feat(framework): Add startup update checks for flwr

framework/py/flwr/cli/app.py

@@ -20,6 +20,7 @@
 import typer
 from typer.main import get_command
 
+from flwr.supercore.update_check import warn_if_flwr_update_available
 from flwr.supercore.version import package_version
 
 from .app_cmd import publish as app_publish
@@ -147,6 +148,8 @@ def main(
     ),
 ) -> None:
     """Flower CLI."""
+    warn_if_flwr_update_available(process_name="flwr")
+
     if version:
         typer.secho(f"Flower version: {package_version}", fg="blue")
         raise typer.Exit()

framework/py/flwr/cli/cli_test.py

@@ -15,30 +15,40 @@
 """Tests for the CLI."""
 
 
+from typing import Any
+from unittest.mock import patch
+
+import pytest
 from typer.testing import CliRunner
 
 from flwr.supercore.version import package_version
 
+from . import app as app_module
 from .app import app
 
 runner = CliRunner()
 
 
+def _invoke_flwr(args: list[str]) -> Any:
+    with patch("flwr.cli.app.warn_if_flwr_update_available"):
+        return runner.invoke(app, args)
+
+
 def test_version_args() -> None:
     """Test the --version flag."""
-    result = runner.invoke(app, ["--version"])
+    result = _invoke_flwr(["--version"])
     assert result.exit_code == 0
     assert f"Flower version: {package_version}\n" in result.output
 
     # Test the -V flag
-    result = runner.invoke(app, ["-V"])
+    result = _invoke_flwr(["-V"])
     assert result.exit_code == 0
     assert f"Flower version: {package_version}\n" in result.output
 
 
 def test_help_command() -> None:
     """Test the -h flag."""
-    result = runner.invoke(app, ["-h"])
+    result = _invoke_flwr(["-h"])
     assert result.exit_code == 0
     assert "Usage:" in result.output
     assert "Options " in result.output
@@ -47,71 +57,92 @@ def test_help_command() -> None:
 
 def test_new_command() -> None:
     """Add appropriate assertions for the new command."""
-    result = runner.invoke(app, ["new", "--help"])
+    result = _invoke_flwr(["new", "--help"])
     assert result.exit_code == 0
     assert "Usage:" in result.output
     assert "new" in result.output
 
 
 def test_run_command() -> None:
     """Add appropriate assertions for the run command."""
-    result = runner.invoke(app, ["run", "--help"])
+    result = _invoke_flwr(["run", "--help"])
     assert result.exit_code == 0
     assert "Usage:" in result.output
     assert "run" in result.output
 
 
 def test_build_command() -> None:
     """Add appropriate assertions for the build command."""
-    result = runner.invoke(app, ["build", "--help"])
+    result = _invoke_flwr(["build", "--help"])
     assert result.exit_code == 0
     assert "Usage:" in result.output
     assert "build" in result.output
 
 
 def test_install_command() -> None:
     """Add appropriate assertions for the install command."""
-    result = runner.invoke(app, ["install", "--help"])
+    result = _invoke_flwr(["install", "--help"])
     assert result.exit_code == 0
     assert "Usage:" in result.output
     assert "install" in result.output
 
 
 def test_log_command() -> None:
     """Add appropriate assertions for the log command."""
-    result = runner.invoke(app, ["log", "--help"])
+    result = _invoke_flwr(["log", "--help"])
     assert result.exit_code == 0
     assert "Usage:" in result.output
     assert "log" in result.output
 
 
 def test_ls_command() -> None:
     """Add appropriate assertions for the ls command."""
-    result = runner.invoke(app, ["ls", "--help"])
+    result = _invoke_flwr(["ls", "--help"])
     assert result.exit_code == 0
     assert "Usage:" in result.output
     assert "ls" in result.output
 
 
 def test_stop_command() -> None:
     """Add appropriate assertions for the stop command."""
-    result = runner.invoke(app, ["stop", "--help"])
+    result = _invoke_flwr(["stop", "--help"])
     assert result.exit_code == 0
     assert "Usage:" in result.output
     assert "stop" in result.output
 
 
 def test_login_command() -> None:
     """Add appropriate assertions for the login command."""
-    result = runner.invoke(app, ["login", "--help"])
+    result = _invoke_flwr(["login", "--help"])
     assert result.exit_code == 0
     assert "Usage:" in result.output
     assert "login" in result.output
 
 
+def test_flwr_callback_checks_for_update(monkeypatch: pytest.MonkeyPatch) -> None:
+    """The top-level flwr callback should perform the startup update check."""
+
+    class _SentinelError(Exception):
+        pass
+
+    captured: dict[str, str] = {}
+
+    def _raise_sentinel(process_name: str | None = None) -> None:
+        if process_name is not None:
+            captured["process_name"] = process_name
+        raise _SentinelError()
+
+    monkeypatch.setattr(app_module, "warn_if_flwr_update_available", _raise_sentinel)
+
+    with pytest.raises(_SentinelError):
+        app_module.main(version=False)
+
+    assert captured == {"process_name": "flwr"}
+
+
 def test_invalid_command() -> None:
     """Test CLI behavior with invalid commands and arguments."""
     # Test unknown command
-    result = runner.invoke(app, ["nonexistent-command"])
+    result = _invoke_flwr(["nonexistent-command"])
     assert result.exit_code != 0
     assert "No such command" in result.output

framework/py/flwr/cli/local_superlink.py

@@ -17,6 +17,7 @@
 
 from __future__ import annotations
 
+import os
 import subprocess
 import time
 from pathlib import Path
@@ -27,6 +28,7 @@
 
 from flwr.common.constant import ISOLATION_MODE_SUBPROCESS
 from flwr.common.grpc import create_channel
+from flwr.supercore.constant import FLWR_DISABLE_UPDATE_CHECK
 from flwr.supercore.utils import get_flwr_home
 
 from .constant import (
@@ -126,8 +128,13 @@ def _start_local_superlink() -> None:
 
     # Keep process detached and rely on SuperLink's file logging/rotation.
     try:
+        env = os.environ.copy()
+        # NOTE: `flwr` already performs the startup update check before spawning this
+        # managed child process, so we disable the child-side check to avoid duplicates.
+        env[FLWR_DISABLE_UPDATE_CHECK] = "1"
         process = subprocess.Popen(  # pylint: disable=consider-using-with
             command,
+            env=env,
             stdout=subprocess.DEVNULL,
             stderr=subprocess.DEVNULL,
             start_new_session=True,

framework/py/flwr/cli/local_superlink_test.py

@@ -20,6 +20,7 @@
 from unittest.mock import MagicMock, patch
 
 from flwr.cli.typing import SuperLinkConnection, SuperLinkSimulationOptions
+from flwr.supercore.constant import FLWR_DISABLE_UPDATE_CHECK
 
 from .local_superlink import _start_local_superlink, ensure_local_superlink
 
@@ -111,3 +112,4 @@ def test_start_local_superlink_uses_builtin_log_rotation(tmp_path: Path) -> None
     assert "7" in cmd
     assert popen.call_args.kwargs["stdout"] is subprocess.DEVNULL
     assert popen.call_args.kwargs["stderr"] is subprocess.DEVNULL
+    assert popen.call_args.kwargs["env"][FLWR_DISABLE_UPDATE_CHECK] == "1"