graphql: T4544: add script to generate GraphQL schema for op-mode

2 files changed, 202 insertions, 0 deletions

diff --git a/src/services/api/graphql/utils/schema_from_op_mode.py b/src/services/api/graphql/utils/schema_from_op_mode.py
new file mode 100755
index 000000000..cdde5f187
--- /dev/null
+++ b/src/services/api/graphql/utils/schema_from_op_mode.py
@@ -0,0 +1,161 @@
+#!/usr/bin/env python3
+#
+# Copyright (C) 2022 VyOS maintainers and contributors
+#
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License version 2 or later as
+# published by the Free Software Foundation.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+#
+#
+# A utility to generate GraphQL schema defintions from standardized op-mode
+# scripts.
+
+import os
+import json
+import typing
+from inspect import signature, getmembers, isfunction
+from jinja2 import Template
+
+from vyos.defaults import directories
+from . util import load_as_module, is_op_mode_function_name, is_show_function_name
+
+OP_MODE_PATH = directories['op_mode']
+SCHEMA_PATH = directories['api_schema']
+DATA_DIR = directories['data']
+
+op_mode_include_file = os.path.join(DATA_DIR, 'op-mode-standardized.json')
+
+schema_data: dict = {'schema_name': '',
+                     'schema_fields': []}
+
+query_template  = """
+input {{ schema_name }}Input {
+    key: String!
+    {%- for field_entry in schema_fields %}
+    {{ field_entry }}
+    {%- endfor %}
+}
+
+type {{ schema_name }} {
+    result: Generic
+}
+
+type {{ schema_name }}Result {
+    data: {{ schema_name }}
+    success: Boolean!
+    errors: [String]
+}
+
+extend type Query {
+    {{ schema_name }}(data: {{ schema_name }}Input) : {{ schema_name }}Result @genopquery
+}
+"""
+
+mutation_template  = """
+input {{ schema_name }}Input {
+    key: String!
+    {%- for field_entry in schema_fields %}
+    {{ field_entry }}
+    {%- endfor %}
+}
+
+type {{ schema_name }} {
+    result: Generic
+}
+
+type {{ schema_name }}Result {
+    data: {{ schema_name }}
+    success: Boolean!
+    errors: [String]
+}
+
+extend type Mutation {
+    {{ schema_name }}(data: {{ schema_name }}Input) : {{ schema_name }}Result @genopmutation
+}
+"""
+
+def _snake_to_pascal_case(name: str) -> str:
+    res = ''.join(map(str.title, name.split('_')))
+    return res
+
+def _map_type_name(type_name: type, optional: bool = False) -> str:
+    if type_name == str:
+        return 'String!' if not optional else 'String = null'
+    if type_name == int:
+        return 'Int!' if not optional else 'Int = null'
+    if type_name == bool:
+        return 'Boolean!' if not optional else 'Boolean = false'
+    if typing.get_origin(type_name) == list:
+        if not optional:
+            return f'[{_map_type_name(typing.get_args(type_name)[0])}]!'
+        return f'[{_map_type_name(typing.get_args(type_name)[0])}]'
+    # typing.Optional is typing.Union[_, NoneType]
+    if (typing.get_origin(type_name) is typing.Union and
+            typing.get_args(type_name)[1] == type(None)):
+        return f'{_map_type_name(typing.get_args(type_name)[0], optional=True)}'
+
+    # scalar 'Generic' is defined in schema.graphql
+    return 'Generic'
+
+def create_schema(func_name: str, base_name: str, func: callable) -> str:
+    sig = signature(func)
+
+    field_dict = {}
+    for k in sig.parameters:
+        field_dict[sig.parameters[k].name] = _map_type_name(sig.parameters[k].annotation)
+
+    # It is assumed that if one is generating a schema for a 'show_*'
+    # function, that 'get_raw_data' is present and 'raw' is desired.
+    if 'raw' in list(field_dict):
+        del field_dict['raw']
+
+    schema_fields = []
+    for k,v in field_dict.items():
+        schema_fields.append(k+': '+v)
+
+    schema_data['schema_name'] = _snake_to_pascal_case(func_name + '_' + base_name)
+    schema_data['schema_fields'] = schema_fields
+
+    if is_show_function_name(func_name):
+        j2_template = Template(query_template)
+    else:
+        j2_template = Template(mutation_template)
+
+    res = j2_template.render(schema_data)
+
+    return res
+
+def generate_op_mode_definitions():
+    with open(op_mode_include_file) as f:
+        op_mode_files = json.load(f)
+
+    for file in op_mode_files:
+        basename = os.path.splitext(file)[0]
+        module = load_as_module(basename, os.path.join(OP_MODE_PATH, file))
+
+        funcs = getmembers(module, isfunction)
+        funcs = list(filter(lambda ft: is_op_mode_function_name(ft[0]), funcs))
+
+        funcs_dict = {}
+        for (name, thunk) in funcs:
+            funcs_dict[name] = thunk
+
+        results = []
+        for name,func in funcs_dict.items():
+            res = create_schema(name, basename, func)
+            results.append(res)
+
+        out = '\n'.join(results)
+        with open(f'{SCHEMA_PATH}/{basename}.graphql', 'w') as f:
+            f.write(out)
+
+if __name__ == '__main__':
+    generate_op_mode_definitions()
diff --git a/src/services/api/graphql/utils/util.py b/src/services/api/graphql/utils/util.py
new file mode 100644
index 000000000..bf30f673a
--- /dev/null
+++ b/src/services/api/graphql/utils/util.py
@@ -0,0 +1,41 @@
+# Copyright 2022 VyOS maintainers and contributors <maintainers@vyos.io>
+#
+# This library is free software; you can redistribute it and/or
+# modify it under the terms of the GNU Lesser General Public
+# License as published by the Free Software Foundation; either
+# version 2.1 of the License, or (at your option) any later version.
+#
+# This library is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+# Lesser General Public License for more details.
+#
+# You should have received a copy of the GNU Lesser General Public License
+# along with this library.  If not, see <http://www.gnu.org/licenses/>.
+
+import os
+import re
+import importlib.util
+
+from vyos.defaults import directories
+
+def load_as_module(name: str, path: str):
+    spec = importlib.util.spec_from_file_location(name, path)
+    mod = importlib.util.module_from_spec(spec)
+    spec.loader.exec_module(mod)
+    return mod
+
+def load_op_mode_as_module(name: str):
+    path = os.path.join(directories['op_mode'], name)
+    name = os.path.splitext(name)[0]
+    return load_as_module(name, path)
+
+def is_op_mode_function_name(name):
+    if re.match(r"^(show|clear|reset|restart)", name):
+        return True
+    return False
+
+def is_show_function_name(name):
+    if re.match(r"^show", name):
+        return True
+    return False