build: pin and verify image inputs

tests/unit/test_docker_util_image.py

@@ -121,5 +121,54 @@ class TestCommitContainer(unittest.TestCase):
         self.assertIn("my-tag:v1", die.call_args.args[0])
 
 
+class TestBuildImage(unittest.TestCase):
+    def test_passes_build_args_without_mutating_the_value(self):
+        with patch.object(
+            docker_mod.subprocess, "run", return_value=_ok(),
+        ) as run, patch.object(docker_mod, "info"):
+            docker_mod.build_image(
+                "derived:test",
+                "/context",
+                dockerfile="Dockerfile.derived",
+                build_args={"BASE_IMAGE": "sha256:" + "a" * 64},
+            )
+        self.assertEqual(
+            [
+                "docker", "build", "-t", "derived:test",
+                "-f", "Dockerfile.derived",
+                "--build-arg", "BASE_IMAGE=sha256:" + "a" * 64,
+                "/context",
+            ],
+            run.call_args.args[0],
+        )
+
+
+class TestImageId(unittest.TestCase):
+    def test_returns_content_addressed_local_id(self):
+        expected = "sha256:" + "b" * 64
+        with patch.object(
+            docker_mod, "run_docker", return_value=_ok(stdout=expected + "\n"),
+        ) as run:
+            self.assertEqual(expected, docker_mod.image_id("base:mutable"))
+        self.assertEqual(
+            [
+                "docker", "image", "inspect", "--format", "{{.Id}}",
+                "base:mutable",
+            ],
+            run.call_args.args[0],
+        )
+
+    def test_rejects_failed_or_non_content_addressed_inspect(self):
+        for result in (_fail("missing"), _ok(stdout="base:latest\n")):
+            with self.subTest(result=result), patch.object(
+                docker_mod, "run_docker", return_value=result,
+            ), patch.object(
+                docker_mod, "die", side_effect=SystemExit("die"),
+            ) as die:
+                with self.assertRaises(SystemExit):
+                    docker_mod.image_id("base:latest")
+                die.assert_called_once()
+
+
 if __name__ == "__main__":
     unittest.main()

tests/unit/test_firecracker_infra_vm.py

@@ -107,7 +107,12 @@ class TestEnsureBuilt(unittest.TestCase):
 
     def test_local_mode_builds_orchestrator_before_its_fc_image(self):
         with patch.dict(os.environ, {"BOT_BOTTLE_INFRA_BUILD": "local"}), \
-                patch.object(infra_vm.docker_mod, "build_image") as build:
+                patch.object(infra_vm.docker_mod, "build_image") as build, \
+                patch.object(
+                    infra_vm.docker_mod,
+                    "image_id",
+                    return_value="sha256:" + "a" * 64,
+                ) as image_id:
             infra_vm.ensure_built()
         tags = [c.args[0] for c in build.call_args_list]
         # orchestrator-fc is FROM orchestrator, so the base is built first.
@@ -116,6 +121,11 @@ class TestEnsureBuilt(unittest.TestCase):
         self.assertEqual(infra_vm._ORCHESTRATOR_FC_IMAGE, tags[-1])
         self.assertLess(tags.index(infra_vm._ORCHESTRATOR_IMAGE),
                         tags.index(infra_vm._ORCHESTRATOR_FC_IMAGE))
+        image_id.assert_called_once_with(infra_vm._ORCHESTRATOR_IMAGE)
+        self.assertEqual(
+            {"ORCHESTRATOR_BASE_IMAGE": "sha256:" + "a" * 64},
+            build.call_args_list[-1].kwargs["build_args"],
+        )
 
 
 class TestStop(unittest.TestCase):

tests/unit/test_infra_artifact.py

@@ -110,6 +110,7 @@ class TestVersionInputs(unittest.TestCase):
         for name in ("Dockerfile.orchestrator", "Dockerfile.orchestrator.fc",
                      "Dockerfile.gateway"):
             (root / name).write_text(f"FROM scratch  # {name}\n")
+        (root / "requirements.gateway.lock").write_text("mitmproxy==11.1.3\n")
         (root / "pyproject.toml").write_text("[project]\nname = 'bot-bottle'\n")
 
     def test_pyproject_toml_change_bumps_version(self) -> None:
@@ -146,6 +147,21 @@ class TestVersionInputs(unittest.TestCase):
             after = ia.infra_artifact_version("init", _ROLE, repo_root=root)
         self.assertNotEqual(before, after)
 
+    def test_gateway_lock_change_bumps_gateway_version(self) -> None:
+        with tempfile.TemporaryDirectory() as d:
+            root = Path(d)
+            self._fake_repo(root)
+            before = ia.infra_artifact_version(
+                "init", "gateway", repo_root=root,
+            )
+            (root / "requirements.gateway.lock").write_text(
+                "mitmproxy==11.1.3 --hash=sha256:changed\n",
+            )
+            after = ia.infra_artifact_version(
+                "init", "gateway", repo_root=root,
+            )
+        self.assertNotEqual(before, after)
+
     def test_pyc_and_pycache_ignored(self) -> None:
         with tempfile.TemporaryDirectory() as d:
             root = Path(d)