subsystem

Author: achamayou

src/enclave/enclave.h

@@ -24,6 +24,7 @@
 #include "node/rpc/custom_protocol_subsystem.h"
 #include "node/rpc/forwarder.h"
 #include "node/rpc/gov_effects.h"
+#include "node/rpc/ledger_subsystem.h"
 #include "node/rpc/member_frontend.h"
 #include "node/rpc/network_identity_subsystem.h"
 #include "node/rpc/node_frontend.h"
@@ -137,7 +138,9 @@ namespace ccf
       context->install_subsystem(cpss);
       rpcsessions->set_custom_protocol_subsystem(cpss);
 
-      // TODO: install a ledger files subsystem to manage ledger access
+      auto ledger_subsystem =
+        std::make_shared<ccf::ReadLedgerSubsystem>(ledger_);
+      context->install_subsystem(ledger_subsystem);
 
       static constexpr size_t max_interpreter_cache_size = 10;
       auto interpreter_cache =

src/node/rpc/ledger_interface.h

@@ -0,0 +1,25 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the Apache 2.0 License.
+#pragma once
+
+#include "ccf/node_subsystem_interface.h"
+
+#include <filesystem>
+#include <optional>
+
+namespace ccf
+{
+  class AbstractReadLedgerSubsystemInterface : public AbstractNodeSubSystem
+  {
+  public:
+    ~AbstractReadLedgerSubsystemInterface() override = default;
+
+    static char const* get_subsystem_name()
+    {
+      return "LedgerReadInterface";
+    }
+
+    virtual std::optional<std::filesystem::path> committed_ledger_path_with_idx(
+      size_t idx) = 0;
+  };
+}

src/node/rpc/ledger_subsystem.h

@@ -0,0 +1,24 @@
+// Copyright (c) Microsoft Corporation. All rights reserved.
+// Licensed under the Apache 2.0 License.
+#pragma once
+
+#include "host/ledger.h"
+#include "node/rpc/ledger_interface.h"
+
+namespace ccf
+{
+  class ReadLedgerSubsystem : public AbstractReadLedgerSubsystemInterface
+  {
+  protected:
+    asynchost::Ledger& ledger;
+
+  public:
+    ReadLedgerSubsystem(asynchost::Ledger& ledger_) : ledger(ledger_) {}
+
+    [[nodiscard]] std::optional<std::filesystem::path>
+    committed_ledger_path_with_idx(size_t idx) override
+    {
+      return ledger.committed_ledger_path_with_idx(idx);
+    }
+  };
+}