Implement Window 10 symlinks

[serge-nikulin]

Implement symlinks via built-in mklink console command that apparently has minimum restrictions.

[serge-nikulin]

Please assign it to me

[dirk-thomas]

Please take a look at the existing but stale PR #6 which already uses the mklink command.

[serge-nikulin]

I see, thanks.
I’ll try nevertheless: it’s too much pain to do development without symlinks.
The fix will require changes in both ament_cmake and ament_tools.
Should I create two separate issues or this singe one will suffice?

[mikaelarguedas]

you can use this single issue to track the feature addition and use Connects to ament/ament_cmake#109 in every PR you open to implement it. That will allow to both cross reference them on github and to connect them together on our waffle board

[dirk-thomas]

The fix will require changes in both ament_cmake and ament_tools.

What do you expect to change in ament_tools? It already sets the CMake variable AMENT_CMAKE_SYMLINK_INSTALL when a symlink install is requested.

[serge-nikulin]

helper.py:

def ament_symlink(source_path, destination_path):
    if os.name == 'nt':
        # Provide Windows 10 compatible symlink
        mklink = "mklink"
        command = [];
        command += ["cmd.exe", "/C", mklink]
        if os.path.isdir(source_path):
             command += ["/D"]
        command += [destination_path.replace('/', '\\')]
        command += [source_path]
        with subprocess.Popen(command, stderr=subprocess.PIPE) as p:
            output = p.stderr.read().decode("utf-8")
            p.wait()
            if output.startswith("Access is denied"):
                raise PermissionError("Permission denied: '%s' -> '%s'" % (source_path, destination_path))
            elif output.startswith("'%s' is not recognized" % mklink):
                raise NotImplementedError()
    else:
        os.symlink(source_path, destination_path)

[dirk-thomas]

That makes sense to also affect the symlinks created by the tool. You should make sure that the logic doesn't rely on a specific locale but works for all users.

[serge-nikulin]

I don't like that / to \ replacement but I don't know any standard way in Python to convert to native path.
CMake has it better with TO_NATIVE_PATH.

[serge-nikulin]

@dirk-thomas,
ament-tools installation with -s switch fails in a curious way (see console log below):

1. No --symlink-install
src\ament\ament_tools\setup.py being executed in src\ament\ament_tools folder and successfully copies completion/ament-completion.* files to install/share/ament_tools/environment folder

2. --symlink-install present
an empty build\ament_tools\completion folder created and ament_tools\setup.py being executed in build\ament_tools folder and fails to copy copies completion/ament-completion.* files because build\ament_tools\completion folder is empty.

I wonder is it intended behavior?

+++ Installing 'ament_tools'
-- [ament] Deploying: C:\Users\serge\Documents\workdir\ros2_ws\install\share\ament_tools\package.xml
-- [ament] Deploying: C:\Users\serge\Documents\workdir\ros2_ws\install\share\ament_tools\environment\ament_prefix_path.bat
-- [ament] Deploying: C:\Users\serge\Documents\workdir\ros2_ws\install\share\ament_tools\environment\path.bat
-- [ament] Deploying: C:\Users\serge\Documents\workdir\ros2_ws\install\share\ament_tools\environment\pythonpath.bat
-- [ament] Deploying: C:\Users\serge\Documents\workdir\ros2_ws\install\share\ament_tools\local_setup.bat
==> 'C:\Users\serge\Documents\workdir\ros2_ws\build\ament_tools\ament_python__install.bat C:\Python\python.exe setup.py develop --prefix C:\Users\serge\Documents\workdir\ros2_ws\install --no-deps install_data --install-dir C:\Users\serge\Documents\workdir\ros2_ws\install' in 'C:\Users\serge\Documents\workdir\ros2_ws\build\ament_tools'
running develop
running egg_info
writing ament_tools.egg-info\PKG-INFO
writing dependency_links to ament_tools.egg-info\dependency_links.txt
writing entry points to ament_tools.egg-info\entry_points.txt
writing requirements to ament_tools.egg-info\requires.txt
writing top-level names to ament_tools.egg-info\top_level.txt
reading manifest file 'ament_tools.egg-info\SOURCES.txt'
writing manifest file 'ament_tools.egg-info\SOURCES.txt'
running build_ext
Creating c:\users\serge\documents\workdir\ros2_ws\install\lib\site-packages\ament-tools.egg-link (link to .)
ament-tools 0.0.0 is already the active version in easy-install.pth
Installing ament-script.py script to C:\Users\serge\Documents\workdir\ros2_ws\install/Scripts
Installing ament.exe script to C:\Users\serge\Documents\workdir\ros2_ws\install/Scripts

Installed c:\users\serge\documents\workdir\ros2_ws\build\ament_tools
running install_data
error: can't copy 'completion\ament-completion.bash': doesn't exist or not a regular file

<== Command 'C:\Users\serge\Documents\workdir\ros2_ws\build\ament_tools\ament_python__install.bat C:\Python\python.exe setup.py develop --prefix C:\Users\serge\Documents\workdir\ros2_ws\install --no-deps install_data --install-dir C:\Users\serge\Documents\workdir\ros2_ws\install' failed in 'C:\Users\serge\Documents\workdir\ros2_ws\build\ament_tools' with exit code '1'

[dirk-thomas]

I wonder is it intended behavior?

Atm we can't use --symlink-install on Windows.

I am not sure if I understand your question but once that option can be used on Windows the intended behavior is obviously not a failure but that is performs the build and install using symlinks rather then copying files (as it already is on Linux and MacOS).

[mikaelarguedas]

@serge-nikulin As we don't see a way to achieve --symlink-install on Windows without requiring admin permissions (a undesired workflow in our opinion) I'm going to close this.
Feel free to comment on the ticket if you have ideas of how to achieve this and we can reopen

[serge-nikulin]

@mikaelarguedas yes, you can close it. I stuck with a Python3 bug (what I perceive as a bug) in Windows specific code. If they fix it I might take another attempt at this one.

[calvertdw]

Sad this isn't working. I am having to run in Administor mode anyway, as suggested by the Windows Development Setup tutorial.

It is probably worth right clicking on the shortcut, selecting properties, then advanced and checking the run as administrator box so that it always opens as administrator. Then you can right click it again and say pin to taskbar so it's easy to get to.

Is it possible to implement this anyway and assume administrator mode?

[serge-nikulin]

@calvertdw , I believe it's a Python's bug. It does not implement a correct symlink command for Windows 10. In the Win10 command line, mklink works fine in user mode.

[calvertdw]

Is there a ticket with them for the issue?