I am using elixir 1.9 with erlang 22.0 and I am using the command mix release. However when I try to run my app with _build/dev/rel/andy/bin/my_app start start I get an error:
Error
This is the error I get when trying to run it:
/home/devops/_build/dev/rel/my_app/erts-10.4.3/bin/beam.smp: error while loading shared libraries: libtinfo.so.6: cannot open shared object file: No such file or directory
To fix it I tried running sudo apt-get install libtinfo.so.6 but it doesn’t look like it exists:
Reading package lists... Done
Building dependency tree
Reading state information... Done
E: Unable to locate package libtinfo.so.6
E: Couldn't find any package by glob 'libtinfo.so.6'
E: Couldn't find any package by regex 'libtinfo.so.6'
This is my OS operation:
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 16.04.6 LTS
Release: 16.04
Codename: xenial
I have the same error when trying to run an app that I built in Docker on the Elixir 1.9.1 image, my Dockerfile is:
FROM elixir:1.9.1 AS builder
WORKDIR /app/monolith
COPY . .
ENV MIX_ENV=prod
WORKDIR /app/monolith/apps/server
RUN mix local.hex --force; mix local.rebar --force
RUN mix deps.get
RUN mix compile
FROM builder AS release
WORKDIR /app/monolith/apps/server
ENV MIX_ENV=prod
RUN mix release
ENTRYPOINT ["/app/monolith/_build/prod/rel/server/bin/server"]
Yeah, _build and deps from your host should never slip into the container, or vice versa…
Also there are some other culprits with your dockerfile. Even the final stage still contains all the temporary artifacts and source code. This increases the size of the resulting image unnecessarily. You should try to properly use the multi-stage you already started with.
Yup, thank you. I got it working with the following Dockerfile:
FROM elixir:1.9.1 AS builder
WORKDIR /app/monolith
COPY . .
WORKDIR /app/
ENV MIX_ENV=dev
WORKDIR /app/monolith/apps/server
RUN mix local.hex --force; mix local.rebar --force
RUN mix deps.get
RUN mix compile
FROM builder AS release
WORKDIR /app/monolith/apps/server
ENV MIX_ENV=dev
RUN mix release
ENTRYPOINT ["/app/monolith/_build/dev/rel/server/bin/server"]
FROM base AS runner
COPY --from=release /app/monolith/_build/dev/rel/server/ /app
ENTRYPOINT [ "/app/bin/server" ]
and .dockerignore:
.git
_build
Still needs a bit of work, in particular to allow prod builds, but its a start.
(I take your point about not copying in the deps, but that is giving me issues with a timeout from hex.pm when fetching tzdata.)
Just as addition here: I got this error because the build was running on Ubuntu 18.10 but my prod is running on Ubuntu 18.04. So I migrated my pipeline back to 18.04 and everything is fine again
Just for the record, I came across this yesterday, same issue, etc. and this is the final working Dockerfile I came up with, in case anybody finds it useful.
FROM elixir:1.10.3 AS app_builder
ENV MIX_ENV=prod \
LANG=C.UTF-8
# Build local package repository
RUN mix local.hex --force && \
mix local.rebar --force
RUN mkdir /app
WORKDIR /app
# Compile dependencies
COPY mix.exs .
COPY mix.lock .
RUN mix deps.get && mix deps.compile
# Let's make sure we have node
RUN curl -sL https://deb.nodesource.com/setup_14.x | bash - && \
apt-get install -y nodejs
# Compile assets
COPY assets ./assets
RUN npm install --prefix ./assets && \
npm run deploy --prefix ./assets
# Now, let's go with the actual elixir code. The order matters: if we only
# change elixir code, all the above layers will be cached ~ less image build time.
COPY config ./config
COPY lib ./lib
COPY priv ./priv
# Final build step: digest static assets and generate the release
RUN mix phx.digest && mix release
FROM debian:buster-slim AS app
ENV LANG=C.UTF-8
RUN apt-get update && apt-get install -y openssl
RUN useradd --create-home app
WORKDIR /home/app
COPY --from=app_builder /app/_build .
RUN chown -R app: ./prod
USER app
CMD ["./prod/rel/cookbook/bin/cookbook", "start"]
