && !callback) {
+      callback = query;
+      query = {};
+    }
+
+    // Assume any non-object query is being passed in as an ID
+    if (!_.isObject(query))
+      query = {id: query};
+
+    query = _.defaults(query, DEFAULT_QUERY);
+
+    method(query, function(err, data) {
+      if (!err)
+        return callback(null, data);
+
+      if (!data || _.isString(data))
+        data = {message: data || DEFAULT_ERROR};
+
+      callback(err, data);
+    });
+  }
+}
+
+// Load data from remote endpoint
+function remote (method, path, callback) {
+  // TODO - put this in settings somewhere
+  var origin = 'http://openbadger-csol.mofostaging.net';
+
+  if (!request[method])
+    return callback(500, 'Unknown method');
+
+  // TODO - need to add ability to pass data through
+  // TODO - might want to cache this at some point
+  request[method](origin + path, function(err, response, body) {
+    if (err)
+      return callback(500, err);
+
+    if (response.statusCode !== 200)
+      return callback(500, 'Upstream error');
+
+    try {
+      var data = JSON.parse(body);
+    } catch (e) {
+      return callback(500, e.message);
+    }
+
+    if (data.status !== 'ok')
+      return callback(500, data.reason);
+
+    callback(null, data);
+  });
+}
+
+// Make sure badges returned from remote API
+// contain all the information we need
+function normalizeBadge (badge, id) {
+  if (!badge.id)
+    badge.id = id;
+
+  if (!badge.url)
+    badge.url = '/badges/' + badge.id;
+
+  return badge;
+}
+
+api.getBadges = apiMethod(function getBadges (query, callback) {
+  var pageSize = 12,
+      page = parseInt(query.page, 10),
+      start = (page - 1) * pageSize,
+      end = start + pageSize;
+
+  if (isNaN(page) || page < 1)
+    return callback(400, 'Invalid page number');
+
+  remote('get', '/v1/badges', function(err, data) {
+    if (err)
+      return callback(err, data);
+
+    var badges = _.map(data.badges, normalizeBadge);
+    var pages = Math.ceil(badges.length / pageSize);
+
+    if (page > pages)
+      return callback(404, {
+        message: 'Page not found',
+        page: page,
+        pages: pages
+      });
+
+    callback(null, {
+      page: page,
+      pages: pages,
+      items: badges.slice(start, end)
+    });
+  });
+});
+
+api.getBadge = apiMethod(function getBadge (query, callback) {
+  var id = query.id;
+
+  if (!id)
+    return callback(400, 'Invalid badge key');
+
+  remote('get', '/v1/badges', function(err, data) {
+    if (err)
+      return callback(err, data);
+
+    var badge = data.badges[id];
+
+    if (!badge)
+      return callback(404, 'Badge not found');
+
+    normalizeBadge(badge, id);
+
+    callback(null, {
+      badge: badge
+    });
+  });
+});
+
+module.exports = api;