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Reference for ultralytics/utils/downloads.py

Note

This file is available at https://github.com/ultralytics/ultralytics/blob/main/ultralytics/utils/downloads.py. If you spot a problem please help fix it by contributing a Pull Request 🛠️. Thank you 🙏!


ultralytics.utils.downloads.is_url

is_url(url, check=False)

Validates if the given string is a URL and optionally checks if the URL exists online.

Parameters:

Name Type Description Default
url str

The string to be validated as a URL.

required
check bool

If True, performs an additional check to see if the URL exists online. Defaults to False.

False

Returns:

Type Description
bool

Returns True for a valid URL. If 'check' is True, also returns True if the URL exists online. Returns False otherwise.

Example
valid = is_url("https://www.example.com")
Source code in ultralytics/utils/downloads.py
def is_url(url, check=False):
    """
    Validates if the given string is a URL and optionally checks if the URL exists online.

    Args:
        url (str): The string to be validated as a URL.
        check (bool, optional): If True, performs an additional check to see if the URL exists online.
            Defaults to False.

    Returns:
        (bool): Returns True for a valid URL. If 'check' is True, also returns True if the URL exists online.
            Returns False otherwise.

    Example:
        ```python
        valid = is_url("https://www.example.com")
        ```
    """
    try:
        url = str(url)
        result = parse.urlparse(url)
        assert all([result.scheme, result.netloc])  # check if is url
        if check:
            with request.urlopen(url) as response:
                return response.getcode() == 200  # check if exists online
        return True
    except Exception:
        return False





ultralytics.utils.downloads.delete_dsstore

delete_dsstore(path, files_to_delete=('.DS_Store', '__MACOSX'))

Deletes all ".DS_store" files under a specified directory.

Parameters:

Name Type Description Default
path str

The directory path where the ".DS_store" files should be deleted.

required
files_to_delete tuple

The files to be deleted.

('.DS_Store', '__MACOSX')
Example
from ultralytics.utils.downloads import delete_dsstore

delete_dsstore("path/to/dir")
Note

".DS_store" files are created by the Apple operating system and contain metadata about folders and files. They are hidden system files and can cause issues when transferring files between different operating systems.

Source code in ultralytics/utils/downloads.py
def delete_dsstore(path, files_to_delete=(".DS_Store", "__MACOSX")):
    """
    Deletes all ".DS_store" files under a specified directory.

    Args:
        path (str, optional): The directory path where the ".DS_store" files should be deleted.
        files_to_delete (tuple): The files to be deleted.

    Example:
        ```python
        from ultralytics.utils.downloads import delete_dsstore

        delete_dsstore("path/to/dir")
        ```

    Note:
        ".DS_store" files are created by the Apple operating system and contain metadata about folders and files. They
        are hidden system files and can cause issues when transferring files between different operating systems.
    """
    for file in files_to_delete:
        matches = list(Path(path).rglob(file))
        LOGGER.info(f"Deleting {file} files: {matches}")
        for f in matches:
            f.unlink()





ultralytics.utils.downloads.zip_directory

zip_directory(
    directory, compress=True, exclude=(".DS_Store", "__MACOSX"), progress=True
)

Zips the contents of a directory, excluding files containing strings in the exclude list. The resulting zip file is named after the directory and placed alongside it.

Parameters:

Name Type Description Default
directory str | Path

The path to the directory to be zipped.

required
compress bool

Whether to compress the files while zipping. Default is True.

True
exclude tuple

A tuple of filename strings to be excluded. Defaults to ('.DS_Store', '__MACOSX').

('.DS_Store', '__MACOSX')
progress bool

Whether to display a progress bar. Defaults to True.

True

Returns:

Type Description
Path

The path to the resulting zip file.

Example
from ultralytics.utils.downloads import zip_directory

file = zip_directory("path/to/dir")
Source code in ultralytics/utils/downloads.py
def zip_directory(directory, compress=True, exclude=(".DS_Store", "__MACOSX"), progress=True):
    """
    Zips the contents of a directory, excluding files containing strings in the exclude list. The resulting zip file is
    named after the directory and placed alongside it.

    Args:
        directory (str | Path): The path to the directory to be zipped.
        compress (bool): Whether to compress the files while zipping. Default is True.
        exclude (tuple, optional): A tuple of filename strings to be excluded. Defaults to ('.DS_Store', '__MACOSX').
        progress (bool, optional): Whether to display a progress bar. Defaults to True.

    Returns:
        (Path): The path to the resulting zip file.

    Example:
        ```python
        from ultralytics.utils.downloads import zip_directory

        file = zip_directory("path/to/dir")
        ```
    """
    from zipfile import ZIP_DEFLATED, ZIP_STORED, ZipFile

    delete_dsstore(directory)
    directory = Path(directory)
    if not directory.is_dir():
        raise FileNotFoundError(f"Directory '{directory}' does not exist.")

    # Unzip with progress bar
    files_to_zip = [f for f in directory.rglob("*") if f.is_file() and all(x not in f.name for x in exclude)]
    zip_file = directory.with_suffix(".zip")
    compression = ZIP_DEFLATED if compress else ZIP_STORED
    with ZipFile(zip_file, "w", compression) as f:
        for file in TQDM(files_to_zip, desc=f"Zipping {directory} to {zip_file}...", unit="file", disable=not progress):
            f.write(file, file.relative_to(directory))

    return zip_file  # return path to zip file





ultralytics.utils.downloads.unzip_file

unzip_file(
    file,
    path=None,
    exclude=(".DS_Store", "__MACOSX"),
    exist_ok=False,
    progress=True,
)

Unzips a *.zip file to the specified path, excluding files containing strings in the exclude list.

If the zipfile does not contain a single top-level directory, the function will create a new directory with the same name as the zipfile (without the extension) to extract its contents. If a path is not provided, the function will use the parent directory of the zipfile as the default path.

Parameters:

Name Type Description Default
file str

The path to the zipfile to be extracted.

required
path str

The path to extract the zipfile to. Defaults to None.

None
exclude tuple

A tuple of filename strings to be excluded. Defaults to ('.DS_Store', '__MACOSX').

('.DS_Store', '__MACOSX')
exist_ok bool

Whether to overwrite existing contents if they exist. Defaults to False.

False
progress bool

Whether to display a progress bar. Defaults to True.

True

Raises:

Type Description
BadZipFile

If the provided file does not exist or is not a valid zipfile.

Returns:

Type Description
Path

The path to the directory where the zipfile was extracted.

Example
from ultralytics.utils.downloads import unzip_file

dir = unzip_file("path/to/file.zip")
Source code in ultralytics/utils/downloads.py
def unzip_file(file, path=None, exclude=(".DS_Store", "__MACOSX"), exist_ok=False, progress=True):
    """
    Unzips a *.zip file to the specified path, excluding files containing strings in the exclude list.

    If the zipfile does not contain a single top-level directory, the function will create a new
    directory with the same name as the zipfile (without the extension) to extract its contents.
    If a path is not provided, the function will use the parent directory of the zipfile as the default path.

    Args:
        file (str): The path to the zipfile to be extracted.
        path (str, optional): The path to extract the zipfile to. Defaults to None.
        exclude (tuple, optional): A tuple of filename strings to be excluded. Defaults to ('.DS_Store', '__MACOSX').
        exist_ok (bool, optional): Whether to overwrite existing contents if they exist. Defaults to False.
        progress (bool, optional): Whether to display a progress bar. Defaults to True.

    Raises:
        BadZipFile: If the provided file does not exist or is not a valid zipfile.

    Returns:
        (Path): The path to the directory where the zipfile was extracted.

    Example:
        ```python
        from ultralytics.utils.downloads import unzip_file

        dir = unzip_file("path/to/file.zip")
        ```
    """
    from zipfile import BadZipFile, ZipFile, is_zipfile

    if not (Path(file).exists() and is_zipfile(file)):
        raise BadZipFile(f"File '{file}' does not exist or is a bad zip file.")
    if path is None:
        path = Path(file).parent  # default path

    # Unzip the file contents
    with ZipFile(file) as zipObj:
        files = [f for f in zipObj.namelist() if all(x not in f for x in exclude)]
        top_level_dirs = {Path(f).parts[0] for f in files}

        # Decide to unzip directly or unzip into a directory
        unzip_as_dir = len(top_level_dirs) == 1  # (len(files) > 1 and not files[0].endswith("/"))
        if unzip_as_dir:
            # Zip has 1 top-level directory
            extract_path = path  # i.e. ../datasets
            path = Path(path) / list(top_level_dirs)[0]  # i.e. extract coco8/ dir to ../datasets/
        else:
            # Zip has multiple files at top level
            path = extract_path = Path(path) / Path(file).stem  # i.e. extract multiple files to ../datasets/coco8/

        # Check if destination directory already exists and contains files
        if path.exists() and any(path.iterdir()) and not exist_ok:
            # If it exists and is not empty, return the path without unzipping
            LOGGER.warning(f"WARNING ⚠️ Skipping {file} unzip as destination directory {path} is not empty.")
            return path

        for f in TQDM(files, desc=f"Unzipping {file} to {Path(path).resolve()}...", unit="file", disable=not progress):
            # Ensure the file is within the extract_path to avoid path traversal security vulnerability
            if ".." in Path(f).parts:
                LOGGER.warning(f"Potentially insecure file path: {f}, skipping extraction.")
                continue
            zipObj.extract(f, extract_path)

    return path  # return unzip dir





ultralytics.utils.downloads.check_disk_space

check_disk_space(
    url="https://ultralytics.com/assets/coco8.zip",
    path=Path.cwd(),
    sf=1.5,
    hard=True,
)

Check if there is sufficient disk space to download and store a file.

Parameters:

Name Type Description Default
url str

The URL to the file. Defaults to 'https://ultralytics.com/assets/coco8.zip'.

'https://ultralytics.com/assets/coco8.zip'
path str | Path

The path or drive to check the available free space on.

cwd()
sf float

Safety factor, the multiplier for the required free space. Defaults to 1.5.

1.5
hard bool

Whether to throw an error or not on insufficient disk space. Defaults to True.

True

Returns:

Type Description
bool

True if there is sufficient disk space, False otherwise.

Source code in ultralytics/utils/downloads.py
def check_disk_space(url="https://ultralytics.com/assets/coco8.zip", path=Path.cwd(), sf=1.5, hard=True):
    """
    Check if there is sufficient disk space to download and store a file.

    Args:
        url (str, optional): The URL to the file. Defaults to 'https://ultralytics.com/assets/coco8.zip'.
        path (str | Path, optional): The path or drive to check the available free space on.
        sf (float, optional): Safety factor, the multiplier for the required free space. Defaults to 1.5.
        hard (bool, optional): Whether to throw an error or not on insufficient disk space. Defaults to True.

    Returns:
        (bool): True if there is sufficient disk space, False otherwise.
    """
    try:
        r = requests.head(url)  # response
        assert r.status_code < 400, f"URL error for {url}: {r.status_code} {r.reason}"  # check response
    except Exception:
        return True  # requests issue, default to True

    # Check file size
    gib = 1 << 30  # bytes per GiB
    data = int(r.headers.get("Content-Length", 0)) / gib  # file size (GB)
    total, used, free = (x / gib for x in shutil.disk_usage(path))  # bytes

    if data * sf < free:
        return True  # sufficient space

    # Insufficient space
    text = (
        f"WARNING ⚠️ Insufficient free disk space {free:.1f} GB < {data * sf:.3f} GB required, "
        f"Please free {data * sf - free:.1f} GB additional disk space and try again."
    )
    if hard:
        raise MemoryError(text)
    LOGGER.warning(text)
    return False





ultralytics.utils.downloads.get_google_drive_file_info

get_google_drive_file_info(link)

Retrieves the direct download link and filename for a shareable Google Drive file link.

Parameters:

Name Type Description Default
link str

The shareable link of the Google Drive file.

required

Returns:

Type Description
str

Direct download URL for the Google Drive file.

str

Original filename of the Google Drive file. If filename extraction fails, returns None.

Example
from ultralytics.utils.downloads import get_google_drive_file_info

link = "https://drive.google.com/file/d/1cqT-cJgANNrhIHCrEufUYhQ4RqiWG_lJ/view?usp=drive_link"
url, filename = get_google_drive_file_info(link)
Source code in ultralytics/utils/downloads.py
def get_google_drive_file_info(link):
    """
    Retrieves the direct download link and filename for a shareable Google Drive file link.

    Args:
        link (str): The shareable link of the Google Drive file.

    Returns:
        (str): Direct download URL for the Google Drive file.
        (str): Original filename of the Google Drive file. If filename extraction fails, returns None.

    Example:
        ```python
        from ultralytics.utils.downloads import get_google_drive_file_info

        link = "https://drive.google.com/file/d/1cqT-cJgANNrhIHCrEufUYhQ4RqiWG_lJ/view?usp=drive_link"
        url, filename = get_google_drive_file_info(link)
        ```
    """
    file_id = link.split("/d/")[1].split("/view")[0]
    drive_url = f"https://drive.google.com/uc?export=download&id={file_id}"
    filename = None

    # Start session
    with requests.Session() as session:
        response = session.get(drive_url, stream=True)
        if "quota exceeded" in str(response.content.lower()):
            raise ConnectionError(
                emojis(
                    f"❌  Google Drive file download quota exceeded. "
                    f"Please try again later or download this file manually at {link}."
                )
            )
        for k, v in response.cookies.items():
            if k.startswith("download_warning"):
                drive_url += f"&confirm={v}"  # v is token
        cd = response.headers.get("content-disposition")
        if cd:
            filename = re.findall('filename="(.+)"', cd)[0]
    return drive_url, filename





ultralytics.utils.downloads.safe_download

safe_download(
    url,
    file=None,
    dir=None,
    unzip=True,
    delete=False,
    curl=False,
    retry=3,
    min_bytes=1.0,
    exist_ok=False,
    progress=True,
)

Downloads files from a URL, with options for retrying, unzipping, and deleting the downloaded file.

Parameters:

Name Type Description Default
url str

The URL of the file to be downloaded.

required
file str

The filename of the downloaded file. If not provided, the file will be saved with the same name as the URL.

None
dir str

The directory to save the downloaded file. If not provided, the file will be saved in the current working directory.

None
unzip bool

Whether to unzip the downloaded file. Default: True.

True
delete bool

Whether to delete the downloaded file after unzipping. Default: False.

False
curl bool

Whether to use curl command line tool for downloading. Default: False.

False
retry int

The number of times to retry the download in case of failure. Default: 3.

3
min_bytes float

The minimum number of bytes that the downloaded file should have, to be considered a successful download. Default: 1E0.

1.0
exist_ok bool

Whether to overwrite existing contents during unzipping. Defaults to False.

False
progress bool

Whether to display a progress bar during the download. Default: True.

True
Example
from ultralytics.utils.downloads import safe_download

link = "https://ultralytics.com/assets/bus.jpg"
path = safe_download(link)
Source code in ultralytics/utils/downloads.py
def safe_download(
    url,
    file=None,
    dir=None,
    unzip=True,
    delete=False,
    curl=False,
    retry=3,
    min_bytes=1e0,
    exist_ok=False,
    progress=True,
):
    """
    Downloads files from a URL, with options for retrying, unzipping, and deleting the downloaded file.

    Args:
        url (str): The URL of the file to be downloaded.
        file (str, optional): The filename of the downloaded file.
            If not provided, the file will be saved with the same name as the URL.
        dir (str, optional): The directory to save the downloaded file.
            If not provided, the file will be saved in the current working directory.
        unzip (bool, optional): Whether to unzip the downloaded file. Default: True.
        delete (bool, optional): Whether to delete the downloaded file after unzipping. Default: False.
        curl (bool, optional): Whether to use curl command line tool for downloading. Default: False.
        retry (int, optional): The number of times to retry the download in case of failure. Default: 3.
        min_bytes (float, optional): The minimum number of bytes that the downloaded file should have, to be considered
            a successful download. Default: 1E0.
        exist_ok (bool, optional): Whether to overwrite existing contents during unzipping. Defaults to False.
        progress (bool, optional): Whether to display a progress bar during the download. Default: True.

    Example:
        ```python
        from ultralytics.utils.downloads import safe_download

        link = "https://ultralytics.com/assets/bus.jpg"
        path = safe_download(link)
        ```
    """
    gdrive = url.startswith("https://drive.google.com/")  # check if the URL is a Google Drive link
    if gdrive:
        url, file = get_google_drive_file_info(url)

    f = Path(dir or ".") / (file or url2file(url))  # URL converted to filename
    if "://" not in str(url) and Path(url).is_file():  # URL exists ('://' check required in Windows Python<3.10)
        f = Path(url)  # filename
    elif not f.is_file():  # URL and file do not exist
        uri = (url if gdrive else clean_url(url)).replace(  # cleaned and aliased url
            "https://github.com/ultralytics/assets/releases/download/v0.0.0/",
            "https://ultralytics.com/assets/",  # assets alias
        )
        desc = f"Downloading {uri} to '{f}'"
        LOGGER.info(f"{desc}...")
        f.parent.mkdir(parents=True, exist_ok=True)  # make directory if missing
        check_disk_space(url, path=f.parent)
        for i in range(retry + 1):
            try:
                if curl or i > 0:  # curl download with retry, continue
                    s = "sS" * (not progress)  # silent
                    r = subprocess.run(["curl", "-#", f"-{s}L", url, "-o", f, "--retry", "3", "-C", "-"]).returncode
                    assert r == 0, f"Curl return value {r}"
                else:  # urllib download
                    method = "torch"
                    if method == "torch":
                        torch.hub.download_url_to_file(url, f, progress=progress)
                    else:
                        with request.urlopen(url) as response, TQDM(
                            total=int(response.getheader("Content-Length", 0)),
                            desc=desc,
                            disable=not progress,
                            unit="B",
                            unit_scale=True,
                            unit_divisor=1024,
                        ) as pbar:
                            with open(f, "wb") as f_opened:
                                for data in response:
                                    f_opened.write(data)
                                    pbar.update(len(data))

                if f.exists():
                    if f.stat().st_size > min_bytes:
                        break  # success
                    f.unlink()  # remove partial downloads
            except Exception as e:
                if i == 0 and not is_online():
                    raise ConnectionError(emojis(f"❌  Download failure for {uri}. Environment is not online.")) from e
                elif i >= retry:
                    raise ConnectionError(emojis(f"❌  Download failure for {uri}. Retry limit reached.")) from e
                LOGGER.warning(f"⚠️ Download failure, retrying {i + 1}/{retry} {uri}...")

    if unzip and f.exists() and f.suffix in {"", ".zip", ".tar", ".gz"}:
        from zipfile import is_zipfile

        unzip_dir = (dir or f.parent).resolve()  # unzip to dir if provided else unzip in place
        if is_zipfile(f):
            unzip_dir = unzip_file(file=f, path=unzip_dir, exist_ok=exist_ok, progress=progress)  # unzip
        elif f.suffix in {".tar", ".gz"}:
            LOGGER.info(f"Unzipping {f} to {unzip_dir}...")
            subprocess.run(["tar", "xf" if f.suffix == ".tar" else "xfz", f, "--directory", unzip_dir], check=True)
        if delete:
            f.unlink()  # remove zip
        return unzip_dir





ultralytics.utils.downloads.get_github_assets

get_github_assets(repo='ultralytics/assets', version='latest', retry=False)

Retrieve the specified version's tag and assets from a GitHub repository. If the version is not specified, the function fetches the latest release assets.

Parameters:

Name Type Description Default
repo str

The GitHub repository in the format 'owner/repo'. Defaults to 'ultralytics/assets'.

'ultralytics/assets'
version str

The release version to fetch assets from. Defaults to 'latest'.

'latest'
retry bool

Flag to retry the request in case of a failure. Defaults to False.

False

Returns:

Type Description
tuple

A tuple containing the release tag and a list of asset names.

Example
tag, assets = get_github_assets(repo="ultralytics/assets", version="latest")
Source code in ultralytics/utils/downloads.py
def get_github_assets(repo="ultralytics/assets", version="latest", retry=False):
    """
    Retrieve the specified version's tag and assets from a GitHub repository. If the version is not specified, the
    function fetches the latest release assets.

    Args:
        repo (str, optional): The GitHub repository in the format 'owner/repo'. Defaults to 'ultralytics/assets'.
        version (str, optional): The release version to fetch assets from. Defaults to 'latest'.
        retry (bool, optional): Flag to retry the request in case of a failure. Defaults to False.

    Returns:
        (tuple): A tuple containing the release tag and a list of asset names.

    Example:
        ```python
        tag, assets = get_github_assets(repo="ultralytics/assets", version="latest")
        ```
    """
    if version != "latest":
        version = f"tags/{version}"  # i.e. tags/v6.2
    url = f"https://api.github.com/repos/{repo}/releases/{version}"
    r = requests.get(url)  # github api
    if r.status_code != 200 and r.reason != "rate limit exceeded" and retry:  # failed and not 403 rate limit exceeded
        r = requests.get(url)  # try again
    if r.status_code != 200:
        LOGGER.warning(f"⚠️ GitHub assets check failure for {url}: {r.status_code} {r.reason}")
        return "", []
    data = r.json()
    return data["tag_name"], [x["name"] for x in data["assets"]]  # tag, assets i.e. ['yolov8n.pt', 'yolov8s.pt', ...]





ultralytics.utils.downloads.attempt_download_asset

attempt_download_asset(
    file, repo="ultralytics/assets", release="v8.3.0", **kwargs
)

Attempt to download a file from GitHub release assets if it is not found locally. The function checks for the file locally first, then tries to download it from the specified GitHub repository release.

Parameters:

Name Type Description Default
file str | Path

The filename or file path to be downloaded.

required
repo str

The GitHub repository in the format 'owner/repo'. Defaults to 'ultralytics/assets'.

'ultralytics/assets'
release str

The specific release version to be downloaded. Defaults to 'v8.3.0'.

'v8.3.0'
**kwargs any

Additional keyword arguments for the download process.

{}

Returns:

Type Description
str

The path to the downloaded file.

Example
file_path = attempt_download_asset("yolo11n.pt", repo="ultralytics/assets", release="latest")
Source code in ultralytics/utils/downloads.py
def attempt_download_asset(file, repo="ultralytics/assets", release="v8.3.0", **kwargs):
    """
    Attempt to download a file from GitHub release assets if it is not found locally. The function checks for the file
    locally first, then tries to download it from the specified GitHub repository release.

    Args:
        file (str | Path): The filename or file path to be downloaded.
        repo (str, optional): The GitHub repository in the format 'owner/repo'. Defaults to 'ultralytics/assets'.
        release (str, optional): The specific release version to be downloaded. Defaults to 'v8.3.0'.
        **kwargs (any): Additional keyword arguments for the download process.

    Returns:
        (str): The path to the downloaded file.

    Example:
        ```python
        file_path = attempt_download_asset("yolo11n.pt", repo="ultralytics/assets", release="latest")
        ```
    """
    from ultralytics.utils import SETTINGS  # scoped for circular import

    # YOLOv3/5u updates
    file = str(file)
    file = checks.check_yolov5u_filename(file)
    file = Path(file.strip().replace("'", ""))
    if file.exists():
        return str(file)
    elif (SETTINGS["weights_dir"] / file).exists():
        return str(SETTINGS["weights_dir"] / file)
    else:
        # URL specified
        name = Path(parse.unquote(str(file))).name  # decode '%2F' to '/' etc.
        download_url = f"https://github.com/{repo}/releases/download"
        if str(file).startswith(("http:/", "https:/")):  # download
            url = str(file).replace(":/", "://")  # Pathlib turns :// -> :/
            file = url2file(name)  # parse authentication https://url.com/file.txt?auth...
            if Path(file).is_file():
                LOGGER.info(f"Found {clean_url(url)} locally at {file}")  # file already exists
            else:
                safe_download(url=url, file=file, min_bytes=1e5, **kwargs)

        elif repo == GITHUB_ASSETS_REPO and name in GITHUB_ASSETS_NAMES:
            safe_download(url=f"{download_url}/{release}/{name}", file=file, min_bytes=1e5, **kwargs)

        else:
            tag, assets = get_github_assets(repo, release)
            if not assets:
                tag, assets = get_github_assets(repo)  # latest release
            if name in assets:
                safe_download(url=f"{download_url}/{tag}/{name}", file=file, min_bytes=1e5, **kwargs)

        return str(file)





ultralytics.utils.downloads.download

download(
    url,
    dir=Path.cwd(),
    unzip=True,
    delete=False,
    curl=False,
    threads=1,
    retry=3,
    exist_ok=False,
)

Downloads files from specified URLs to a given directory. Supports concurrent downloads if multiple threads are specified.

Parameters:

Name Type Description Default
url str | list

The URL or list of URLs of the files to be downloaded.

required
dir Path

The directory where the files will be saved. Defaults to the current working directory.

cwd()
unzip bool

Flag to unzip the files after downloading. Defaults to True.

True
delete bool

Flag to delete the zip files after extraction. Defaults to False.

False
curl bool

Flag to use curl for downloading. Defaults to False.

False
threads int

Number of threads to use for concurrent downloads. Defaults to 1.

1
retry int

Number of retries in case of download failure. Defaults to 3.

3
exist_ok bool

Whether to overwrite existing contents during unzipping. Defaults to False.

False
Example
download("https://ultralytics.com/assets/example.zip", dir="path/to/dir", unzip=True)
Source code in ultralytics/utils/downloads.py
def download(url, dir=Path.cwd(), unzip=True, delete=False, curl=False, threads=1, retry=3, exist_ok=False):
    """
    Downloads files from specified URLs to a given directory. Supports concurrent downloads if multiple threads are
    specified.

    Args:
        url (str | list): The URL or list of URLs of the files to be downloaded.
        dir (Path, optional): The directory where the files will be saved. Defaults to the current working directory.
        unzip (bool, optional): Flag to unzip the files after downloading. Defaults to True.
        delete (bool, optional): Flag to delete the zip files after extraction. Defaults to False.
        curl (bool, optional): Flag to use curl for downloading. Defaults to False.
        threads (int, optional): Number of threads to use for concurrent downloads. Defaults to 1.
        retry (int, optional): Number of retries in case of download failure. Defaults to 3.
        exist_ok (bool, optional): Whether to overwrite existing contents during unzipping. Defaults to False.

    Example:
        ```python
        download("https://ultralytics.com/assets/example.zip", dir="path/to/dir", unzip=True)
        ```
    """
    dir = Path(dir)
    dir.mkdir(parents=True, exist_ok=True)  # make directory
    if threads > 1:
        with ThreadPool(threads) as pool:
            pool.map(
                lambda x: safe_download(
                    url=x[0],
                    dir=x[1],
                    unzip=unzip,
                    delete=delete,
                    curl=curl,
                    retry=retry,
                    exist_ok=exist_ok,
                    progress=threads <= 1,
                ),
                zip(url, repeat(dir)),
            )
            pool.close()
            pool.join()
    else:
        for u in [url] if isinstance(url, (str, Path)) else url:
            safe_download(url=u, dir=dir, unzip=unzip, delete=delete, curl=curl, retry=retry, exist_ok=exist_ok)



📅 Created 1 year ago ✏️ Updated 2 months ago