usgs_download.py 文件源码

def download_image(url, output_dir, image, creds):
    cookies = HTTPCookieProcessor()
    opener = build_opener(cookies)
    install_opener(opener)

    data = urlopen("https://ers.cr.usgs.gov").read().decode('utf-8')
    m = re.search(r'<input .*?name="csrf_token".*?value="(.*?)"', data)
    if m:
        token = m.group(1)
    else:
        print("Error : CSRF_Token not found")

    params = urlencode(dict(username=creds['account'], password=creds['passwd'], csrf_token=token))
    params = params.encode('ascii')
    request = Request("https://ers.cr.usgs.gov/login", params, headers={})
    f = urlopen(request)

    data = f.read().decode('utf-8')
    f.close()
    if data.find('You must sign in as a registered user to download data or place orders for USGS EROS products') > 0:
        print("Authentification failed")

    req = urlopen(url)

    uri = req.url
    response = requests.get(uri)

    if response.status_code == 200:
        with open(os.path.join(output_dir, image), 'wb') as f:
            for chunk in response.iter_content(chunk_size=1024 * 1024 * 8):
                f.write(chunk)

    elif response.status_code > 399:
        print('Code {}'.format(response.status_code))
        raise BadRequestsResponse(Exception)