Address feedback

docs/source/api/apollo-gateway.mdx

@@ -267,7 +267,7 @@ Provide this field **only** if you are using managed federation _and_ your use c
 
 The maximum number of times the gateway retries a failed poll request to Apollo Uplink, cycling through its list of [`uplinkEndpoints`](#uplinkendpoints).
 
-The default value is three times your number of `uplinkEndpoints` (i.e., `6` in almost all cases).
+The default value is to try each of your uplinkEndpoints three times (i.e., 5 retries with the default list of two endpoints).
 
 Provide this field **only** if you are using managed federation.
 

gateway-js/src/index.ts

@@ -400,7 +400,7 @@ export class ApolloGateway implements GraphQLService {
           apiKey: this.apolloConfig!.key!,
           uplinkEndpoints,
           maxRetries:
-            this.config.uplinkMaxRetries ?? uplinkEndpoints.length * 3,
+            this.config.uplinkMaxRetries ?? uplinkEndpoints.length * 3 - 1, // -1 for the initial request
           subgraphHealthCheck: this.config.serviceHealthCheck,
           fetcher: this.fetcher,
           logger: this.logger,

gateway-js/src/supergraphManagers/UplinkFetcher/index.ts

@@ -82,7 +82,7 @@ export class UplinkFetcher implements SupergraphManager {
       fetcher: this.config.fetcher,
       compositionId: this.compositionId ?? null,
       maxRetries: this.config.maxRetries,
-      roundRobinSeed: this.fetchCount,
+      roundRobinSeed: this.fetchCount++,
     });
 
     if (!result) {

gateway-js/src/supergraphManagers/UplinkFetcher/loadSupergraphSdlFromStorage.ts

@@ -66,37 +66,24 @@ export async function loadSupergraphSdlFromUplinks({
   maxRetries: number,
   roundRobinSeed: number,
 }) : Promise<SupergraphSdlUpdate | null> {
-  let lastException = null;
-  let result: SupergraphSdlUpdate | null = null;
-
-  await retry(
-    async () => {
-      result = await loadSupergraphSdlFromStorage({
+  // This Promise resolves with either an updated supergraph or null if no change.
+  // This Promise can reject in the case that none of the retries are successful,
+  // in which case it will reject with the most frequently encountered error.
+  return retry(
+    () =>
+      loadSupergraphSdlFromStorage({
         graphRef,
         apiKey,
         endpoint: endpoints[roundRobinSeed++ % endpoints.length],
         errorReportingEndpoint,
         fetcher,
         compositionId,
-      });
-
-      // If we make it here, we didn't throw on this attempt. We'll clear
-      // any error we might've captured so we don't throw it below.
-      lastException = null;
-      return result;
-    },
+      }),
     {
       retries: maxRetries,
-      onRetry(err) {
-        lastException = err;
-      },
     },
   );
 
-  if (lastException !== null) {
-    throw lastException;
-  }
-  return result;
 }
 
 export async function loadSupergraphSdlFromStorage({