Authentication

HTTP authentication

Use the HTTPDownloader class directly to provide login credentials to HTTP servers that require basic authentication. For example:

from pooch import HTTPDownloader


def fetch_protected_data():
    """
    Fetch a file from a server that requires authentication
    """
    # Let the downloader know the login credentials
    download_auth = HTTPDownloader(auth=("my_username", "my_password"))
    fname = GOODBOY.fetch("some-data.csv", downloader=download_auth)
    data = pandas.read_csv(fname)
    return data

It’s probably not a good idea to hard-code credentials in your code. One way around this is to ask users to set their own credentials through environment variables. The download code could look something like so:

import os


def fetch_protected_data():
    """
    Fetch a file from a server that requires authentication
    """
    # Get the credentials from the user's environment
    username = os.environ.get("SOMESITE_USERNAME")
    password = os.environ.get("SOMESITE_PASSWORD")
    # Let the downloader know the login credentials
    download_auth = HTTPDownloader(auth=(username, password))
    fname = GOODBOY.fetch("some-data.csv", downloader=download_auth)
    data = pandas.read_csv(fname)
    return data

FTP/SFTP with authentication

Pooch also comes with the FTPDownloader and SFTPDownloader downloaders that can be used when files are distributed over FTP or SFTP (secure FTP).

Note

To download files over SFTP, paramiko needs to be installed.

Sometimes the FTP server doesn’t support anonymous FTP and needs authentication or uses a non-default port. In these cases, pass in the downloader class explicitly (works with both FTP and SFTP):

import os


def fetch_c137():
    """
    Load the C-137 sample data as a pandas.DataFrame (over FTP this time).
    """
    username = os.environ.get("MYDATASERVER_USERNAME")
    password = os.environ.get("MYDATASERVER_PASSWORD")
    download_ftp = pooch.FTPDownloader(username=username, password=password)
    fname = GOODBOY.fetch("c137.csv", downloader=download_ftp)
    data = pandas.read_csv(fname)
    return data