DockerFile

# The process is really cool. This is a multi-stage docker image. 
# First we use the rust-musl-builder to build our application. 
# When this is done, we can 



FROM ekidd/rust-musl-builder:stable as builder


# Create a new cargo crate with grpc-test for initialization reasons only
RUN USER=root cargo new --bin grpc-test
WORKDIR ./grpc-test

# Add all the files from host machine to container. Please note that .dockerignore is used not to copy unnecessary stuff.
ADD . ./

RUN cargo build --release


# Remove all source code files. 
# Remove folders in the release directory that are not needed.
RUN rm src/*.rs \
    && rm -r ./target/x86_64-unknown-linux-musl/release/build \
    && rm -r ./target/x86_64-unknown-linux-musl/release/examples \
    && rm -r ./target/x86_64-unknown-linux-musl/release/deps \
    && rm -r ./target/x86_64-unknown-linux-musl/release/incremental \
    && rm -r ./target/x86_64-unknown-linux-musl/release/*.d \
    #&& rm -r ./target/x86_64-unknown-linux-musl/release/*.rlib \
    && echo "gRPC-Test Image has been built in the 'builder' image."

# Use Alpine linux
FROM alpine:latest

# App will run from this location
ARG APP=/usr/src/app

# These are the ports exposed for use.
ARG SERVERPORT
#EXPOSE $SERVERPORT 50051
EXPOSE 50051

# Set timezone, and permissions for users.
ENV TZ=Etc/UTC \
    APP_USER=appuser

RUN addgroup -S $APP_USER \
    && adduser -S -g $APP_USER $APP_USER

# Add ca-certificate and bash - comes in handy.
RUN apk update \
    && apk add --no-cache ca-certificates tzdata \
    && rm -rf /var/cache/apk/* \
    && apk add --no-cache bash

# Copy the built code to the app folder
# Note that we're getting this from the builder container here!
# Please note that here we're adding files manually for a reason: If we copy all the folder and remove stuff  later , 
# the container size will still be huge. Don't try to be clever :)
COPY --from=builder /home/rust/src/grpc-test/target/x86_64-unknown-linux-musl/release/* ${APP}/

# Set permission to user to access app
RUN chown -R $APP_USER:$APP_USER ${APP} \
    && RUST_BACKTRACE="1" \
    && RUST_LOG="debug"


USER $APP_USER
WORKDIR ${APP}

# Run the application. Server by default
CMD server