Merge pull request #2929 from murgatroid99/grpc-js-xds_dependency_manager_watcher_updates

grpc-js-xds: Implement updated xds dependency manager watcher API

Author: murgatroid99

packages/grpc-js-xds/src/resolver-xds.ts

@@ -135,18 +135,12 @@ class XdsResolver implements Resolver {
       this.xdsClient = getSingletonXdsClient();
     }
     this.xdsConfigWatcher = {
-      onUpdate: xdsConfig => {
-        this.handleXdsConfig(xdsConfig);
-      },
-      onError: (context, status) => {
-        trace('Resolution error for target ' + uriToString(this.target) + ' due to xDS client transient error retrieving ' + context + ': ' + status.details);
-        this.reportResolutionError(`Error retrieving resource ${context}: ${status.details}`);
-      },
-      onResourceDoesNotExist: context => {
-        trace('Resolution error for target ' + uriToString(this.target) + ': ' + context + ' does not exist');
-        /* Return an empty endpoint list and service config, to explicitly
-         * invalidate any previously returned service config */
-        this.listener(statusOrFromValue([]), {}, null, '');
+      onUpdate: maybeXdsConfig => {
+        if (maybeXdsConfig.ok) {
+          this.handleXdsConfig(maybeXdsConfig.value);
+        } else {
+          this.listener(statusOrFromValue([]), {}, null, `Resolution error for target ${uriToString(this.target)}: ${maybeXdsConfig.error.details}`);
+        }
       }
     }
   }

packages/grpc-js-xds/src/xds-dependency-manager.ts

@@ -89,9 +89,7 @@ export interface XdsConfig {
 }
 
 export interface XdsConfigWatcher {
-  onUpdate(xdsConfig: XdsConfig): void;
-  onError(context: string, status: StatusObject): void;
-  onResourceDoesNotExist(context: string): void;
+  onUpdate(xdsConfig: StatusOr<XdsConfig>): void;
 }
 
 interface AggregateClusterInfo {
@@ -394,7 +392,13 @@ export class XdsDependencyManager {
          * not already provided a ServiceConfig for the upper layer to use */
         if (!this.latestListener) {
           this.trace('Resolution error due to xDS client transient error ' + error.details);
-          this.watcher.onError(`Listener ${listenerResourceName}`, error);
+          this.watcher.onUpdate({
+            ok: false,
+            error: {
+              ...error,
+              details: `Listener ${listenerResourceName}: ${error.details}`
+            }
+          });
         }
       },
       onResourceDoesNotExist: () => {
@@ -408,11 +412,24 @@ export class XdsDependencyManager {
       },
       onError: (error: StatusObject) => {
         if (!this.latestRouteConfiguration) {
-          this.watcher.onError(`RouteConfiguration ${this.latestRouteConfigName}`, error);
+          this.watcher.onUpdate({
+            ok: false,
+            error: {
+              ...error,
+              details: `RouteConfiguration ${this.latestRouteConfigName}: ${error.details}`
+            }
+          });
         }
       },
       onResourceDoesNotExist: () => {
-        this.watcher.onResourceDoesNotExist(`RouteConfiguration ${this.latestRouteConfigName}`);
+        this.watcher.onUpdate({
+          ok: false,
+          error: {
+            code: status.UNAVAILABLE,
+            details: `RouteConfiguration ${this.latestRouteConfigName} does not exist`,
+            metadata: new Metadata()
+          }
+        });
         this.clusterRoots = [];
         this.pruneOrphanClusters();
       }
@@ -434,8 +451,14 @@ export class XdsDependencyManager {
       this.clusterRoots = [];
       this.pruneOrphanClusters();
     }
-    this.watcher.onResourceDoesNotExist(`Listener ${this.listenerResourceName}`);
-
+    this.watcher.onUpdate({
+      ok: false,
+      error: {
+        code: status.UNAVAILABLE,
+        details: `Listener ${this.listenerResourceName} does not exist`,
+        metadata: new Metadata()
+      }
+    });
   }
 
   private maybeSendUpdate() {
@@ -491,7 +514,7 @@ export class XdsDependencyManager {
         });
       }
     }
-    this.watcher.onUpdate(update);
+    this.watcher.onUpdate({ok: true, value: update});
   }
 
   private addCluster(clusterName: string) {
@@ -763,10 +786,13 @@ export class XdsDependencyManager {
     if (!virtualHost) {
       this.clusterRoots = [];
       this.pruneOrphanClusters();
-      this.watcher.onError(`RouteConfiguration ${routeConfig.name}`, {
-        code: status.UNAVAILABLE,
-        details: `No matching route found for ${this.dataPlaneAuthority}`,
-        metadata: new Metadata()
+      this.watcher.onUpdate({
+        ok: false,
+        error: {
+          code: status.UNAVAILABLE,
+          details: `RouteConfiguration ${routeConfig.name}: No matching route found for ${this.dataPlaneAuthority}`,
+          metadata: new Metadata()
+        }
       });
       // Report error
       return;