feature(schema): add networkv2 schema

Adds networkv2 schema definition file, removes skipping of schema
validation for networkv2, and adds unit tests for same.

cloudinit/config/schema.py

@@ -66,6 +66,7 @@
 # 3. Add the new version definition to versions.schema.cloud-config.json
 USERDATA_SCHEMA_FILE = "schema-cloud-config-v1.json"
 NETWORK_CONFIG_V1_SCHEMA_FILE = "schema-network-config-v1.json"
+NETWORK_CONFIG_V2_SCHEMA_FILE = "schema-network-config-v2.json"
 
 _YAML_MAP = {True: "true", False: "false", None: "null"}
 SCHEMA_DOC_TMPL = """
@@ -169,7 +170,9 @@ class SchemaType(Enum):
         "latest": USERDATA_SCHEMA_FILE,
     },
     SchemaType.NETWORK_CONFIG: {
-        "latest": NETWORK_CONFIG_V1_SCHEMA_FILE,
+        "latest": NETWORK_CONFIG_V2_SCHEMA_FILE,
+        "1": NETWORK_CONFIG_V1_SCHEMA_FILE,
+        "2": NETWORK_CONFIG_V2_SCHEMA_FILE,
     },
 }
 
@@ -717,15 +720,15 @@ def validate_cloudconfig_schema(
         NETWORK_CONFIG
     """
     if schema_type == SchemaType.NETWORK_CONFIG:
-        if network_schema_version(config) == 2:
+        network_version = network_schema_version(config)
+        if network_version == 2:
             if netplan_validate_network_schema(
                 network_config=config, strict=strict, log_details=log_details
             ):
                 # Schema was validated by netplan
                 return True
-            # network-config schema version 2 but no netplan.
-            # TODO(add JSON schema definition for network version 2)
-            return False
+        if network_version is not None:
+            schema = get_schema(schema_type, str(network_version))
 
     if schema is None:
         schema = get_schema(schema_type)
@@ -1125,18 +1128,13 @@ def validate_cloudconfig_file(
                 network_config=cloudconfig, strict=True, annotate=annotate
             ):
                 return True  # schema validation performed by netplan
-        if network_version != 1:
-            # Validation requires JSON schema definition in
-            # cloudinit/config/schemas/schema-network-config-v1.json
-            print(
-                "Skipping network-config schema validation."
-                " No network schema for version:"
-                f" {network_schema_version(cloudconfig)}"
-            )
-            return False
     try:
         if not validate_cloudconfig_schema(
-            cloudconfig, schema=schema, strict=True, log_deprecations=False
+            cloudconfig,
+            schema=schema,
+            schema_type=schema_type,
+            strict=True,
+            log_deprecations=False,
         ):
             print(
                 f"Skipping {schema_type.value} schema validation."
@@ -1557,13 +1555,16 @@ def get_schema_dir() -> str:
     return os.path.join(os.path.dirname(os.path.abspath(__file__)), "schemas")
 
 
-def get_schema(schema_type: SchemaType = SchemaType.CLOUD_CONFIG) -> dict:
+def get_schema(
+    schema_type: SchemaType = SchemaType.CLOUD_CONFIG,
+    version: str = "latest",
+) -> dict:
     """Return jsonschema for a specific type.
 
     Return empty schema when no specific schema file exists.
     """
     schema_file = os.path.join(
-        get_schema_dir(), SCHEMA_FILES_BY_TYPE[schema_type]["latest"]
+        get_schema_dir(), SCHEMA_FILES_BY_TYPE[schema_type][version]
     )
     full_schema = None
     try: