Implement background expiry

mleleszi · Jun 14, 2024 · a71c389 · a71c389
1 parent b9121d9
commit a71c389
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Showing 3 changed files with 41 additions and 1 deletion.
diff --git a/src/controller.h b/src/controller.h
@@ -5,6 +5,8 @@
 
 class Controller {
 public:
+    Controller() { dataStore.startExpiryDaemon(); }
+
     RedisType::RedisValue handleCommand(const std::vector<RedisType::BulkString> &command);
 
 private:
@@ -14,6 +16,6 @@ class Controller {
     RedisType::RedisValue handleGet(const std::vector<RedisType::BulkString> &command);
     RedisType::RedisValue handleExists(const std::vector<RedisType::BulkString> &command);
     RedisType::RedisValue handleConfig(const std::vector<RedisType::BulkString> &command);
-    
+
     DataStore dataStore;
 };
diff --git a/src/datastore.h b/src/datastore.h
@@ -6,6 +6,7 @@
 #include <optional>
 #include <random>
 #include <string>
+#include <thread>
 #include <unordered_map>
 #include <vector>
 
@@ -65,6 +66,22 @@ class DataStore {
         return deleted;
     }
 
+    void startExpiryDaemon() {
+        auto backgroundThread = [this]() {
+            while (true) {
+                std::this_thread::sleep_for(std::chrono::milliseconds(100));
+                removeExpiredKeys();
+            }
+        };
+
+        std::thread(backgroundThread).detach();
+    }
+
+    int count() {
+        std::lock_guard<std::mutex> lock(mtx);
+        return store.size();
+    }
+
 
 private:
     std::unordered_map<std::string, Entry> store;

diff --git a/tests/datastore_test.cpp b/tests/datastore_test.cpp
@@ -44,6 +44,27 @@ TEST(DataStoreTests, RemoveExpiredKeys) {
     auto val1 = store.get("key1");
     ASSERT_FALSE(val1.has_value());
 
+    auto val2 = store.get("key2");
+    ASSERT_FALSE(val2.has_value());
+}
+
+TEST(DataStoreTests, ExpiryDaemon) {
+    DataStore store;
+    store.startExpiryDaemon();
+
+    store.setWithExpiry("key0", "val0", std::chrono::system_clock::now() + std::chrono::milliseconds(1000));
+    store.setWithExpiry("key1", "val1", std::chrono::system_clock::now() + std::chrono::milliseconds(200));
+    store.setWithExpiry("key2", "val2", std::chrono::system_clock::now() + std::chrono::milliseconds(300));
+    store.set("key3", "val3");
+
+    std::this_thread::sleep_for(std::chrono::milliseconds(500));
+
+    auto count = store.count();
+    ASSERT_EQ(count, 2);
+
+    auto val1 = store.get("key1");
+    ASSERT_FALSE(val1.has_value());
+
     auto val2 = store.get("key2");
     ASSERT_FALSE(val2.has_value());
 }