Allow configuring a datasource to poll instead of block (#8805)

ui-v2/app/serializers/application.js

@@ -107,10 +107,6 @@ export default Serializer.extend({
   // say `normalizeQueryResponse`
   // TODO: consider creating a method for each one of the `normalize...Response` family
   normalizeResponse: function(store, modelClass, payload, id, requestType) {
-    // Pick the meta/headers back off the payload and cleanup
-    // before we go through serializing
-    const headers = payload[HTTP_HEADERS_SYMBOL] || {};
-    delete payload[HTTP_HEADERS_SYMBOL];
     const normalizedPayload = this.normalizePayload(payload, id, requestType);
     // put the meta onto the response, here this is ok
     // as JSON-API allows this and our specific data is now in
@@ -119,7 +115,7 @@ export default Serializer.extend({
     // (which was the reason for the Symbol-like property earlier)
     // use a method modelled on ember-data methods so we have the opportunity to
     // do this on a per-model level
-    const meta = this.normalizeMeta(store, modelClass, headers, normalizedPayload, id, requestType);
+    const meta = this.normalizeMeta(store, modelClass, normalizedPayload, id, requestType);
     if (requestType !== 'query') {
       normalizedPayload.meta = meta;
     }
@@ -148,7 +144,10 @@ export default Serializer.extend({
   timestamp: function() {
     return new Date().getTime();
   },
-  normalizeMeta: function(store, modelClass, headers, payload, id, requestType) {
+  normalizeMeta: function(store, modelClass, payload, id, requestType) {
+    // Pick the meta/headers back off the payload and cleanup
+    const headers = payload[HTTP_HEADERS_SYMBOL] || {};
+    delete payload[HTTP_HEADERS_SYMBOL];
     const meta = {
       cacheControl: headers[HTTP_HEADERS_CACHE_CONTROL.toLowerCase()],
       cursor: headers[HTTP_HEADERS_INDEX.toLowerCase()],
@@ -158,6 +157,9 @@ export default Serializer.extend({
     if (typeof headers['x-range'] !== 'undefined') {
       meta.range = headers['x-range'];
     }
+    if (typeof headers['refresh'] !== 'undefined') {
+      meta.interval = headers['refresh'] * 1000;
+    }
     if (requestType === 'query') {
       meta.date = this.timestamp();
       payload.forEach(function(item) {

ui-v2/app/services/client/http.js

@@ -70,7 +70,7 @@ const parseBody = function(strs, ...values) {
   return [body, ...values];
 };
 
-const CLIENT_HEADERS = [CACHE_CONTROL, 'X-Request-ID', 'X-Range'];
+const CLIENT_HEADERS = [CACHE_CONTROL, 'X-Request-ID', 'X-Range', 'Refresh'];
 export default Service.extend({
   dom: service('dom'),
   connections: service('client/connections'),

ui-v2/app/services/data-source/protocols/http/blocking.js

@@ -17,8 +17,9 @@ export default Service.extend({
       return maybeCall(deleteCursor, ifNotBlocking(this.settings))().then(() => {
         return find(configuration)
           .then(maybeCall(close, ifNotBlocking(this.settings)))
-          .then(function(res) {
-            if (typeof get(res || {}, 'meta.cursor') === 'undefined') {
+          .then(function(res = {}) {
+            const meta = get(res, 'meta') || {};
+            if (typeof meta.cursor === 'undefined' && typeof meta.interval === 'undefined') {
               close();
             }
             return res;

ui-v2/app/utils/dom/event-source/blocking.js

@@ -44,7 +44,7 @@ const throttle = function(configuration, prev, current) {
     return new Promise(function(resolve, reject) {
       setTimeout(function() {
         resolve(obj);
-      }, pause);
+      }, configuration.interval || pause);
     });
   };
 };
@@ -104,6 +104,7 @@ export default function(EventSource, backoff = createErrorBackoff()) {
               // along with cursor validation
               configuration.cursor = validateCursor(meta.cursor, configuration.cursor);
               configuration.cacheControl = meta.cacheControl;
+              configuration.interval = meta.interval;
             }
             if ((configuration.cacheControl || '').indexOf('no-store') === -1) {
               this.currentEvent = event;