Add overwrite option to prepare

doc/source/conf.py

@@ -23,7 +23,7 @@
 author = "Bradley Steinfeld, Sam Prokopchuk, James Reeve"
 
 # The full version, including alpha/beta/rc tags
-release = "0.20.3"
+release = "0.20.4"
 
 
 # -- General configuration ---------------------------------------------------

skillsnetwork/core.py

@@ -114,16 +114,27 @@ async def _get_chunks(url: str, chunk_size: int) -> Generator[bytes, None, None]
             raise Exception(f"Failed to read dataset at {url}") from None
 
 
-def _verify_files_dont_exist(paths: Iterable[Union[str, Path]]) -> None:
+def _verify_files_dont_exist(
+    paths: Iterable[Union[str, Path]], remove_if_exist: bool = False
+) -> None:
     """
     Verifies all paths in 'paths' don't exist.
     :param paths: A iterable of strs or pathlib.Paths.
+    :param remove_if_exist=False: Removes file at path if they already exist.
     :returns: None
     :raises FileExistsError: On the first path found that already exists.
     """
     for path in paths:
-        if Path(path).exists():
-            raise FileExistsError(f"Error: File '{path}' already exists.")
+        path = Path(path)
+        if path.exists():
+            if remove_if_exist:
+                if path.is_symlink():
+                    realpath = path.resolve()
+                    path.unlink(realpath)
+                else:
+                    shutil.rmtree(path)
+            else:
+                raise FileExistsError(f"Error: File '{path}' already exists.")
 
 
 def _is_file_to_symlink(path: Path) -> bool:
@@ -188,7 +199,9 @@ async def read(url: str, chunk_size: int = DEFAULT_CHUNK_SIZE) -> bytes:
     return b"".join([chunk async for chunk in _get_chunks(url, chunk_size)])
 
 
-async def prepare(url: str, path: Optional[str] = None, verbose: bool = True) -> None:
+async def prepare(
+    url: str, path: Optional[str] = None, verbose: bool = True, overwrite: bool = False
+) -> None:
     """
     Prepares a dataset for learners. Downloads a dataset from the given url,
     decompresses it if necessary. If not using jupyterlite, will extract to
@@ -200,6 +213,8 @@ async def prepare(url: str, path: Optional[str] = None, verbose: bool = True) ->
 
     :param url: The URL to download the dataset from.
     :param path: The path the dataset will be available at. Current working directory by default.
+    :param verbose=True: Prints saved path if True.
+    :param overwrite=False: Overwrites any existing files at destination if they exist.
     :raise InvalidURLException: When URL is invalid.
     :raise FileExistsError: it raises this when a file to be symlinked already exists.
     :raise ValueError: When requested path is in /tmp, or cannot be saved to path.
@@ -239,7 +254,8 @@ async def prepare(url: str, path: Optional[str] = None, verbose: bool = True) ->
                     path / child.name
                     for child in map(Path, tf.getnames())
                     if len(child.parents) == 1 and _is_file_to_symlink(child)
-                ]
+                ],
+                overwrite,
             )  # Only check if top-level fileobject
             pbar = tqdm(iterable=tf.getmembers(), total=len(tf.getmembers()))
             pbar.set_description(f"Extracting {filename}")
@@ -253,15 +269,16 @@ async def prepare(url: str, path: Optional[str] = None, verbose: bool = True) ->
                     path / child.name
                     for child in map(Path, zf.namelist())
                     if len(child.parents) == 1 and _is_file_to_symlink(child)
-                ]
+                ],
+                overwrite,
             )
             pbar = tqdm(iterable=zf.infolist(), total=len(zf.infolist()))
             pbar.set_description(f"Extracting {filename}")
             for member in pbar:
                 zf.extract(member=member, path=extract_dir)
         tmp_download_file.unlink()
     else:
-        _verify_files_dont_exist([path / filename])
+        _verify_files_dont_exist([path / filename], overwrite)
         shutil.move(tmp_download_file, extract_dir / filename)
 
     # If in jupyterlite environment, the extract_dir = path, so the files are already there.
@@ -274,8 +291,36 @@ async def prepare(url: str, path: Optional[str] = None, verbose: bool = True) ->
         print(f"Saved to '{relpath(path.resolve())}'")
 
 
-if _is_jupyterlite():
-    tqdm.monitor_interval = 0
+def setup() -> None:
+    if _is_jupyterlite():
+        tqdm.monitor_interval = 0
+
+    try:
+        import sys  # pyright: ignore
+
+        ipython = get_ipython()
+
+        def hide_traceback(
+            exc_tuple=None,
+            filename=None,
+            tb_offset=None,
+            exception_only=False,
+            running_compiled_code=False,
+        ):
+            etype, value, tb = sys.exc_info()
+            value.__cause__ = None  # suppress chained exceptions
+            return ipython._showtraceback(
+                etype, value, ipython.InteractiveTB.get_exception_only(etype, value)
+            )
+
+        ipython.showtraceback = hide_traceback
+
+    except NameError:
+        pass
+
+
+setup()
+
 
 # For backwards compatibility
 download_dataset = download