Pretty Print Sample

This sample demonstrates the right way to iterate over all fields in a Message object and print them.

Source code:

#include <fstream>
#include <sstream>
#include <algorithm>

#include "../../Common/Helpers.h"
#include "../../Common/Settings.h"

using namespace Settings;

namespace {
static const std::string MessageLevelIndent = "  ";

class MsgPrintFunctorBase
{
protected:

    std::string messageLevel_;
    int groupInstanceNumber_;

    explicit MsgPrintFunctorBase(const std::string & messageLevel = "") : messageLevel_(messageLevel), groupInstanceNumber_(0) {}

    void printField(Tag tag, const StringRef & tagValue)
    {
        std::clog << messageLevel_ << tag << "=" << tagValue << std::endl;
    }

    void beginGroup(Tag groupTag, const StringRef & groupTagValue)
    {
        std::clog << messageLevel_ << groupTag << "=> Group of " << groupTagValue << " item(s)" << std::endl;
        messageLevel_.append(MessageLevelIndent);
    }

    void endGroup()
    {
        std::clog << messageLevel_ << "<= End of group" << std::endl;
        messageLevel_.erase(messageLevel_.size() - MessageLevelIndent.size());
    }

    void beginGroupInstance()
    {
        std::ostringstream oss;
        oss << groupInstanceNumber_++ << ": ";
        messageLevel_.append(oss.str());
    }

    void endGroupInstance()
    {
        std::ostringstream oss;
        oss << groupInstanceNumber_ << ": ";
        messageLevel_.erase(messageLevel_.size() - oss.str().size());
    }
};

class MsgPrintFunctor : private MsgPrintFunctorBase
{
public:

    explicit MsgPrintFunctor(const std::string & messageLevel = "") : MsgPrintFunctorBase(messageLevel) {}

    void operator()(const Field & field)
    {
        Group group;

        if(field.value.toGroup(group))
        {
            beginGroup(field.tag, field.value.toStringRef());

            std::for_each(group.begin(), group.end(), MsgPrintFunctor(messageLevel_));

            endGroup();
        }
        else
            printField(field.tag, field.value.toStringRef());
    }

    void operator()(const GroupInstance & instance)
    {
        beginGroupInstance();

        std::for_each(instance.begin(), instance.end(), MsgPrintFunctor(messageLevel_));

        endGroupInstance();
    }
};

typedef std::vector<Tag> GroupTags;

class FlatMsgPrintFunctor : private MsgPrintFunctorBase
{
    const FlatMessage * msg_;
    GroupTags groupTags_;

public:

    FlatMsgPrintFunctor(const FlatMessage * msg, const GroupTags & groupTags = GroupTags(), const std::string & messageLevel = "") : MsgPrintFunctorBase(messageLevel),
        msg_(msg), groupTags_(groupTags){}

    void operator()(const FlatField & field)
    {
        if(field.tag == Tags::NoRelatedSym)
        {
            beginGroup(field.tag, field.value);

            FlatGroup group = msg_->getGroup(msg_->getFlatFieldRef(field.value));
            GroupTags groupTags(1, Tags::Symbol);
            std::for_each(group.begin(), group.end(), FlatMsgPrintFunctor(msg_, groupTags, messageLevel_));

            endGroup();
        }
        else if(std::find(groupTags_.begin(), groupTags_.end(), field.tag) == groupTags_.end())
            printField(field.tag, field.value);
    }

    void operator()(const FlatGroupInstance & instance)
    {
        beginGroupInstance();

        for(GroupTags::const_iterator iter = groupTags_.begin(); iter != groupTags_.end(); ++iter)
        {
            FlatFieldRef ref = instance.find(*iter);

            if(ref)
                printField(*iter, instance[ref]);
        }

        FlatFieldRef groupRef = instance.find(Tags::NoLegs);

        if(groupRef)
        {
            FlatGroup group = instance.getGroup(groupRef);

            beginGroup(Tags::NoLegs, group.groupFieldValue());

            GroupTags groupTags;
            groupTags.push_back(Tags::LegSymbol);
            groupTags.push_back(Tags::LegMaturityDate);
            groupTags.push_back(Tags::LegStrikePrice);
            groupTags.push_back(Tags::LegCurrency);

            std::for_each(group.begin(), group.end(), FlatMsgPrintFunctor(msg_, groupTags, messageLevel_));

            endGroup();
        }

        endGroupInstance();
    }
};
}

int main()
{
    std::clog << "Pretty print sample." << std::endl << std::endl;

    try
    {
        EngineSettings settings;
        settings.licenseStore(LicenseStore)
                .listenPort(-1);
        Engine::init(settings);

        std::ifstream msgFile("message.fix");
        std::string rawMsg((std::istreambuf_iterator<char> (msgFile)), std::istreambuf_iterator<char>());

        Message msg;
        Message::parse(rawMsg.c_str(), rawMsg.size(), MessageParsingFlag::Strict, msg);

        std::clog << "Begin of Message:" << std::endl << std::endl;

        std::for_each(msg.begin(), msg.end(), MsgPrintFunctor());

        std::clog << std::endl << "End of Message" << std::endl << std::endl;

        FlatMessage flatMsg(rawMsg.c_str(), rawMsg.size());

        GroupTags groupTags;
        groupTags.push_back(Tags::NoLegs);
        groupTags.push_back(Tags::Symbol);
        groupTags.push_back(Tags::LegSymbol);
        groupTags.push_back(Tags::LegMaturityDate);
        groupTags.push_back(Tags::LegStrikePrice);
        groupTags.push_back(Tags::LegCurrency);

        std::clog << "Begin of FlatMessage:" << std::endl << std::endl;

        std::for_each(flatMsg.begin(), flatMsg.end(), FlatMsgPrintFunctor(&flatMsg, groupTags));

        std::clog << std::endl << "End of FlatMessage" << std::endl;

        Engine::shutdown();
    }
    catch(const std::exception & ex)
    {
        processSampleException(ex.what());
        return 1;
    }

    return 0;
}