feat: file edit added

webui/backend/app/api/routes_files.py

@@ -2,7 +2,7 @@ from __future__ import annotations
 
 from fastapi import APIRouter, Depends
 
-from backend.app.api.schemas import DeleteRequest, DeleteResponse, MkdirRequest, MkdirResponse, RenameRequest, RenameResponse, ViewResponse
+from backend.app.api.schemas import DeleteRequest, DeleteResponse, MkdirRequest, MkdirResponse, RenameRequest, RenameResponse, SaveRequest, SaveResponse, ViewResponse
 from backend.app.dependencies import get_file_ops_service
 from backend.app.services.file_ops_service import FileOpsService
 
@@ -36,6 +36,19 @@ async def delete(
 @router.get("/view", response_model=ViewResponse)
 async def view(
     path: str,
+    for_edit: bool = False,
     service: FileOpsService = Depends(get_file_ops_service),
 ) -> ViewResponse:
-    return service.view(path=path)
+    return service.view(path=path, for_edit=for_edit)
+
+
+@router.post("/save", response_model=SaveResponse)
+async def save(
+    request: SaveRequest,
+    service: FileOpsService = Depends(get_file_ops_service),
+) -> SaveResponse:
+    return service.save(
+        path=request.path,
+        content=request.content,
+        expected_modified=request.expected_modified,
+    )

webui/backend/app/api/schemas.py

@@ -65,9 +65,22 @@ class ViewResponse(BaseModel):
     encoding: str
     truncated: bool
     size: int
+    modified: str
     content: str
 
 
+class SaveRequest(BaseModel):
+    path: str
+    content: str
+    expected_modified: str
+
+
+class SaveResponse(BaseModel):
+    path: str
+    size: int
+    modified: str
+
+
 class TaskListItem(BaseModel):
     id: str
     operation: str

webui/backend/app/fs/filesystem_adapter.py

@@ -65,11 +65,25 @@ class FilesystemAdapter:
         limit = max_bytes + 1
         with path.open("rb") as in_f:
             raw = in_f.read(limit)
+        modified = self.modified_iso(path)
         truncated = size > max_bytes or len(raw) > max_bytes
         if truncated:
             raw = raw[:max_bytes]
         return {
             "size": size,
+            "modified": modified,
             "truncated": truncated,
             "content": raw.decode(encoding, errors="replace"),
         }
+
+    def write_text_file(self, path: Path, content: str, encoding: str = "utf-8") -> dict:
+        path.write_text(content, encoding=encoding)
+        return {
+            "size": int(path.stat().st_size),
+            "modified": self.modified_iso(path),
+        }
+
+    @staticmethod
+    def modified_iso(path: Path) -> str:
+        stat = path.stat()
+        return datetime.fromtimestamp(stat.st_mtime, tz=timezone.utc).isoformat().replace("+00:00", "Z")

webui/backend/app/services/file_ops_service.py

@@ -3,11 +3,12 @@ from __future__ import annotations
 from pathlib import Path
 
 from backend.app.api.errors import AppError
-from backend.app.api.schemas import DeleteResponse, MkdirResponse, RenameResponse, ViewResponse
+from backend.app.api.schemas import DeleteResponse, MkdirResponse, RenameResponse, SaveResponse, ViewResponse
 from backend.app.fs.filesystem_adapter import FilesystemAdapter
 from backend.app.security.path_guard import PathGuard
 
 TEXT_PREVIEW_MAX_BYTES = 256 * 1024
+TEXT_EDIT_MAX_BYTES = 256 * 1024
 TEXT_CONTENT_TYPES = {
     ".txt": "text/plain",
     ".log": "text/plain",
@@ -146,7 +147,7 @@ class FileOpsService:
 
         return DeleteResponse(path=resolved_target.relative)
 
-    def view(self, path: str) -> ViewResponse:
+    def view(self, path: str, for_edit: bool = False) -> ViewResponse:
         resolved_target = self._path_guard.resolve_existing_path(path)
 
         if resolved_target.absolute.is_dir():
@@ -173,6 +174,14 @@ class FileOpsService:
                 details={"path": resolved_target.relative},
             )
 
+        if for_edit and resolved_target.absolute.stat().st_size > TEXT_EDIT_MAX_BYTES:
+            raise AppError(
+                code="file_too_large",
+                message="File is too large for edit",
+                status_code=409,
+                details={"path": resolved_target.relative},
+            )
+
         try:
             preview = self._filesystem.read_text_preview(
                 resolved_target.absolute,
@@ -194,9 +203,71 @@ class FileOpsService:
             encoding="utf-8",
             truncated=preview["truncated"],
             size=preview["size"],
+            modified=preview["modified"],
             content=preview["content"],
         )
 
+    def save(self, path: str, content: str, expected_modified: str) -> SaveResponse:
+        resolved_target = self._path_guard.resolve_existing_path(path)
+
+        if resolved_target.absolute.is_dir():
+            raise AppError(
+                code="type_conflict",
+                message="Source must be a file",
+                status_code=409,
+                details={"path": resolved_target.relative},
+            )
+        if not resolved_target.absolute.is_file():
+            raise AppError(
+                code="type_conflict",
+                message="Unsupported path type for save",
+                status_code=409,
+                details={"path": resolved_target.relative},
+            )
+        if self._content_type_for(resolved_target.absolute) is None:
+            raise AppError(
+                code="unsupported_type",
+                message="File type is not supported for edit",
+                status_code=409,
+                details={"path": resolved_target.relative},
+            )
+        if len(content.encode("utf-8")) > TEXT_EDIT_MAX_BYTES:
+            raise AppError(
+                code="file_too_large",
+                message="File is too large for edit",
+                status_code=409,
+                details={"path": resolved_target.relative},
+            )
+
+        current_modified = self._filesystem.modified_iso(resolved_target.absolute)
+        if current_modified != expected_modified:
+            raise AppError(
+                code="conflict",
+                message="File changed since it was opened",
+                status_code=409,
+                details={"path": resolved_target.relative},
+            )
+
+        try:
+            saved = self._filesystem.write_text_file(
+                resolved_target.absolute,
+                content=content,
+                encoding="utf-8",
+            )
+        except OSError as exc:
+            raise AppError(
+                code="io_error",
+                message="Filesystem operation failed",
+                status_code=500,
+                details={"reason": str(exc)},
+            )
+
+        return SaveResponse(
+            path=resolved_target.relative,
+            size=saved["size"],
+            modified=saved["modified"],
+        )
+
     @staticmethod
     def _join_relative(base: str, name: str) -> str:
         return f"{base}/{name}" if base else name

webui/backend/tests/golden/test_api_edit_golden.py

@@ -0,0 +1,168 @@
+from __future__ import annotations
+
+import asyncio
+import sys
+import tempfile
+import time
+import unittest
+from pathlib import Path
+
+import httpx
+
+sys.path.insert(0, str(Path(__file__).resolve().parents[3]))
+
+from backend.app.dependencies import get_file_ops_service
+from backend.app.fs.filesystem_adapter import FilesystemAdapter
+from backend.app.main import app
+from backend.app.security.path_guard import PathGuard
+from backend.app.services.file_ops_service import FileOpsService
+
+
+class FailingWriteFilesystemAdapter(FilesystemAdapter):
+    def write_text_file(self, path: Path, content: str, encoding: str = "utf-8") -> dict:
+        raise OSError("forced write failure")
+
+
+class EditApiGoldenTest(unittest.TestCase):
+    def setUp(self) -> None:
+        self.temp_dir = tempfile.TemporaryDirectory()
+        self.root = Path(self.temp_dir.name) / "root"
+        self.root.mkdir(parents=True, exist_ok=True)
+        self.path_guard = PathGuard({"storage1": str(self.root)})
+        self._set_service(FilesystemAdapter())
+
+    def tearDown(self) -> None:
+        app.dependency_overrides.clear()
+        self.temp_dir.cleanup()
+
+    def _set_service(self, filesystem: FilesystemAdapter) -> None:
+        service = FileOpsService(path_guard=self.path_guard, filesystem=filesystem)
+
+        async def _override_file_ops_service() -> FileOpsService:
+            return service
+
+        app.dependency_overrides[get_file_ops_service] = _override_file_ops_service
+
+    def _request(self, method: str, url: str, params: dict | None = None, payload: dict | None = None) -> httpx.Response:
+        async def _run() -> httpx.Response:
+            transport = httpx.ASGITransport(app=app)
+            async with httpx.AsyncClient(transport=transport, base_url="http://testserver") as client:
+                if method == "GET":
+                    return await client.get(url, params=params)
+                return await client.post(url, json=payload)
+
+        return asyncio.run(_run())
+
+    def test_edit_view_success(self) -> None:
+        file_path = self.root / "notes.txt"
+        file_path.write_text("hello", encoding="utf-8")
+
+        response = self._request("GET", "/api/files/view", params={"path": "storage1/notes.txt", "for_edit": "true"})
+
+        self.assertEqual(response.status_code, 200)
+        body = response.json()
+        self.assertEqual(body["path"], "storage1/notes.txt")
+        self.assertEqual(body["name"], "notes.txt")
+        self.assertEqual(body["content"], "hello")
+        self.assertFalse(body["truncated"])
+        self.assertIn("modified", body)
+
+    def test_save_success(self) -> None:
+        file_path = self.root / "notes.txt"
+        file_path.write_text("hello", encoding="utf-8")
+        initial = self._request("GET", "/api/files/view", params={"path": "storage1/notes.txt", "for_edit": "true"}).json()
+
+        response = self._request(
+            "POST",
+            "/api/files/save",
+            payload={
+                "path": "storage1/notes.txt",
+                "content": "changed",
+                "expected_modified": initial["modified"],
+            },
+        )
+
+        self.assertEqual(response.status_code, 200)
+        self.assertEqual(file_path.read_text(encoding="utf-8"), "changed")
+        self.assertEqual(response.json()["path"], "storage1/notes.txt")
+        self.assertEqual(response.json()["size"], len("changed".encode("utf-8")))
+
+    def test_unsupported_type(self) -> None:
+        (self.root / "report.pdf").write_bytes(b"%PDF-1.4")
+
+        response = self._request("GET", "/api/files/view", params={"path": "storage1/report.pdf", "for_edit": "true"})
+
+        self.assertEqual(response.status_code, 409)
+        self.assertEqual(response.json()["error"]["code"], "unsupported_type")
+
+    def test_directory_type_conflict(self) -> None:
+        (self.root / "docs").mkdir()
+
+        response = self._request("GET", "/api/files/view", params={"path": "storage1/docs", "for_edit": "true"})
+
+        self.assertEqual(response.status_code, 409)
+        self.assertEqual(response.json()["error"]["code"], "type_conflict")
+
+    def test_path_not_found(self) -> None:
+        response = self._request("POST", "/api/files/save", payload={"path": "storage1/missing.txt", "content": "x", "expected_modified": "2026-01-01T00:00:00Z"})
+
+        self.assertEqual(response.status_code, 404)
+        self.assertEqual(response.json()["error"]["code"], "path_not_found")
+
+    def test_traversal_attempt(self) -> None:
+        response = self._request("POST", "/api/files/save", payload={"path": "storage1/../etc/passwd", "content": "x", "expected_modified": "2026-01-01T00:00:00Z"})
+
+        self.assertEqual(response.status_code, 403)
+        self.assertEqual(response.json()["error"]["code"], "path_traversal_detected")
+
+    def test_conflict_when_file_changed(self) -> None:
+        file_path = self.root / "notes.txt"
+        file_path.write_text("hello", encoding="utf-8")
+        initial = self._request("GET", "/api/files/view", params={"path": "storage1/notes.txt", "for_edit": "true"}).json()
+        time.sleep(0.02)
+        file_path.write_text("changed elsewhere", encoding="utf-8")
+
+        response = self._request(
+            "POST",
+            "/api/files/save",
+            payload={
+                "path": "storage1/notes.txt",
+                "content": "local edit",
+                "expected_modified": initial["modified"],
+            },
+        )
+
+        self.assertEqual(response.status_code, 409)
+        self.assertEqual(response.json()["error"]["code"], "conflict")
+
+    def test_io_error_on_save_failure(self) -> None:
+        file_path = self.root / "notes.txt"
+        file_path.write_text("hello", encoding="utf-8")
+        initial = self._request("GET", "/api/files/view", params={"path": "storage1/notes.txt", "for_edit": "true"}).json()
+        self._set_service(FailingWriteFilesystemAdapter())
+
+        response = self._request(
+            "POST",
+            "/api/files/save",
+            payload={
+                "path": "storage1/notes.txt",
+                "content": "local edit",
+                "expected_modified": initial["modified"],
+            },
+        )
+
+        self.assertEqual(response.status_code, 500)
+        self.assertEqual(response.json()["error"]["code"], "io_error")
+
+    def test_file_too_large_for_edit(self) -> None:
+        content = "x" * (300 * 1024)
+        (self.root / "big.txt").write_text(content, encoding="utf-8")
+
+        response = self._request("GET", "/api/files/view", params={"path": "storage1/big.txt", "for_edit": "true"})
+
+        self.assertEqual(response.status_code, 409)
+        self.assertEqual(response.json()["error"]["code"], "file_too_large")
+
+
+if __name__ == "__main__":
+    unittest.main()

webui/backend/tests/golden/test_api_view_golden.py

@@ -49,18 +49,15 @@ class ViewApiGoldenTest(unittest.TestCase):
         response = self._request("storage1/notes.md")
 
         self.assertEqual(response.status_code, 200)
-        self.assertEqual(
-            response.json(),
-            {
-                "path": "storage1/notes.md",
-                "name": "notes.md",
-                "content_type": "text/markdown",
-                "encoding": "utf-8",
-                "truncated": False,
-                "size": len("# title\nhello\n".encode("utf-8")),
-                "content": "# title\nhello\n",
-            },
-        )
+        body = response.json()
+        self.assertEqual(body["path"], "storage1/notes.md")
+        self.assertEqual(body["name"], "notes.md")
+        self.assertEqual(body["content_type"], "text/markdown")
+        self.assertEqual(body["encoding"], "utf-8")
+        self.assertFalse(body["truncated"])
+        self.assertEqual(body["size"], len("# title\nhello\n".encode("utf-8")))
+        self.assertEqual(body["content"], "# title\nhello\n")
+        self.assertIn("modified", body)
 
     def test_view_unsupported_type(self) -> None:
         (self.root / "report.pdf").write_bytes(b"%PDF-1.4")

webui/backend/tests/golden/test_ui_smoke_golden.py

@@ -37,6 +37,10 @@ class UiSmokeGoldenTest(unittest.TestCase):
         self.assertIn('id="edit-btn"', body)
         self.assertIn('id="viewer-modal"', body)
         self.assertIn('id="viewer-content"', body)
+        self.assertIn('id="editor-modal"', body)
+        self.assertIn('id="editor-content"', body)
+        self.assertIn('id="editor-save-btn"', body)
+        self.assertIn('id="editor-cancel-btn"', body)
         self.assertIn('id="mkdir-btn"', body)
         self.assertIn('id="copy-btn"', body)
         self.assertIn('id="move-btn"', body)