diff options
Diffstat (limited to 'src/mongo/rpc/command_request.cpp')
| -rw-r--r-- | src/mongo/rpc/command_request.cpp | 15 |
1 files changed, 13 insertions, 2 deletions
diff --git a/src/mongo/rpc/command_request.cpp b/src/mongo/rpc/command_request.cpp index 08bb54e91fe..54cb58a4313 100644 --- a/src/mongo/rpc/command_request.cpp +++ b/src/mongo/rpc/command_request.cpp @@ -93,13 +93,24 @@ CommandRequest::CommandRequest(const Message* message) : _message(message) { _commandArgs.firstElementFieldName() == _commandName); // OP_COMMAND is only used when communicating with 3.4 nodes and they serialize their metadata - // fields differently. We do all up- and down-conversion here so that the rest of the code only - // has to deal with the current format. + // fields differently. We do all up-conversion here so that the rest of the code only has to + // deal with the current format. uassertStatusOK(cur.readAndAdvance<>(&obj)); BSONObjBuilder metadataBuilder; for (auto elem : obj.val) { if (elem.fieldNameStringData() == "configsvr") { metadataBuilder.appendAs(elem, "$configServerState"); + } else if (elem.fieldNameStringData() == "$ssm") { + auto ssmObj = elem.Obj(); + if (auto readPrefElem = ssmObj["$readPreference"]) { + // Promote the read preference to the top level. + metadataBuilder.append(readPrefElem); + } else if (ssmObj["$secondaryOk"].trueValue()) { + // Convert secondaryOk to equivalent read preference if none was explicitly + // provided. + ReadPreferenceSetting(ReadPreference::SecondaryPreferred) + .toContainingBSON(&metadataBuilder); + } } else { metadataBuilder.append(elem); } |