Add --local (-L) for --consistency-only and --predict-only options

CHANGES.d/20241118_043939_elikowa_add_check_and_predict_local_flag.md

@@ -0,0 +1,4 @@
+- Adds a `--local` flag to `./batou deploy`, which can
+  be used in tandem with `--consistency-only` or `--predict-only` to
+  check and predict using the local host's state, without connecting to
+  the remote host.

doc/source/cli/index.txt

@@ -30,7 +30,9 @@ batou deploy
 
 .. code-block:: console
 
-  usage: batou deploy [-h] [-p PLATFORM] [-t TIMEOUT] [-D] [-c] [-P] [-j JOBS]
+  usage: batou deploy [-h] [-p PLATFORM] [-t TIMEOUT] [-D] [-c] [-P]
+                      [--local] [-j JOBS]
+                      [--provision-rebuild]
                       environment
 
   positional arguments:
@@ -50,6 +52,9 @@ batou deploy
                           Does not touch anything.
     -P, --predict-only    Only predict what updates would happen. Do not change
                           anything.
+    -L, --local           When running in consistency-only or predict-only mode,
+                          do not connect to the remote host, but check and
+                          predict using the local host's state.
     -j JOBS, --jobs JOBS  Defines number of jobs running parallel to deploy. The
                           default results in a serial deployment of components.
                           Will override the environment settings for operational

src/batou/deploy.py

@@ -112,10 +112,15 @@ def __init__(
         dirty,
         jobs,
         predict_only=False,
+        check_and_predict_local=False,
         provision_rebuild=False,
     ):
         self.environment = Environment(
-            environment, timeout, platform, provision_rebuild=provision_rebuild
+            environment,
+            timeout,
+            platform,
+            provision_rebuild=provision_rebuild,
+            check_and_predict_local=check_and_predict_local,
         )
         self.environment.deployment = self
 
@@ -345,6 +350,7 @@ def main(
     dirty,
     consistency_only,
     predict_only,
+    check_and_predict_local,
     jobs,
     provision_rebuild,
 ):
@@ -361,6 +367,14 @@ def main(
     else:
         ACTION = "DEPLOYMENT"
         SUCCESS_FORMAT = {"green": True}
+    if check_and_predict_local:
+        if (not consistency_only) and (not predict_only):
+            output.error(
+                "The --local option is only to be used with --consistency-only or --predict-only."
+            )
+            sys.exit(1)
+        ACTION += " (local)"
+
     with locked(".batou-lock", exit_on_failure=True):
         deployment = Deployment(
             environment,
@@ -369,6 +383,7 @@ def main(
             dirty,
             jobs,
             predict_only,
+            check_and_predict_local,
             provision_rebuild,
         )
         environment = deployment.environment

src/batou/environment.py

@@ -130,6 +130,7 @@ def __init__(
         platform=None,
         basedir=".",
         provision_rebuild=False,
+        check_and_predict_local=False,
     ):
         self.name: str = name
         self.hosts: Dict[str, Host] = {}
@@ -140,6 +141,7 @@ def __init__(
         self.timeout = timeout
         self.platform = platform
         self.provision_rebuild = provision_rebuild
+        self.check_and_predict_local = check_and_predict_local
 
         self.hostname_mapping: Dict[str, str] = {}
 
@@ -291,6 +293,9 @@ def load_environment(self, config):
 
         self._set_defaults()
 
+        if self.check_and_predict_local:
+            self.connect_method = "local"
+
         if "vfs" in config:
             sandbox = config["vfs"]["sandbox"]
             sandbox = getattr(batou.vfs, sandbox)(self, config["vfs"])

src/batou/main.py

@@ -76,6 +76,15 @@ def main(args: Optional[list] = None) -> None:
         help="Only predict what updates would happen. "
         "Do not change anything.",
     )
+    p.add_argument(
+        "-L",
+        "--local",
+        action="store_true",
+        dest="check_and_predict_local",
+        help="When running in consistency-only or predict-only mode, "
+        "do not connect to the remote host, but check and predict "
+        "using the local host's state.",
+    )
     p.add_argument(
         "-j",
         "--jobs",

src/batou/tests/test_deploy.py

@@ -18,6 +18,7 @@ def test_main_with_errors(capsys):
             dirty=False,
             consistency_only=False,
             predict_only=False,
+            check_and_predict_local=False,
             jobs=None,
             provision_rebuild=False,
         )
@@ -81,6 +82,7 @@ def test_main_fails_if_no_host_in_environment(capsys):
             dirty=False,
             consistency_only=False,
             predict_only=False,
+            check_and_predict_local=False,
             jobs=None,
             provision_rebuild=False,
         )

src/batou/tests/test_endtoend.py

@@ -372,3 +372,116 @@ def test_durations_are_shown_for_components():
 ============================= DEPLOYMENT FINISHED ==============================
 """
     )
+
+
+def test_check_consistency_works():
+    os.chdir("examples/tutorial-secrets")
+    out, _ = cmd("./batou deploy tutorial --consistency-only")
+    assert out == Ellipsis(
+        """\
+batou/2... (cpython 3...)
+================================== Preparing ===================================
+main: Loading environment `tutorial`...
+main: Verifying repository ...
+main: Loading secrets ...
+================== Connecting hosts and configuring model ... ==================
+localhost: Connecting via local (1/1)
+=================================== Summary ====================================
+Deployment took total=...s, connect=...s, deploy=NaN
+========================== CONSISTENCY CHECK FINISHED ==========================
+"""
+    )
+
+
+def test_predicting_deployment_works():
+    os.chdir("examples/tutorial-secrets")
+    out, _ = cmd("./batou deploy tutorial --predict-only")
+    assert out == Ellipsis(
+        """\
+batou/2... (cpython 3...)
+================================== Preparing ===================================
+main: Loading environment `tutorial`...
+main: Verifying repository ...
+main: Loading secrets ...
+================== Connecting hosts and configuring model ... ==================
+localhost: Connecting via local (1/1)
+======================== Predicting deployment actions =========================
+localhost: Scheduling component hello ...
+localhost > Hello > File('work/hello/hello') > Presence('hello')
+localhost > Hello > File('work/hello/hello') > Content('hello')
+Not showing diff as it contains sensitive data,
+see .../examples/tutorial-secrets/work/.batou-diffs/...diff for the diff.
+localhost > Hello > File('work/hello/other-secrets.yaml') > Presence('other-secrets.yaml')
+localhost > Hello > File('work/hello/other-secrets.yaml') > Content('other-secrets.yaml')
+Not showing diff as it contains sensitive data,
+see .../examples/tutorial-secrets/work/.batou-diffs/...diff for the diff.
+=================================== Summary ====================================
+Deployment took total=...s, connect=...s, deploy=...s
+======================== DEPLOYMENT PREDICTION FINISHED ========================
+"""
+    )
+
+
+def test_check_consistency_works_with_local():
+    os.chdir("examples/tutorial-secrets")
+    out, _ = cmd("./batou deploy gocept --consistency-only --local")
+    assert out == Ellipsis(
+        """\
+batou/2... (cpython 3...)
+================================== Preparing ===================================
+main: Loading environment `gocept`...
+main: Verifying repository ...
+main: Loading secrets ...
+================== Connecting hosts and configuring model ... ==================
+test01: Connecting via local (1/2)
+test02: Connecting via local (2/2)
+=================================== Summary ====================================
+Deployment took total=...s, connect=...s, deploy=NaN
+====================== CONSISTENCY CHECK (local) FINISHED ======================
+"""
+    )
+
+
+def test_predicting_deployment_works_with_local():
+    os.chdir("examples/tutorial-secrets")
+    out, _ = cmd("./batou deploy gocept --predict-only --local")
+    assert out == Ellipsis(
+        """\
+batou/2... (cpython 3...)
+================================== Preparing ===================================
+main: Loading environment `gocept`...
+main: Verifying repository ...
+main: Loading secrets ...
+================== Connecting hosts and configuring model ... ==================
+test01: Connecting via local (1/2)
+test02: Connecting via local (2/2)
+======================== Predicting deployment actions =========================
+test01: Scheduling component hello ...
+test02: Scheduling component hello ...
+test01 > Hello > File('work/hello/hello') > Presence('hello')
+test01 > Hello > File('work/hello/hello') > Content('hello')
+  hello ---
+  hello +++
+  hello @@ -0,0 +1,2 @@
+  hello +The magic word is None.
+  hello +The other word is None.
+test01 > Hello > File('work/hello/other-secrets.yaml') > Presence('other-secrets.yaml')
+test01 > Hello > File('work/hello/other-secrets.yaml') > Content('other-secrets.yaml')
+Not showing diff as it contains sensitive data,
+see .../batou/examples/tutorial-secrets/work/.batou-diffs/...diff for the diff.
+test02 > Hello > File('work/hello/hello') > Presence('hello')
+test02 > Hello > File('work/hello/hello') > Content('hello')
+  hello ---
+  hello +++
+  hello @@ -0,0 +1,2 @@
+  hello +The magic word is None.
+  hello +The other word is None.
+test02 > Hello > File('work/hello/other-secrets.yaml') > Presence('other-secrets.yaml')
+test02 > Hello > File('work/hello/other-secrets.yaml') > Content('other-secrets.yaml')
+Not showing diff as it contains sensitive data,
+see .../batou/examples/tutorial-secrets/work/.batou-diffs/...diff for the diff.
+=================================== Summary ====================================
+Deployment took total=...s, connect=...s, deploy=...s
+==================== DEPLOYMENT PREDICTION (local) FINISHED ====================
+"""
+    )