json-builder-compat

resolvers/reader.py

@@ -7,7 +7,7 @@ from orm.author import Author
 from orm.reaction import Reaction, ReactionKind
 from orm.shout import Shout, ShoutAuthor, ShoutTopic
 from orm.topic import Topic
-from services.db import local_session
+from services.db import local_session, json_builder, json_array_builder
 from services.schema import query
 from services.search import search_text
 from services.viewed import ViewedStorage
@@ -71,7 +71,7 @@ def query_with_stat(info):
     # main_author
     q = q.join(main_author, main_author.id == Shout.created_by)
     q = q.add_columns(
-        func.json_object(
+        json_builder(
             'id', main_author.id,
             'name', main_author.name,
             'slug', main_author.slug,
@@ -92,7 +92,7 @@ def query_with_stat(info):
             main_topic.id == main_topic_join.topic
         )
         q = q.add_columns(
-            func.json_object(
+            json_builder(
                 'id', main_topic.id,
                 'title', main_topic.title,
                 'slug', main_topic.slug,
@@ -103,8 +103,8 @@ def query_with_stat(info):
     if has_field(info, "topics"):
         topics_subquery = (
             select(
-                func.json_group_array(
+                json_array_builder(
-                    func.json_object(
+                    json_builder(
                         'id', Topic.id,
                         'title', Topic.title,
                         'slug', Topic.slug,
@@ -122,8 +122,8 @@ def query_with_stat(info):
     if has_field(info, "authors"):
         authors_subquery = (
             select(
-                func.json_group_array(
+                json_array_builder(
-                    func.json_object(
+                    json_builder(
                         'id', Author.id,
                         'name', Author.name,
                         'slug', Author.slug,
@@ -175,7 +175,7 @@ def query_with_stat(info):
         q = q.outerjoin(stats_subquery, stats_subquery.c.shout == Shout.id)
         # aggregate in one column
         q = q.add_columns(
-            func.json_object(
+            json_builder(
                 'comments_count', stats_subquery.c.comments_count,
                 'rating', stats_subquery.c.rating,
                 'last_reacted_at', stats_subquery.c.last_reacted_at,

services/db.py

@@ -5,7 +5,7 @@ import traceback
 import warnings
 from typing import Any, Callable, Dict, TypeVar
 
-from sqlalchemy import JSON, Column, Engine, Integer, create_engine, event, exc, inspect
+from sqlalchemy import JSON, Column, Engine, Integer, create_engine, event, exc, func, inspect
 from sqlalchemy.ext.declarative import declarative_base
 from sqlalchemy.orm import Session, configure_mappers
 from sqlalchemy.sql.schema import Table
@@ -148,3 +148,19 @@ def after_cursor_execute(conn, cursor, statement, parameters, context, executema
                 logger.debug("*" * (elapsed_n))
                 logger.debug(f"{elapsed:.3f} s")
         del conn.cursor_id  # Удаление идентификатора курсора после выполнения
+
+
+def get_json_builder():
+    """
+    Возвращает подходящие функции для построения JSON объектов в зависимости от драйвера БД
+    """
+    dialect = engine.dialect.name
+    if dialect.startswith('postgres'):
+        return func.json_build_object, func.json_agg
+    elif dialect.startswith('sqlite') or dialect.startswith('mysql'):
+        return func.json_object, func.json_group_array
+    else:
+        raise NotImplementedError(f"JSON builder not implemented for dialect {dialect}")
+
+# Используем их в коде
+json_builder, json_array_builder = get_json_builder()