feat: export ledger name spaces via server_definitions

include/xrpl/protocol/Indexes.h

@@ -17,11 +17,46 @@
 #include <array>
 #include <cstdint>
 #include <functional>
+#include <map>
 #include <set>
+#include <string>
 #include <utility>
 
 namespace xrpl {
 
+/**
+ * Type-specific prefix for calculating ledger indices.
+ *
+ * The identifier for a given object within the ledger is calculated based
+ * on some object-specific parameters. To ensure that different types of
+ * objects have different indices, even if they happen to use the same set
+ * of parameters, we use "tagged hashing" by adding a type-specific prefix.
+ *
+ * The name spaces are listed in detail/ledger_name_spaces.macro.
+ */
+#pragma push_macro("LEDGER_NAME_SPACE")
+#undef LEDGER_NAME_SPACE
+#pragma push_macro("LEDGER_NAME_SPACE_DEPRECATED")
+#undef LEDGER_NAME_SPACE_DEPRECATED
+
+#define LEDGER_NAME_SPACE(name, value) name = (value),
+#define LEDGER_NAME_SPACE_DEPRECATED(name, value) name [[deprecated]] = (value),
+
+enum class LedgerNameSpace : std::uint16_t {
+#include <xrpl/protocol/detail/ledger_name_spaces.macro>
+};
+
+#undef LEDGER_NAME_SPACE_DEPRECATED
+#pragma pop_macro("LEDGER_NAME_SPACE_DEPRECATED")
+#undef LEDGER_NAME_SPACE
+#pragma pop_macro("LEDGER_NAME_SPACE")
+
+/**
+ * The name->value map of active (non-deprecated) ledger name spaces.
+ */
+std::map<std::string, std::uint16_t> const&
+ledgerNameSpaceMap();
+
 class SeqProxy;
 /**
  * Keylet computation functions.

include/xrpl/protocol/detail/ledger_name_spaces.macro

@@ -0,0 +1,59 @@
+#if !defined(LEDGER_NAME_SPACE)
+#error "undefined macro: LEDGER_NAME_SPACE"
+#endif
+#if !defined(LEDGER_NAME_SPACE_DEPRECATED)
+#error "undefined macro: LEDGER_NAME_SPACE_DEPRECATED"
+#endif
+
+// Active ledger name spaces.
+//
+// @note These values are part of the protocol and *CANNOT* be arbitrarily
+//       changed. If they were, on-ledger objects may no longer be able to
+//       be located or addressed.
+//
+//       Additions to this list are OK, but changing existing entries to
+//       assign them a different values should never be needed.
+//
+//       Entries that are removed should be moved to the deprecated list
+//       below to prevent accidental reuse.
+LEDGER_NAME_SPACE(Account, 'a')
+LEDGER_NAME_SPACE(DirNode, 'd')
+LEDGER_NAME_SPACE(TrustLine, 'r')
+LEDGER_NAME_SPACE(Offer, 'o')
+LEDGER_NAME_SPACE(OwnerDir, 'O')
+LEDGER_NAME_SPACE(BookDir, 'B')
+LEDGER_NAME_SPACE(SkipList, 's')
+LEDGER_NAME_SPACE(Escrow, 'u')
+LEDGER_NAME_SPACE(Amendments, 'f')
+LEDGER_NAME_SPACE(FeeSettings, 'e')
+LEDGER_NAME_SPACE(Ticket, 'T')
+LEDGER_NAME_SPACE(SignerList, 'S')
+LEDGER_NAME_SPACE(XRPPaymentChannel, 'x')
+LEDGER_NAME_SPACE(Check, 'C')
+LEDGER_NAME_SPACE(DepositPreauth, 'p')
+LEDGER_NAME_SPACE(DepositPreauthCredentials, 'P')
+LEDGER_NAME_SPACE(NegativeUnl, 'N')
+LEDGER_NAME_SPACE(NftokenOffer, 'q')
+LEDGER_NAME_SPACE(NftokenBuyOffers, 'h')
+LEDGER_NAME_SPACE(NftokenSellOffers, 'i')
+LEDGER_NAME_SPACE(Amm, 'A')
+LEDGER_NAME_SPACE(Bridge, 'H')
+LEDGER_NAME_SPACE(XchainClaimId, 'Q')
+LEDGER_NAME_SPACE(XchainCreateAccountClaimId, 'K')
+LEDGER_NAME_SPACE(Did, 'I')
+LEDGER_NAME_SPACE(Oracle, 'R')
+LEDGER_NAME_SPACE(MPTokenIssuance, '~')
+LEDGER_NAME_SPACE(MPToken, 't')
+LEDGER_NAME_SPACE(Credential, 'D')
+LEDGER_NAME_SPACE(PermissionedDomain, 'm')
+LEDGER_NAME_SPACE(Delegate, 'E')
+LEDGER_NAME_SPACE(Vault, 'V')
+LEDGER_NAME_SPACE(LoanBroker, 'l')  // lower-case L
+LEDGER_NAME_SPACE(Loan, 'L')
+LEDGER_NAME_SPACE(Sponsorship, '>')
+
+// No longer used or supported. Left here to reserve the space to avoid
+// accidental reuse, and intentionally not exported to clients.
+LEDGER_NAME_SPACE_DEPRECATED(Contract, 'c')
+LEDGER_NAME_SPACE_DEPRECATED(Generator, 'g')
+LEDGER_NAME_SPACE_DEPRECATED(Nickname, 'n')

include/xrpl/protocol/jss.h

@@ -350,6 +350,7 @@ JSS(LEDGER_ENTRY_TYPES);             // out: RPC server_definitions
                                      // matches definitions.json format
 JSS(LEDGER_ENTRY_FLAGS);             // out: RPC server_definitions
 JSS(LEDGER_ENTRY_FORMATS);           // out: RPC server_definitions
+JSS(LEDGER_NAME_SPACES);             // out: RPC server_definitions
 JSS(levels);                         // LogLevels
 JSS(limit);                       // in/out: AccountTx*, AccountOffers, AccountLines, AccountObjects
                                   // in: LedgerData, BookOffers