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kelnos/weird.md

Created November 26, 2019 04:39
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Dockerfile COPY is weird
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weird.md

So I do some docker things:

$ ls project
README.md src
$ ls project/src
main test
$ cat Dockerfile
# ... other stuff...
WORKDIR /work
COPY /project/* ./
RUN ls
# ... other stuff
$ docker build .
# ...... stuff
Step 5/50 : COPY /project/* ./
 ---> 212131bcda
Step 6/50 : RUN ls
 ---> Running in deadbeef
README.md main test

Wat. I expect the contents of /work to be README.md and src. Why has docker copied README.md as is, and then sees a directory (src), descends into it, and starts copying from there? That makes no sense. No (reasonable?) shell would behave that way.

The "correct" formulation seems to be COPY /project/. ./, which, ok, that's valid, but... sigh.

@foobarbecue
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foobarbecue commented Feb 5, 2021 •
edited

Yeah docker COPY is bizarre. I dunno what they were thinking. (I googled "docker COPY is weird" looking for some kind of explanation and ended up here)

@feisuzhu
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feisuzhu commented May 6, 2021

Yeah docker COPY is bizarre. I dunno what they were thinking. (I googled "docker COPY is weird" looking for some kind of explanation and ended up here)

Same here

@patsimm
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patsimm commented Jan 10, 2023

Yeah docker COPY is bizarre. I dunno what they were thinking. (I googled "docker COPY is weird" looking for some kind of explanation and ended up here)

Same here

Same here

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