我们正在防火墙后面尝试运行一个Docker镜像（cBioportal）。2 Docker本身可以安装一个代理，但是现在我们遇到了以下问题：

Starting validation...

INFO: -: Unable to read xml containing cBioPortal version.
DEBUG: -: Requesting cancertypes from portal at 'http://cbioportal-container:8081'
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
Error occurred during validation step:
Traceback (most recent call last):
  File "/cbioportal/core/src/main/scripts/importer/validateData.py", line 4491, in request_from_portal_api
    response.raise_for_status()
  File "/usr/local/lib/python3.5/dist-packages/requests/models.py", line 940, in raise_for_status
    raise HTTPError(http_error_msg, response=self)
requests.exceptions.HTTPError: 504 Server Error: Gateway Timeout for url: http://cbioportal-container:8081/api-legacy/cancertypes

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/usr/local/bin/metaImport.py", line 127, in <module>
    exitcode = validateData.main_validate(args)
  File "/cbioportal/core/src/main/scripts/importer/validateData.py", line 4969, in main_validate
    portal_instance = load_portal_info(server_url, logger)
  File "/cbioportal/core/src/main/scripts/importer/validateData.py", line 4622, in load_portal_info
    parsed_json = request_from_portal_api(path, api_name, logger)
  File "/cbioportal/core/src/main/scripts/importer/validateData.py", line 4495, in request_from_portal_api
    ) from e
ConnectionError: Failed to fetch metadata from the portal at [http://cbioportal-container:8081/api-legacy/cancertypes]

现在我们知道这是一个防火墙的问题，因为当我们把它安装在防火墙之外时，它就可以工作了。但是我们还不知道如何改变防火墙。我们的想法是查找引发错误的文件和行。但是我们不知道如何查看文件，因为它们在Docker中。
因此，我们不能只做一些像vim /cbioportal/core/src/main/scripts/importer/ www.example.com这样的事情validateData.py
......因为......什么都没有。当然，我们知道这个文件在Docker镜像中，但是就像我说的，我们不知道如何去查看它。目前我们不知道如何解开这个谜--任何帮助都是感激的。