Change Resource.get() semantics and support X-Weave-Alert (bug #478330)

--HG--
extra : rebase_source : e0eb1e34f85ddd041005d780590640005dc0b434

services/sync/modules/engines.js

@@ -218,7 +218,10 @@ SyncEngine.prototype = {
   __proto__: Engine.prototype,
 
   _recordObj: CryptoWrapper,
-
+  
+  _alerts: "",
+  get alerts() { return this._alerts; },
+  
   get baseURL() {
     let url = Svc.Prefs.get("clusterURL");
     if (!url)
@@ -341,8 +344,15 @@ SyncEngine.prototype = {
       Sync.sleep(0);
     });
 
-    newitems.get();
-
+    let resp = newitems.get();
+    try {
+      // we only need to store the latest alert
+      this._alerts = resp.getHeader("X-Weave-Alert");
+    } catch (e) {
+      // no alert headers were present
+      this._alerts = "";
+    }
+    
     if (this.lastSync < this._lastSyncTmp)
         this.lastSync = this._lastSyncTmp;
 

services/sync/modules/resource.js

@@ -50,6 +50,23 @@ Cu.import("resource://weave/constants.js");
 Cu.import("resource://weave/util.js");
 Cu.import("resource://weave/auth.js");
 
+// = RequestResponse =
+//
+// This object is returned on a successful
+// HTTP response (codes 200-300) and encapsulates
+// returned headers and the actual response text
+function RequestResponse(channel, response) {
+  this._channel = channel;
+  this._response = response;
+}
+RequestResponse.prototype = {
+  get response() { return this._response },
+  get status() { return this._channel.responseStatus },
+  getHeader: function ReqRe_getHeader(which) {
+    return this._channel.getResponseHeader(which);
+  }
+};
+
 // = RequestException =
 //
 // This function raises an exception through the call
@@ -293,7 +310,7 @@ Resource.prototype = {
       this._log.debug(action + " request failed (" + channel.responseStatus + ")");
       if (this._data)
         this._log.debug("Error response: " + this._data);
-      throw new RequestException(this, action, channel);
+      return new RequestResponse(channel, this._data);
 
     } else {
       this._log.debug(action + " request successful (" + channel.responseStatus  + ")");
@@ -313,7 +330,7 @@ Resource.prototype = {
       }
     }
 
-    return this._data;
+    return new RequestResponse(channel, this._data);
   },
 
   // ** {{{ Resource.get }}} **

services/sync/modules/service.js

@@ -172,6 +172,10 @@ WeaveSvc.prototype = {
   // Timer object for automagically syncing
   _syncTimer: null,
 
+  // Current alerts
+  _alerts: "[]",
+  get alerts() { return JSON.parse(this._alerts); },
+  
   get username() {
     return Svc.Prefs.get("username", "");
   },
@@ -532,17 +536,38 @@ WeaveSvc.prototype = {
       };
 
       // login may fail because of cluster change
+      let response;
       try {
-        res.get();
+        response = res.get();
       } catch (e) {}
 
-      try {
-        switch (res.lastChannel.responseStatus) {
+      if (response) {
+        switch (response.status) {
           case 200:
-            if (passphrase && !this.verifyPassphrase(username, password, passphrase)) {
+            if (passphrase &&
+              !this.verifyPassphrase(username, password, passphrase)) {
               this._setSyncFailure(LOGIN_FAILED_INVALID_PASSPHRASE);
               return false;
             }
+            
+            // check for alerts
+            try {
+              let alerts = response.getHeader("X-Weave-Alert");
+              if (this._alerts != alerts) {
+                this._alerts = alerts;
+                Svc.Observer.notifyObservers(
+                  null, "weave:service:alerts:changed", ""
+                );
+              }
+            } catch (e) {
+              // no alert headers were present
+              if (this.alerts.length != 0) {
+                this._alerts = "";
+                Svc.Observer.notifyObservers(
+                  null, "weave:service:alerts:changed", ""
+                );
+              }
+            }
             return true;
           case 401:
             if (this.updateCluster(username))
@@ -554,9 +579,9 @@ WeaveSvc.prototype = {
           default:
             throw "unexpected HTTP response: " + res.lastChannel.responseStatus;
         }
-      } catch (e) {
+      } else {
         // if we get here, we have either a busted channel or a network error
-        this._log.debug("verifyLogin failed: " + e)
+        this._log.debug("verifyLogin failed: network error");
         this._setSyncFailure(LOGIN_FAILED_NETWORK_ERROR);
         throw e;
       }
@@ -1222,6 +1247,12 @@ WeaveSvc.prototype = {
   _syncEngine: function WeaveSvc__syncEngine(engine) {
     try {
       engine.sync();
+      if (this._alerts != engine.alerts) {
+        this._alerts = engine.alerts;
+        Svc.Observer.notifyObservers(
+          null, "weave:service:alerts:changed", ""
+        );
+      }
       return true;
     }
     catch(e) {