clean up logic

mongodb · May 10, 2024 · 72c22b9 · 72c22b9
1 parent 5c91311
commit 72c22b9
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Showing 2 changed files with 20 additions and 9 deletions.
diff --git a/src/cmap/connection_pool.ts b/src/cmap/connection_pool.ts
@@ -370,12 +370,20 @@ export class ConnectionPool extends TypedEventEmitter<ConnectionPoolEvents> {
       // CSOT enabled
       // Determine if we're using the timeout passed in or a new timeout
       if (options.timeout.duration > 0 || serverSelectionTimeoutMS > 0) {
+        // This check determines whether or not Topology.selectServer used the configured
+        // `timeoutMS` or `serverSelectionTimeoutMS` value for its timeout
         if (
-          csotMin(options.timeout.duration, serverSelectionTimeoutMS) === serverSelectionTimeoutMS
+          options.timeout.duration === serverSelectionTimeoutMS ||
+          csotMin(options.timeout.duration, serverSelectionTimeoutMS) < serverSelectionTimeoutMS
         ) {
-          timeout = Timeout.expires(serverSelectionTimeoutMS - options.timeout.timeElapsed);
-        } else {
+          // server selection used `timeoutMS`, so we should use the existing timeout as the timeout
+          // here
           timeout = options.timeout;
+        } else {
+          // server selection used `serverSelectionTimeoutMS`, so we construct a new timeout with
+          // the time remaining to ensure that Topology.selectServer and ConnectionPool.checkOut
+          // cumulatively don't spend more than `serverSelectionTimeoutMS` blocking
+          timeout = Timeout.expires(serverSelectionTimeoutMS - options.timeout.timeElapsed);
         }
       }
     } else {

diff --git a/src/sdam/topology.ts b/src/sdam/topology.ts
@@ -38,6 +38,7 @@ import { Timeout, TimeoutError } from '../timeout';
 import type { Transaction } from '../transactions';
 import {
   type Callback,
+  csotMin,
   type EventEmitterWithState,
   HostAddress,
   List,
@@ -563,18 +564,20 @@ export class Topology extends TypedEventEmitter<TopologyEvents> {
       );
     }
     const serverSelectionTimeoutMS = options.serverSelectionTimeoutMS ?? 0;
-    let timeout: Timeout | null = null;
+    let timeout: Timeout | null;
     if (options.timeout) {
       // CSOT Enabled
-      if (options.timeout.duration !== 0 || serverSelectionTimeoutMS !== 0) {
+      if (options.timeout.duration > 0 || serverSelectionTimeoutMS > 0) {
         if (
-          Math.min(options.timeout.remainingTime, serverSelectionTimeoutMS) ===
-          serverSelectionTimeoutMS
+          options.timeout.duration === serverSelectionTimeoutMS ||
+          csotMin(options.timeout.duration, serverSelectionTimeoutMS) < serverSelectionTimeoutMS
         ) {
-          timeout = Timeout.expires(serverSelectionTimeoutMS);
-        } else {
           timeout = options.timeout;
+        } else {
+          timeout = Timeout.expires(serverSelectionTimeoutMS);
         }
+      } else {
+        timeout = null;
       }
     } else {
       timeout = Timeout.expires(serverSelectionTimeoutMS);