rosdep update 指令超时问题

在执行rosdep update后出现超时问题，报如下错误
reading in sources list data from /etc/ros/rosdep/sources.list.d ERROR: unable to process source [https://raw.githubusercontent.com/ros/rosdistro/master/rosdep/osx-homebrew.yaml]: <urlopen error timed out> (https://raw.githubusercontent.com/ros/rosdistro/master/rosdep/osx-homebrew.yaml) Hit https://raw.githubusercontent.com/ros/rosdistro/master/rosdep/base.yaml
首先执行

sudo gedit /usr/lib/python2.7/dist-packages/rosdep2/sources_list.py

然后找到download_rosdep_data函数，大概在300行左右加上这句话url="https://ghproxy.com/"+url，改完之后是这样

def download_rosdep_data(url):
    """
    :raises: :exc:`DownloadFailure` If data cannot be
        retrieved (e.g. 404, bad YAML format, server down).
    """
    try:
        # http/https URLs need custom requests to specify the user-agent, since some repositories reject
        # requests from the default user-agent.
	url="https://ghproxy.com/"+url
        if url.startswith("http://") or url.startswith("https://"):
            url_request = request.Request(url, headers={'User-Agent': 'rosdep/{version}'.format(version=__version__)})
        else:
            url_request = url
        f = urlopen(url_request, timeout=DOWNLOAD_TIMEOUT)
        text = f.read()
        f.close()
        data = yaml.safe_load(text)
        if type(data) != dict:

然后执行

sudo gedit /usr/lib/python2.7/dist-packages/rosdistro/__init__.py

将DEFAULT_INDEX_URL进行更改
改为DEFAULT_INDEX_URL = 'https://ghproxy.com/https://raw.githubusercontent.com/ros/rosdistro/master/index-v4.yaml'