add json export format (#829)

docs/configurations.md

@@ -233,7 +233,7 @@ The export options can be set per model and includes the following options:
 * `column_export_list`: List of columns to include in the export data. Default is all model columns.
 * `column_export_exclude_list`: List of columns to exclude in the export data.
 * `export_max_rows`: Maximum number of rows to be exported. Default value is `0` which means unlimited.
-* `export_types`: List of export types to be enabled. Default value is `["csv"]`.
+* `export_types`: List of export types to be enabled. Default value is `["csv","json"]`.
 
 ## Templates
 

sqladmin/models.py

@@ -1,5 +1,6 @@
 from __future__ import annotations
 
+import json
 import time
 import warnings
 from enum import Enum
@@ -454,7 +455,7 @@ class UserAdmin(ModelView, model=User):
         ```
     """
 
-    export_types: ClassVar[List[str]] = ["csv"]
+    export_types: ClassVar[List[str]] = ["csv", "json"]
     """A list of available export filetypes.
     Currently only `csv` is supported.
     """
@@ -1158,7 +1159,9 @@ async def export_data(
     ) -> StreamingResponse:
         if export_type == "csv":
             return await self._export_csv(data)
-        raise NotImplementedError("Only export_type='csv' is implemented.")
+        elif export_type == "json":
+            return await self._export_json(data)
+        raise NotImplementedError("Only export_type='csv' or 'json' is implemented.")
 
     async def _export_csv(
         self,
@@ -1185,6 +1188,30 @@ async def generate(writer: Writer) -> AsyncGenerator[Any, None]:
             headers={"Content-Disposition": f"attachment;filename={filename}"},
         )
 
+    async def _export_json(
+        self,
+        data: List[Any],
+    ) -> StreamingResponse:
+        async def generate() -> AsyncGenerator[str, None]:
+            yield "["
+            separator = "," if len(data) > 1 else ""
+
+            for row in data:
+                row_dict = {
+                    name: await self.get_prop_value(row, name)
+                    for name in self._export_prop_names
+                }
+                yield json.dumps(row_dict) + separator
+
+            yield "]"
+
+        filename = secure_filename(self.get_export_name(export_type="json"))
+        return StreamingResponse(
+            content=generate(),
+            media_type="application/json",
+            headers={"Content-Disposition": f"attachment;filename={filename}"},
+        )
+
     def _refresh_form_rules_cache(self) -> None:
         if self.form_rules:
             self._form_create_rules = self.form_rules

tests/test_views/test_view_async.py

@@ -778,11 +778,26 @@ def row_count(resp) -> int:
     assert row_count(response) == 3
 
 
+async def test_export_json(client: AsyncClient) -> None:
+    async with session_maker() as session:
+        user = User(name="Daniel", status="ACTIVE")
+        session.add(user)
+        await session.commit()
+
+    response = await client.get("/admin/user/export/json")
+    assert response.text == '[{"name": "Daniel", "status": "ACTIVE"}]'
+
+
 async def test_export_bad_type_is_404(client: AsyncClient) -> None:
     response = await client.get("/admin/user/export/bad_type")
     assert response.status_code == 404
 
 
-async def test_export_permission(client: AsyncClient) -> None:
+async def test_export_permission_csv(client: AsyncClient) -> None:
     response = await client.get("/admin/movie/export/csv")
     assert response.status_code == 403
+
+
+async def test_export_permission_json(client: AsyncClient) -> None:
+    response = await client.get("/admin/movie/export/json")
+    assert response.status_code == 403

tests/test_views/test_view_sync.py

@@ -731,6 +731,16 @@ def test_export_csv(client: TestClient) -> None:
     assert response.text == "name,status\r\nDaniel,ACTIVE\r\n"
 
 
+def test_export_json(client: TestClient) -> None:
+    with session_maker() as session:
+        user = User(name="Daniel", status="ACTIVE")
+        session.add(user)
+        session.commit()
+
+    response = client.get("/admin/user/export/json")
+    assert response.text == '[{"name": "Daniel", "status": "ACTIVE"}]'
+
+
 def test_export_csv_row_count(client: TestClient) -> None:
     def row_count(resp) -> int:
         return resp.text.count("\r\n") - 1