feat(polling): Added an optional ability to specify a polling interval

getStream now accepts an optional second parameter that must be a positive number. If not specified,
it defaults to an 8s polling interval.

src/index.js

@@ -1,13 +1,21 @@
 import {Observable} from 'rx-lite';
 import fetchJsonp from 'fetch-jsonp';
 
-const getStream = (collectionId) => {
+const getStream = (collectionId, intervalSeconds = 8) => {
 
     if (!collectionId) {
         throw new Error('Please specify a collectionId');
     }
 
-    const pollRate = 8 * 1000;
+    if (typeof(intervalSeconds) !== 'number') {
+        throw new Error(`Polling interval should be a positive integer. A ${typeof(intervalSeconds)} was provided.`);
+    }
+
+    if (intervalSeconds <= 0) {
+        throw new Error(`Polling interval should be a positive integer. ${intervalSeconds} was specified.`);
+    }
+
+    const pollRate =  intervalSeconds * 1000;
 
     const requestStream = Observable.just(`http://app.climb.social/api/v1/collections/${collectionId}`);
 

src/index.test.js

@@ -37,6 +37,47 @@ describe('Climb.social library', () => {
 
         });
 
+        it('should accept an optional polling interval value', () => {
+
+            expect(() => {
+                const stream = climb.getStream(collectionId, 0.001);
+            }).to.not.throw();
+
+            expect(() => {
+                const stream = climb.getStream(collectionId, 5);
+            }).to.not.throw();
+
+            expect(() => {
+                const stream = climb.getStream(collectionId, 50000);
+            }).to.not.throw();
+
+        });
+
+        it('should error with a negative polling value', () => {
+
+            expect(() => {
+                const stream = climb.getStream(collectionId, -200);
+            }).to.throw();
+
+            expect(() => {
+                const stream = climb.getStream(collectionId, 0);
+            }).to.throw();
+
+            expect(() => {
+                const stream = climb.getStream(collectionId, -0.00001);
+            }).to.throw();
+
+        });
+
+
+        it('should error if interval length is not a interval', () => {
+
+            expect(() => {
+                const stream = climb.getStream(collectionId, '8');
+            }).to.throw();
+
+        });
+
         it('should return an object with a `subscribe()` method (an Observable)', () => {
 
             const stream = climb.getStream(collectionId);