Add functions for DB access

server/db.js

@@ -0,0 +1,67 @@
+"use strict";
+
+const MongoClient = require("mongodb").MongoClient;
+const config = require("./config");
+const apiFunctions = require("./api-functions");
+
+let _client = null;
+
+function getClient() {
+  if (_client) return Promise.resolve(_client);
+
+  return new Promise((resolve, reject) => {
+    const CONNECTION_URL = config.get("server.mongodbConnectionUrl");
+    MongoClient.connect(CONNECTION_URL, (err, client) => {
+      if (err) return reject(err);
+      resolve((_client = client.db("genieacs-ui")));
+    });
+  });
+}
+
+function query(resource, filter, limit, skip, callback) {
+  let q;
+  if (filter && filter.ast) q = apiFunctions.filterToMongoQuery(filter.ast);
+
+  return new Promise((resolve, reject) => {
+    getClient().then(client => {
+      const collection = client.collection(resource);
+      if (!callback)
+        collection
+          .find(q)
+          .skip(skip || 0)
+          .limit(limit || 0)
+          .toArray((err, docs) => {
+            if (err) return reject(err);
+            return resolve(docs);
+          });
+      else
+        collection.find(q).forEach(
+          doc => {
+            callback(doc);
+          },
+          err => {
+            if (err) reject(err);
+            else resolve();
+          }
+        );
+    });
+  });
+}
+
+function count(resource, filter) {
+  let q;
+  if (filter && filter.ast) q = apiFunctions.filterToMongoQuery(filter.ast);
+
+  return new Promise((resolve, reject) => {
+    getClient().then(client => {
+      const collection = client.collection(resource);
+      collection.find(q).count((err, c) => {
+        if (err) reject(err);
+        else resolve(c);
+      });
+    });
+  });
+}
+
+exports.query = query;
+exports.count = count;