chore(interfaces): move data-nosql schemas to new format

interfaces/etcd_client/interface/v0/schema.py

@@ -1,12 +1,27 @@
 # Copyright 2025 Canonical
 # See LICENSE file for licensing details.
 
-from interface_tester.schema_base import DataBagSchema
-from pydantic import Field
+from pydantic import BaseModel, ConfigDict, Field
 
 
-class ProviderSchema(DataBagSchema):
-    """The schema for the provider side of this interface."""
+class _BareStringDatabag(BaseModel):
+    """Base class for databag models that don't strictly JSON encode all entries."""
+
+    @staticmethod
+    def __juju_decoder__(value: str) -> str:
+        """Pass Juju's string through unmodified to be decoded by individual field validators."""
+        return value
+
+    @staticmethod
+    def __juju_encoder__(value: str | None) -> str:
+        """Convert `None` to "", erasing the value; Ops will error on a non-string."""
+        return "" if value is None else value
+
+
+class ProviderAppData(_BareStringDatabag):
+    """The provider's application databag."""
+
+    model_config = ConfigDict(strict=True, populate_by_name=True)
 
     endpoints: str = Field(
         description="Comma separated list of etcd endpoints",
@@ -21,20 +36,24 @@ class ProviderSchema(DataBagSchema):
     )
 
     secret_tls: str = Field(
+        alias="secret-tls",
         description="Secret URI containing the tls-ca",
         title="TLS Secret URI",
         examples=["secret://12312323112313123213"],
     )
 
     secret_user: str = Field(
+        alias="secret-user",
         description="Secret URI containing the etcd user information",
         title="User Secret URI",
         examples=["secret://12312323112313123213"],
     )
 
 
-class RequirerSchema(DataBagSchema):
-    """The schema for the requirer side of this interface."""
+class RequirerAppData(_BareStringDatabag):
+    """The requirer's application databag."""
+
+    model_config = ConfigDict(strict=True, populate_by_name=True)
 
     prefix: str = Field(
         description="The prefix of the range of keys requested",
@@ -43,19 +62,26 @@ class RequirerSchema(DataBagSchema):
     )
 
     secret_mtls: str = Field(
+        alias="secret-mtls",
         description="Secret URI containing the client certificate",
         title="mTLS Secret URI",
         examples=["secret://12312323112313123213"],
     )
 
     requested_secrets: str = Field(
-        description="The fields required to be a secret.",
+        alias="requested-secrets",
+        description="The fields required to be a secret. A JSON array on the wire.",
         title="Requested Secrets",
         examples='["username", "uris", "tls", "tls-ca"]',
     )
 
     provided_secrets: str = Field(
-        description="The fields provided as secrets",
+        alias="provided-secrets",
+        description="The fields provided as secrets. A JSON array on the wire.",
         title="Provided Secrets",
         examples='["mtls-cert"]',
     )
+
+
+ProviderUnitData = None
+RequirerUnitData = None

interfaces/etcd_client/ruff.toml

@@ -9,10 +9,3 @@ quote-style = "preserve"
     "D",  # docs
     "E501",  # line too long
 ]
-"./interface/v*/tests/*.py" = [
-    "CPY",  # copyright
-    "D",  # docs
-    "S",  # security
-    "E501",  # line too long
-    "F841",  # assignment to unused variable
-]

interfaces/mongodb_client/interface/v0/schema.py

@@ -1,17 +1,30 @@
-"""This file defines the schemas for the provider and requirer sides of the mongodb_client interface.
+"""This file defines the schemas for the provider and requirer sides of the mongodb_client interface."""
 
-It must expose two interfaces.schema_base.DataBagSchema subclasses called:
-- ProviderSchema
-- RequirerSchema
-"""
+import json
+from typing import Any
 
-from interface_tester.schema_base import DataBagSchema
-from pydantic import BaseModel, Field
+from pydantic import BaseModel, ConfigDict, Field, field_serializer, field_validator
 
 
-class MongoDBProviderData(BaseModel):
+class _BareStringDatabag(BaseModel):
+    """Base class for databag models that don't strictly JSON encode all entries."""
+
+    @staticmethod
+    def __juju_decoder__(value: str) -> str:
+        """Pass Juju's string through unmodified to be decoded by individual field validators."""
+        return value
+
+    @staticmethod
+    def __juju_encoder__(value: str | None) -> str:
+        """Convert `None` to "", erasing the value; Ops will error on a non-string."""
+        return "" if value is None else value
+
+
+class ProviderAppData(_BareStringDatabag):
     """The databag for the provider side of this interface."""
 
+    model_config = ConfigDict(strict=True, populate_by_name=True)
+
     database: str = Field(
         description="The database name delivered by the provider. Might not be the same as requested by the requirer",
         examples=["myapp"],
@@ -74,9 +87,11 @@ class MongoDBProviderData(BaseModel):
     )
 
 
-class MongoDBRequirerData(BaseModel):
+class RequirerAppData(_BareStringDatabag):
     """The databag for the requirer side of this interface."""
 
+    model_config = ConfigDict(strict=True, populate_by_name=True)
+
     database: str = Field(
         description="The database name requested by the requirer",
         examples=["myapp"],
@@ -85,7 +100,7 @@ class MongoDBRequirerData(BaseModel):
 
     requested_secrets: list[str] = Field(
         alias="requested-secrets",
-        description="Any provider field which should be transferred as Juju Secret",
+        description="Any provider field which should be transferred as Juju Secret. A JSON array on the wire.",
         examples=[["username", "password"]],
         title="Requested secrets",
     )
@@ -124,14 +139,17 @@ class MongoDBRequirerData(BaseModel):
         title="Entity permissions",
     )
 
+    @field_validator("requested_secrets", mode="before")
+    @classmethod
+    def _load_json(cls, value: Any) -> Any:
+        if not isinstance(value, str):
+            return value  # __init__ argument was already deserialized.
+        return json.loads(value)
 
-class ProviderSchema(DataBagSchema):
-    """The schema for the provider side of this interface."""
-
-    app: MongoDBProviderData
-
+    @field_serializer("requested_secrets")
+    def _dump_json(self, value: object) -> str:
+        return json.dumps(value)
 
-class RequirerSchema(DataBagSchema):
-    """The schema for the requirer side of this interface."""
 
-    app: MongoDBRequirerData
+ProviderUnitData = None
+RequirerUnitData = None

interfaces/opensearch_client/interface/v0/schema.py

@@ -1,17 +1,30 @@
-"""This file defines the schemas for the provider and requirer sides of the opensearch_client interface.
+"""This file defines the schemas for the provider and requirer sides of the opensearch_client interface."""
 
-It must expose two interfaces.schema_base.DataBagSchema subclasses called:
-- ProviderSchema
-- RequirerSchema
-"""
+import json
+from typing import Any
 
-from interface_tester.schema_base import DataBagSchema
-from pydantic import BaseModel, Field
+from pydantic import BaseModel, ConfigDict, Field, field_serializer, field_validator
 
 
-class OpenSearchProviderData(BaseModel):
+class _BareStringDatabag(BaseModel):
+    """Base class for databag models that don't strictly JSON encode all entries."""
+
+    @staticmethod
+    def __juju_decoder__(value: str) -> str:
+        """Pass Juju's string through unmodified to be decoded by individual field validators."""
+        return value
+
+    @staticmethod
+    def __juju_encoder__(value: str | None) -> str:
+        """Convert `None` to "", erasing the value; Ops will error on a non-string."""
+        return "" if value is None else value
+
+
+class ProviderAppData(_BareStringDatabag):
     """The databag for the provider side of this interface."""
 
+    model_config = ConfigDict(strict=True, populate_by_name=True)
+
     index: str = Field(
         description="The index that has been made available to the relation user. Name defined in the Requirer's index field",
         examples=["myindex"],
@@ -60,9 +73,11 @@ class OpenSearchProviderData(BaseModel):
     )
 
 
-class OpenSearchRequirerData(BaseModel):
+class RequirerAppData(_BareStringDatabag):
     """The databag for the requirer side of this interface."""
 
+    model_config = ConfigDict(strict=True, populate_by_name=True)
+
     index: str = Field(
         description="The index name requested by the requirer",
         examples=["myindex"],
@@ -71,7 +86,7 @@ class OpenSearchRequirerData(BaseModel):
 
     requested_secrets: list[str] = Field(
         alias="requested-secrets",
-        description="Any provider field which should be transferred as Juju Secret",
+        description="Any provider field which should be transferred as Juju Secret. A JSON array on the wire.",
         examples=[["username", "password"]],
         title="Requested secrets",
     )
@@ -110,14 +125,17 @@ class OpenSearchRequirerData(BaseModel):
         title="Entity permissions",
     )
 
+    @field_validator("requested_secrets", mode="before")
+    @classmethod
+    def _load_json(cls, value: Any) -> Any:
+        if not isinstance(value, str):
+            return value  # __init__ argument was already deserialized.
+        return json.loads(value)
 
-class ProviderSchema(DataBagSchema):
-    """The schema for the provider side of this interface."""
-
-    app: OpenSearchProviderData
-
+    @field_serializer("requested_secrets")
+    def _dump_json(self, value: object) -> str:
+        return json.dumps(value)
 
-class RequirerSchema(DataBagSchema):
-    """The schema for the requirer side of this interface."""
 
-    app: OpenSearchRequirerData
+ProviderUnitData = None
+RequirerUnitData = None