SERVER-23103 Move assembleResposne to its own library

33 files changed, 744 insertions, 687 deletions

diff --git a/src/mongo/db/SConscript b/src/mongo/db/SConscript
index 8370d39a01d..1b6d57eddef 100644
--- a/src/mongo/db/SConscript
+++ b/src/mongo/db/SConscript
@@ -606,7 +606,7 @@ env.Library(
         'lasterror',
     ],
     LIBDEPS_TAGS=[
-        # Depends on assembleResponse, defined in instance.cpp below.
+        # Circularity with assembleResponse, defined in assemble_response, below.
         'incomplete',
     ],
 )
@@ -803,6 +803,25 @@ env.Library(
     ],
 )
 
+env.Library(
+    target="assemble_response",
+    source=[
+        "assemble_response.cpp",
+    ],
+    LIBDEPS=[
+        "commands/dcommands",
+        "curop",
+        "curop_metrics",
+        "diag_log",
+        "introspect",
+        "lasterror",
+        "ops/write_ops",
+        "ops/write_ops_parsers",
+        "run_commands",
+        "storage/storage_options",
+    ],
+)
+
 # mongod files - also files used in tools. present in dbtests, but not in mongos and not in client
 # libs.
 serverOnlyFiles = [
@@ -826,6 +845,7 @@ serveronlyLibdeps = [
     "$BUILD_DIR/mongo/db/storage/mmap_v1/file_allocator",
     "$BUILD_DIR/third_party/shim_snappy",
     '$BUILD_DIR/mongo/db/ttl_collection_cache',
+    "assemble_response",
     "auth/authmongod",
     "background",
     "catalog/catalog",
diff --git a/src/mongo/db/assemble_response.cpp b/src/mongo/db/assemble_response.cpp
new file mode 100644
index 00000000000..c2da985db30
--- /dev/null
+++ b/src/mongo/db/assemble_response.cpp
@@ -0,0 +1,655 @@
+/**
+ *    Copyright (C) 2008-2014 MongoDB Inc.
+ *
+ *    This program is free software: you can redistribute it and/or  modify
+ *    it under the terms of the GNU Affero General Public License, version 3,
+ *    as published by the Free Software Foundation.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU Affero General Public License for more details.
+ *
+ *    You should have received a copy of the GNU Affero General Public License
+ *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the GNU Affero General Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#define MONGO_LOG_DEFAULT_COMPONENT ::mongo::logger::LogComponent::kCommand
+
+#include "mongo/platform/basic.h"
+
+#include "mongo/db/assemble_response.h"
+
+#include "mongo/db/audit.h"
+#include "mongo/db/auth/authorization_session.h"
+#include "mongo/db/catalog/cursor_manager.h"
+#include "mongo/db/commands/fsync.h"
+#include "mongo/db/curop.h"
+#include "mongo/db/curop_metrics.h"
+#include "mongo/db/dbdirectclient.h"
+#include "mongo/db/diag_log.h"
+#include "mongo/db/introspect.h"
+#include "mongo/db/jsobj.h"
+#include "mongo/db/lasterror.h"
+#include "mongo/db/ops/write_ops_exec.h"
+#include "mongo/db/ops/write_ops_parsers.h"
+#include "mongo/db/query/find.h"
+#include "mongo/db/run_commands.h"
+#include "mongo/db/s/sharded_connection_info.h"
+#include "mongo/db/s/sharding_state.h"
+#include "mongo/db/stats/counters.h"
+#include "mongo/db/stats/top.h"
+#include "mongo/rpc/command_reply_builder.h"
+#include "mongo/rpc/command_request.h"
+#include "mongo/rpc/legacy_reply_builder.h"
+#include "mongo/rpc/legacy_request.h"
+#include "mongo/s/stale_exception.h"
+#include "mongo/util/fail_point_service.h"
+#include "mongo/util/log.h"
+#include "mongo/util/net/message.h"
+
+namespace mongo {
+
+const HostAndPort kHostAndPortForDirectClient("0.0.0.0", 0);
+
+MONGO_FP_DECLARE(rsStopGetMore);
+
+namespace {
+using logger::LogComponent;
+
+inline void opread(Message& m) {
+    if (_diaglog.getLevel() & 2) {
+        _diaglog.readop(m.singleData().view2ptr(), m.header().getLen());
+    }
+}
+
+inline void opwrite(Message& m) {
+    if (_diaglog.getLevel() & 1) {
+        _diaglog.writeop(m.singleData().view2ptr(), m.header().getLen());
+    }
+}
+
+void generateLegacyQueryErrorResponse(const AssertionException* exception,
+                                      const QueryMessage& queryMessage,
+                                      CurOp* curop,
+                                      Message* response) {
+    curop->debug().exceptionInfo = exception->getInfo();
+
+    log(LogComponent::kQuery) << "assertion " << exception->toString() << " ns:" << queryMessage.ns
+                              << " query:" << (queryMessage.query.valid(BSONVersion::kLatest)
+                                                   ? queryMessage.query.toString()
+                                                   : "query object is corrupt");
+    if (queryMessage.ntoskip || queryMessage.ntoreturn) {
+        log(LogComponent::kQuery) << " ntoskip:" << queryMessage.ntoskip
+                                  << " ntoreturn:" << queryMessage.ntoreturn;
+    }
+
+    const SendStaleConfigException* scex = (exception->getCode() == ErrorCodes::SendStaleConfig)
+        ? static_cast<const SendStaleConfigException*>(exception)
+        : NULL;
+
+    BSONObjBuilder err;
+    exception->getInfo().append(err);
+    if (scex) {
+        err.append("ok", 0.0);
+        err.append("ns", scex->getns());
+        scex->getVersionReceived().addToBSON(err, "vReceived");
+        scex->getVersionWanted().addToBSON(err, "vWanted");
+    }
+    BSONObj errObj = err.done();
+
+    if (scex) {
+        log(LogComponent::kQuery) << "stale version detected during query over " << queryMessage.ns
+                                  << " : " << errObj;
+    }
+
+    BufBuilder bb;
+    bb.skip(sizeof(QueryResult::Value));
+    bb.appendBuf((void*)errObj.objdata(), errObj.objsize());
+
+    // TODO: call replyToQuery() from here instead of this!!! see dbmessage.h
+    QueryResult::View msgdata = bb.buf();
+    QueryResult::View qr = msgdata;
+    qr.setResultFlags(ResultFlag_ErrSet);
+    if (scex)
+        qr.setResultFlags(qr.getResultFlags() | ResultFlag_ShardConfigStale);
+    qr.msgdata().setLen(bb.len());
+    qr.msgdata().setOperation(opReply);
+    qr.setCursorId(0);
+    qr.setStartingFrom(0);
+    qr.setNReturned(1);
+    response->setData(bb.release());
+}
+
+/**
+ * Fills out CurOp / OpDebug with basic command info.
+ */
+void beginCommandOp(OperationContext* txn, const NamespaceString& nss, const BSONObj& queryObj) {
+    auto curop = CurOp::get(txn);
+    stdx::lock_guard<Client> lk(*txn->getClient());
+    curop->setQuery_inlock(queryObj);
+    curop->setNS_inlock(nss.ns());
+}
+
+void receivedCommand(OperationContext* txn,
+                     const NamespaceString& nss,
+                     Client& client,
+                     DbResponse& dbResponse,
+                     Message& message) {
+    invariant(nss.isCommand());
+
+    const int32_t responseToMsgId = message.header().getId();
+
+    DbMessage dbMessage(message);
+    QueryMessage queryMessage(dbMessage);
+
+    CurOp* op = CurOp::get(txn);
+
+    rpc::LegacyReplyBuilder builder{};
+
+    try {
+        // This will throw if the request is on an invalid namespace.
+        rpc::LegacyRequest request{&message};
+        // Auth checking for Commands happens later.
+        int nToReturn = queryMessage.ntoreturn;
+
+        beginCommandOp(txn, nss, request.getCommandArgs());
+
+        {
+            stdx::lock_guard<Client> lk(*txn->getClient());
+            op->markCommand_inlock();
+        }
+
+        uassert(16979,
+                str::stream() << "bad numberToReturn (" << nToReturn
+                              << ") for $cmd type ns - can only be 1 or -1",
+                nToReturn == 1 || nToReturn == -1);
+
+        runCommands(txn, request, &builder);
+
+        op->debug().iscommand = true;
+    } catch (const DBException& exception) {
+        Command::generateErrorResponse(txn, &builder, exception);
+    }
+
+    auto response = builder.done();
+
+    op->debug().responseLength = response.header().dataLen();
+
+    dbResponse.response = std::move(response);
+    dbResponse.responseToMsgId = responseToMsgId;
+}
+
+void receivedRpc(OperationContext* txn, Client& client, DbResponse& dbResponse, Message& message) {
+    invariant(message.operation() == dbCommand);
+
+    const int32_t responseToMsgId = message.header().getId();
+
+    rpc::CommandReplyBuilder replyBuilder{};
+
+    auto curOp = CurOp::get(txn);
+
+    try {
+        // database is validated here
+        rpc::CommandRequest request{&message};
+
+        // We construct a legacy $cmd namespace so we can fill in curOp using
+        // the existing logic that existed for OP_QUERY commands
+        NamespaceString nss(request.getDatabase(), "$cmd");
+        beginCommandOp(txn, nss, request.getCommandArgs());
+        {
+            stdx::lock_guard<Client> lk(*txn->getClient());
+            curOp->markCommand_inlock();
+        }
+
+        runCommands(txn, request, &replyBuilder);
+
+        curOp->debug().iscommand = true;
+
+    } catch (const DBException& exception) {
+        Command::generateErrorResponse(txn, &replyBuilder, exception);
+    }
+
+    auto response = replyBuilder.done();
+
+    curOp->debug().responseLength = response.header().dataLen();
+
+    dbResponse.response = std::move(response);
+    dbResponse.responseToMsgId = responseToMsgId;
+}
+
+// In SERVER-7775 we reimplemented the pseudo-commands fsyncUnlock, inProg, and killOp
+// as ordinary commands. To support old clients for another release, this helper serves
+// to execute the real command from the legacy pseudo-command codepath.
+// TODO: remove after MongoDB 3.2 is released
+void receivedPseudoCommand(OperationContext* txn,
+                           Client& client,
+                           DbResponse& dbResponse,
+                           Message& message,
+                           StringData realCommandName) {
+    DbMessage originalDbm(message);
+
+    auto originalNToSkip = originalDbm.pullInt();
+
+    uassert(ErrorCodes::InvalidOptions,
+            str::stream() << "invalid nToSkip - expected 0, but got " << originalNToSkip,
+            originalNToSkip == 0);
+
+    auto originalNToReturn = originalDbm.pullInt();
+
+    uassert(ErrorCodes::InvalidOptions,
+            str::stream() << "invalid nToReturn - expected -1 or 1, but got " << originalNToSkip,
+            originalNToReturn == -1 || originalNToReturn == 1);
+
+    auto cmdParams = originalDbm.nextJsObj();
+
+    Message interposed;
+    // HACK:
+    // legacy pseudo-commands could run on any database. The command replacements
+    // can only run on 'admin'. To avoid breaking old shells and a multitude
+    // of third-party tools, we rewrite the namespace. As auth is checked
+    // later in Command::_checkAuthorizationImpl, we will still properly
+    // reject the request if the client is not authorized.
+    NamespaceString interposedNss("admin", "$cmd");
+
+    BSONObjBuilder cmdBob;
+    cmdBob.append(realCommandName, 1);
+    cmdBob.appendElements(cmdParams);
+    auto cmd = cmdBob.done();
+
+    // TODO: use OP_COMMAND here instead of constructing
+    // a legacy OP_QUERY style command
+    BufBuilder cmdMsgBuf;
+
+    int32_t flags = DataView(message.header().data()).read<LittleEndian<int32_t>>();
+    cmdMsgBuf.appendNum(flags);
+
+    cmdMsgBuf.appendStr(interposedNss.db(), false);  // not including null byte
+    cmdMsgBuf.appendStr(".$cmd");
+    cmdMsgBuf.appendNum(0);  // ntoskip
+    cmdMsgBuf.appendNum(1);  // ntoreturn
+    cmdMsgBuf.appendBuf(cmd.objdata(), cmd.objsize());
+
+    interposed.setData(dbQuery, cmdMsgBuf.buf(), cmdMsgBuf.len());
+    interposed.header().setId(message.header().getId());
+
+    receivedCommand(txn, interposedNss, client, dbResponse, interposed);
+}
+
+void receivedQuery(OperationContext* txn,
+                   const NamespaceString& nss,
+                   Client& c,
+                   DbResponse& dbResponse,
+                   Message& m) {
+    invariant(!nss.isCommand());
+    globalOpCounters.gotQuery();
+
+    int32_t responseToMsgId = m.header().getId();
+
+    DbMessage d(m);
+    QueryMessage q(d);
+
+    CurOp& op = *CurOp::get(txn);
+
+    try {
+        Client* client = txn->getClient();
+        Status status = AuthorizationSession::get(client)->checkAuthForFind(nss, false);
+        audit::logQueryAuthzCheck(client, nss, q.query, status.code());
+        uassertStatusOK(status);
+
+        dbResponse.exhaustNS = runQuery(txn, q, nss, dbResponse.response);
+    } catch (const AssertionException& e) {
+        // If we got a stale config, wait in case the operation is stuck in a critical section
+        if (e.getCode() == ErrorCodes::SendStaleConfig) {
+            auto& sce = static_cast<const StaleConfigException&>(e);
+            ShardingState::get(txn)->onStaleShardVersion(
+                txn, NamespaceString(sce.getns()), sce.getVersionReceived());
+        }
+
+        dbResponse.response.reset();
+        generateLegacyQueryErrorResponse(&e, q, &op, &dbResponse.response);
+    }
+
+    op.debug().responseLength = dbResponse.response.header().dataLen();
+    dbResponse.responseToMsgId = responseToMsgId;
+}
+
+void receivedKillCursors(OperationContext* txn, Message& m) {
+    LastError::get(txn->getClient()).disable();
+    DbMessage dbmessage(m);
+    int n = dbmessage.pullInt();
+
+    uassert(13659, "sent 0 cursors to kill", n != 0);
+    massert(13658,
+            str::stream() << "bad kill cursors size: " << m.dataSize(),
+            m.dataSize() == 8 + (8 * n));
+    uassert(13004, str::stream() << "sent negative cursors to kill: " << n, n >= 1);
+
+    if (n > 2000) {
+        (n < 30000 ? warning() : error()) << "receivedKillCursors, n=" << n;
+        verify(n < 30000);
+    }
+
+    const char* cursorArray = dbmessage.getArray(n);
+
+    int found = CursorManager::eraseCursorGlobalIfAuthorized(txn, n, cursorArray);
+
+    if (shouldLog(logger::LogSeverity::Debug(1)) || found != n) {
+        LOG(found == n ? 1 : 0) << "killcursors: found " << found << " of " << n;
+    }
+}
+
+void receivedInsert(OperationContext* txn, const NamespaceString& nsString, Message& m) {
+    auto insertOp = parseLegacyInsert(m);
+    invariant(insertOp.ns == nsString);
+    for (const auto& obj : insertOp.documents) {
+        Status status =
+            AuthorizationSession::get(txn->getClient())->checkAuthForInsert(txn, nsString, obj);
+        audit::logInsertAuthzCheck(txn->getClient(), nsString, obj, status.code());
+        uassertStatusOK(status);
+    }
+    performInserts(txn, insertOp);
+}
+
+void receivedUpdate(OperationContext* txn, const NamespaceString& nsString, Message& m) {
+    auto updateOp = parseLegacyUpdate(m);
+    auto& singleUpdate = updateOp.updates[0];
+    invariant(updateOp.ns == nsString);
+
+    Status status =
+        AuthorizationSession::get(txn->getClient())
+            ->checkAuthForUpdate(
+                txn, nsString, singleUpdate.query, singleUpdate.update, singleUpdate.upsert);
+    audit::logUpdateAuthzCheck(txn->getClient(),
+                               nsString,
+                               singleUpdate.query,
+                               singleUpdate.update,
+                               singleUpdate.upsert,
+                               singleUpdate.multi,
+                               status.code());
+    uassertStatusOK(status);
+
+    performUpdates(txn, updateOp);
+}
+
+void receivedDelete(OperationContext* txn, const NamespaceString& nsString, Message& m) {
+    auto deleteOp = parseLegacyDelete(m);
+    auto& singleDelete = deleteOp.deletes[0];
+    invariant(deleteOp.ns == nsString);
+
+    Status status = AuthorizationSession::get(txn->getClient())
+                        ->checkAuthForDelete(txn, nsString, singleDelete.query);
+    audit::logDeleteAuthzCheck(txn->getClient(), nsString, singleDelete.query, status.code());
+    uassertStatusOK(status);
+
+    performDeletes(txn, deleteOp);
+}
+
+bool receivedGetMore(OperationContext* txn, DbResponse& dbresponse, Message& m, CurOp& curop) {
+    globalOpCounters.gotGetMore();
+    DbMessage d(m);
+
+    const char* ns = d.getns();
+    int ntoreturn = d.pullInt();
+    uassert(
+        34419, str::stream() << "Invalid ntoreturn for OP_GET_MORE: " << ntoreturn, ntoreturn >= 0);
+    long long cursorid = d.pullInt64();
+
+    curop.debug().ntoreturn = ntoreturn;
+    curop.debug().cursorid = cursorid;
+
+    {
+        stdx::lock_guard<Client>(*txn->getClient());
+        CurOp::get(txn)->setNS_inlock(ns);
+    }
+
+    bool exhaust = false;
+    bool isCursorAuthorized = false;
+
+    try {
+        const NamespaceString nsString(ns);
+        uassert(ErrorCodes::InvalidNamespace,
+                str::stream() << "Invalid ns [" << ns << "]",
+                nsString.isValid());
+
+        Status status = AuthorizationSession::get(txn->getClient())
+                            ->checkAuthForGetMore(nsString, cursorid, false);
+        audit::logGetMoreAuthzCheck(txn->getClient(), nsString, cursorid, status.code());
+        uassertStatusOK(status);
+
+        while (MONGO_FAIL_POINT(rsStopGetMore)) {
+            sleepmillis(0);
+        }
+
+        dbresponse.response = getMore(txn, ns, ntoreturn, cursorid, &exhaust, &isCursorAuthorized);
+    } catch (AssertionException& e) {
+        if (isCursorAuthorized) {
+            // If a cursor with id 'cursorid' was authorized, it may have been advanced
+            // before an exception terminated processGetMore.  Erase the ClientCursor
+            // because it may now be out of sync with the client's iteration state.
+            // SERVER-7952
+            // TODO Temporary code, see SERVER-4563 for a cleanup overview.
+            CursorManager::eraseCursorGlobal(txn, cursorid);
+        }
+
+        BSONObjBuilder err;
+        e.getInfo().append(err);
+        BSONObj errObj = err.done();
+
+        curop.debug().exceptionInfo = e.getInfo();
+
+        replyToQuery(ResultFlag_ErrSet, m, dbresponse, errObj);
+        curop.debug().responseLength = dbresponse.response.header().dataLen();
+        curop.debug().nreturned = 1;
+        return false;
+    }
+
+    curop.debug().responseLength = dbresponse.response.header().dataLen();
+    auto queryResult = QueryResult::ConstView(dbresponse.response.buf());
+    curop.debug().nreturned = queryResult.getNReturned();
+
+    dbresponse.responseToMsgId = m.header().getId();
+
+    if (exhaust) {
+        curop.debug().exhaust = true;
+        dbresponse.exhaustNS = ns;
+    }
+
+    return true;
+}
+
+}  // namespace
+
+// Returns false when request includes 'end'
+void assembleResponse(OperationContext* txn,
+                      Message& m,
+                      DbResponse& dbresponse,
+                      const HostAndPort& remote) {
+    // before we lock...
+    NetworkOp op = m.operation();
+    bool isCommand = false;
+
+    DbMessage dbmsg(m);
+
+    Client& c = *txn->getClient();
+    if (c.isInDirectClient()) {
+        invariant(!txn->lockState()->inAWriteUnitOfWork());
+    } else {
+        LastError::get(c).startRequest();
+        AuthorizationSession::get(c)->startRequest(txn);
+
+        // We should not be holding any locks at this point
+        invariant(!txn->lockState()->isLocked());
+    }
+
+    const char* ns = dbmsg.messageShouldHaveNs() ? dbmsg.getns() : NULL;
+    const NamespaceString nsString = ns ? NamespaceString(ns) : NamespaceString();
+
+    if (op == dbQuery) {
+        if (nsString.isCommand()) {
+            isCommand = true;
+            opwrite(m);
+        }
+        // TODO: remove this entire code path after 3.2. Refs SERVER-7775
+        else if (nsString.isSpecialCommand()) {
+            opwrite(m);
+
+            if (nsString.coll() == "$cmd.sys.inprog") {
+                receivedPseudoCommand(txn, c, dbresponse, m, "currentOp");
+                return;
+            }
+            if (nsString.coll() == "$cmd.sys.killop") {
+                receivedPseudoCommand(txn, c, dbresponse, m, "killOp");
+                return;
+            }
+            if (nsString.coll() == "$cmd.sys.unlock") {
+                receivedPseudoCommand(txn, c, dbresponse, m, "fsyncUnlock");
+                return;
+            }
+        } else {
+            opread(m);
+        }
+    } else if (op == dbGetMore) {
+        opread(m);
+    } else if (op == dbCommand) {
+        isCommand = true;
+        opwrite(m);
+    } else {
+        opwrite(m);
+    }
+
+    CurOp& currentOp = *CurOp::get(txn);
+    {
+        stdx::lock_guard<Client> lk(*txn->getClient());
+        // Commands handling code will reset this if the operation is a command
+        // which is logically a basic CRUD operation like query, insert, etc.
+        currentOp.setNetworkOp_inlock(op);
+        currentOp.setLogicalOp_inlock(networkOpToLogicalOp(op));
+    }
+
+    OpDebug& debug = currentOp.debug();
+
+    long long logThresholdMs = serverGlobalParams.slowMS;
+    bool shouldLogOpDebug = shouldLog(logger::LogSeverity::Debug(1));
+
+    if (op == dbQuery) {
+        if (isCommand) {
+            receivedCommand(txn, nsString, c, dbresponse, m);
+        } else {
+            receivedQuery(txn, nsString, c, dbresponse, m);
+        }
+    } else if (op == dbCommand) {
+        receivedRpc(txn, c, dbresponse, m);
+    } else if (op == dbGetMore) {
+        if (!receivedGetMore(txn, dbresponse, m, currentOp))
+            shouldLogOpDebug = true;
+    } else if (op == dbMsg) {
+        // deprecated - replaced by commands
+        const char* p = dbmsg.getns();
+
+        int len = strlen(p);
+        if (len > 400)
+            log() << curTimeMillis64() % 10000 << " long msg received, len:" << len;
+
+        if (strcmp("end", p) == 0)
+            dbresponse.response.setData(opReply, "dbMsg end no longer supported");
+        else
+            dbresponse.response.setData(opReply, "i am fine - dbMsg deprecated");
+
+        dbresponse.responseToMsgId = m.header().getId();
+    } else {
+        // The remaining operations do not return any response. They are fire-and-forget.
+        try {
+            if (op == dbKillCursors) {
+                currentOp.ensureStarted();
+                logThresholdMs = 10;
+                receivedKillCursors(txn, m);
+            } else if (op != dbInsert && op != dbUpdate && op != dbDelete) {
+                log() << "    operation isn't supported: " << static_cast<int>(op);
+                currentOp.done();
+                shouldLogOpDebug = true;
+            } else {
+                if (remote != kHostAndPortForDirectClient) {
+                    const ShardedConnectionInfo* connInfo = ShardedConnectionInfo::get(&c, false);
+                    uassert(18663,
+                            str::stream() << "legacy writeOps not longer supported for "
+                                          << "versioned connections, ns: "
+                                          << nsString.ns()
+                                          << ", op: "
+                                          << networkOpToString(op)
+                                          << ", remote: "
+                                          << remote.toString(),
+                            connInfo == NULL);
+                }
+
+                if (!nsString.isValid()) {
+                    uassert(16257, str::stream() << "Invalid ns [" << ns << "]", false);
+                } else if (op == dbInsert) {
+                    receivedInsert(txn, nsString, m);
+                } else if (op == dbUpdate) {
+                    receivedUpdate(txn, nsString, m);
+                } else if (op == dbDelete) {
+                    receivedDelete(txn, nsString, m);
+                } else {
+                    invariant(false);
+                }
+            }
+        } catch (const UserException& ue) {
+            LastError::get(c).setLastError(ue.getCode(), ue.getInfo().msg);
+            LOG(3) << " Caught Assertion in " << networkOpToString(op) << ", continuing "
+                   << redact(ue);
+            debug.exceptionInfo = ue.getInfo();
+        } catch (const AssertionException& e) {
+            LastError::get(c).setLastError(e.getCode(), e.getInfo().msg);
+            LOG(3) << " Caught Assertion in " << networkOpToString(op) << ", continuing "
+                   << redact(e);
+            debug.exceptionInfo = e.getInfo();
+            shouldLogOpDebug = true;
+        }
+    }
+    currentOp.ensureStarted();
+    currentOp.done();
+    debug.executionTimeMicros = currentOp.totalTimeMicros();
+
+    logThresholdMs += currentOp.getExpectedLatencyMs();
+    Top::get(txn->getServiceContext())
+        .incrementGlobalLatencyStats(
+            txn, currentOp.totalTimeMicros(), currentOp.getReadWriteType());
+
+    if (shouldLogOpDebug || debug.executionTimeMicros > logThresholdMs * 1000LL) {
+        Locker::LockerInfo lockerInfo;
+        txn->lockState()->getLockerInfo(&lockerInfo);
+        log() << debug.report(&c, currentOp, lockerInfo.stats);
+    }
+
+    if (currentOp.shouldDBProfile()) {
+        // Performance profiling is on
+        if (txn->lockState()->isReadLocked()) {
+            LOG(1) << "note: not profiling because recursive read lock";
+        } else if (lockedForWriting()) {
+            // TODO SERVER-26825: Fix race condition where fsyncLock is acquired post
+            // lockedForWriting() call but prior to profile collection lock acquisition.
+            LOG(1) << "note: not profiling because doing fsync+lock";
+        } else if (storageGlobalParams.readOnly) {
+            LOG(1) << "note: not profiling because server is read-only";
+        } else {
+            profile(txn, op);
+        }
+    }
+
+    recordCurOpMetrics(txn);
+}
+
+}  // namespace mongo
diff --git a/src/mongo/db/assemble_response.h b/src/mongo/db/assemble_response.h
new file mode 100644
index 00000000000..c8c71fd9aad
--- /dev/null
+++ b/src/mongo/db/assemble_response.h
@@ -0,0 +1,48 @@
+/**
+*    Copyright (C) 2008 10gen Inc.
+*
+*    This program is free software: you can redistribute it and/or  modify
+*    it under the terms of the GNU Affero General Public License, version 3,
+*    as published by the Free Software Foundation.
+*
+*    This program is distributed in the hope that it will be useful,
+*    but WITHOUT ANY WARRANTY; without even the implied warranty of
+*    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+*    GNU Affero General Public License for more details.
+*
+*    You should have received a copy of the GNU Affero General Public License
+*    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*
+*    As a special exception, the copyright holders give permission to link the
+*    code of portions of this program with the OpenSSL library under certain
+*    conditions as described in each individual source file and distribute
+*    linked combinations including the program with the OpenSSL library. You
+*    must comply with the GNU Affero General Public License in all respects for
+*    all of the code used other than as permitted herein. If you modify file(s)
+*    with this exception, you may extend this exception to your version of the
+*    file(s), but you are not obligated to do so. If you do not wish to do so,
+*    delete this exception statement from your version. If you delete this
+*    exception statement from all source files in the program, then also delete
+*    it in the license file.
+*/
+
+#pragma once
+
+#include "mongo/util/net/hostandport.h"
+
+namespace mongo {
+
+struct DbResponse;
+class Message;
+class OperationContext;
+
+// Pass this as the 'client' argument to assembleResponse
+// to indicate that the call is on behalf of a DBDirectClient.
+extern const HostAndPort kHostAndPortForDirectClient;
+
+void assembleResponse(OperationContext* txn,
+                      Message& m,
+                      DbResponse& dbresponse,
+                      const HostAndPort& client);
+
+}  // namespace mongo
diff --git a/src/mongo/db/auth/authz_session_external_state_d.cpp b/src/mongo/db/auth/authz_session_external_state_d.cpp
index dee99046240..25298b2823b 100644
--- a/src/mongo/db/auth/authz_session_external_state_d.cpp
+++ b/src/mongo/db/auth/authz_session_external_state_d.cpp
@@ -33,7 +33,6 @@
 #include "mongo/db/auth/authorization_manager.h"
 #include "mongo/db/client.h"
 #include "mongo/db/dbhelpers.h"
-#include "mongo/db/instance.h"
 #include "mongo/db/jsobj.h"
 #include "mongo/db/operation_context.h"
 #include "mongo/db/repl/replication_coordinator_global.h"
diff --git a/src/mongo/db/catalog/database.cpp b/src/mongo/db/catalog/database.cpp
index 7361e1f4f4c..5d4ff27c56e 100644
--- a/src/mongo/db/catalog/database.cpp
+++ b/src/mongo/db/catalog/database.cpp
@@ -50,7 +50,6 @@
 #include "mongo/db/concurrency/write_conflict_exception.h"
 #include "mongo/db/dbhelpers.h"
 #include "mongo/db/index/index_access_method.h"
-#include "mongo/db/instance.h"
 #include "mongo/db/introspect.h"
 #include "mongo/db/op_observer.h"
 #include "mongo/db/query/collation/collator_factory_interface.h"
diff --git a/src/mongo/db/commands/clone_collection.cpp b/src/mongo/db/commands/clone_collection.cpp
index a7cf1e04017..512c9d7b737 100644
--- a/src/mongo/db/commands/clone_collection.cpp
+++ b/src/mongo/db/commands/clone_collection.cpp
@@ -45,7 +45,6 @@
 #include "mongo/db/commands/rename_collection.h"
 #include "mongo/db/db.h"
 #include "mongo/db/index_builder.h"
-#include "mongo/db/instance.h"
 #include "mongo/db/jsobj.h"
 #include "mongo/db/namespace_string.h"
 #include "mongo/db/ops/insert.h"
diff --git a/src/mongo/db/commands/dbcommands.cpp b/src/mongo/db/commands/dbcommands.cpp
index 9aeaa83a3e9..a7bfbc9d351 100644
--- a/src/mongo/db/commands/dbcommands.cpp
+++ b/src/mongo/db/commands/dbcommands.cpp
@@ -69,7 +69,6 @@
 #include "mongo/db/index/index_access_method.h"
 #include "mongo/db/index/index_descriptor.h"
 #include "mongo/db/index_builder.h"
-#include "mongo/db/instance.h"
 #include "mongo/db/introspect.h"
 #include "mongo/db/jsobj.h"
 #include "mongo/db/json.h"
diff --git a/src/mongo/db/commands/distinct.cpp b/src/mongo/db/commands/distinct.cpp
index 2543e4879bc..1b129780fa7 100644
--- a/src/mongo/db/commands/distinct.cpp
+++ b/src/mongo/db/commands/distinct.cpp
@@ -47,7 +47,6 @@
 #include "mongo/db/commands.h"
 #include "mongo/db/db_raii.h"
 #include "mongo/db/exec/working_set_common.h"
-#include "mongo/db/instance.h"
 #include "mongo/db/jsobj.h"
 #include "mongo/db/matcher/extensions_callback_real.h"
 #include "mongo/db/query/cursor_response.h"
diff --git a/src/mongo/db/commands/generic.cpp b/src/mongo/db/commands/generic.cpp
index ae173c44942..57e96ac75c7 100644
--- a/src/mongo/db/commands/generic.cpp
+++ b/src/mongo/db/commands/generic.cpp
@@ -42,7 +42,6 @@
 #include "mongo/db/commands.h"
 #include "mongo/db/commands/shutdown.h"
 #include "mongo/db/db.h"
-#include "mongo/db/instance.h"
 #include "mongo/db/introspect.h"
 #include "mongo/db/jsobj.h"
 #include "mongo/db/json.h"
diff --git a/src/mongo/db/commands/mr.cpp b/src/mongo/db/commands/mr.cpp
index 093ffefa1db..fd45c5dd115 100644
--- a/src/mongo/db/commands/mr.cpp
+++ b/src/mongo/db/commands/mr.cpp
@@ -51,7 +51,6 @@
 #include "mongo/db/dbhelpers.h"
 #include "mongo/db/exec/working_set_common.h"
 #include "mongo/db/index/index_descriptor.h"
-#include "mongo/db/instance.h"
 #include "mongo/db/matcher/extensions_callback_real.h"
 #include "mongo/db/matcher/matcher.h"
 #include "mongo/db/namespace_string.h"
diff --git a/src/mongo/db/dbdirectclient.cpp b/src/mongo/db/dbdirectclient.cpp
index f4bf62ed644..40fcdb79dc2 100644
--- a/src/mongo/db/dbdirectclient.cpp
+++ b/src/mongo/db/dbdirectclient.cpp
@@ -32,9 +32,10 @@
 
 #include "mongo/db/dbdirectclient.h"
 
+#include "mongo/db/assemble_response.h"
 #include "mongo/db/client.h"
 #include "mongo/db/commands.h"
-#include "mongo/db/instance.h"
+#include "mongo/db/curop.h"
 #include "mongo/db/lasterror.h"
 #include "mongo/db/operation_context.h"
 #include "mongo/db/wire_version.h"
@@ -124,7 +125,7 @@ bool DBDirectClient::call(Message& toSend, Message& response, bool assertOk, str
 
     DbResponse dbResponse;
     CurOp curOp(_txn);
-    assembleResponse(_txn, toSend, dbResponse, dummyHost);
+    assembleResponse(_txn, toSend, dbResponse, kHostAndPortForDirectClient);
     verify(!dbResponse.response.empty());
     response = std::move(dbResponse.response);
 
@@ -137,7 +138,7 @@ void DBDirectClient::say(Message& toSend, bool isRetry, string* actualServer) {
 
     DbResponse dbResponse;
     CurOp curOp(_txn);
-    assembleResponse(_txn, toSend, dbResponse, dummyHost);
+    assembleResponse(_txn, toSend, dbResponse, kHostAndPortForDirectClient);
 }
 
 unique_ptr<DBClientCursor> DBDirectClient::query(const string& ns,
@@ -151,8 +152,6 @@ unique_ptr<DBClientCursor> DBDirectClient::query(const string& ns,
         ns, query, nToReturn, nToSkip, fieldsToReturn, queryOptions, batchSize);
 }
 
-const HostAndPort DBDirectClient::dummyHost("0.0.0.0", 0);
-
 unsigned long long DBDirectClient::count(
     const string& ns, const BSONObj& query, int options, int limit, int skip) {
     BSONObj cmdObj = _countCmd(ns, query, options, limit, skip);
diff --git a/src/mongo/db/dbdirectclient.h b/src/mongo/db/dbdirectclient.h
index d4d187ff91c..1bd4c407f8a 100644
--- a/src/mongo/db/dbdirectclient.h
+++ b/src/mongo/db/dbdirectclient.h
@@ -49,8 +49,6 @@ class OperationContext;
  */
 class DBDirectClient : public DBClientBase {
 public:
-    static const HostAndPort dummyHost;
-
     DBDirectClient(OperationContext* txn);
 
     using DBClientBase::query;
diff --git a/src/mongo/db/dbwebserver.cpp b/src/mongo/db/dbwebserver.cpp
index b202e0500b9..41b097c5718 100644
--- a/src/mongo/db/dbwebserver.cpp
+++ b/src/mongo/db/dbwebserver.cpp
@@ -47,7 +47,6 @@
 #include "mongo/db/background.h"
 #include "mongo/db/commands.h"
 #include "mongo/db/db.h"
-#include "mongo/db/instance.h"
 #include "mongo/db/operation_context.h"
 #include "mongo/db/service_context.h"
 #include "mongo/db/stats/snapshots.h"
diff --git a/src/mongo/db/index_rebuilder.cpp b/src/mongo/db/index_rebuilder.cpp
index 2d4c40f5747..c42cbc1dcee 100644
--- a/src/mongo/db/index_rebuilder.cpp
+++ b/src/mongo/db/index_rebuilder.cpp
@@ -43,7 +43,6 @@
 #include "mongo/db/catalog/index_create.h"
 #include "mongo/db/client.h"
 #include "mongo/db/db_raii.h"
-#include "mongo/db/instance.h"
 #include "mongo/db/service_context.h"
 #include "mongo/db/storage/storage_engine.h"
 #include "mongo/util/log.h"
diff --git a/src/mongo/db/instance.cpp b/src/mongo/db/instance.cpp
index 367709954f0..10283a3d972 100644
--- a/src/mongo/db/instance.cpp
+++ b/src/mongo/db/instance.cpp
@@ -30,103 +30,23 @@
 
 #include "mongo/platform/basic.h"
 
-#include <fstream>
+#include "mongo/db/instance.h"
+
 #include <memory>
 
 #include "mongo/base/init.h"
-#include "mongo/base/status.h"
-#include "mongo/db/audit.h"
-#include "mongo/db/auth/action_type.h"
-#include "mongo/db/auth/authorization_manager.h"
-#include "mongo/db/auth/authorization_session.h"
 #include "mongo/db/auth/authz_manager_external_state_d.h"
-#include "mongo/db/catalog/cursor_manager.h"
-#include "mongo/db/client.h"
-#include "mongo/db/commands.h"
-#include "mongo/db/commands/fsync.h"
-#include "mongo/db/concurrency/d_concurrency.h"
-#include "mongo/db/concurrency/lock_state.h"
-#include "mongo/db/concurrency/write_conflict_exception.h"
-#include "mongo/db/curop_metrics.h"
-#include "mongo/db/db.h"
-#include "mongo/db/db_raii.h"
-#include "mongo/db/dbdirectclient.h"
-#include "mongo/db/dbmessage.h"
-#include "mongo/db/diag_log.h"
-#include "mongo/db/ftdc/ftdc_mongod.h"
-#include "mongo/db/global_timestamp.h"
-#include "mongo/db/instance.h"
-#include "mongo/db/introspect.h"
-#include "mongo/db/json.h"
-#include "mongo/db/lasterror.h"
-#include "mongo/db/matcher/matcher.h"
-#include "mongo/db/mongod_options.h"
-#include "mongo/db/namespace_string.h"
-#include "mongo/db/op_observer.h"
-#include "mongo/db/ops/write_ops_exec.h"
-#include "mongo/db/ops/write_ops_parsers.h"
-#include "mongo/db/query/find.h"
-#include "mongo/db/query/get_executor.h"
-#include "mongo/db/run_commands.h"
-#include "mongo/db/s/sharded_connection_info.h"
-#include "mongo/db/s/sharding_state.h"
-#include "mongo/db/service_context.h"
-#include "mongo/db/stats/counters.h"
-#include "mongo/db/stats/top.h"
-#include "mongo/db/storage/storage_engine.h"
-#include "mongo/db/storage/storage_options.h"
-#include "mongo/platform/atomic_word.h"
-#include "mongo/platform/process_id.h"
-#include "mongo/rpc/command_reply_builder.h"
-#include "mongo/rpc/command_request.h"
-#include "mongo/rpc/legacy_reply.h"
-#include "mongo/rpc/legacy_reply_builder.h"
-#include "mongo/rpc/legacy_request.h"
-#include "mongo/rpc/legacy_request_builder.h"
-#include "mongo/rpc/metadata.h"
-#include "mongo/rpc/request_interface.h"
-#include "mongo/s/stale_exception.h"  // for SendStaleConfigException
-#include "mongo/scripting/engine.h"
 #include "mongo/stdx/memory.h"
-#include "mongo/stdx/thread.h"
-#include "mongo/util/exit.h"
-#include "mongo/util/fail_point_service.h"
 #include "mongo/util/log.h"
-#include "mongo/util/mongoutils/str.h"
-#include "mongo/util/quick_exit.h"
-#include "mongo/util/scopeguard.h"
-#include "mongo/util/time_support.h"
 
 namespace mongo {
-using logger::LogComponent;
-using std::endl;
-using std::hex;
-using std::ios;
-using std::ofstream;
 using std::string;
-using std::stringstream;
 using std::unique_ptr;
-using std::vector;
 
 string dbExecCommand;
 
-MONGO_FP_DECLARE(rsStopGetMore);
-
 namespace {
 
-// for diaglog
-inline void opread(Message& m) {
-    if (_diaglog.getLevel() & 2) {
-        _diaglog.readop(m.singleData().view2ptr(), m.header().getLen());
-    }
-}
-
-inline void opwrite(Message& m) {
-    if (_diaglog.getLevel() & 1) {
-        _diaglog.writeop(m.singleData().view2ptr(), m.header().getLen());
-    }
-}
-
 unique_ptr<AuthzManagerExternalState> createAuthzManagerExternalStateMongod() {
     return stdx::make_unique<AuthzManagerExternalStateMongod>();
 }
@@ -136,395 +56,6 @@ MONGO_INITIALIZER(CreateAuthorizationExternalStateFactory)(InitializerContext* c
     return Status::OK();
 }
 
-void generateLegacyQueryErrorResponse(const AssertionException* exception,
-                                      const QueryMessage& queryMessage,
-                                      CurOp* curop,
-                                      Message* response) {
-    curop->debug().exceptionInfo = exception->getInfo();
-
-    log(LogComponent::kQuery) << "assertion " << exception->toString() << " ns:" << queryMessage.ns
-                              << " query:" << (queryMessage.query.valid(BSONVersion::kLatest)
-                                                   ? queryMessage.query.toString()
-                                                   : "query object is corrupt");
-    if (queryMessage.ntoskip || queryMessage.ntoreturn) {
-        log(LogComponent::kQuery) << " ntoskip:" << queryMessage.ntoskip
-                                  << " ntoreturn:" << queryMessage.ntoreturn;
-    }
-
-    const SendStaleConfigException* scex = (exception->getCode() == ErrorCodes::SendStaleConfig)
-        ? static_cast<const SendStaleConfigException*>(exception)
-        : NULL;
-
-    BSONObjBuilder err;
-    exception->getInfo().append(err);
-    if (scex) {
-        err.append("ok", 0.0);
-        err.append("ns", scex->getns());
-        scex->getVersionReceived().addToBSON(err, "vReceived");
-        scex->getVersionWanted().addToBSON(err, "vWanted");
-    }
-    BSONObj errObj = err.done();
-
-    if (scex) {
-        log(LogComponent::kQuery) << "stale version detected during query over " << queryMessage.ns
-                                  << " : " << errObj;
-    }
-
-    BufBuilder bb;
-    bb.skip(sizeof(QueryResult::Value));
-    bb.appendBuf((void*)errObj.objdata(), errObj.objsize());
-
-    // TODO: call replyToQuery() from here instead of this!!! see dbmessage.h
-    QueryResult::View msgdata = bb.buf();
-    QueryResult::View qr = msgdata;
-    qr.setResultFlags(ResultFlag_ErrSet);
-    if (scex)
-        qr.setResultFlags(qr.getResultFlags() | ResultFlag_ShardConfigStale);
-    qr.msgdata().setLen(bb.len());
-    qr.msgdata().setOperation(opReply);
-    qr.setCursorId(0);
-    qr.setStartingFrom(0);
-    qr.setNReturned(1);
-    response->setData(bb.release());
-}
-
-/**
- * Fills out CurOp / OpDebug with basic command info.
- */
-void beginCommandOp(OperationContext* txn, const NamespaceString& nss, const BSONObj& queryObj) {
-    auto curop = CurOp::get(txn);
-    stdx::lock_guard<Client> lk(*txn->getClient());
-    curop->setQuery_inlock(queryObj);
-    curop->setNS_inlock(nss.ns());
-}
-
-void receivedCommand(OperationContext* txn,
-                     const NamespaceString& nss,
-                     Client& client,
-                     DbResponse& dbResponse,
-                     Message& message) {
-    invariant(nss.isCommand());
-
-    const int32_t responseToMsgId = message.header().getId();
-
-    DbMessage dbMessage(message);
-    QueryMessage queryMessage(dbMessage);
-
-    CurOp* op = CurOp::get(txn);
-
-    rpc::LegacyReplyBuilder builder{};
-
-    try {
-        // This will throw if the request is on an invalid namespace.
-        rpc::LegacyRequest request{&message};
-        // Auth checking for Commands happens later.
-        int nToReturn = queryMessage.ntoreturn;
-
-        beginCommandOp(txn, nss, request.getCommandArgs());
-
-        {
-            stdx::lock_guard<Client> lk(*txn->getClient());
-            op->markCommand_inlock();
-        }
-
-        uassert(16979,
-                str::stream() << "bad numberToReturn (" << nToReturn
-                              << ") for $cmd type ns - can only be 1 or -1",
-                nToReturn == 1 || nToReturn == -1);
-
-        runCommands(txn, request, &builder);
-
-        op->debug().iscommand = true;
-    } catch (const DBException& exception) {
-        Command::generateErrorResponse(txn, &builder, exception);
-    }
-
-    auto response = builder.done();
-
-    op->debug().responseLength = response.header().dataLen();
-
-    dbResponse.response = std::move(response);
-    dbResponse.responseToMsgId = responseToMsgId;
-}
-
-void receivedRpc(OperationContext* txn, Client& client, DbResponse& dbResponse, Message& message) {
-    invariant(message.operation() == dbCommand);
-
-    const int32_t responseToMsgId = message.header().getId();
-
-    rpc::CommandReplyBuilder replyBuilder{};
-
-    auto curOp = CurOp::get(txn);
-
-    try {
-        // database is validated here
-        rpc::CommandRequest request{&message};
-
-        // We construct a legacy $cmd namespace so we can fill in curOp using
-        // the existing logic that existed for OP_QUERY commands
-        NamespaceString nss(request.getDatabase(), "$cmd");
-        beginCommandOp(txn, nss, request.getCommandArgs());
-        {
-            stdx::lock_guard<Client> lk(*txn->getClient());
-            curOp->markCommand_inlock();
-        }
-
-        runCommands(txn, request, &replyBuilder);
-
-        curOp->debug().iscommand = true;
-
-    } catch (const DBException& exception) {
-        Command::generateErrorResponse(txn, &replyBuilder, exception);
-    }
-
-    auto response = replyBuilder.done();
-
-    curOp->debug().responseLength = response.header().dataLen();
-
-    dbResponse.response = std::move(response);
-    dbResponse.responseToMsgId = responseToMsgId;
-}
-
-// In SERVER-7775 we reimplemented the pseudo-commands fsyncUnlock, inProg, and killOp
-// as ordinary commands. To support old clients for another release, this helper serves
-// to execute the real command from the legacy pseudo-command codepath.
-// TODO: remove after MongoDB 3.2 is released
-void receivedPseudoCommand(OperationContext* txn,
-                           Client& client,
-                           DbResponse& dbResponse,
-                           Message& message,
-                           StringData realCommandName) {
-    DbMessage originalDbm(message);
-
-    auto originalNToSkip = originalDbm.pullInt();
-
-    uassert(ErrorCodes::InvalidOptions,
-            str::stream() << "invalid nToSkip - expected 0, but got " << originalNToSkip,
-            originalNToSkip == 0);
-
-    auto originalNToReturn = originalDbm.pullInt();
-
-    uassert(ErrorCodes::InvalidOptions,
-            str::stream() << "invalid nToReturn - expected -1 or 1, but got " << originalNToSkip,
-            originalNToReturn == -1 || originalNToReturn == 1);
-
-    auto cmdParams = originalDbm.nextJsObj();
-
-    Message interposed;
-    // HACK:
-    // legacy pseudo-commands could run on any database. The command replacements
-    // can only run on 'admin'. To avoid breaking old shells and a multitude
-    // of third-party tools, we rewrite the namespace. As auth is checked
-    // later in Command::_checkAuthorizationImpl, we will still properly
-    // reject the request if the client is not authorized.
-    NamespaceString interposedNss("admin", "$cmd");
-
-    BSONObjBuilder cmdBob;
-    cmdBob.append(realCommandName, 1);
-    cmdBob.appendElements(cmdParams);
-    auto cmd = cmdBob.done();
-
-    // TODO: use OP_COMMAND here instead of constructing
-    // a legacy OP_QUERY style command
-    BufBuilder cmdMsgBuf;
-
-    int32_t flags = DataView(message.header().data()).read<LittleEndian<int32_t>>();
-    cmdMsgBuf.appendNum(flags);
-
-    cmdMsgBuf.appendStr(interposedNss.db(), false);  // not including null byte
-    cmdMsgBuf.appendStr(".$cmd");
-    cmdMsgBuf.appendNum(0);  // ntoskip
-    cmdMsgBuf.appendNum(1);  // ntoreturn
-    cmdMsgBuf.appendBuf(cmd.objdata(), cmd.objsize());
-
-    interposed.setData(dbQuery, cmdMsgBuf.buf(), cmdMsgBuf.len());
-    interposed.header().setId(message.header().getId());
-
-    receivedCommand(txn, interposedNss, client, dbResponse, interposed);
-}
-
-void receivedQuery(OperationContext* txn,
-                   const NamespaceString& nss,
-                   Client& c,
-                   DbResponse& dbResponse,
-                   Message& m) {
-    invariant(!nss.isCommand());
-    globalOpCounters.gotQuery();
-
-    int32_t responseToMsgId = m.header().getId();
-
-    DbMessage d(m);
-    QueryMessage q(d);
-
-    CurOp& op = *CurOp::get(txn);
-
-    try {
-        Client* client = txn->getClient();
-        Status status = AuthorizationSession::get(client)->checkAuthForFind(nss, false);
-        audit::logQueryAuthzCheck(client, nss, q.query, status.code());
-        uassertStatusOK(status);
-
-        dbResponse.exhaustNS = runQuery(txn, q, nss, dbResponse.response);
-    } catch (const AssertionException& e) {
-        // If we got a stale config, wait in case the operation is stuck in a critical section
-        if (e.getCode() == ErrorCodes::SendStaleConfig) {
-            auto& sce = static_cast<const StaleConfigException&>(e);
-            ShardingState::get(txn)->onStaleShardVersion(
-                txn, NamespaceString(sce.getns()), sce.getVersionReceived());
-        }
-
-        dbResponse.response.reset();
-        generateLegacyQueryErrorResponse(&e, q, &op, &dbResponse.response);
-    }
-
-    op.debug().responseLength = dbResponse.response.header().dataLen();
-    dbResponse.responseToMsgId = responseToMsgId;
-}
-
-void receivedKillCursors(OperationContext* txn, Message& m) {
-    LastError::get(txn->getClient()).disable();
-    DbMessage dbmessage(m);
-    int n = dbmessage.pullInt();
-
-    uassert(13659, "sent 0 cursors to kill", n != 0);
-    massert(13658,
-            str::stream() << "bad kill cursors size: " << m.dataSize(),
-            m.dataSize() == 8 + (8 * n));
-    uassert(13004, str::stream() << "sent negative cursors to kill: " << n, n >= 1);
-
-    if (n > 2000) {
-        (n < 30000 ? warning() : error()) << "receivedKillCursors, n=" << n;
-        verify(n < 30000);
-    }
-
-    const char* cursorArray = dbmessage.getArray(n);
-
-    int found = CursorManager::eraseCursorGlobalIfAuthorized(txn, n, cursorArray);
-
-    if (shouldLog(logger::LogSeverity::Debug(1)) || found != n) {
-        LOG(found == n ? 1 : 0) << "killcursors: found " << found << " of " << n;
-    }
-}
-
-void receivedInsert(OperationContext* txn, const NamespaceString& nsString, Message& m) {
-    auto insertOp = parseLegacyInsert(m);
-    invariant(insertOp.ns == nsString);
-    for (const auto& obj : insertOp.documents) {
-        Status status =
-            AuthorizationSession::get(txn->getClient())->checkAuthForInsert(txn, nsString, obj);
-        audit::logInsertAuthzCheck(txn->getClient(), nsString, obj, status.code());
-        uassertStatusOK(status);
-    }
-    performInserts(txn, insertOp);
-}
-
-void receivedUpdate(OperationContext* txn, const NamespaceString& nsString, Message& m) {
-    auto updateOp = parseLegacyUpdate(m);
-    auto& singleUpdate = updateOp.updates[0];
-    invariant(updateOp.ns == nsString);
-
-    Status status =
-        AuthorizationSession::get(txn->getClient())
-            ->checkAuthForUpdate(
-                txn, nsString, singleUpdate.query, singleUpdate.update, singleUpdate.upsert);
-    audit::logUpdateAuthzCheck(txn->getClient(),
-                               nsString,
-                               singleUpdate.query,
-                               singleUpdate.update,
-                               singleUpdate.upsert,
-                               singleUpdate.multi,
-                               status.code());
-    uassertStatusOK(status);
-
-    performUpdates(txn, updateOp);
-}
-
-void receivedDelete(OperationContext* txn, const NamespaceString& nsString, Message& m) {
-    auto deleteOp = parseLegacyDelete(m);
-    auto& singleDelete = deleteOp.deletes[0];
-    invariant(deleteOp.ns == nsString);
-
-    Status status = AuthorizationSession::get(txn->getClient())
-                        ->checkAuthForDelete(txn, nsString, singleDelete.query);
-    audit::logDeleteAuthzCheck(txn->getClient(), nsString, singleDelete.query, status.code());
-    uassertStatusOK(status);
-
-    performDeletes(txn, deleteOp);
-}
-
-bool receivedGetMore(OperationContext* txn, DbResponse& dbresponse, Message& m, CurOp& curop) {
-    globalOpCounters.gotGetMore();
-    DbMessage d(m);
-
-    const char* ns = d.getns();
-    int ntoreturn = d.pullInt();
-    uassert(
-        34419, str::stream() << "Invalid ntoreturn for OP_GET_MORE: " << ntoreturn, ntoreturn >= 0);
-    long long cursorid = d.pullInt64();
-
-    curop.debug().ntoreturn = ntoreturn;
-    curop.debug().cursorid = cursorid;
-
-    {
-        stdx::lock_guard<Client>(*txn->getClient());
-        CurOp::get(txn)->setNS_inlock(ns);
-    }
-
-    bool exhaust = false;
-    bool isCursorAuthorized = false;
-
-    try {
-        const NamespaceString nsString(ns);
-        uassert(ErrorCodes::InvalidNamespace,
-                str::stream() << "Invalid ns [" << ns << "]",
-                nsString.isValid());
-
-        Status status = AuthorizationSession::get(txn->getClient())
-                            ->checkAuthForGetMore(nsString, cursorid, false);
-        audit::logGetMoreAuthzCheck(txn->getClient(), nsString, cursorid, status.code());
-        uassertStatusOK(status);
-
-        while (MONGO_FAIL_POINT(rsStopGetMore)) {
-            sleepmillis(0);
-        }
-
-        dbresponse.response = getMore(txn, ns, ntoreturn, cursorid, &exhaust, &isCursorAuthorized);
-    } catch (AssertionException& e) {
-        if (isCursorAuthorized) {
-            // If a cursor with id 'cursorid' was authorized, it may have been advanced
-            // before an exception terminated processGetMore.  Erase the ClientCursor
-            // because it may now be out of sync with the client's iteration state.
-            // SERVER-7952
-            // TODO Temporary code, see SERVER-4563 for a cleanup overview.
-            CursorManager::eraseCursorGlobal(txn, cursorid);
-        }
-
-        BSONObjBuilder err;
-        e.getInfo().append(err);
-        BSONObj errObj = err.done();
-
-        curop.debug().exceptionInfo = e.getInfo();
-
-        replyToQuery(ResultFlag_ErrSet, m, dbresponse, errObj);
-        curop.debug().responseLength = dbresponse.response.header().dataLen();
-        curop.debug().nreturned = 1;
-        return false;
-    }
-
-    curop.debug().responseLength = dbresponse.response.header().dataLen();
-    auto queryResult = QueryResult::ConstView(dbresponse.response.buf());
-    curop.debug().nreturned = queryResult.getNReturned();
-
-    dbresponse.responseToMsgId = m.header().getId();
-
-    if (exhaust) {
-        curop.debug().exhaust = true;
-        dbresponse.exhaustNS = ns;
-    }
-
-    return true;
-}
-
 }  // namespace
 
 // Mongod on win32 defines a value for this function. In all other executables it is NULL.
@@ -537,184 +68,4 @@ void mongoAbort(const char* msg) {
     ::abort();
 }
 
-// Returns false when request includes 'end'
-void assembleResponse(OperationContext* txn,
-                      Message& m,
-                      DbResponse& dbresponse,
-                      const HostAndPort& remote) {
-    // before we lock...
-    NetworkOp op = m.operation();
-    bool isCommand = false;
-
-    DbMessage dbmsg(m);
-
-    Client& c = *txn->getClient();
-    if (c.isInDirectClient()) {
-        invariant(!txn->lockState()->inAWriteUnitOfWork());
-    } else {
-        LastError::get(c).startRequest();
-        AuthorizationSession::get(c)->startRequest(txn);
-
-        // We should not be holding any locks at this point
-        invariant(!txn->lockState()->isLocked());
-    }
-
-    const char* ns = dbmsg.messageShouldHaveNs() ? dbmsg.getns() : NULL;
-    const NamespaceString nsString = ns ? NamespaceString(ns) : NamespaceString();
-
-    if (op == dbQuery) {
-        if (nsString.isCommand()) {
-            isCommand = true;
-            opwrite(m);
-        }
-        // TODO: remove this entire code path after 3.2. Refs SERVER-7775
-        else if (nsString.isSpecialCommand()) {
-            opwrite(m);
-
-            if (nsString.coll() == "$cmd.sys.inprog") {
-                receivedPseudoCommand(txn, c, dbresponse, m, "currentOp");
-                return;
-            }
-            if (nsString.coll() == "$cmd.sys.killop") {
-                receivedPseudoCommand(txn, c, dbresponse, m, "killOp");
-                return;
-            }
-            if (nsString.coll() == "$cmd.sys.unlock") {
-                receivedPseudoCommand(txn, c, dbresponse, m, "fsyncUnlock");
-                return;
-            }
-        } else {
-            opread(m);
-        }
-    } else if (op == dbGetMore) {
-        opread(m);
-    } else if (op == dbCommand) {
-        isCommand = true;
-        opwrite(m);
-    } else {
-        opwrite(m);
-    }
-
-    CurOp& currentOp = *CurOp::get(txn);
-    {
-        stdx::lock_guard<Client> lk(*txn->getClient());
-        // Commands handling code will reset this if the operation is a command
-        // which is logically a basic CRUD operation like query, insert, etc.
-        currentOp.setNetworkOp_inlock(op);
-        currentOp.setLogicalOp_inlock(networkOpToLogicalOp(op));
-    }
-
-    OpDebug& debug = currentOp.debug();
-
-    long long logThresholdMs = serverGlobalParams.slowMS;
-    bool shouldLogOpDebug = shouldLog(logger::LogSeverity::Debug(1));
-
-    if (op == dbQuery) {
-        if (isCommand) {
-            receivedCommand(txn, nsString, c, dbresponse, m);
-        } else {
-            receivedQuery(txn, nsString, c, dbresponse, m);
-        }
-    } else if (op == dbCommand) {
-        receivedRpc(txn, c, dbresponse, m);
-    } else if (op == dbGetMore) {
-        if (!receivedGetMore(txn, dbresponse, m, currentOp))
-            shouldLogOpDebug = true;
-    } else if (op == dbMsg) {
-        // deprecated - replaced by commands
-        const char* p = dbmsg.getns();
-
-        int len = strlen(p);
-        if (len > 400)
-            log() << curTimeMillis64() % 10000 << " long msg received, len:" << len;
-
-        if (strcmp("end", p) == 0)
-            dbresponse.response.setData(opReply, "dbMsg end no longer supported");
-        else
-            dbresponse.response.setData(opReply, "i am fine - dbMsg deprecated");
-
-        dbresponse.responseToMsgId = m.header().getId();
-    } else {
-        // The remaining operations do not return any response. They are fire-and-forget.
-        try {
-            if (op == dbKillCursors) {
-                currentOp.ensureStarted();
-                logThresholdMs = 10;
-                receivedKillCursors(txn, m);
-            } else if (op != dbInsert && op != dbUpdate && op != dbDelete) {
-                log() << "    operation isn't supported: " << static_cast<int>(op);
-                currentOp.done();
-                shouldLogOpDebug = true;
-            } else {
-                if (remote != DBDirectClient::dummyHost) {
-                    const ShardedConnectionInfo* connInfo = ShardedConnectionInfo::get(&c, false);
-                    uassert(18663,
-                            str::stream() << "legacy writeOps not longer supported for "
-                                          << "versioned connections, ns: "
-                                          << nsString.ns()
-                                          << ", op: "
-                                          << networkOpToString(op)
-                                          << ", remote: "
-                                          << remote.toString(),
-                            connInfo == NULL);
-                }
-
-                if (!nsString.isValid()) {
-                    uassert(16257, str::stream() << "Invalid ns [" << ns << "]", false);
-                } else if (op == dbInsert) {
-                    receivedInsert(txn, nsString, m);
-                } else if (op == dbUpdate) {
-                    receivedUpdate(txn, nsString, m);
-                } else if (op == dbDelete) {
-                    receivedDelete(txn, nsString, m);
-                } else {
-                    invariant(false);
-                }
-            }
-        } catch (const UserException& ue) {
-            LastError::get(c).setLastError(ue.getCode(), ue.getInfo().msg);
-            LOG(3) << " Caught Assertion in " << networkOpToString(op) << ", continuing "
-                   << redact(ue);
-            debug.exceptionInfo = ue.getInfo();
-        } catch (const AssertionException& e) {
-            LastError::get(c).setLastError(e.getCode(), e.getInfo().msg);
-            LOG(3) << " Caught Assertion in " << networkOpToString(op) << ", continuing "
-                   << redact(e);
-            debug.exceptionInfo = e.getInfo();
-            shouldLogOpDebug = true;
-        }
-    }
-    currentOp.ensureStarted();
-    currentOp.done();
-    debug.executionTimeMicros = currentOp.totalTimeMicros();
-
-    logThresholdMs += currentOp.getExpectedLatencyMs();
-    Top::get(txn->getServiceContext())
-        .incrementGlobalLatencyStats(
-            txn, currentOp.totalTimeMicros(), currentOp.getReadWriteType());
-
-    if (shouldLogOpDebug || debug.executionTimeMicros > logThresholdMs * 1000LL) {
-        Locker::LockerInfo lockerInfo;
-        txn->lockState()->getLockerInfo(&lockerInfo);
-        log() << debug.report(&c, currentOp, lockerInfo.stats);
-    }
-
-    if (currentOp.shouldDBProfile()) {
-        // Performance profiling is on
-        if (txn->lockState()->isReadLocked()) {
-            LOG(1) << "note: not profiling because recursive read lock";
-        } else if (lockedForWriting()) {
-            // TODO SERVER-26825: Fix race condition where fsyncLock is acquired post
-            // lockedForWriting() call but prior to profile collection lock acquisition.
-            LOG(1) << "note: not profiling because doing fsync+lock";
-        } else if (storageGlobalParams.readOnly) {
-            LOG(1) << "note: not profiling because server is read-only";
-        } else {
-            profile(txn, op);
-        }
-    }
-
-    recordCurOpMetrics(txn);
-}
-
 }  // namespace mongo
diff --git a/src/mongo/db/instance.h b/src/mongo/db/instance.h
index 2d62bdabf20..764b4605432 100644
--- a/src/mongo/db/instance.h
+++ b/src/mongo/db/instance.h
@@ -31,21 +31,12 @@
 
 #pragma once
 
-#include "mongo/client/dbclientinterface.h"
-#include "mongo/db/curop.h"
-#include "mongo/db/dbmessage.h"
-#include "mongo/db/operation_context.h"
-#include "mongo/db/storage/storage_options.h"
+#include <string>
 
 namespace mongo {
 
 extern std::string dbExecCommand;
 
-void assembleResponse(OperationContext* txn,
-                      Message& m,
-                      DbResponse& dbresponse,
-                      const HostAndPort& client);
-
 void maybeCreatePidFile();
 
 }  // namespace mongo
diff --git a/src/mongo/db/mongod_options.cpp b/src/mongo/db/mongod_options.cpp
index d1c85db71d1..1c18fb819c5 100644
--- a/src/mongo/db/mongod_options.cpp
+++ b/src/mongo/db/mongod_options.cpp
@@ -41,7 +41,6 @@
 #include "mongo/config.h"
 #include "mongo/db/db.h"
 #include "mongo/db/diag_log.h"
-#include "mongo/db/instance.h"
 #include "mongo/db/repl/repl_settings.h"
 #include "mongo/db/server_options.h"
 #include "mongo/db/server_options_helpers.h"
diff --git a/src/mongo/db/pipeline/accumulator_test.cpp b/src/mongo/db/pipeline/accumulator_test.cpp
index d2ef7d7e445..c2619b3d31d 100644
--- a/src/mongo/db/pipeline/accumulator_test.cpp
+++ b/src/mongo/db/pipeline/accumulator_test.cpp
@@ -35,6 +35,7 @@
 #include "mongo/db/pipeline/expression_context.h"
 #include "mongo/db/query/collation/collator_interface_mock.h"
 #include "mongo/dbtests/dbtests.h"
+#include "mongo/stdx/memory.h"
 
 namespace AccumulatorTests {
 
diff --git a/src/mongo/db/pipeline/document_source_cursor.cpp b/src/mongo/db/pipeline/document_source_cursor.cpp
index 0936f6291fe..5c5be2aef1f 100644
--- a/src/mongo/db/pipeline/document_source_cursor.cpp
+++ b/src/mongo/db/pipeline/document_source_cursor.cpp
@@ -33,7 +33,6 @@
 #include "mongo/db/catalog/database_holder.h"
 #include "mongo/db/db_raii.h"
 #include "mongo/db/exec/working_set_common.h"
-#include "mongo/db/instance.h"
 #include "mongo/db/pipeline/document.h"
 #include "mongo/db/query/explain.h"
 #include "mongo/db/query/find_common.h"
diff --git a/src/mongo/db/pipeline/document_value_test.cpp b/src/mongo/db/pipeline/document_value_test.cpp
index c0182cb2fc4..8fe236cbcc2 100644
--- a/src/mongo/db/pipeline/document_value_test.cpp
+++ b/src/mongo/db/pipeline/document_value_test.cpp
@@ -30,6 +30,8 @@
 
 #include "mongo/platform/basic.h"
 
+#include "mongo/db/jsobj.h"
+#include "mongo/db/json.h"
 #include "mongo/db/pipeline/document.h"
 #include "mongo/db/pipeline/document_comparator.h"
 #include "mongo/db/pipeline/document_value_test_util.h"
diff --git a/src/mongo/db/pipeline/expression_test.cpp b/src/mongo/db/pipeline/expression_test.cpp
index bebbcf9ba50..48d7c1bc521 100644
--- a/src/mongo/db/pipeline/expression_test.cpp
+++ b/src/mongo/db/pipeline/expression_test.cpp
@@ -30,6 +30,8 @@
 
 #include "mongo/bson/bsonmisc.h"
 #include "mongo/config.h"
+#include "mongo/db/jsobj.h"
+#include "mongo/db/json.h"
 #include "mongo/db/pipeline/accumulator.h"
 #include "mongo/db/pipeline/document.h"
 #include "mongo/db/pipeline/document_value_test_util.h"
diff --git a/src/mongo/db/service_entry_point_mongod.cpp b/src/mongo/db/service_entry_point_mongod.cpp
index ac00e12d9ac..8d040d745ad 100644
--- a/src/mongo/db/service_entry_point_mongod.cpp
+++ b/src/mongo/db/service_entry_point_mongod.cpp
@@ -34,9 +34,9 @@
 
 #include <vector>
 
+#include "mongo/db/assemble_response.h"
 #include "mongo/db/client.h"
 #include "mongo/db/dbmessage.h"
-#include "mongo/db/instance.h"
 #include "mongo/stdx/thread.h"
 #include "mongo/transport/service_entry_point_utils.h"
 #include "mongo/transport/session.h"
diff --git a/src/mongo/db/storage/mmap_v1/btree/btree_logic_test.cpp b/src/mongo/db/storage/mmap_v1/btree/btree_logic_test.cpp
index df9d85e9b84..5d24c5b5713 100644
--- a/src/mongo/db/storage/mmap_v1/btree/btree_logic_test.cpp
+++ b/src/mongo/db/storage/mmap_v1/btree/btree_logic_test.cpp
@@ -34,7 +34,6 @@
 
 #define MONGO_LOG_DEFAULT_COMPONENT ::mongo::logger::LogComponent::kStorage
 
-#include "mongo/db/instance.h"
 #include "mongo/db/operation_context_noop.h"
 #include "mongo/db/storage/mmap_v1/btree/btree_test_help.h"
 #include "mongo/unittest/unittest.h"
diff --git a/src/mongo/db/storage/mmap_v1/data_file_sync.cpp b/src/mongo/db/storage/mmap_v1/data_file_sync.cpp
index 5fe552d0dce..51a091dd7f2 100644
--- a/src/mongo/db/storage/mmap_v1/data_file_sync.cpp
+++ b/src/mongo/db/storage/mmap_v1/data_file_sync.cpp
@@ -35,7 +35,6 @@
 #include "mongo/db/client.h"
 #include "mongo/db/commands/server_status_metric.h"
 #include "mongo/db/diag_log.h"
-#include "mongo/db/instance.h"
 #include "mongo/db/service_context.h"
 #include "mongo/db/storage/mmap_v1/dur_journal.h"
 #include "mongo/db/storage/mmap_v1/mmap.h"
diff --git a/src/mongo/dbtests/basictests.cpp b/src/mongo/dbtests/basictests.cpp
index f0f68d05c97..d9a16934d8e 100644
--- a/src/mongo/dbtests/basictests.cpp
+++ b/src/mongo/dbtests/basictests.cpp
@@ -43,6 +43,7 @@
 #include "mongo/util/text.h"
 #include "mongo/util/thread_safe_string.h"
 #include "mongo/util/time_support.h"
+#include "mongo/util/timer.h"
 
 namespace BasicTests {
 
diff --git a/src/mongo/dbtests/dbtests.cpp b/src/mongo/dbtests/dbtests.cpp
index 78ad3a66807..8bcd72ff37d 100644
--- a/src/mongo/dbtests/dbtests.cpp
+++ b/src/mongo/dbtests/dbtests.cpp
@@ -34,6 +34,7 @@
 #include "mongo/dbtests/dbtests.h"
 
 #include "mongo/base/initializer.h"
+#include "mongo/client/dbclientinterface.h"
 #include "mongo/db/auth/authorization_manager.h"
 #include "mongo/db/auth/authorization_manager_global.h"
 #include "mongo/db/catalog/index_create.h"
diff --git a/src/mongo/dbtests/dbtests.h b/src/mongo/dbtests/dbtests.h
index 09dcfcfbbc7..86de296e53d 100644
--- a/src/mongo/dbtests/dbtests.h
+++ b/src/mongo/dbtests/dbtests.h
@@ -31,8 +31,6 @@
 
 #pragma once
 
-
-#include "mongo/db/instance.h"
 #include "mongo/unittest/unittest.h"
 
 using namespace mongo;
diff --git a/src/mongo/dbtests/jsobjtests.cpp b/src/mongo/dbtests/jsobjtests.cpp
index 4b5943cdc8f..917488bd1c0 100644
--- a/src/mongo/dbtests/jsobjtests.cpp
+++ b/src/mongo/dbtests/jsobjtests.cpp
@@ -49,6 +49,7 @@
 #include "mongo/util/embedded_builder.h"
 #include "mongo/util/log.h"
 #include "mongo/util/stringutils.h"
+#include "mongo/util/timer.h"
 
 namespace mongo {
 
diff --git a/src/mongo/dbtests/mmaptests.cpp b/src/mongo/dbtests/mmaptests.cpp
index 73e6fc20f83..2090e66d4b5 100644
--- a/src/mongo/dbtests/mmaptests.cpp
+++ b/src/mongo/dbtests/mmaptests.cpp
@@ -33,6 +33,7 @@
 #include <boost/filesystem/operations.hpp>
 #include <iostream>
 
+#include "mongo/db/concurrency/d_concurrency.h"
 #include "mongo/db/concurrency/lock_state.h"
 #include "mongo/db/service_context.h"
 #include "mongo/db/storage/mmap_v1/data_file.h"
diff --git a/src/mongo/dbtests/query_stage_ixscan.cpp b/src/mongo/dbtests/query_stage_ixscan.cpp
index 4f39d27588e..45ee7723ecf 100644
--- a/src/mongo/dbtests/query_stage_ixscan.cpp
+++ b/src/mongo/dbtests/query_stage_ixscan.cpp
@@ -28,6 +28,7 @@
 
 #include "mongo/platform/basic.h"
 
+#include "mongo/client/dbclientinterface.h"
 #include "mongo/db/client.h"
 #include "mongo/db/db_raii.h"
 #include "mongo/db/exec/index_scan.h"
diff --git a/src/mongo/dbtests/query_stage_limit_skip.cpp b/src/mongo/dbtests/query_stage_limit_skip.cpp
index 0009f32ea8c..103f5932255 100644
--- a/src/mongo/dbtests/query_stage_limit_skip.cpp
+++ b/src/mongo/dbtests/query_stage_limit_skip.cpp
@@ -39,7 +39,6 @@
 #include "mongo/db/exec/plan_stage.h"
 #include "mongo/db/exec/queued_data_stage.h"
 #include "mongo/db/exec/skip.h"
-#include "mongo/db/instance.h"
 #include "mongo/db/json.h"
 #include "mongo/dbtests/dbtests.h"
 #include "mongo/stdx/memory.h"
diff --git a/src/mongo/dbtests/socktests.cpp b/src/mongo/dbtests/socktests.cpp
index def0cfdb176..e0a9fbb2fed 100644
--- a/src/mongo/dbtests/socktests.cpp
+++ b/src/mongo/dbtests/socktests.cpp
@@ -33,6 +33,8 @@
 
 #include "mongo/db/repl/isself.h"
 #include "mongo/dbtests/dbtests.h"
+#include "mongo/util/net/hostandport.h"
+#include "mongo/util/net/sock.h"
 
 namespace SockTests {
 
diff --git a/src/mongo/s/server.cpp b/src/mongo/s/server.cpp
index 2bad7e6063f..52615b92aa3 100644
--- a/src/mongo/s/server.cpp
+++ b/src/mongo/s/server.cpp
@@ -52,7 +52,6 @@
 #include "mongo/db/client.h"
 #include "mongo/db/dbwebserver.h"
 #include "mongo/db/initialize_server_global_state.h"
-#include "mongo/db/instance.h"
 #include "mongo/db/lasterror.h"
 #include "mongo/db/log_process_details.h"
 #include "mongo/db/server_options.h"