SERVER-41134 Add RSM::findHostsWithMaxWait

Add support for a new method on the ReplicaSetMonitor, which finds all
acceptable hosts for a read preference (rather than just a single host).

This should use existing selection logic to return the host that would
be returned by findHostWithMaxWait in the [0]th element

1 files changed, 6 insertions, 0 deletions

diff --git a/src/mongo/client/replica_set_monitor.h b/src/mongo/client/replica_set_monitor.h
index b28364c6a25..92aa3a15add 100644
--- a/src/mongo/client/replica_set_monitor.h
+++ b/src/mongo/client/replica_set_monitor.h
@@ -90,6 +90,9 @@ public:
     SemiFuture<HostAndPort> getHostOrRefresh(const ReadPreferenceSetting& readPref,
                                              Milliseconds maxWait = kDefaultFindHostTimeout);
 
+    SemiFuture<std::vector<HostAndPort>> getHostsOrRefresh(
+        const ReadPreferenceSetting& readPref, Milliseconds maxWait = kDefaultFindHostTimeout);
+
     /**
      * Returns the host we think is the current master or uasserts.
      *
@@ -258,6 +261,9 @@ public:
     void runScanForMockReplicaSet();
 
 private:
+    Future<std::vector<HostAndPort>> _getHostsOrRefresh(const ReadPreferenceSetting& readPref,
+                                                        Milliseconds maxWait);
+
     /**
      * Schedules a refresh via the task executor. (Task is automatically canceled in the d-tor.)
      */