added workaround for 'added' field compatible to MongoDB 3.6

manifest.yml

@@ -3,7 +3,7 @@ applications:
   - name: definma-api
     path: dist/
     instances: 1
-    memory: 512M
+    memory: 1024M
     stack: cflinuxfs3
     buildpacks:
       - nodejs_buildpack

package.json

@@ -9,7 +9,7 @@
     "build": "build.bat",
     "build-push": "build.bat && cf push",
     "test": "mocha dist/**/**.spec.js",
-    "start": "sleep 5s && node index.js",
+    "start": "node index.js",
     "dev": "nodemon -e ts,yaml --exec \"tsc && node dist/index.js || exit 1\"",
     "loadDev": "node dist/test/loadDev.js",
     "coverage": "tsc && nyc --reporter=html --reporter=text mocha dist/**/**.spec.js --timeout 5000",

src/db.ts

@@ -47,10 +47,15 @@ export default class db {
       if (err) done(err);
     });
     mongoose.connection.on('error', console.error.bind(console, 'connection error:'));
+    mongoose.connection.on('connected', () => {  // evaluation connection behaviour on prod
+      if (process.env.NODE_ENV !== 'test') {  // Do not interfere with testing
+        console.info('Database connected');
+      }
+    });
     mongoose.connection.on('disconnected', () => {  // reset state on disconnect
       if (process.env.NODE_ENV !== 'test') {  // Do not interfere with testing
         console.info('Database disconnected');
-        this.state.db = 0;
+        // this.state.db = 0;   // prod database connects and disconnects automatically
       }
     });
     process.on('SIGINT', () => {  // close connection when app is terminated

src/routes/sample.ts

@@ -256,7 +256,7 @@ router.get('/samples', async (req, res, next) => {
     // projection.added = {$toDate: '$_id'};
     // projection.added = { $convert: { input: '$_id', to: "date" } }  // TODO: upgrade MongoDB version or find alternative
   }
-  if (!(filters.fields.indexOf('_id') >= 0)) {  // disable _id explicitly
+  if (filters.fields.indexOf('_id') < 0 && filters.fields.indexOf('added') < 0) {  // disable _id explicitly
     projection._id = false;
   }
   queryPtr.push({$project: projection});
@@ -266,8 +266,18 @@ router.get('/samples', async (req, res, next) => {
       if (err) return next(err);
       if (data[0].count) {
         res.header('x-total-items', data[0].count.length > 0 ? data[0].count[0].count : 0);
+        res.header('Access-Control-Expose-Headers', 'x-total-items');
         data = data[0].samples;
       }
+      if (filters.fields.indexOf('added') >= 0) {  // add added date
+        data.map(e => {
+          e.added = e._id.getTimestamp();
+          if (filters.fields.indexOf('_id') < 0) {
+            delete e._id;
+          }
+          return e
+        });
+      }
       if (filters['to-page'] < 0) {
         data.reverse();
       }
@@ -289,7 +299,15 @@ router.get('/samples', async (req, res, next) => {
     res.write('[');
     let count = 0;
     const stream = collection.aggregate(query).cursor().exec();
-    stream.on('data', data => { res.write((count === 0 ? '' : ',\n') + JSON.stringify(data)); count ++; });
+    stream.on('data', data => {
+      if (filters.fields.indexOf('added') >= 0) {  // add added date
+        data.added = data._id.getTimestamp();
+        if (filters.fields.indexOf('_id') < 0) {
+          delete data._id;
+        }
+      }
+      res.write((count === 0 ? '' : ',\n') + JSON.stringify(data)); count ++;
+    });
     stream.on('close', () => {
       res.write(']');
       res.end();