无法使用 add-apt-repository 添加 PPA：SSL 支持不可用

Question

每当我尝试添加任何 PPA 来安装任何东西时，都会出现以下错误：

nikunj@nikunj-DL-H61MXE-V:~$ sudo add-apt-repository ppa:ravefinity-project/ppa
Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 326, in get_ppa_info
    ret = get_ppa_info_from_lp(user, ppa)
  File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 91, in get_ppa_info_from_lp
    return get_info_from_lp(lp_url)
  File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 87, in get_info_from_lp
    return _get_https_content_py3(lp_url)
  File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 101, in _get_https_content_py3
    lp_page = urllib.request.urlopen(request, cafile=LAUNCHPAD_PPA_CERT)
  File "/usr/lib/python3.4/urllib/request.py", line 148, in urlopen
    raise ValueError('SSL support not available')
ValueError: SSL support not available

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "/usr/bin/add-apt-repository", line 122, in <module>
    shortcut = shortcut_handler(line)
  File "/usr/lib/python3/dist-packages/softwareproperties/SoftwareProperties.py", line 841, in shortcut_handler
    ret = factory(shortcut)
  File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 391, in shortcut_handler
    return PPAShortcutHandler(shortcut)
  File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 355, in __init__
    info = get_ppa_info(self.shortcut)
  File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 338, in get_ppa_info
    _get_suggested_ppa_message(user, ppa))
  File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 295, in _get_suggested_ppa_message
    lp_user = get_info_from_lp(LAUNCHPAD_USER_API % user)
  File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 87, in get_info_from_lp
    return _get_https_content_py3(lp_url)
  File "/usr/lib/python3/dist-packages/softwareproperties/ppa.py", line 101, in _get_https_content_py3
    lp_page = urllib.request.urlopen(request, cafile=LAUNCHPAD_PPA_CERT)
  File "/usr/lib/python3.4/urllib/request.py", line 148, in urlopen
    raise ValueError('SSL support not available')
ValueError: SSL support not available

Answer 1

可能与此情况相同，SSL 支持不可用，Ubuntu 18.04，ppa 存储库

系统中安装了 openssl 的自定义/不兼容版本。

• 检查当前二进制文件

  which openssl
  

• 检查是否有 PPA 的副本或者它是绝对的

  aptitude search '?narrow(?installed, ~Oppa | ~o)'
  

• 检查是否使用安装了任何库pip

  pip2 show pyOpenSSL