Add contains_globally_committed to kv::Set

CHANGELOG.md

@@ -9,6 +9,10 @@ and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.
 
 [5.0.0-dev12]: https://github.com/microsoft/CCF/releases/tag/ccf-5.0.0-dev12
 
+### Added
+
+- There is now a `contains_globally_committed(k)` method on `kv::Set<K>`, with the same semantics as `get_globally_committed(k)` on `kv::Map<K, V>` (#5928).
+
 ### Changed
 
 - JS endpoints marked as `"mode": "readonly"` are prevented from writing to the KV. Attempting to call `map.set(k, v)`, `map.delete(k)`, or `map.clear()` on any KV table in such an endpoint will now result in an error being thrown (#5921).

include/ccf/kv/set_handle.h

@@ -34,6 +34,21 @@ namespace kv
       return read_handle.has(KSerialiser::to_serialised(key));
     }
 
+    /** Test whether a key's presence is globally committed, meaning it has been
+     * replciated and acknowledged by consensus protocol.
+     *
+     * @see kv::ReadableMapHandle::get_globally_committed
+     *
+     * @param key Key to test
+     *
+     * @return Boolean true iff key exists in globally committed state
+     */
+    bool contains_globally_committed(const K& key)
+    {
+      return read_handle.has_globally_committed(
+        KSerialiser::to_serialised(key));
+    }
+
     /** Get version when this key was last added to the set.
      *
      * Returns nullopt if the key is not present.

include/ccf/kv/untyped_map_handle.h

@@ -57,6 +57,8 @@ namespace kv::untyped
 
     bool has(const KeyType& key);
 
+    bool has_globally_committed(const KeyType& key);
+
     void put(const KeyType& key, const ValueType& value);
 
     void remove(const KeyType& key);

src/kv/test/kv_test.cpp

@@ -199,10 +199,16 @@ TEST_CASE("sets and values")
       REQUIRE(set_handle->contains(k2));
       REQUIRE(set_handle->size() == 2);
 
+      REQUIRE(!set_handle->contains_globally_committed(k1));
+      REQUIRE(!set_handle->contains_globally_committed(k2));
+
       set_handle->remove(k2);
       REQUIRE(!set_handle->contains(k2));
       REQUIRE(set_handle->size() == 1);
 
+      REQUIRE(!set_handle->contains_globally_committed(k1));
+      REQUIRE(!set_handle->contains_globally_committed(k2));
+
       REQUIRE(tx.commit() == kv::CommitResult::SUCCESS);
     }
 
@@ -212,6 +218,11 @@ TEST_CASE("sets and values")
       auto set_handle = tx.ro(set);
       REQUIRE(set_handle->contains(k1));
       REQUIRE(!set_handle->contains(k2));
+
+      // NB: Previous transaction committed locally, but not yet globally
+      REQUIRE(!set_handle->contains_globally_committed(k1));
+      REQUIRE(!set_handle->contains_globally_committed(k2));
+
       REQUIRE(set_handle->size() == 1);
       std::set<std::string> std_set;
       set_handle->foreach([&std_set](const std::string& entry) {
@@ -224,6 +235,26 @@ TEST_CASE("sets and values")
       REQUIRE(tx.commit() == kv::CommitResult::SUCCESS);
     }
 
+    {
+      INFO("Read committed writes");
+      kv_store.compact(kv_store.current_version());
+
+      auto tx = kv_store.create_tx();
+      auto set_handle = tx.rw(set);
+
+      REQUIRE(set_handle->contains_globally_committed(k1));
+      REQUIRE(!set_handle->contains_globally_committed(k2));
+
+      // Local modifications do not affect globally_committed
+      set_handle->remove(k1);
+      set_handle->insert(k2);
+
+      REQUIRE(set_handle->contains_globally_committed(k1));
+      REQUIRE(!set_handle->contains_globally_committed(k2));
+
+      // This tx is deliberately dropped, not committed
+    }
+
     {
       INFO("Remove keys");
       auto tx = kv_store.create_tx();
@@ -240,9 +271,32 @@ TEST_CASE("sets and values")
       REQUIRE(!set_handle->contains(k1));
       REQUIRE(set_handle->size() == 0);
 
+      // Not even locally committed, so globally_committed is unaffected
+      REQUIRE(set_handle->contains_globally_committed(k1));
+      REQUIRE(!set_handle->contains_globally_committed(k2));
+
       REQUIRE(tx.commit() == kv::CommitResult::SUCCESS);
     }
 
+    {
+      INFO("Read committed removals");
+      {
+        auto tx = kv_store.create_tx();
+        auto set_handle = tx.ro(set);
+        // Removal is still only locally committed
+        REQUIRE(set_handle->contains_globally_committed(k1));
+        REQUIRE(!set_handle->contains_globally_committed(k2));
+      }
+      kv_store.compact(kv_store.current_version());
+      {
+        auto tx = kv_store.create_tx();
+        auto set_handle = tx.ro(set);
+        // Removal is now globally committed
+        REQUIRE(!set_handle->contains_globally_committed(k1));
+        REQUIRE(!set_handle->contains_globally_committed(k2));
+      }
+    }
+
     {
       INFO("Hooks");
 

src/kv/untyped_map_handle.cpp

@@ -153,6 +153,12 @@ namespace kv::untyped
     return found;
   }
 
+  bool MapHandle::has_globally_committed(const MapHandle::KeyType& key)
+  {
+    auto raw = tx_changes.committed.getp(key);
+    return raw != nullptr;
+  }
+
   void MapHandle::put(
     const MapHandle::KeyType& key, const MapHandle::ValueType& value)
   {