Support optional hash output in save method

jupyter_server/services/contents/filemanager.py

@@ -475,8 +475,14 @@ def _save_directory(self, os_path, model, path=""):
         else:
             self.log.debug("Directory %r already exists", os_path)
 
-    def save(self, model, path=""):
-        """Save the file model and return the model with no content."""
+    def save(self, model, path="", require_hash=False):
+        """Save the file model and return the model with no content.
+
+        Parameters
+        ----------
+        require_hash: bool, optional
+            Whether to include the hash of the file contents.
+        """
         path = path.strip("/")
 
         self.run_pre_save_hooks(model=model, path=path)
@@ -519,7 +525,7 @@ def save(self, model, path=""):
             self.validate_notebook_model(model, validation_error=validation_error)
             validation_message = model.get("message", None)
 
-        model = self.get(path, content=False)
+        model = self.get(path, content=False, require_hash=require_hash)
         if validation_message:
             model["message"] = validation_message
 
@@ -941,8 +947,14 @@ async def _save_directory(self, os_path, model, path=""):
         else:
             self.log.debug("Directory %r already exists", os_path)
 
-    async def save(self, model, path=""):
-        """Save the file model and return the model with no content."""
+    async def save(self, model, path="", require_hash=False):
+        """Save the file model and return the model with no content.
+
+        Parameters
+        ----------
+        require_hash: bool, optional
+            Whether to include the hash of the file contents.
+        """
         path = path.strip("/")
 
         self.run_pre_save_hooks(model=model, path=path)
@@ -982,7 +994,7 @@ async def save(self, model, path=""):
             self.validate_notebook_model(model, validation_error=validation_error)
             validation_message = model.get("message", None)
 
-        model = await self.get(path, content=False)
+        model = await self.get(path, content=False, require_hash=require_hash)
         if validation_message:
             model["message"] = validation_message
 

jupyter_server/services/contents/handlers.py

@@ -238,12 +238,14 @@ async def _new_untitled(self, path, type="", ext=""):
         validate_model(model)
         self._finish_model(model)
 
-    async def _save(self, model, path):
+    async def _save(self, model, path, require_hash):
         """Save an existing file."""
         chunk = model.get("chunk", None)
         if not chunk or chunk == -1:  # Avoid tedious log information
             self.log.info("Saving file at %s", path)
-        model = await ensure_async(self.contents_manager.save(model, path))
+        model = await ensure_async(
+            self.contents_manager.save(model, path, require_hash=require_hash)
+        )
         validate_model(model)
         self._finish_model(model)
 
@@ -304,6 +306,13 @@ async def put(self, path=""):
         model = self.get_json_body()
         cm = self.contents_manager
 
+        hash_str = self.get_query_argument("hash", default="0")
+        if hash_str not in {"0", "1"}:
+            raise web.HTTPError(
+                400, f"Hash argument {hash_str!r} is invalid. It must be '0' or '1'."
+            )
+        require_hash = int(hash_str)
+
         if model:
             if model.get("copy_from"):
                 raise web.HTTPError(400, "Cannot copy with PUT, only POST")
@@ -318,7 +327,7 @@ async def put(self, path=""):
                 # fall back to file if unknown type
                 model["type"] = "file"
             if exists:
-                await self._save(model, path)
+                await self._save(model, path, require_hash=require_hash)
             else:
                 await self._upload(model, path)
         else:

jupyter_server/services/contents/largefilemanager.py

@@ -13,8 +13,14 @@
 class LargeFileManager(FileContentsManager):
     """Handle large file upload."""
 
-    def save(self, model, path=""):
-        """Save the file model and return the model with no content."""
+    def save(self, model, path="", require_hash=False):
+        """Save the file model and return the model with no content.
+
+        Parameters
+        ----------
+        require_hash: bool, optional
+            Whether to include the hash of the file contents.
+        """
         chunk = model.get("chunk", None)
         if chunk is not None:
             path = path.strip("/")
@@ -49,15 +55,15 @@ def save(self, model, path=""):
                 self.log.error("Error while saving file: %s %s", path, e, exc_info=True)
                 raise web.HTTPError(500, f"Unexpected error while saving file: {path} {e}") from e
 
-            model = self.get(path, content=False)
+            model = self.get(path, content=False, require_hash=require_hash)
 
             # Last chunk
             if chunk == -1:
                 self.run_post_save_hooks(model=model, os_path=os_path)
             self.emit(data={"action": "save", "path": path})
             return model
         else:
-            return super().save(model, path)
+            return super().save(model, path, require_hash=require_hash)
 
     def _save_large_file(self, os_path, content, format):
         """Save content of a generic file."""
@@ -85,8 +91,14 @@ def _save_large_file(self, os_path, content, format):
 class AsyncLargeFileManager(AsyncFileContentsManager):
     """Handle large file upload asynchronously"""
 
-    async def save(self, model, path=""):
-        """Save the file model and return the model with no content."""
+    async def save(self, model, path="", require_hash=False):
+        """Save the file model and return the model with no content.
+
+        Parameters
+        ----------
+        require_hash: bool, optional
+            Whether to include the hash of the file contents.
+        """
         chunk = model.get("chunk", None)
         if chunk is not None:
             path = path.strip("/")
@@ -121,7 +133,7 @@ async def save(self, model, path=""):
                 self.log.error("Error while saving file: %s %s", path, e, exc_info=True)
                 raise web.HTTPError(500, f"Unexpected error while saving file: {path} {e}") from e
 
-            model = await self.get(path, content=False)
+            model = await self.get(path, content=False, require_hash=require_hash)
 
             # Last chunk
             if chunk == -1:
@@ -130,7 +142,7 @@ async def save(self, model, path=""):
             self.emit(data={"action": "save", "path": path})
             return model
         else:
-            return await super().save(model, path)
+            return await super().save(model, path, require_hash=require_hash)
 
     async def _save_large_file(self, os_path, content, format):
         """Save content of a generic file."""

jupyter_server/services/contents/manager.py

@@ -460,10 +460,15 @@ def get(self, path, content=True, type=None, format=None, require_hash=False):
         """
         raise NotImplementedError
 
-    def save(self, model, path):
+    def save(self, model, path, require_hash=False):
         """
         Save a file or directory model to path.
 
+        Parameters
+        ----------
+        require_hash : bool
+            Whether the file hash must be returned or not.
+
         Should return the saved model with no content.  Save implementations
         should call self.run_pre_save_hook(model=model, path=path) prior to
         writing any data.
@@ -870,10 +875,15 @@ async def get(self, path, content=True, type=None, format=None, require_hash=Fal
         """
         raise NotImplementedError
 
-    async def save(self, model, path):
+    async def save(self, model, path, require_hash=False):
         """
         Save a file or directory model to path.
 
+        Parameters
+        ----------
+        require_hash : bool
+            Whether the file hash must be returned or not.
+
         Should return the saved model with no content.  Save implementations
         should call self.run_pre_save_hook(model=model, path=path) prior to
         writing any data.