Need to manually copy the docker binary Fedora 29

[greenaussie]

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Need to manually copy the docker binary Fedora 29

Presume due to disk partitioning, use of 'rename' command fails.

$ dvm --debug install 18.03.1-ce
The dvm home directory is: /home/richard/.dvm
dvm install 18.03.1-ce
Installing 18.03.1-ce...
2018/12/30 17:09:37 Checking if 18.03.1-ce can be found at https://download.docker.com/linux/static/stable/x86_64/docker-18.03.1-ce.tgz
2018/12/30 17:09:38 Downloading https://download.docker.com/linux/static/stable/x86_64/docker-18.03.1-ce.tgz
2018/12/30 17:10:29 Could not find a stable release for 18.03.1-ce, checking for a test release
2018/12/30 17:10:29 Checking if 18.03.1-ce can be found at https://download.docker.com/linux/static/test/x86_64/docker-18.03.1-ce.tgz
2018/12/30 17:10:30 Downloading https://download.docker.com/linux/static/test/x86_64/docker-18.03.1-ce.tgz

Attempted to fallback to downloading from the prerelease location after downloading from the stable location failed: Unable to copy /tmp/dvm719964574/docker-18.03.1-ce/docker/docker to /home/richard/.dvm/bin/docker/18.03.1-ce/docker: rename /tmp/dvm719964574/docker-18.03.1-ce/docker/docker /home/richard/.dvm/bin/docker/18.03.1-ce/docker: invalid cross-device link: Unable to copy /tmp/dvm300176997/docker-18.03.1-ce/docker/docker to /home/richard/.dvm/bin/docker/18.03.1-ce/docker: rename /tmp/dvm300176997/docker-18.03.1-ce/docker/docker /home/richard/.dvm/bin/docker/18.03.1-ce/docker: invalid cross-device link
[richard@green hellonode]$ dvm ls
	system (1.13.1)
	18.03.1-ce
->	18.06.1-ce
[richard@green hellonode]$ dvm use 18.03.1-ce
Now using Docker 18.03.1-ce
[richard@green hellonode]$ dvm current
system (1.13.1)
[richard@green hellonode]$ mv /tmp/dvm719964574/docker-18.03.1-ce/docker/* /home/richard/.dvm/bin/docker/18.03.1-ce/
[richard@green hellonode]$ dvm use 18.03.1-ce
Now using Docker 18.03.1-ce
[richard@green hellonode]$ dvm current
18.03.1-ce
[richard@green hellonode]$ 

What should it have done?

Command should have copied the docker binaries.

Helpful Context

Default disk partitioning:

/dev/mapper/fedora-home on /home type ext4 (rw,noatime,seclabel)

What version of dvm are you using?

$ dvm --version
Docker Version Manager version 1.0.1 (b5c28c8)

What is your Operating System?

Fedora 29

What is your shell (bash/powershell/cmd/fish)?

[richard@green hellonode]$ bash --version
GNU bash, version 4.4.23(1)-release (x86_64-redhat-linux-gnu)
Copyright (C) 2016 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>

This is free software; you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
[richard@green hellonode]$ which bash
/usr/bin/bash

How did you install dvm (command-line,chocolatey,homebrew)?

command-line

Do you like kittens? 😸

haha sure.

[carolynvs]

Oops! I think I found the offending line of code:

dvm/dvm-helper/internal/downloader/downloader.go

Line 102 in b5c28c8

err = os.Rename(tmpPath, destPath)

We should either be smarter about detecting when we are crossing partitions, handle that particular error (falling back to a copy) or always use a copy (which is slower) every time.

I'll try to push out a new release for you to try out soon!

[carolynvs]

Alternatively, we could download temp files under the dvm home directory so that its always safe to do a rename. I think that I like that solution the best.