Extend peer shard info

Builds/CMake/RippledCore.cmake

@@ -521,6 +521,7 @@ target_sources (rippled PRIVATE
   src/ripple/nodestore/impl/ManagerImp.cpp
   src/ripple/nodestore/impl/NodeObject.cpp
   src/ripple/nodestore/impl/Shard.cpp
+  src/ripple/nodestore/impl/ShardInfo.cpp
   src/ripple/nodestore/impl/TaskQueue.cpp
   #[===============================[
      main sources:

Builds/levelization/results/loops.txt

@@ -41,7 +41,7 @@ Loop: ripple.net ripple.rpc
   ripple.rpc > ripple.net
 
 Loop: ripple.nodestore ripple.overlay
-  ripple.overlay == ripple.nodestore
+  ripple.overlay ~= ripple.nodestore
 
 Loop: ripple.overlay ripple.rpc
   ripple.rpc ~= ripple.overlay

src/ripple/basics/RangeSet.h

@@ -98,18 +98,15 @@ template <class T>
 std::string
 to_string(RangeSet<T> const& rs)
 {
-    using ripple::to_string;
-
     if (rs.empty())
         return "empty";
-    std::string res = "";
+
+    std::string s;
     for (auto const& interval : rs)
-    {
-        if (!res.empty())
-            res += ",";
-        res += to_string(interval);
-    }
-    return res;
+        s += ripple::to_string(interval) + ",";
+    s.pop_back();
+
+    return s;
 }
 
 /** Convert the given styled string to a RangeSet.
@@ -122,13 +119,14 @@ to_string(RangeSet<T> const& rs)
     @return True on successfully converting styled string
 */
 template <class T>
-bool
+[[nodiscard]] bool
 from_string(RangeSet<T>& rs, std::string const& s)
 {
     std::vector<std::string> intervals;
     std::vector<std::string> tokens;
     bool result{true};
 
+    rs.clear();
     boost::split(tokens, s, boost::algorithm::is_any_of(","));
     for (auto const& t : tokens)
     {

src/ripple/nodestore/Database.h

@@ -226,14 +226,79 @@ class Database : public Stoppable
     void
     onChildrenStopped() override;
 
+    /** @return The maximum number of ledgers stored in a shard
+     */
+    [[nodiscard]] std::uint32_t
+    ledgersPerShard() const noexcept
+    {
+        return ledgersPerShard_;
+    }
+
     /** @return The earliest ledger sequence allowed
      */
-    std::uint32_t
-    earliestLedgerSeq() const
+    [[nodiscard]] std::uint32_t
+    earliestLedgerSeq() const noexcept
     {
         return earliestLedgerSeq_;
     }
 
+    /** @return The earliest shard index
+     */
+    [[nodiscard]] std::uint32_t
+    earliestShardIndex() const noexcept
+    {
+        return earliestShardIndex_;
+    }
+
+    /** Calculates the first ledger sequence for a given shard index
+
+        @param shardIndex The shard index considered
+        @return The first ledger sequence pertaining to the shard index
+    */
+    [[nodiscard]] std::uint32_t
+    firstLedgerSeq(std::uint32_t shardIndex) const noexcept
+    {
+        assert(shardIndex >= earliestShardIndex_);
+        if (shardIndex <= earliestShardIndex_)
+            return earliestLedgerSeq_;
+        return 1 + (shardIndex * ledgersPerShard_);
+    }
+
+    /** Calculates the last ledger sequence for a given shard index
+
+        @param shardIndex The shard index considered
+        @return The last ledger sequence pertaining to the shard index
+    */
+    [[nodiscard]] std::uint32_t
+    lastLedgerSeq(std::uint32_t shardIndex) const noexcept
+    {
+        assert(shardIndex >= earliestShardIndex_);
+        return (shardIndex + 1) * ledgersPerShard_;
+    }
+
+    /** Calculates the shard index for a given ledger sequence
+
+        @param ledgerSeq ledger sequence
+        @return The shard index of the ledger sequence
+    */
+    [[nodiscard]] std::uint32_t
+    seqToShardIndex(std::uint32_t ledgerSeq) const noexcept
+    {
+        assert(ledgerSeq >= earliestLedgerSeq_);
+        return (ledgerSeq - 1) / ledgersPerShard_;
+    }
+
+    /** Calculates the maximum ledgers for a given shard index
+
+        @param shardIndex The shard index considered
+        @return The maximum ledgers pertaining to the shard index
+
+        @note The earliest shard may store less if the earliest ledger
+        sequence truncates its beginning
+    */
+    [[nodiscard]] std::uint32_t
+    maxLedgers(std::uint32_t shardIndex) const noexcept;
+
 protected:
     beast::Journal const j_;
     Scheduler& scheduler_;
@@ -242,6 +307,25 @@ class Database : public Stoppable
     std::atomic<std::uint32_t> fetchHitCount_{0};
     std::atomic<std::uint32_t> fetchSz_{0};
 
+    // The default is DEFAULT_LEDGERS_PER_SHARD (16384) to match the XRP ledger
+    // network. Can be set through the configuration file using the
+    // 'ledgers_per_shard' field under the 'node_db' and 'shard_db' stanzas.
+    // If specified, the value must be a multiple of 256 and equally assigned
+    // in both stanzas. Only unit tests or alternate networks should change
+    // this value.
+    std::uint32_t const ledgersPerShard_;
+
+    // The default is XRP_LEDGER_EARLIEST_SEQ (32570) to match the XRP ledger
+    // network's earliest allowed ledger sequence. Can be set through the
+    // configuration file using the 'earliest_seq' field under the 'node_db'
+    // and 'shard_db' stanzas. If specified, the value must be greater than zero
+    // and equally assigned in both stanzas. Only unit tests or alternate
+    // networks should change this value.
+    std::uint32_t const earliestLedgerSeq_;
+
+    // The earliest shard index
+    std::uint32_t const earliestShardIndex_;
+
     void
     stopReadThreads();
 
@@ -293,10 +377,6 @@ class Database : public Stoppable
     std::vector<std::thread> readThreads_;
     bool readShut_{false};
 
-    // The default is 32570 to match the XRP ledger network's earliest
-    // allowed sequence. Alternate networks may set this value.
-    std::uint32_t const earliestLedgerSeq_;
-
     virtual std::shared_ptr<NodeObject>
     fetchNodeObject(
         uint256 const& hash,

src/ripple/nodestore/DatabaseShard.h

@@ -21,9 +21,9 @@
 #define RIPPLE_NODESTORE_DATABASESHARD_H_INCLUDED
 
 #include <ripple/app/ledger/Ledger.h>
-#include <ripple/basics/RangeSet.h>
-#include <ripple/core/DatabaseCon.h>
+#include <ripple/core/SociDB.h>
 #include <ripple/nodestore/Database.h>
+#include <ripple/nodestore/ShardInfo.h>
 #include <ripple/nodestore/Types.h>
 
 #include <memory>
@@ -61,7 +61,7 @@ class DatabaseShard : public Database
 
         @return `true` if the database initialized without error
     */
-    virtual bool
+    [[nodiscard]] virtual bool
     init() = 0;
 
     /** Prepare to store a new ledger in the shard being acquired
@@ -76,15 +76,15 @@ class DatabaseShard : public Database
                 between requests.
         @implNote adds a new writable shard if necessary
     */
-    virtual std::optional<std::uint32_t>
+    [[nodiscard]] virtual std::optional<std::uint32_t>
     prepareLedger(std::uint32_t validLedgerSeq) = 0;
 
     /** Prepare one or more shard indexes to be imported into the database
 
         @param shardIndexes Shard indexes to be prepared for import
         @return true if all shard indexes successfully prepared for import
     */
-    virtual bool
+    [[nodiscard]] virtual bool
     prepareShards(std::vector<std::uint32_t> const& shardIndexes) = 0;
 
     /** Remove a previously prepared shard index for import
@@ -98,7 +98,7 @@ class DatabaseShard : public Database
 
         @return a string representing the shards prepared for import
     */
-    virtual std::string
+    [[nodiscard]] virtual std::string
     getPreShards() = 0;
 
     /** Import a shard into the shard database
@@ -108,7 +108,7 @@ class DatabaseShard : public Database
         @return true If the shard was successfully imported
         @implNote if successful, srcDir is moved to the database directory
     */
-    virtual bool
+    [[nodiscard]] virtual bool
     importShard(
         std::uint32_t shardIndex,
         boost::filesystem::path const& srcDir) = 0;
@@ -119,7 +119,7 @@ class DatabaseShard : public Database
         @param seq The sequence of the ledger
         @return The ledger if found, nullptr otherwise
     */
-    virtual std::shared_ptr<Ledger>
+    [[nodiscard]] virtual std::shared_ptr<Ledger>
     fetchLedger(uint256 const& hash, std::uint32_t seq) = 0;
 
     /** Notifies the database that the given ledger has been
@@ -130,13 +130,6 @@ class DatabaseShard : public Database
     virtual void
     setStored(std::shared_ptr<Ledger const> const& ledger) = 0;
 
-    /** Query which complete shards are stored
-
-        @return the indexes of complete shards
-    */
-    virtual std::string
-    getCompleteShards() = 0;
-
     /**
      * @brief callForLedgerSQL Checkouts ledger database for shard
      *        containing given ledger and calls given callback function passing
@@ -233,57 +226,24 @@ class DatabaseShard : public Database
         std::function<bool(soci::session& session, std::uint32_t index)> const&
             callback) = 0;
 
-    /** @return The maximum number of ledgers stored in a shard
-     */
-    virtual std::uint32_t
-    ledgersPerShard() const = 0;
-
-    /** @return The earliest shard index
-     */
-    virtual std::uint32_t
-    earliestShardIndex() const = 0;
-
-    /** Calculates the shard index for a given ledger sequence
+    /** Query information about shards held
 
-        @param seq ledger sequence
-        @return The shard index of the ledger sequence
+        @return Information about shards held by this node
     */
-    virtual std::uint32_t
-    seqToShardIndex(std::uint32_t seq) const = 0;
-
-    /** Calculates the first ledger sequence for a given shard index
-
-        @param shardIndex The shard index considered
-        @return The first ledger sequence pertaining to the shard index
-    */
-    virtual std::uint32_t
-    firstLedgerSeq(std::uint32_t shardIndex) const = 0;
-
-    /** Calculates the last ledger sequence for a given shard index
-
-        @param shardIndex The shard index considered
-        @return The last ledger sequence pertaining to the shard index
-    */
-    virtual std::uint32_t
-    lastLedgerSeq(std::uint32_t shardIndex) const = 0;
+    [[nodiscard]] virtual std::unique_ptr<ShardInfo>
+    getShardInfo() const = 0;
 
     /** Returns the root database directory
      */
-    virtual boost::filesystem::path const&
+    [[nodiscard]] virtual boost::filesystem::path const&
     getRootDir() const = 0;
 
-    /** The number of ledgers in a shard */
-    static constexpr std::uint32_t ledgersPerShardDefault{16384u};
+    /** Returns the number of queued tasks
+     */
+    [[nodiscard]] virtual size_t
+    getNumTasks() const = 0;
 };
 
-constexpr std::uint32_t
-seqToShardIndex(
-    std::uint32_t ledgerSeq,
-    std::uint32_t ledgersPerShard = DatabaseShard::ledgersPerShardDefault)
-{
-    return (ledgerSeq - 1) / ledgersPerShard;
-}
-
 extern std::unique_ptr<DatabaseShard>
 make_ShardStore(
     Application& app,