Upgrade buildkit version and support heredocs syntax

[roi-orca]

Support heredocs syntax and add them to the command output to consume it.
Currently instructions with heredocs syntax break the parsing (added undefined commands to the output)
https://docs.docker.com/engine/reference/builder/#here-documents
https://www.docker.com/blog/introduction-to-heredocs-in-dockerfiles/
Thanks!

[roi-orca]

@asottile

[asottile]

@roi-orca

[duaraghav8]

@asottile @roi-orca
Hey guys. Thanks for this project, really helpful!

I just ran into this issue myself.
Any plans on resolving this soon? I see an open PR to upgrade buildkit version, so wanted to check if if you're going to be merging soon.

ATM, this ends up parsing the shell commands inside as separate Commands

>>> print(run)
RUN <<EOF
source $HOME/.bashrc && echo $HOME
EOF

>>> t = dockerfile.parse_string(run)

>>> t
(Command(cmd='RUN', sub_cmd=None, json=False, original='RUN <<EOF', start_line=1, end_line=1, flags=(), value=('<<EOF',)), Command(cmd='source', sub_cmd=None, json=False, original='source $HOME/.bashrc && echo $HOME', start_line=2, end_line=2, flags=(), value=('',)), Command(cmd='EOF', sub_cmd=None, json=False, original='EOF', start_line=3, end_line=3, flags=(), value=('',)))

Thanks

[asottile]

I don't have any plans -- the dependabot PR doesn't really mean anything as it was auto generated. if a test is added and the version is bumped then I can review it and release it but I'm not going to bump the version just to bump it unless there's a demonstrated reason to do so

[sebastian-echeverria]

@asottile I tried to address this issue by updating buildkit, adding some needed functionality to properly parse heredocs, and adding tests for this in PR #202

[asottile]

archiving the project: closing this out