graphql: T3993: refactor directive and mutation definitions

(cherry picked from commit ef7f5ca2fd2c0113875dbd9143342e925cf00621)

7 files changed, 44 insertions, 115 deletions

diff --git a/src/services/api/graphql/README.graphql b/src/services/api/graphql/README.graphql
index 6e9e16c6b..29f58f709 100644
--- a/src/services/api/graphql/README.graphql
+++ b/src/services/api/graphql/README.graphql
@@ -101,11 +101,8 @@ services
 │       │       └── schema.graphql
 │       ├── README.graphql
 │       ├── recipes
-│       │   ├── config_file.py
-│       │   ├── create_dhcp_server.py
-│       │   ├── create_interface_ethernet.py
 │       │   ├── __init__.py
-│       │   ├── recipe.py
+│       │   ├── session.py
 │       │   └── templates
 │       │       ├── create_dhcp_server.tmpl
 │       │       └── create_interface_ethernet.tmpl
diff --git a/src/services/api/graphql/graphql/directives.py b/src/services/api/graphql/graphql/directives.py
index a7706610c..f5cd88acd 100644
--- a/src/services/api/graphql/graphql/directives.py
+++ b/src/services/api/graphql/graphql/directives.py
@@ -1,34 +1,37 @@
 from ariadne import SchemaDirectiveVisitor, ObjectType
 from . mutations import make_configure_resolver, make_config_file_resolver
 
-class ConfigureDirective(SchemaDirectiveVisitor):
-    """
-    Class providing implementation of 'configure' directive in schema.
+def non(arg):
+    pass
 
-    """
-    def visit_field_definition(self, field, object_type):
+class VyosDirective(SchemaDirectiveVisitor):
+    def visit_field_definition(self, field, object_type, make_resolver=non):
         name = f'{field.type}'
         # field.type contains the return value of the mutation; trim value
         # to produce canonical name
         name = name.replace('Result', '', 1)
 
-        func = make_configure_resolver(name)
+        func = make_resolver(name)
         field.resolve = func
         return field
 
-class ConfigFileDirective(SchemaDirectiveVisitor):
+
+class ConfigureDirective(VyosDirective):
     """
-    Class providing implementation of 'configfile' directive in schema.
+    Class providing implementation of 'configure' directive in schema.
 
     """
     def visit_field_definition(self, field, object_type):
-        name = f'{field.type}'
-        # field.type contains the return value of the mutation; trim value
-        # to produce canonical name
-        name = name.replace('Result', '', 1)
+        super().visit_field_definition(field, object_type,
+                                       make_resolver=make_configure_resolver)
 
-        func = make_config_file_resolver(name)
-        field.resolve = func
-        return field
+class ConfigFileDirective(VyosDirective):
+    """
+    Class providing implementation of 'configfile' directive in schema.
+
+    """
+    def visit_field_definition(self, field, object_type):
+        super().visit_field_definition(field, object_type,
+                                       make_resolver=make_config_file_resolver)
 
 directives_dict = {"configure": ConfigureDirective, "configfile": ConfigFileDirective}
diff --git a/src/services/api/graphql/graphql/mutations.py b/src/services/api/graphql/graphql/mutations.py
index 02d5be0ef..8a28b13d7 100644
--- a/src/services/api/graphql/graphql/mutations.py
+++ b/src/services/api/graphql/graphql/mutations.py
@@ -6,10 +6,11 @@ from graphql import GraphQLResolveInfo
 from makefun import with_signature
 
 from .. import state
+from api.graphql.recipes.session import Session
 
 mutation = ObjectType("Mutation")
 
-def make_configure_resolver(mutation_name):
+def make_resolver(mutation_name, class_name, session_func):
     """Dynamically generate a resolver for the mutation named in the
     schema by 'mutation_name'.
 
@@ -19,9 +20,9 @@ def make_configure_resolver(mutation_name):
     functools.wraps.
 
     :raise Exception:
-        encapsulating ConfigErrors, or internal errors
+        raising ConfigErrors, or internal errors
     """
-    class_name = mutation_name
+
     func_base_name = convert_camel_case_to_snake(class_name)
     resolver_name = f'resolve_{func_base_name}'
     func_sig = '(obj: Any, info: GraphQLResolveInfo, data: Dict)'
@@ -40,10 +41,17 @@ def make_configure_resolver(mutation_name):
             data = kwargs['data']
             session = state.settings['app'].state.vyos_session
 
-            mod = import_module(f'api.graphql.recipes.{func_base_name}')
-            klass = getattr(mod, class_name)
+            # one may override the session functions with a local subclass
+            try:
+                mod = import_module(f'api.graphql.recipes.{func_base_name}')
+                klass = getattr(mod, class_name)
+            except ImportError:
+                # otherwise, dynamically generate subclass to invoke subclass
+                # name based templates
+                klass = type(class_name, (Session,), {})
             k = klass(session, data)
-            k.configure()
+            method = getattr(k, session_func)
+            method()
 
             return {
                 "success": True,
@@ -57,53 +65,16 @@ def make_configure_resolver(mutation_name):
 
     return func_impl
 
+def make_configure_resolver(mutation_name):
+    class_name = mutation_name
+    return make_resolver(mutation_name, class_name, 'configure')
+
 def make_config_file_resolver(mutation_name):
-    op = ''
     if 'Save' in mutation_name:
-        op = 'save'
+        class_name = mutation_name.replace('Save', '', 1)
+        return make_resolver(mutation_name, class_name, 'save')
     elif 'Load' in mutation_name:
-        op = 'load'
-
-    class_name = mutation_name.replace('Save', '', 1).replace('Load', '', 1)
-    func_base_name = convert_camel_case_to_snake(class_name)
-    resolver_name = f'resolve_{func_base_name}'
-    func_sig = '(obj: Any, info: GraphQLResolveInfo, data: Dict)'
-
-    @mutation.field(mutation_name)
-    @convert_kwargs_to_snake_case
-    @with_signature(func_sig, func_name=resolver_name)
-    async def func_impl(*args, **kwargs):
-        try:
-            if 'data' not in kwargs:
-                return {
-                    "success": False,
-                    "errors": ['missing data']
-                }
-
-            data = kwargs['data']
-            session = state.settings['app'].state.vyos_session
-
-            mod = import_module(f'api.graphql.recipes.{func_base_name}')
-            klass = getattr(mod, class_name)
-            k = klass(session, data)
-            if op == 'save':
-                k.save()
-            elif op == 'load':
-                k.load()
-            else:
-                return {
-                    "success": False,
-                    "errors": ["Input must be saveConfigFile | loadConfigFile"]
-                }
-
-            return {
-                "success": True,
-                "data": data
-            }
-        except Exception as error:
-            return {
-                "success": False,
-                "errors": [str(error)]
-            }
-
-    return func_impl
+        class_name = mutation_name.replace('Load', '', 1)
+        return make_resolver(mutation_name, class_name, 'load')
+    else:
+        raise Exception
diff --git a/src/services/api/graphql/recipes/config_file.py b/src/services/api/graphql/recipes/config_file.py
deleted file mode 100644
index 850e5326e..000000000
--- a/src/services/api/graphql/recipes/config_file.py
+++ /dev/null
@@ -1,16 +0,0 @@
-
-from . recipe import Recipe
-
-class ConfigFile(Recipe):
-    def __init__(self, session, command_file):
-        super().__init__(session, command_file)
-
-    # Define any custom processing of parameters here by overriding
-    # save/load:
-    #
-    # def save(self):
-    #     self.data = transform_data(self.data)
-    #     super().save()
-    # def load(self):
-    #     self.data = transform_data(self.data)
-    #     super().load()
diff --git a/src/services/api/graphql/recipes/create_dhcp_server.py b/src/services/api/graphql/recipes/create_dhcp_server.py
deleted file mode 100644
index ac6f15209..000000000
--- a/src/services/api/graphql/recipes/create_dhcp_server.py
+++ /dev/null
@@ -1,13 +0,0 @@
-
-from . recipe import Recipe
-
-class CreateDhcpServer(Recipe):
-    def __init__(self, session, command_file):
-        super().__init__(session, command_file)
-
-    # Define any custom processing of parameters here by overriding
-    # configure:
-    #
-    # def configure(self):
-    #     self.data = transform_data(self.data)
-    #     super().configure()
diff --git a/src/services/api/graphql/recipes/create_interface_ethernet.py b/src/services/api/graphql/recipes/create_interface_ethernet.py
deleted file mode 100644
index aafb4d55c..000000000
--- a/src/services/api/graphql/recipes/create_interface_ethernet.py
+++ /dev/null
@@ -1,13 +0,0 @@
-
-from . recipe import Recipe
-
-class CreateInterfaceEthernet(Recipe):
-    def __init__(self, session, command_file):
-        super().__init__(session, command_file)
-
-    # Define any custom processing of parameters here by overriding
-    # configure:
-    #
-    # def configure(self):
-    #     self.data = transform_data(self.data)
-    #     super().configure()
diff --git a/src/services/api/graphql/recipes/recipe.py b/src/services/api/graphql/recipes/session.py
index 91d8bd67a..aa3932ab9 100644
--- a/src/services/api/graphql/recipes/recipe.py
+++ b/src/services/api/graphql/recipes/session.py
@@ -2,7 +2,7 @@ from ariadne import convert_camel_case_to_snake
 import vyos.defaults
 from vyos.template import render
 
-class Recipe(object):
+class Session(object):
     def __init__(self, session, data):
         self._session = session
         self.data = data