PathRequest.h

#pragma once
 
#include <xrpld/app/ledger/Ledger.h>
#include <xrpld/app/paths/Pathfinder.h>
#include <xrpld/app/paths/RippleLineCache.h>
 
#include <xrpl/basics/base_uint.h>
#include <xrpl/json/json_value.h>
#include <xrpl/protocol/UintTypes.h>
#include <xrpl/server/InfoSub.h>
 
#include <map>
#include <mutex>
#include <optional>
#include <set>
 
namespace xrpl {
 
// A pathfinding request submitted by a client
// The request issuer must maintain a strong pointer
 
class RippleLineCache;
class PathRequests;
 
// Return values from parseJson <0 = invalid, >0 = valid
#define PFR_PJ_INVALID -1
#define PFR_PJ_NOCHANGE 0
 
class PathRequest final : public InfoSubRequest,
                          public std::enable_shared_from_this<PathRequest>,
                          public CountedObject<PathRequest>
{
public:
    using wptr = std::weak_ptr<PathRequest>;
    using pointer = std::shared_ptr<PathRequest>;
    using ref = pointer const&;
    using wref = wptr const&;
 
public:
    // path_find semantics
    // Subscriber is updated
    PathRequest(
        Application& app,
        std::shared_ptr<InfoSub> const& subscriber,
        int id,
        PathRequests&,
        beast::Journal journal);
 
    // ripple_path_find semantics
    // Completion function is called after path update is complete
    PathRequest(
        Application& app,
        std::function<void(void)> const& completion,
        Resource::Consumer& consumer,
        int id,
        PathRequests&,
        beast::Journal journal);
 
    ~PathRequest();
 
    bool
    isNew();
    bool
    needsUpdate(bool newOnly, LedgerIndex index);
 
    // Called when the PathRequest update is complete.
    void
    updateComplete();
 
    std::pair<bool, Json::Value>
    doCreate(std::shared_ptr<RippleLineCache> const&, Json::Value const&);
 
    Json::Value
    doClose() override;
    Json::Value
    doStatus(Json::Value const&) override;
    void
    doAborting() const;
 
    // update jvStatus
    Json::Value
    doUpdate(
        std::shared_ptr<RippleLineCache> const&,
        bool fast,
        std::function<bool(void)> const& continueCallback = {});
    InfoSub::pointer
    getSubscriber() const;
    bool
    hasCompletion();
 
private:
    bool
    isValid(std::shared_ptr<RippleLineCache> const& crCache);
 
    std::unique_ptr<Pathfinder> const&
    getPathFinder(
        std::shared_ptr<RippleLineCache> const&,
        hash_map<Currency, std::unique_ptr<Pathfinder>>&,
        Currency const&,
        STAmount const&,
        int const,
        std::function<bool(void)> const&);
 
    bool
    findPaths(std::shared_ptr<RippleLineCache> const&, int const, Json::Value&, std::function<bool(void)> const&);
 
    int
    parseJson(Json::Value const&);
 
    Application& app_;
    beast::Journal m_journal;
 
    std::recursive_mutex mLock;
 
    PathRequests& mOwner;
 
    std::weak_ptr<InfoSub> wpSubscriber;  // Who this request came from
    std::function<void(void)> fCompletion;
    Resource::Consumer& consumer_;  // Charge according to source currencies
 
    Json::Value jvId;
    Json::Value jvStatus;  // Last result
 
    // Client request parameters
    std::optional<AccountID> raSrcAccount;
    std::optional<AccountID> raDstAccount;
    STAmount saDstAmount;
    std::optional<STAmount> saSendMax;
 
    std::set<Issue> sciSourceCurrencies;
    std::map<Issue, STPathSet> mContext;
 
    std::optional<uint256> domain;
 
    bool convert_all_;
 
    std::recursive_mutex mIndexLock;
    LedgerIndex mLastIndex;
    bool mInProgress;
 
    int iLevel;
    bool bLastSuccess;
 
    int const iIdentifier;
 
    std::chrono::steady_clock::time_point const created_;
    std::chrono::steady_clock::time_point quick_reply_;
    std::chrono::steady_clock::time_point full_reply_;
 
    static unsigned int const max_paths_ = 4;
};
 
}  // namespace xrpl