Building the container behind a proxy

[javixeneize]

Hi

One interesting question... How to build a container behind a proxy?

When running pip to install the dependencies, it cant resolve the host, so you need to add a proxy in the docker file

While using a ubuntu image, exporting the proxy is easy (ENV http_proxy .....), using alpine or python templates doesnt work

Any idea on how to solve this problem?

[jfloff]

Nice question. A quick google search gave me these discussions at the official Alpine docker image:

• apk update/add in the docker container under proxy giving permission denied gliderlabs/docker-alpine#191 (comment)
• Running apk commands behind proxy fails gliderlabs/docker-alpine#171

Do you think you could test this approach with a custom Dockerfile and provide feedback?

[jfloff]

Were you able to reach a solution @javixeneize ?

[javixeneize]

Hi. Sorry, yes, it works fine configuring the proxy inside

Thanks

[jfloff]

Could you give some details on how you made it? Maybe write those instructions in the README and PR?

[javixeneize]

Hi It was really straightforward. Just add a line to the docker file to configure the proxy :) FROM alpine:3.3 ENV http_proxy http://proxy.com ENV https_proxy http://proxy.com ...... Thanks

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On Tue, Apr 25, 2017 at 12:46 PM, João Ferreira Loff < ***@***.***> wrote: Could you give some details on how you made it? Maybe write those instructions in the README and PR? — You are receiving this because you modified the open/close state. Reply to this email directly, view it on GitHub <#10 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AMK55nDhkR9vj13cJ2rCVQfOhBEjWEpqks5rzd0XgaJpZM4MuBwx> .

[gbarco]

I would like to reopen threads like this one but requiring an answer that allows another person to run the same image without modifying and rebuilding from Dockerfile.

ENV in Dockerfile is so local, hacky and non portable it cripples Docker to uselessness in corporations.
Also incomplete since I assume you also will need a proxy to get your base image.

I expect proxy on host talks or something level of conversation to reach a solution.

[jfloff]

I actually stumped on this the other day: use ARG during the build. More details here: https://docs.docker.com/engine/reference/commandline/build/#set-build-time-variables-build-arg

Taken from the link above: $ docker build --build-arg HTTP_PROXY=http://10.20.30.2:1234 .

I think this fits your scenario.

[Multihuntr]

I would like to second using the --build-arg flag instead of ENV in the Dockerfile. By setting the --build-arg correctly, you set the environment variable only for build time.
By setting the environment variables within the Dockerfile, you are saying that it will always have to use those proxy settings (it's not so easy to unset an environment variable in docker), even in a running container, or any derivative images.
I got caught by this one yesterday.