Define a single source of version information

.pylintrc

@@ -42,11 +42,12 @@ confidence=
 enable=all
 
 # Disable the message, report, category or checker with the given ID(s).
-disable=abstract-method,    # Too many false positive :/
-        bad-whitespace,     # Alignment is a good thing.
-        bad-continuation,   # I kindly disagree :)
-        locally-disabled,   # Sometime we need to disable a warning locally.
-        suppressed-message  # Don't pollute the output with useless info.
+disable=abstract-method,     # Too many false positive :/
+        bad-whitespace,      # Alignment is a good thing.
+        bad-continuation,    # I kindly disagree :)
+        locally-disabled,    # Sometime we need to disable a warning locally.
+        suppressed-message,  # Don't pollute the output with useless info.
+        useless-return       # Disagreement with mypy, see https://github.com/python/mypy/issues/3974
 
 # }}}
 # Basic {{{

buildchain/buildchain/constants.py

@@ -46,44 +46,7 @@
 VAGRANT_SSH_KEY_PAIR : Path = VAGRANT_ROOT/'preshared_key_for_k8s_nodes'
 
 # }}}
-# Versions {{{
-
-K8S_VERSION  : str = '1.11.10'
-SALT_VERSION : str = '2018.3.4'
-KEEPALIVED_VERSION : str = '1.3.5-8.el7_6'
-KEEPALIVED_BUILD_ID : int = 1
-
-CENTOS_BASE_IMAGE : str = 'docker.io/centos'
-CENTOS_BASE_IMAGE_SHA256 : str = \
-    '6ae4cddb2b37f889afd576a17a5286b311dcbf10a904409670827f6f9b50065e'
-
-def load_version_information() -> None:
-    """Load version information from `VERSION`."""
-    to_update = {
-        'VERSION_MAJOR', 'VERSION_MINOR', 'VERSION_PATCH', 'VERSION_SUFFIX'
-    }
-    with VERSION_FILE.open('r', encoding='utf-8') as fp:
-        for line in fp:
-            name, _, value = line.strip().partition('=')
-            # Don't overwrite random variables by trusting an external file.
-            var = name.strip()
-            if var in to_update:
-                globals()[var] = value.strip()
-
-
-VERSION_FILE : Path= ROOT/'VERSION'
-
-# Metalk8s version.
-# (Those declarations are not mandatory, but they help pylint and mypy).
-VERSION_MAJOR  : str
-VERSION_MINOR  : str
-VERSION_PATCH  : str
-VERSION_SUFFIX : str
-
-load_version_information()
-
-SHORT_VERSION : str = '{}.{}'.format(VERSION_MAJOR, VERSION_MINOR)
-VERSION : str = '{}.{}{}'.format(SHORT_VERSION, VERSION_PATCH, VERSION_SUFFIX)
+# Git project information {{{
 
 
 def git_ref() -> Optional[str]:

buildchain/buildchain/docker_command.py

@@ -141,13 +141,14 @@ def __init__(
     @task_error(docker.errors.BuildError, handler=build_error_handler)
     @task_error(docker.errors.APIError)
     def __call__(self) -> Optional[TaskError]:
-        return DOCKER_CLIENT.images.build(
+        DOCKER_CLIENT.images.build(
             tag=self.tag,
             path=self.path,
             dockerfile=self.dockerfile,
             buildargs=self.buildargs,
             forcerm=True,
         )
+        return None
 
 
 class DockerRun:
@@ -267,11 +268,12 @@ def expand_config(self) -> Dict[str, Any]:
     @task_error(docker.errors.APIError)
     def __call__(self) -> Optional[TaskError]:
         run_config = self.expand_config()
-        return DOCKER_CLIENT.containers.run(
+        DOCKER_CLIENT.containers.run(
             image=self.builder.tag,
             command=self.command,
             **run_config
         )
+        return None
 
 
 class DockerTag:
@@ -294,27 +296,42 @@ def __init__(self, repository: str, full_name: str, version: str):
     @task_error(docker.errors.APIError)
     def __call__(self) -> Optional[TaskError]:
         to_tag = DOCKER_CLIENT.images.get(self.full_name)
-        return to_tag.tag(self.repository, tag=self.version)
+        to_tag.tag(self.repository, tag=self.version)
+        return None
 
 
 class DockerPull:
     # The call method is not counted as a public method
     # pylint: disable=too-few-public-methods
     """A class to expose the `docker pull` command through the API client."""
 
-    def __init__(self, repository: str, digest: str):
+    def __init__(
+        self, repository: str, tag: str, digest: str
+    ):
         """Initialize a `docker pull` callable object.
          Arguments:
             repository: the repository to pull from
-            digest:     the digest to pull from the repository
+            tag:        the image tag to pull from the repository
+            digest:     the expected digest of the image to pull
         """
         self.repository = repository
+        self.tag = tag
         self.digest = digest
 
     @task_error(docker.errors.BuildError, handler=build_error_handler)
     @task_error(docker.errors.APIError)
     def __call__(self) -> Optional[TaskError]:
-        return DOCKER_CLIENT.images.pull(self.repository, tag=self.digest)
+        pulled = DOCKER_CLIENT.images.pull(self.repository, tag=self.tag)
+
+        if pulled.id != self.digest:
+            return TaskError(
+                "Image {} pulled from {} doesn't match expected digest: "
+                "expected {}, got {}".format(
+                    self.tag, self.repository, self.digest, pulled.id
+                )
+            )
+
+        return None
 
 
 class DockerSave:
@@ -336,7 +353,9 @@ def __init__(self, tag: str, save_path: Path):
     def __call__(self) -> Optional[TaskError]:
         to_save = DOCKER_CLIENT.images.get(self.tag)
         image_stream = to_save.save(named=True)
+
         with self.save_path.open('wb') as image_file:
             for chunk in image_stream:
                 image_file.write(chunk)
-        return True
+
+        return None

buildchain/buildchain/iso.py

@@ -40,6 +40,7 @@
 from buildchain import targets as helper
 from buildchain import types
 from buildchain import utils
+from buildchain import versions
 
 
 ISO_FILE : Path = config.BUILD_ROOT/'{}.iso'.format(config.PROJECT_NAME.lower())
@@ -148,8 +149,8 @@ def task__iso_render_bootstrap() -> types.TaskDict:
     return helper.TemplateFile(
         source=constants.ROOT/'scripts'/'bootstrap.sh.in',
         destination=constants.ISO_ROOT/'bootstrap.sh',
-        context={'VERSION': constants.VERSION},
-        file_dep=[constants.VERSION_FILE],
+        context={'VERSION': versions.VERSION},
+        file_dep=[versions.VERSION_FILE],
         task_dep=['_iso_mkdir_root'],
     ).task
 
@@ -158,11 +159,11 @@ def task__iso_generate_product_txt() -> types.TaskDict:
     """Generate the product.txt file."""
     def action(targets: Sequence[str]) -> None:
         datefmt = "%Y-%m-%dT%H:%M:%SZ"
-        dev_release = '1' if constants.VERSION_SUFFIX == '-dev' else '0'
+        dev_release = '1' if versions.VERSION_SUFFIX == '-dev' else '0'
         info = (
             ('NAME', config.PROJECT_NAME),
-            ('VERSION', constants.VERSION),
-            ('SHORT_VERSION', constants.SHORT_VERSION),
+            ('VERSION', versions.VERSION),
+            ('SHORT_VERSION', versions.SHORT_VERSION),
             ('GIT', constants.GIT_REF or ''),
             ('DEVELOPMENT_RELEASE', dev_release),
             ('BUILD_TIMESTAMP', dt.datetime.utcnow().strftime(datefmt)),
@@ -177,7 +178,7 @@ def action(targets: Sequence[str]) -> None:
         'title': lambda task: utils.title_with_target1('GENERATE', task),
         'actions': [action],
         'targets': [constants.ISO_ROOT/'product.txt'],
-        'file_dep': [constants.VERSION_FILE],
+        'file_dep': [versions.VERSION_FILE],
         'task_dep': ['_iso_mkdir_root'],
         'uptodate': [False],  # False because we include the build timestamp.
         'clean': True,
@@ -194,7 +195,7 @@ def task__iso_build() -> types.TaskDict:
         '-joliet',
         '-joliet-long',
         '-full-iso9660-filenames',
-        '-volid', '{} {}'.format(config.PROJECT_NAME, constants.VERSION),
+        '-volid', '{} {}'.format(config.PROJECT_NAME, versions.VERSION),
         '--iso-level', '3',
         '-gid', '0',
         '-uid', '0',
@@ -207,7 +208,7 @@ def task__iso_build() -> types.TaskDict:
     )
     # Every file used for the ISO is a dependency.
     depends = list(coreutils.ls_files_rec(constants.ISO_ROOT))
-    depends.append(constants.VERSION_FILE)
+    depends.append(versions.VERSION_FILE)
     return {
         'title': lambda task: utils.title_with_target1('MKISOFS', task),
         'doc': doc,

buildchain/buildchain/salt_tree.py

@@ -163,8 +163,8 @@ def _run(self) -> None:
         task_name='top.sls',
         source=constants.ROOT/'pillar'/'top.sls.in',
         destination=constants.ISO_ROOT/'pillar'/'top.sls',
-        context={'VERSION': constants.VERSION},
-        file_dep=[constants.VERSION_FILE],
+        context={'VERSION': versions.VERSION},
+        file_dep=[versions.VERSION_FILE],
     ),
 )
 
@@ -175,8 +175,8 @@ def _run(self) -> None:
         task_name='top.sls',
         source=constants.ROOT/'salt'/'top.sls.in',
         destination=constants.ISO_ROOT/'salt'/'top.sls',
-        context={'VERSION': constants.VERSION},
-        file_dep=[constants.VERSION_FILE],
+        context={'VERSION': versions.VERSION},
+        file_dep=[versions.VERSION_FILE],
     ),
 
     Path('salt/metalk8s/addons/monitoring/alertmanager/deployed.sls'),
@@ -207,8 +207,8 @@ def _run(self) -> None:
             'salt', 'metalk8s', 'addons', 'ui', 'files',
             'metalk8s-ui-deployment.yaml'
         ),
-        context={'VERSION': constants.VERSION},
-        file_dep=[constants.VERSION_FILE],
+        context={'VERSION': versions.VERSION},
+        file_dep=[versions.VERSION_FILE],
     ),
     Path('salt/metalk8s/addons/ui/precheck.sls'),
 
@@ -312,8 +312,8 @@ def _run(self) -> None:
             'salt', 'metalk8s', 'kubernetes', 'mark-control-plane',
             'deployed.sls'
         ),
-        context={'VERSION': constants.VERSION},
-        file_dep=[constants.VERSION_FILE],
+        context={'VERSION': versions.VERSION},
+        file_dep=[versions.VERSION_FILE],
     ),
 
     Path('salt/metalk8s/kubernetes/sa/advertised.sls'),
@@ -440,10 +440,10 @@ def _run(self) -> None:
         root=constants.ISO_IMAGE_ROOT,
         server_root='${}_{}_images'.format(
             config.PROJECT_NAME.lower(),
-            constants.VERSION.replace('.', '_').replace('-', '_')
+            versions.VERSION.replace('.', '_').replace('-', '_')
         ),
         name_prefix='{}-{}/'.format(
-            config.PROJECT_NAME.lower(), constants.VERSION
+            config.PROJECT_NAME.lower(), versions.VERSION
         ),
         destination=Path(
             constants.ISO_ROOT,