Relation parameter refactor

README.md

@@ -58,7 +58,7 @@ for more!
 
 Additional resources:
 
-* [Tutorial to build a rock for a Flask application](https://documentation.ubuntu.com/rockcraft/en/latest/tutorial/flask/)
+* [Tutorial to build a rock for a Flask application](https://documentation.ubuntu.com/rockcraft/en/latest/tutorial/flask.html)
 * [Charmcraft `flask-framework` reference](https://juju.is/docs/sdk/charmcraft-extension-flask-framework)
 * [Charmcraft `flask-framework` how to guides](https://juju.is/docs/sdk/build-a-paas-charm)
 * [Rockcraft`flask-framework`

docs/index.rst

@@ -67,7 +67,7 @@ commands that need to be run in the root directory of the Flask application:
    rockcraft pack
 
 The `full Rockcraft tutorial
-<https://documentation.ubuntu.com/rockcraft/en/latest/tutorial/flask/>`_ for
+<https://documentation.ubuntu.com/rockcraft/en/latest/tutorial/flask.html>`_ for
 creating an OCI image for a Flask application takes you from a plain Ubuntu
 installation to a production ready OCI image for your Flask application.
 

examples/fastapi/alembic/versions/eca6177bd16a_initial_migration.py

@@ -4,7 +4,7 @@
 """Initial migration
 
 Revision ID: eca6177bd16a
-Revises: 
+Revises:
 Create Date: 2023-09-05 17:12:56.303534
 
 """

examples/flask/test_db_rock/alembic/versions/eca6177bd16a_initial_migration.py

@@ -4,7 +4,7 @@
 """Initial migration
 
 Revision ID: eca6177bd16a
-Revises: 
+Revises:
 Create Date: 2023-09-05 17:12:56.303534
 
 """

src/paas_charm/charm_state.py

@@ -7,7 +7,7 @@
 import re
 import typing
 from dataclasses import dataclass, field
-from typing import Optional
+from typing import Optional, Type, TypeVar
 
 from charms.data_platform_libs.v0.data_interfaces import DatabaseRequires
 from pydantic import BaseModel, Extra, Field, ValidationError, ValidationInfo, field_validator
@@ -20,20 +20,6 @@
 logger = logging.getLogger(__name__)
 
 
-class ProxyConfig(BaseModel):
-    """Configuration for network access through proxy.
-
-    Attributes:
-        http_proxy: The http proxy URL.
-        https_proxy: The https proxy URL.
-        no_proxy: Comma separated list of hostnames to bypass proxy.
-    """
-
-    http_proxy: str | None = Field(default=None, pattern="https?://.+")
-    https_proxy: str | None = Field(default=None, pattern="https?://.+")
-    no_proxy: typing.Optional[str] = None
-
-
 # too-many-instance-attributes is okay since we use a factory function to construct the CharmState
 class CharmState:  # pylint: disable=too-many-instance-attributes
     """Represents the state of the charm.
@@ -230,8 +216,6 @@ def build(  # pylint: disable=too-many-arguments
     ) -> "IntegrationsState":
         """Initialize a new instance of the IntegrationsState class.
 
-        This functions will raise in the configuration is invalid.
-
         Args:
             redis_uri: The redis uri provided by the redis charm.
             database_requirers: All database requirers object declared by the charm.
@@ -241,35 +225,14 @@ def build(  # pylint: disable=too-many-arguments
 
         Return:
             The IntegrationsState instance created.
-
-        Raises:
-            CharmConfigInvalidError: If some parameter in invalid.
         """
-        if s3_connection_info:
-            try:
-                # s3_connection_info is not really a Dict[str, str] as stated in
-                # charms.data_platform_libs.v0.s3. It is really a
-                # Dict[str, str | list[str]].
-                # Ignoring as mypy does not work correctly with that information.
-                s3_parameters = S3Parameters(**s3_connection_info)  # type: ignore[arg-type]
-            except ValidationError as exc:
-                error_message = build_validation_error_message(exc)
-                raise CharmConfigInvalidError(
-                    f"Invalid S3 configuration: {error_message}"
-                ) from exc
-        else:
-            s3_parameters = None
-
-        if saml_relation_data is not None:
-            try:
-                saml_parameters = SamlParameters(**saml_relation_data)
-            except ValidationError as exc:
-                error_message = build_validation_error_message(exc)
-                raise CharmConfigInvalidError(
-                    f"Invalid Saml configuration: {error_message}"
-                ) from exc
-        else:
-            saml_parameters = None
+        s3_parameters = typing.cast(
+            S3Parameters | None, generate_relation_parameters(s3_connection_info, S3Parameters)
+        )
+        saml_parameters = typing.cast(
+            SamlParameters | None,
+            generate_relation_parameters(saml_relation_data, SamlParameters, True),
+        )
 
         # Workaround as the Redis library temporarily sends the port
         # as None while the integration is being created.
@@ -289,6 +252,55 @@ def build(  # pylint: disable=too-many-arguments
         )
 
 
+RelationParam = TypeVar("RelationParam", "SamlParameters", "S3Parameters")
+
+
+def generate_relation_parameters(
+    relation_data: dict[str, str] | typing.MutableMapping[str, str] | None,
+    parameter_type: Type[RelationParam],
+    support_empty: bool = False,
+) -> "RelationParam | None":
+    """Generate relation parameter class from relation data.
+
+    Args:
+        relation_data: Relation data.
+        parameter_type: Parameter type to use.
+        support_empty: Support empty relation data.
+
+    Return:
+        Parameter instance created.
+
+    Raises:
+        CharmConfigInvalidError: If some parameter in invalid.
+    """
+    if not support_empty and not relation_data:
+        return None
+    if relation_data is None:
+        return None
+
+    try:
+        return parameter_type.parse_obj(relation_data)
+    except ValidationError as exc:
+        error_message = build_validation_error_message(exc)
+        raise CharmConfigInvalidError(
+            f"Invalid {parameter_type.__name__} configuration: {error_message}"
+        ) from exc
+
+
+class ProxyConfig(BaseModel):
+    """Configuration for network access through proxy.
+
+    Attributes:
+        http_proxy: The http proxy URL.
+        https_proxy: The https proxy URL.
+        no_proxy: Comma separated list of hostnames to bypass proxy.
+    """
+
+    http_proxy: str | None = Field(default=None, pattern="https?://.+")
+    https_proxy: str | None = Field(default=None, pattern="https?://.+")
+    no_proxy: typing.Optional[str] = None
+
+
 class S3Parameters(BaseModel):
     """Configuration for accessing S3 bucket.
 

src/paas_charm/charm_utils.py

@@ -33,7 +33,7 @@ def update_app_and_unit_status(self, status: ops.StatusBase) -> None:
 
 
 def block_if_invalid_config(
-    method: typing.Callable[[C, E], None]
+    method: typing.Callable[[C, E], None],
 ) -> typing.Callable[[C, E], None]:
     """Create a decorator that puts the charm in blocked state if the config is wrong.