add dockerfile and .dockerignore

- This lets you build sms-irc and get a nice Docker container out of it.
- However, the generated container still requires _alot_ of manual
  setup, and you'll need to mount a volume to give it some config.

.dockerignore

@@ -0,0 +1,7 @@
+Dockerfile
+.git*
+**/target*
+**/*.rs.bk
+**/config.toml
+**/Rocket.toml
+**/*.swp

Dockerfile

@@ -0,0 +1,40 @@
+FROM archlinux/base:latest AS sms-irc-compiled
+
+# update OS
+RUN pacman -Syu --noconfirm
+RUN pacman -S --needed --noconfirm base-devel
+
+# install Rust: download rustup
+RUN curl https://sh.rustup.rs -sSf | sh -s -- --default-toolchain stable -y
+
+# The following bits build just the dependencies of the project, without the source-code itself.
+# This is so that we can take advantage of docker's caching and not rebuild everything all the damn time :P
+
+WORKDIR /sms-irc
+# add all the cargo files, to get deps
+ADD ./Cargo.lock /sms-irc/
+ADD ./Cargo.toml /sms-irc/
+# make dummy src/lib.rs files, to satisfy cargo
+RUN /bin/bash -c 'mkdir src; touch src/lib.rs';
+# disable incremental compilation (never going to be used, and bloats binaries)
+ENV CARGO_INCREMENTAL=0
+# build all the dependencies
+RUN ~/.cargo/bin/cargo build --release
+# remove the dummy src/ lib.rs files
+RUN /bin/bash -c 'rm -rf src'
+
+# Now we a build the actual code...
+
+# add the actual code
+ADD ./src /sms-irc/src
+# add some dependencies
+RUN pacman -S --noconfirm postgresql-libs
+# build it!
+RUN ~/.cargo/bin/cargo build --release
+
+FROM debian:stable-slim AS sms-irc
+WORKDIR /sms-irc
+RUN apt-get update && apt-get install -y libssl1.1 ca-certificates libpq5
+RUN apt-get clean && rm -rf /var/lib/apt/lists/*
+COPY --from=sms-irc-compiled /sms-irc/target/release/sms-irc /sms-irc
+ENTRYPOINT "/sms-irc/sms-irc"