Error parsing YAML: found unexpected ':'

[KnechtNoobrecht]

I am trying to build a container to run ROS2 Foxy on my Jetson Nano with Jetpack 4.6.4. So i downloaded the repo, installed all pip dependencies, set the docker default runtime to nvidia and verified that setting. Now when i try to run ./build.sh --list-packages i get the following error:

Namespace(base='', build_flags='', list_packages=False, logs='', multiple=False, name='', no_github_api=False, package_dirs=[''], packages=['ros:foxy-ros-base'], push='', show_packages=False, simulate=False, skip_errors=False, skip_packages=[''], skip_tests=[''], test_only=[''], verbose=False)
-- L4T_VERSION=32.7.4
-- JETPACK_VERSION=4.6.4
-- CUDA_VERSION=10.2.300
-- LSB_RELEASE=18.04 (bionic)
-- Error parsing YAML from /home/jetson/jetson-containers/packages/tensorflow/Dockerfile:  while scanning a plain scalar
  in "<unicode string>", line 3, column 50:
     ... cudnn, tensorrt, python, numpy, protobuf:cpp]
                                         ^
found unexpected ':'
  in "<unicode string>", line 3, column 58:
     ... ensorrt, python, numpy, protobuf:cpp]
                                         ^
Please check http://pyyaml.org/wiki/YAMLColonInFlowContext for details.

[dusty-nv]

Hi @KnechtNoobrecht, this is strange, I just ran the same command without error on JetPack 4.6.

What does pip3 show pyyaml report for you?

pip3 show pyyaml
Name: PyYAML
Version: 6.0.1
Summary: YAML parser and emitter for Python
Home-page: https://pyyaml.org/
Author: Kirill Simonov
Author-email: xi@resolvent.net
License: MIT
Location: /home/nvidia/.local/lib/python3.6/site-packages
Requires:

[KnechtNoobrecht]

Thanks for your answer, @dusty-nv. pip3 show pyyaml reports the following:

Name: PyYAML
Version: 3.12
Summary: YAML parser and emitter for Python
Home-page: http://pyyaml.org/wiki/PyYAML
Author: Kirill Simonov
Author-email: xi@resolvent.net
License: MIT
Location: /usr/lib/python3/dist-packages
Requires: 
Required-by: rosdep, rosdep-modules, rosinstall-generator, rospkg, rospkg-modules

I see a huge version difference, but the latest version available in the bionic apt repositories is 3.12. Edit: The Python3 version i am using is 3.6.9.

[dusty-nv]

Interesting... during the pip3 install -r requirements command from the System Setup, it should have installed a similar version of PyYAML to mine on your system. Can you run that, or pip3 install --upgrade pyyaml ?

[KnechtNoobrecht]

Running pip3 install -r requirements.txt results in following output: Requirement already satisfied: pyyaml in /usr/lib/python3/dist-packages (from -r requirements.txt (line 2)) (3.12) But pip3 install --upgrade pyyaml upgraded the version to 6.0.1. Maybe that's something one could update in the requirements.txt, to specifically demand version 6.0.1. Thanks for your help!

[dusty-nv]

Thanks yes @KnechtNoobrecht, that must be how this error occurred for you - I will update requirements.txt to install pyyaml>6