add a health endpoint

Signed-off-by: Andreas Bräu <ab@andi95.de>

routes/health.js

@@ -0,0 +1,49 @@
+var app = require('../app');
+
+var mongoose = require('mongoose');
+
+const Errors = {
+    DBERROR: 'DBERROR'
+}
+
+exports.gethealth = function(req, res) {
+    const mongoose_state = mongoose.connection.readyState
+    var errors = collectErrors();
+    if (errors.length == 0) {
+        res.status(200).json({
+            status: "OK",
+            mongoose: mongoose_state
+        });
+    } else {
+        return res.status(500).json({
+            status: "Not OK",
+            mongoose: mongoose_state,
+            errors: errors
+        });
+    }
+
+    function collectErrors() {
+        var errors = [];
+        switch (mongoose_state) {
+            case 0:
+                errors.push({
+                    error: Errors.DBERROR,
+                    message: "mongodb disconnected"
+                });
+                break;
+            case 2:
+                errors.push({
+                    error: Errors.DBERROR,
+                    message: "mongodb connecting"
+                });
+                break;
+            case 3:
+                errors.push({
+                    error: Errors.DBERROR,
+                    message: "mongodb disconnecting"
+                });
+                break;
+        };
+        return errors;
+    }
+};

routes/index.js

@@ -1,5 +1,6 @@
 var system = require('../system'),
     homepage = require('./homepage'),
+    health_routes = require('./health'),
     passport = require('passport'),
     account_routes = require('./account'),
     devices_routes = require('./devices'),
@@ -57,6 +58,9 @@ Routes.prototype.setupGeneralRoutes = function (app) {
     // General homepage
     app.get('/', this.setOpenhab, homepage.index);
 
+    // Health page
+    app.get('/health', this.setOpenhab, health_routes.gethealth);
+
     // Events
     app.get('/events', this.ensureAuthenticated, this.setOpenhab, events_routes.eventsget);