[lordgamez]

Added nifi.c2.connection.timeout minifi property that triggers a graceful shutdown if set and the C2 connection is not established or lost for the specified time period.

Additionally to the automated tests, the feature was manually verified using Windows and Linux (systemd) MiNiFi services.

https://issues.apache.org/jira/browse/MINIFICPP-2933

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[Copilot]

🟡 Changes recommended

Unresolved watchdog timing and shutdown-coordination races can cause false timeout exits or restart the agent after a terminal shutdown request.

3 open issues

• Latch timeout shutdown against in-flight restart callbacks · New
• Cancel watchdog before waiting for C2 workers · New
• Read current time before heartbeat timestamp · New

What changed in this PR

Adds an opt-in C2 connection timeout that gracefully shuts down MiNiFi when successful heartbeats stop or never begin, with service handling to prevent automatic restart.

Changes:

• Introduces the connection watchdog, timeout configuration, and shutdown callback carrying exit code 90.
• Updates Windows and systemd service handling and documents the configuration.
• Adds unit, integration, and container scenarios covering timeout behavior.

File	Description
minifi-api/​include/​minifi-cpp/​properties/​Configuration.h	Declares the connection-timeout property.
minifi_main/​MiNiFiWindowsService.cpp	Prevents restart after timeout exit.
minifi_main/​MiNiFiMain.cpp	Handles shutdown requests and exit codes.
libminifi/​test/​unit/​C2ShutdownRecorder.h	Records shutdown callbacks for tests.
libminifi/​test/​unit/​C2ConnectionWatchdogTests.cpp	Tests watchdog timing and lifecycle.
libminifi/​test/​unit/​C2AgentWatchdogConfigurationTests.cpp	Tests timeout configuration and agent behavior.
libminifi/​test/​libtest/​integration/​IntegrationBase.h	Adds shutdown tracking fields.
libminifi/​test/​libtest/​integration/​IntegrationBase.cpp	Records shutdown requests in the harness.
libminifi/​test/​integration/​C2ConnectionTimeoutTest.cpp	Tests shutdown after heartbeat failures.
libminifi/​src/​FlowController.cpp	Passes shutdown callbacks to C2.
libminifi/​src/​Configuration.cpp	Registers timeout property validators.
libminifi/​src/​c2/​C2ConnectionWatchdog.cpp	Implements heartbeat timeout monitoring.
libminifi/​src/​c2/​C2Agent.cpp	Configures and manages the watchdog.
libminifi/​include/​RequestShutdown.h	Defines the shutdown callback contract.
libminifi/​include/​FlowController.h	Updates the controller callback interface.
libminifi/​include/​c2/​C2ExitCodes.h	Defines timeout exit code 90.
libminifi/​include/​c2/​C2ConnectionWatchdog.h	Declares watchdog state and heartbeat updates.
libminifi/​include/​c2/​C2Agent.h	Adds watchdog state and shutdown callback.
extensions/​standard-processors/​tests/​features/​steps/​steps.py	Adds server-stop and exit-code checks.
extensions/​standard-processors/​tests/​features/​minifi_c2_server.feature	Adds lost and unavailable connection scenarios.
conf/​minifi.properties.in	Adds a commented timeout example.
C2.md	Documents timeout and service behavior.
bin/​minifi.service.in	Prevents systemd restart for exit code 90.
behave_framework/​src/​minifi_behave/​steps/​checking_steps.py	Checks logs from exited containers.
behave_framework/​src/​minifi_behave/​containers/​container_windows.py	Exposes container exit codes on Windows.
behave_framework/​src/​minifi_behave/​containers/​container_protocol.py	Adds the exit-code interface.
behave_framework/​src/​minifi_behave/​containers/​container_linux.py	Exposes container exit codes on Linux.

_{Review effort: Balanced}