Krew install fails on Ubuntu WSL (Windows Subsystem for Linux)

[StianOvrevage]

# (
>   set -x; cd "$(mktemp -d)" &&
>   curl -fsSLO "https://storage.googleapis.com/krew/v0.2.1/krew.{tar.gz,yaml}" &&
>   tar zxvf krew.tar.gz &&
>   ./krew-"$(uname | tr '[:upper:]' '[:lower:]')_amd64" install \
>     --manifest=krew.yaml --archive=krew.tar.gz
> )
++ mktemp -d
+ cd /tmp/tmp.y04kz5whCK
+ curl -fsSLO 'https://storage.googleapis.com/krew/v0.2.1/krew.{tar.gz,yaml}'
+ tar zxvf krew.tar.gz
./krew-darwin_amd64
./krew-linux_amd64
./krew-linux_arm
./krew-windows_amd64.exe
++ uname
++ tr '[:upper:]' '[:lower:]'
+ ./krew-linux_amd64 install --manifest=krew.yaml --archive=krew.tar.gz
Installing plugin: krew
W0311 13:32:17.764882     418 install.go:132] failed to install plugin "krew": failed to dowload and move during installation: could not rename file from "/tmp/krew-temp-move308169657" to "/root/.krew/store/krew/dc2f2e1ec8a0acb6f3e23580d4a8b38c44823e948c40342e13ff6e8e12edb15a": rename /tmp/krew-temp-move308169657 /root/.krew/store/krew/dc2f2e1ec8a0acb6f3e23580d4a8b38c44823e948c40342e13ff6e8e12edb15a: permission denied
F0311 13:32:17.768004     418 root.go:52] failed to install some plugins: [krew]

Tried as root and non-root. Both fails with same error.

[ahmetb]

See #156.

[StianOvrevage]

I reviewed that ticket before opening and I do not think they are the same.

[HoveringHalibut]

@StianOvrevage The issue is with the length of the underlying NTFS path of the WSL root directory, whose mount defaults to deep in your windows profile. With the additional krew folder depth and long length of the folder name, the full path exceeds the Windows MAX_PATH length of 260.

I worked around the issue by moving my /home mount to a directory in the root of C:

This is using the WSL Ubuntu image:

/etc/fstab
LABEL=cloudimg-rootfs / ext4 defaults 0 0
C: /mnt/c drvfs rw,noatime,uid=1000,gid=1000,umask=22,fmask=11 0 0
/mnt/c/linuxhome /home drvfs bind 0 0

/etc/wsl.conf
[automount]
mountFsTab = true

[ahmetb]

@StianOvrevage can you give an example of a full path exceeding MAX_PATH? I'm curious how it looks like witht he additional krew folder depth.

[StianOvrevage]

Great job figuring this out!

I was not able to get automatic mounting of /home to work. There was no wsl.conf so maybe there are some differences between our setups.

I did however just mount /mnt/c/linuxhome temporarily for the install and then moved krew into /krew. Hopefully this works without breaking too many of krews expectations about how things should look.

[ahmetb]

If any of you could write up summary a summary of the WSL issue, I would like to link to it from the README>Installation section as a "Known issue with WSL".

[StianOvrevage]

@ahmetb I don't know enough about WSL to actually find the underlying path as mapped to the NTFS disk.

According to https://blogs.msdn.microsoft.com/wsl/2016/06/15/wsl-file-system-support/ at some point it was at %LocalAppData%\lxss\rootfs but I do not have that folder on my machine. That path would translate to C:\Users\Stian\AppData\Local\lxss\rootfs here.

[ahmetb]

echo 'C:\Users\Stian\AppData\Local\lxss\rootfs\home/MYUSERNAME/.krew/store01ba4719c80b6fe911b091a7c05124b64eeece964e09c058ef8f9805daca546b/store/plugin-name/kubectl-plugin-name' | wc -c is around ~170 chars, not sure if it could easily reach 260 chars as long as your user name is very long.

[HoveringHalibut]

@StianOvrevage wsl.conf doesn't exist by default, you can just create it.

@ahmetb The full patch for me is only 214, now that I actually counted.
C:\Users\halibuthh\AppData\Local\Packages\CanonicalGroupLimited.UbuntuonWindows_79rhkp1fndgsc\LocalState\rootfs\home\halibuthh\.krew\store\krew\dc2f2e1ec8a0acb6f3e23580d4a8b38c44823e948c40342e13ff6e8e12edb15a\krew

What's odd is that it is a permission error and I traced all the system calls and they looked fine from a user permissions stand-point. It could just be a bad error message.

It was a bit for naught anyway, pending this fix for kubectl executing plugins in WSL:
kubernetes/kubernetes#76227

[alioSHA512]

This Worked for me,
#159 (comment)

But I don't want to move my /home directory, so I created dir /mnt/c/krew and linked it to ~/.krew, and that did the trick.

$ ln -s /mnt/c/krew/ ~/.krew

[ahmetb]

@alioSHA512 Good to hear. You can also set KREW_ROOT environment variable to point to any directory you want to use.