Fix Docker state drift: add 5s background state poller and make mutating operations idempotent (404/304 as success)

tests/test_docker_manager_idempotent.cpp

@@ -0,0 +1,136 @@
+#include "docker_manager.hpp"
+#include "docker_engine_client.hpp"
+
+#include <cassert>
+#include <iostream>
+#include <memory>
+#include <string>
+
+class MockEngineClient : public DockerEngineClient {
+public:
+    mutable std::string last_method;
+    mutable std::string last_path;
+    EngineResponse response;
+
+    EngineResponse request(const std::string& method,
+                           const std::string& path,
+                           const std::string& /*body*/ = {},
+                           int /*timeout_seconds*/ = 10) const override {
+        last_method = method;
+        last_path = path;
+        return response;
+    }
+};
+
+static std::unique_ptr<MockEngineClient> make_engine(const EngineResponse& response) {
+    auto engine = std::make_unique<MockEngineClient>();
+    engine->response = response;
+    return engine;
+}
+
+void test_start_detached() {
+    {
+        auto engine = make_engine(EngineResponse{204, {}, {}});
+        auto* raw = engine.get();
+        DockerManager manager(std::move(engine));
+        std::string message;
+        assert(manager.startDetached("abc123", message));
+        assert(message == "Container started in detached mode.");
+        assert(raw->last_method == "POST");
+        assert(raw->last_path == "/containers/abc123/start");
+    }
+    {
+        auto engine = make_engine(EngineResponse{304, {}, {}});
+        DockerManager manager(std::move(engine));
+        std::string message;
+        assert(manager.startDetached("abc123", message));
+        assert(message == "Container already started.");
+    }
+    {
+        auto engine = make_engine(EngineResponse{500, {}, "engine error"});
+        DockerManager manager(std::move(engine));
+        std::string message;
+        assert(!manager.startDetached("abc123", message));
+        assert(message == "engine error");
+    }
+}
+
+void test_remove_container() {
+    {
+        auto engine = make_engine(EngineResponse{204, {}, {}});
+        DockerManager manager(std::move(engine));
+        std::string message;
+        assert(manager.removeContainer("abc123", message));
+        assert(message == "Container removed.");
+    }
+    {
+        auto engine = make_engine(EngineResponse{404, {}, "No such container"});
+        DockerManager manager(std::move(engine));
+        std::string message;
+        assert(manager.removeContainer("abc123", message));
+        assert(message == "Container already removed.");
+    }
+    {
+        auto engine = make_engine(EngineResponse{409, {}, "conflict"});
+        DockerManager manager(std::move(engine));
+        std::string message;
+        assert(!manager.removeContainer("abc123", message));
+        assert(message == "conflict");
+    }
+}
+
+void test_delete_image() {
+    {
+        auto engine = make_engine(EngineResponse{200, {}, {}});
+        DockerManager manager(std::move(engine));
+        std::string message;
+        assert(manager.deleteImage("sha256:abc", message));
+        assert(message == "Image deleted.");
+    }
+    {
+        auto engine = make_engine(EngineResponse{404, {}, "No such image"});
+        DockerManager manager(std::move(engine));
+        std::string message;
+        assert(manager.deleteImage("sha256:abc", message));
+        assert(message == "Image already deleted.");
+    }
+    {
+        auto engine = make_engine(EngineResponse{409, {}, "image in use"});
+        DockerManager manager(std::move(engine));
+        std::string message;
+        assert(!manager.deleteImage("sha256:abc", message));
+        assert(message == "image in use");
+    }
+}
+
+void test_stop_container() {
+    {
+        auto engine = make_engine(EngineResponse{204, {}, {}});
+        DockerManager manager(std::move(engine));
+        std::string message;
+        assert(manager.stopContainer("abc123", message, 10));
+        assert(message == "Container stopped.");
+    }
+    {
+        auto engine = make_engine(EngineResponse{304, {}, {}});
+        DockerManager manager(std::move(engine));
+        std::string message;
+        assert(manager.stopContainer("abc123", message, 10));
+        assert(message == "Container stopped.");
+    }
+    {
+        auto engine = make_engine(EngineResponse{404, {}, "No such container"});
+        DockerManager manager(std::move(engine));
+        std::string message;
+        assert(manager.stopContainer("abc123", message, 10));
+        assert(message == "Container stopped.");
+    }
+}
+
+int main() {
+    test_start_detached();
+    test_remove_container();
+    test_delete_image();
+    test_stop_container();
+    std::cout << "Docker manager idempotent operation tests passed\n";
+}