Network map (#1546)

* Initial iterative rewrite of network scan

* Remove unused linkKey

* Restore original log message

* Cleaner array flattening

* Fix various travis warnings

* Add a timeout so partial map can be generated

* Fix further eslint issues

* Add a timeout so partial map can be generated

* Fix further eslint issues

lib/zigbee.js

@@ -292,6 +292,18 @@ class Zigbee {
     networkScan(callback) {
         logger.info('Starting network scan...');
 
+        Promise.delay = function(t, val) {
+            return new Promise((resolve) => {
+                setTimeout(resolve.bind(null, val), t);
+            });
+        };
+
+        Promise.raceAll = function(promises, timeoutTime, timeoutVal) {
+            return Promise.all(promises.map((p) => {
+                return Promise.race([p, Promise.delay(timeoutTime, timeoutVal)]);
+            }));
+        };
+
         const processResponse = function(parent, shepherd) {
             return function(data) {
                 const linkSet = [];
@@ -310,12 +322,13 @@ class Zigbee {
         const allScans = this.getScanable().map((dev) => {
             return this.shepherd.lqi(dev.ieeeAddr).then(processResponse(dev.ieeeAddr, this.shepherd));
         }, this);
-        Promise.all(allScans).then((linkSets) => {
+        // Collect all lqi scans but timeout after 2 seconds if any fail
+        Promise.raceAll(allScans, 2000, []).then((linkSets) => {
             const linkMap = [].concat(...linkSets);
             logger.info('Network scan completed');
             callback(linkMap);
         })
-            .catch(function() {
+            .catch(function(result) {
                 logger.info('Network scan failed');
                 callback([]);
             });