Revert "SERVER-49988 Rename response fields if hello command is sent on mongos"

This reverts commit 2fa244c0e70dfe80a248747cca49ceacefd9cb50.

3 files changed, 7 insertions, 23 deletions

diff --git a/jstests/core/ismaster.js b/jstests/core/ismaster.js
index 5f309b83392..a8ed96a4ac1 100644
--- a/jstests/core/ismaster.js
+++ b/jstests/core/ismaster.js
@@ -16,7 +16,7 @@ function checkResponseFields(commandString) {
            "maxWriteBatchSize possibly missing:" + tojson(res));
     assert.eq("boolean", typeof res.ismaster, "ismaster field is not a boolean" + tojson(res));
 
-    // TODO SERVER-49987: Check for res.isWritablePrimary instead of res.ismaster if a hello command
+    // TODO SERVER-49988: Check for res.isWritablePrimary instead of res.ismaster if a hello command
     // was executed.
     assert(res.ismaster === true, "ismaster field is false" + tojson(res));
     assert(res.localTime, "localTime possibly missing:" + tojson(res));
@@ -56,8 +56,6 @@ function checkResponseFields(commandString) {
     }
 }
 
-// TODO SERVER-49987: add the "hello" command test back in once mongod response fields are
-// appropriately changed.
-// checkResponseFields("hello");
+checkResponseFields("hello");
 checkResponseFields("ismaster");
 checkResponseFields("isMaster");
diff --git a/jstests/sharding/ismaster.js b/jstests/sharding/ismaster.js
index 185294200ac..a582f677241 100644
--- a/jstests/sharding/ismaster.js
+++ b/jstests/sharding/ismaster.js
@@ -16,15 +16,10 @@ function checkResponseFields(commandString) {
         res.maxMessageSizeBytes && isNumber(res.maxMessageSizeBytes) && res.maxBsonObjectSize > 0,
         "maxMessageSizeBytes possibly missing:" + tojson(res));
 
-    if (commandString === "hello") {
-        assert.eq("boolean",
-                  typeof res.isWritablePrimary,
-                  "isWritablePrimary field is not a boolean" + tojson(res));
-        assert(res.isWritablePrimary === true, "isWritablePrimary field is false" + tojson(res));
-    } else {
-        assert.eq("boolean", typeof res.ismaster, "ismaster field is not a boolean" + tojson(res));
-        assert(res.ismaster === true, "ismaster field is false" + tojson(res));
-    }
+    // TODO SERVER-49988: Check for res.isWritablePrimary instead of res.ismaster if a hello command
+    // was executed.
+    assert.eq("boolean", typeof res.ismaster, "ismaster field is not a boolean" + tojson(res));
+    assert(res.ismaster === true, "ismaster field is false" + tojson(res));
 
     assert(res.localTime, "localTime possibly missing:" + tojson(res));
     assert(res.msg && res.msg == "isdbgrid", "msg possibly missing or wrong:" + tojson(res));
diff --git a/src/mongo/s/commands/cluster_is_master_cmd.cpp b/src/mongo/s/commands/cluster_is_master_cmd.cpp
index 08a3da77615..bb0fb7fec3b 100644
--- a/src/mongo/s/commands/cluster_is_master_cmd.cpp
+++ b/src/mongo/s/commands/cluster_is_master_cmd.cpp
@@ -109,11 +109,6 @@ public:
 
         waitInIsMaster.pauseWhileSet(opCtx);
 
-        // Parse the command name, which should be one of the following: hello, isMaster, or
-        // ismaster. If the command is "hello", we must attach an "isWritablePrimary" response field
-        // instead of "ismaster".
-        bool useLegacyResponseFields = (cmdObj.firstElementFieldNameStringData() != kHelloString);
-
         auto& clientMetadataIsMasterState = ClientMetadataIsMasterState::get(opCtx->getClient());
         bool seenIsMaster = clientMetadataIsMasterState.hasSeenIsMaster();
         if (!seenIsMaster) {
@@ -193,11 +188,7 @@ public:
         }
 
         auto result = replyBuilder->getBodyBuilder();
-        if (useLegacyResponseFields) {
-            result.appendBool("ismaster", true);
-        } else {
-            result.appendBool("isWritablePrimary", true);
-        }
+        result.appendBool("ismaster", true);
         result.append("msg", "isdbgrid");
         result.appendNumber("maxBsonObjectSize", BSONObjMaxUserSize);
         result.appendNumber("maxMessageSizeBytes", MaxMessageSizeBytes);