/** @file dbcommands_generic.cpp commands suited for any mongo server (both mongod, mongos) */

/**
*    Copyright (C) 2012 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.
*/

#define MONGO_LOG_DEFAULT_COMPONENT ::mongo::logger::LogComponent::kCommand

#include "mongo/platform/basic.h"

#include <time.h>

#include "mongo/bson/util/builder.h"
#include "mongo/client/dbclient_rs.h"
#include "mongo/db/auth/action_set.h"
#include "mongo/db/auth/action_type.h"
#include "mongo/db/auth/authorization_manager.h"
#include "mongo/db/auth/privilege.h"
#include "mongo/db/background.h"
#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"
#include "mongo/db/lasterror.h"
#include "mongo/db/log_process_details.h"
#include "mongo/db/server_options.h"
#include "mongo/db/service_context.h"
#include "mongo/db/stats/counters.h"
#include "mongo/scripting/engine.h"
#include "mongo/util/exit.h"
#include "mongo/util/fail_point.h"
#include "mongo/util/fail_point_service.h"
#include "mongo/util/log.h"
#include "mongo/util/md5.hpp"
#include "mongo/util/ntservice.h"
#include "mongo/util/processinfo.h"
#include "mongo/util/ramlog.h"
#include "mongo/util/version.h"

namespace mongo {

    using std::endl;
    using std::string;
    using std::stringstream;
    using std::vector;

    class CmdBuildInfo : public Command {
    public:
        CmdBuildInfo() : Command( "buildInfo", true, "buildinfo" ) {}
        virtual bool slaveOk() const { return true; }
        virtual bool adminOnly() const { return false; }
        virtual bool isWriteCommandForConfigServer() const { return false; }
        virtual void addRequiredPrivileges(const std::string& dbname,
                                           const BSONObj& cmdObj,
                                           std::vector<Privilege>* out) {} // No auth required
        virtual void help( stringstream &help ) const {
            help << "get version #, etc.\n";
            help << "{ buildinfo:1 }";
        }

        bool run(OperationContext* txn, const std::string& dbname,
                 BSONObj& jsobj,
                 int, // options
                 std::string& errmsg,
                 BSONObjBuilder& result) {
        appendBuildInfo(result);
        appendStorageEngineList(&result);
        return true;

        }

    } cmdBuildInfo;


    class PingCommand : public Command {
    public:
        PingCommand() : Command( "ping" ) {}
        virtual bool slaveOk() const { return true; }
        virtual void help( stringstream &help ) const { help << "a way to check that the server is alive. responds immediately even if server is in a db lock."; }
        virtual bool isWriteCommandForConfigServer() const { return false; }
        virtual void addRequiredPrivileges(const std::string& dbname,
                                           const BSONObj& cmdObj,
                                           std::vector<Privilege>* out) {} // No auth required
        virtual bool run(OperationContext* txn,
                         const string& badns,
                         BSONObj& cmdObj,
                         int,
                         string& errmsg,
                         BSONObjBuilder& result) {
            // IMPORTANT: Don't put anything in here that might lock db - including authentication
            return true;
        }
    } pingCmd;

    class FeaturesCmd : public Command {
    public:
        FeaturesCmd() : Command( "features", true ) {}
        void help(stringstream& h) const { h << "return build level feature settings"; }
        virtual bool slaveOk() const { return true; }
        virtual bool isWriteCommandForConfigServer() const { return false; }
        virtual void addRequiredPrivileges(const std::string& dbname,
                                           const BSONObj& cmdObj,
                                           std::vector<Privilege>* out) {} // No auth required
        virtual bool run(OperationContext* txn,
                         const string& ns,
                         BSONObj& cmdObj,
                         int,
                         string& errmsg,
                         BSONObjBuilder& result) {
            if ( globalScriptEngine ) {
                BSONObjBuilder bb( result.subobjStart( "js" ) );
                result.append( "utf8" , globalScriptEngine->utf8Ok() );
                bb.done();
            }
            if ( cmdObj["oidReset"].trueValue() ) {
                result.append( "oidMachineOld" , OID::getMachineId() );
                OID::regenMachineId();
            }
            result.append( "oidMachine" , OID::getMachineId() );
            return true;
        }

    } featuresCmd;

    class HostInfoCmd : public Command {
    public:
        HostInfoCmd() : Command("hostInfo", true) {}
        virtual bool slaveOk() const {
            return true;
        }

        virtual bool isWriteCommandForConfigServer() const { return false; }

        virtual void help( stringstream& help ) const {
            help << "returns information about the daemon's host";
        }
        virtual void addRequiredPrivileges(const std::string& dbname,
                                           const BSONObj& cmdObj,
                                           std::vector<Privilege>* out) {
            ActionSet actions;
            actions.addAction(ActionType::hostInfo);
            out->push_back(Privilege(ResourcePattern::forClusterResource(), actions));
        }
        bool run(OperationContext* txn,
                 const string& dbname,
                 BSONObj& cmdObj,
                 int,
                 string& errmsg,
                 BSONObjBuilder& result) {
            ProcessInfo p;
            BSONObjBuilder bSys, bOs;

            bSys.appendDate( "currentTime" , jsTime() );
            bSys.append( "hostname" , prettyHostName() );
            bSys.append( "cpuAddrSize", p.getAddrSize() );
            bSys.append( "memSizeMB", static_cast <unsigned>( p.getMemSizeMB() ) );
            bSys.append( "numCores", p.getNumCores() );
            bSys.append( "cpuArch", p.getArch() );
            bSys.append( "numaEnabled", p.hasNumaEnabled() );
            bOs.append( "type", p.getOsType() );
            bOs.append( "name", p.getOsName() );
            bOs.append( "version", p.getOsVersion() );

            result.append( StringData( "system" ), bSys.obj() );
            result.append( StringData( "os" ), bOs.obj() );
            p.appendSystemDetails( result );

            return true;
        }

    } hostInfoCmd;

    class LogRotateCmd : public Command {
    public:
        LogRotateCmd() : Command( "logRotate" ) {}
        virtual bool isWriteCommandForConfigServer() const { return false; }
        virtual bool slaveOk() const { return true; }
        virtual bool adminOnly() const { return true; }
        virtual void addRequiredPrivileges(const std::string& dbname,
                                           const BSONObj& cmdObj,
                                           std::vector<Privilege>* out) {
            ActionSet actions;
            actions.addAction(ActionType::logRotate);
            out->push_back(Privilege(ResourcePattern::forClusterResource(), actions));
        }
        virtual bool run(OperationContext* txn,
                         const string& ns,
                         BSONObj& cmdObj,
                         int,
                         string& errmsg,
                         BSONObjBuilder& result) {
            bool didRotate = rotateLogs(serverGlobalParams.logRenameOnRotate);
            if (didRotate)
                logProcessDetailsForLogRotate();
            return didRotate;
        }

    } logRotateCmd;

    class ListCommandsCmd : public Command {
    public:
        virtual void help( stringstream &help ) const { help << "get a list of all db commands"; }
        ListCommandsCmd() : Command( "listCommands", false ) {}
        virtual bool isWriteCommandForConfigServer() const { return false; }
        virtual bool slaveOk() const { return true; }
        virtual bool adminOnly() const { return false; }
        virtual void addRequiredPrivileges(const std::string& dbname,
                                           const BSONObj& cmdObj,
                                           std::vector<Privilege>* out) {} // No auth required
        virtual bool run(OperationContext* txn,
                         const string& ns,
                         BSONObj& cmdObj,
                         int,
                         string& errmsg,
                         BSONObjBuilder& result) {
            BSONObjBuilder b( result.subobjStart( "commands" ) );
            for ( CommandMap::const_iterator i=_commands->begin(); i!=_commands->end(); ++i ) {
                Command * c = i->second;

                // don't show oldnames
                if (i->first != c->name)
                    continue;

                BSONObjBuilder temp( b.subobjStart( c->name ) );

                {
                    stringstream help;
                    c->help( help );
                    temp.append( "help" , help.str() );
                }
                temp.append( "slaveOk" , c->slaveOk() );
                temp.append( "adminOnly" , c->adminOnly() );
                //optionally indicates that the command can be forced to run on a slave/secondary
                if ( c->slaveOverrideOk() ) temp.append( "slaveOverrideOk" , c->slaveOverrideOk() );
                temp.done();
            }
            b.done();

            return 1;
        }

    } listCommandsCmd;

    namespace {
        MONGO_FP_DECLARE(crashOnShutdown);

        int* volatile illegalAddress;
    }  // namespace

    void CmdShutdown::addRequiredPrivileges(const std::string& dbname,
        const BSONObj& cmdObj,
        std::vector<Privilege>* out) {
        ActionSet actions;
        actions.addAction(ActionType::shutdown);
        out->push_back(Privilege(ResourcePattern::forClusterResource(), actions));
    }

    void CmdShutdown::shutdownHelper() {
        MONGO_FAIL_POINT_BLOCK(crashOnShutdown, crashBlock) {
            const std::string crashHow = crashBlock.getData()["how"].str();
            if (crashHow == "fault") {
                ++*illegalAddress;
            }
            ::abort();
        }

        log() << "terminating, shutdown command received";

#if defined(_WIN32)
        // Signal the ServiceMain thread to shutdown.
        if(ntservice::shouldStartService()) {
            signalShutdown();

            // Client expects us to abruptly close the socket as part of exiting
            // so this function is not allowed to return.
            // The ServiceMain thread will quit for us so just sleep until it does.
            while (true)
                sleepsecs(60); // Loop forever
        }
        else
#endif
        {
            exitCleanly(EXIT_CLEAN); // this never returns
            invariant(false);
        }
    }

    /* for testing purposes only */
    class CmdForceError : public Command {
    public:
        virtual void help( stringstream& help ) const {
            help << "for testing purposes only.  forces a user assertion exception";
        }
        virtual bool slaveOk() const {
            return true;
        }
        virtual bool isWriteCommandForConfigServer() const { return false; }
        virtual void addRequiredPrivileges(const std::string& dbname,
                                           const BSONObj& cmdObj,
                                           std::vector<Privilege>* out) {} // No auth required
        CmdForceError() : Command("forceerror") {}
        bool run(OperationContext* txn,
                 const string& dbnamne,
                 BSONObj& cmdObj,
                 int,
                 string& errmsg,
                 BSONObjBuilder& result) {
            LastError::get(cc()).setLastError(10038, "forced error");
            return false;
        }
    } cmdForceError;

    class GetLogCmd : public Command {
    public:
        GetLogCmd() : Command( "getLog" ){}

        virtual bool slaveOk() const { return true; }
        virtual bool isWriteCommandForConfigServer() const { return false; }
        virtual bool adminOnly() const { return true; }
        virtual void addRequiredPrivileges(const std::string& dbname,
                                           const BSONObj& cmdObj,
                                           std::vector<Privilege>* out) {
            ActionSet actions;
            actions.addAction(ActionType::getLog);
            out->push_back(Privilege(ResourcePattern::forClusterResource(), actions));
        }
        virtual void help( stringstream& help ) const {
            help << "{ getLog : '*' }  OR { getLog : 'global' }";
        }

        virtual bool run(OperationContext* txn,
                         const string& dbname,
                         BSONObj& cmdObj,
                         int,
                         string& errmsg,
                         BSONObjBuilder& result) {
            BSONElement val = cmdObj.firstElement();
            if (val.type() != String) {
                return appendCommandStatus(result, Status(ErrorCodes::TypeMismatch, str::stream()
                    << "Argument to getLog must be of type String; found "
                    << val.toString(false) << " of type " << typeName(val.type())));
            }

            string p = val.String();
            if ( p == "*" ) {
                vector<string> names;
                RamLog::getNames( names );

                BSONArrayBuilder arr;
                for ( unsigned i=0; i<names.size(); i++ ) {
                    arr.append( names[i] );
                }
                
                result.appendArray( "names" , arr.arr() );
            }
            else {
                RamLog* ramlog = RamLog::getIfExists(p);
                if ( ! ramlog ) {
                    errmsg = str::stream() << "no RamLog named: " << p;
                    return false;
                }
                RamLog::LineIterator rl(ramlog);

                result.appendNumber( "totalLinesWritten", rl.getTotalLinesWritten() );

                BSONArrayBuilder arr( result.subarrayStart( "log" ) );
                while (rl.more())
                    arr.append(rl.next());
                arr.done();
            }
            return true;
        }

    } getLogCmd;

    class CmdGetCmdLineOpts : Command {
    public:
        CmdGetCmdLineOpts(): Command("getCmdLineOpts") {}
        void help(stringstream& h) const { h << "get argv"; }
        virtual bool isWriteCommandForConfigServer() const { return false; }
        virtual bool adminOnly() const { return true; }
        virtual bool slaveOk() const { return true; }
        virtual void addRequiredPrivileges(const std::string& dbname,
                                           const BSONObj& cmdObj,
                                           std::vector<Privilege>* out) {
            ActionSet actions;
            actions.addAction(ActionType::getCmdLineOpts);
            out->push_back(Privilege(ResourcePattern::forClusterResource(), actions));
        }
        virtual bool run(OperationContext* txn,
                         const string&,
                         BSONObj& cmdObj,
                         int,
                         string& errmsg,
                         BSONObjBuilder& result) {
            result.append("argv", serverGlobalParams.argvArray);
            result.append("parsed", serverGlobalParams.parsedOpts);
            return true;
        }

    } cmdGetCmdLineOpts;

}