OsNotDetected exception when running rosdep update

[lucascoelhof]

I am running Pop!_OS version 20.04 and ROS2 Foxy. When running rosdep update I get:

reading in sources list data from /etc/ros/rosdep/sources.list.d
Hit https://raw.githubusercontent.com/ros/rosdistro/master/rosdep/osx-homebrew.yaml
Hit https://raw.githubusercontent.com/ros/rosdistro/master/rosdep/base.yaml
Hit https://raw.githubusercontent.com/ros/rosdistro/master/rosdep/python.yaml
Hit https://raw.githubusercontent.com/ros/rosdistro/master/rosdep/ruby.yaml
Hit https://raw.githubusercontent.com/ros/rosdistro/master/releases/fuerte.yaml
Query rosdistro index https://raw.githubusercontent.com/ros/rosdistro/master/index-v4.yaml
Skip end-of-life distro "ardent"
Skip end-of-life distro "bouncy"
Skip end-of-life distro "crystal"
Add distro "dashing"

ERROR: Rosdep experienced an error: Could not detect OS, tried ['zorin', 'windows', 'nixos', 'clearlinux', 'ubuntu', 'slackware', 'rhel', 'qnx', 'osx', 'sailfishos', 'tizen', 'opensuse', 'opensuse', 'opensuse', 'opensuse', 'openembedded', 'neon', 'mx', 'mint', 'linaro', 'gentoo', 'funtoo', 'freebsd', 'fedora', 'elementary', 'elementary', 'debian', 'cygwin', 'centos', 'manjaro', 'arch', 'alpine']
Please go to the rosdep page [1] and file a bug report with the stack trace below.
[1] : http://www.ros.org/wiki/rosdep

rosdep version: 0.19.0

Traceback (most recent call last):
  File "/usr/lib/python3/dist-packages/rosdep2/main.py", line 144, in rosdep_main
    exit_code = _rosdep_main(args)
  File "/usr/lib/python3/dist-packages/rosdep2/main.py", line 428, in _rosdep_main
    return _no_args_handler(command, parser, options, args)
  File "/usr/lib/python3/dist-packages/rosdep2/main.py", line 437, in _no_args_handler
    return command_handlers[command](options)
  File "/usr/lib/python3/dist-packages/rosdep2/main.py", line 646, in command_update
    update_sources_list(success_handler=update_success_handler,
  File "/usr/lib/python3/dist-packages/rosdep2/sources_list.py", line 507, in update_sources_list
    rosdep_data = get_gbprepo_as_rosdep_data(dist_name)
  File "/usr/lib/python3/dist-packages/rosdep2/gbpdistro_support.py", line 150, in get_gbprepo_as_rosdep_data
    ctx = create_default_installer_context()
  File "/usr/lib/python3/dist-packages/rosdep2/__init__.py", line 90, in create_default_installer_context
    m.register_platforms(context)
  File "/usr/lib/python3/dist-packages/rosdep2/platforms/debian.py", line 55, in register_platforms
    register_elementary(context)
  File "/usr/lib/python3/dist-packages/rosdep2/platforms/debian.py", line 82, in register_elementary
    (os_name, os_version) = context.get_os_name_and_version()
  File "/usr/lib/python3/dist-packages/rosdep2/installers.py", line 115, in get_os_name_and_version
    os_name = self.os_detect.get_name()
  File "/usr/lib/python3/dist-packages/rospkg/os_detect.py", line 698, in get_name
    self.detect_os()
  File "/usr/lib/python3/dist-packages/rospkg/os_detect.py", line 668, in detect_os
    raise OsNotDetected("Could not detect OS, tried %s" % attempted)
rospkg.os_detect.OsNotDetected: Could not detect OS, tried ['zorin', 'windows', 'nixos', 'clearlinux', 'ubuntu', 'slackware', 'rhel', 'qnx', 'osx', 'sailfishos', 'tizen', 'opensuse', 'opensuse', 'opensuse', 'opensuse', 'openembedded', 'neon', 'mx', 'mint', 'linaro', 'gentoo', 'funtoo', 'freebsd', 'fedora', 'elementary', 'elementary', 'debian', 'cygwin', 'centos', 'manjaro', 'arch', 'alpine']

I also tried setting ROS_OS_OVERRIDE environment variable and it did not work.

[christophebedard]

What version of rospkg do you have? You can run pip3 show rospkg to check. It has to be >=1.2.7 for Pop!_OS support (#199).

[lucascoelhof]

I was using 1.2.6. I upgraded rospkg using the following command:

sudo pip3 install rospkg --upgrade

Then I ran rosdep update again and it worked.
Thank you very much for the help!