rippled/src/libxrpl/server/InfoSub.cpp

#include <xrpl/server/InfoSub.h>

#include <xrpl/basics/Log.h>
#include <xrpl/beast/utility/Journal.h>
#include <xrpl/beast/utility/instrumentation.h>
#include <xrpl/protocol/AccountID.h>
#include <xrpl/protocol/Book.h>
#include <xrpl/resource/Consumer.h>

#include <cstdint>
#include <exception>
#include <memory>
#include <mutex>

namespace xrpl {

namespace {

// Wraps a Source teardown call so that an exception from one cleanup
// step does not prevent the subsequent steps from running. Source methods
// acquire a lock and can throw std::system_error; a throw out of ~InfoSub
// during stack unwinding would terminate the process. Failures are
// reported through the Source's Journal so they reach the configured log
// sinks; JLOG itself cannot throw, so the noexcept guarantee holds.
template <typename F>
void
safeUnsub(std::uint64_t seq, F&& f, beast::Journal j) noexcept
{
    try
    {
        f();
    }
    catch (std::exception const& e)
    {
        JLOG(j.warn()) << "~InfoSub[seq=" << seq << "]: cleanup step failed: " << e.what();
    }
    catch (...)
    {
        JLOG(j.warn()) << "~InfoSub[seq=" << seq << "]: cleanup step failed: unknown exception";
    }
}

}  // namespace

// This is the primary interface into the "client" portion of the program.
// Code that wants to do normal operations on the network such as
// creating and monitoring accounts, creating transactions, and so on
// should use this interface. The RPC code will primarily be a light wrapper
// over this code.

// Eventually, it will check the node's operating mode (synced, unsynced,
// etcetera) and defer to the correct means of processing. The current
// code assumes this node is synced (and will continue to do so until
// there's a functional network.

InfoSub::InfoSub(Source& source) : source_(source), seq_(assignId())
{
}

InfoSub::InfoSub(Source& source, Consumer consumer)
    : consumer_(consumer), source_(source), seq_(assignId())
{
}

InfoSub::~InfoSub()
{
    // Each Source teardown call below acquires a server-side lock and
    // can throw. Wrap each independent call so partial failure does not
    // skip the remaining teardown steps.

    auto const& j = source_.journal();

    safeUnsub(seq_, [&] { source_.unsubTransactions(seq_); }, j);
    safeUnsub(seq_, [&] { source_.unsubRTTransactions(seq_); }, j);
    safeUnsub(seq_, [&] { source_.unsubLedger(seq_); }, j);
    safeUnsub(seq_, [&] { source_.unsubManifests(seq_); }, j);
    safeUnsub(seq_, [&] { source_.unsubServer(seq_); }, j);
    safeUnsub(seq_, [&] { source_.unsubValidations(seq_); }, j);
    safeUnsub(seq_, [&] { source_.unsubPeerStatus(seq_); }, j);
    safeUnsub(seq_, [&] { source_.unsubConsensus(seq_); }, j);

    // Use the internal unsubscribe so that it won't call
    // back to us and modify its own parameter
    if (!realTimeSubscriptions_.empty())
    {
        safeUnsub(
            seq_, [&] { source_.unsubAccountInternal(seq_, realTimeSubscriptions_, true); }, j);
    }

    if (!normalSubscriptions_.empty())
    {
        safeUnsub(
            seq_, [&] { source_.unsubAccountInternal(seq_, normalSubscriptions_, false); }, j);
    }

    for (auto const& account : accountHistorySubscriptions_)
    {
        safeUnsub(seq_, [&] { source_.unsubAccountHistoryInternal(seq_, account, false); }, j);
    }

    for (auto const& book : bookSubscriptions_)
    {
        safeUnsub(seq_, [&] { source_.unsubBookInternal(seq_, book); }, j);
    }
}

Resource::Consumer&
InfoSub::getConsumer()
{
    return consumer_;
}

std::uint64_t
InfoSub::getSeq() const
{
    return seq_;
}

void
InfoSub::onSendEmpty()
{
}

void
InfoSub::insertSubAccountInfo(AccountID const& account, bool rt)
{
    std::scoped_lock const sl(lock_);

    if (rt)
    {
        realTimeSubscriptions_.insert(account);
    }
    else
    {
        normalSubscriptions_.insert(account);
    }
}

void
InfoSub::deleteSubAccountInfo(AccountID const& account, bool rt)
{
    std::scoped_lock const sl(lock_);

    if (rt)
    {
        realTimeSubscriptions_.erase(account);
    }
    else
    {
        normalSubscriptions_.erase(account);
    }
}

bool
InfoSub::insertSubAccountHistory(AccountID const& account)
{
    std::scoped_lock const sl(lock_);
    return accountHistorySubscriptions_.insert(account).second;
}

void
InfoSub::deleteSubAccountHistory(AccountID const& account)
{
    std::scoped_lock const sl(lock_);
    accountHistorySubscriptions_.erase(account);
}

void
InfoSub::insertBookSubscription(Book const& book)
{
    std::scoped_lock const sl(lock_);
    bookSubscriptions_.insert(book);
}

void
InfoSub::deleteBookSubscription(Book const& book)
{
    std::scoped_lock const sl(lock_);
    bookSubscriptions_.erase(book);
}

void
InfoSub::clearRequest()
{
    request_.reset();
}

void
InfoSub::setRequest(std::shared_ptr<InfoSubRequest> const& req)
{
    request_ = req;
}

std::shared_ptr<InfoSubRequest> const&
InfoSub::getRequest()
{
    return request_;
}

void
InfoSub::setApiVersion(unsigned int apiVersion)
{
    apiVersion_ = apiVersion;
}

unsigned int
InfoSub::getApiVersion() const noexcept
{
    XRPL_ASSERT(apiVersion_ > 0, "xrpl::InfoSub::getApiVersion : valid API version");
    return apiVersion_;
}

}  // namespace xrpl