Dockerfile

ARG BASE=ghcr.io/r-wasm/flang-wasm:main
FROM $BASE AS webr

# Setup environment for Emscripten
ENV PATH="/opt/emsdk:/opt/emsdk/upstream/emscripten:${PATH}"
ENV EMSDK="/opt/emsdk"
ENV WEBR_ROOT="/opt/webr"
ENV EM_NODE_JS="/usr/bin/node"
ENV EMFC="/opt/flang/host/bin/flang-new"

# Step 1: Build fake Rust DEB packages
# 
# Installing this makes sure the toolchain installed in the later step is used
# instead of the one that the distro (Ubuntu) provides.
FROM webr AS deb_build
RUN mkdir /opt/fake_rust/ && \
    apt-get update && \
    apt-get install -y equivs lsb-release &&\
    equivs-control fake_rust && \
    sed -i 's/Package:.*/Package: rustc/' fake_rust && \
    sed -i 's/# Version:.*/Version: 99.0/' fake_rust && \
    equivs-build fake_rust && \
    sed -i 's/Package:.*/Package: cargo/' fake_rust && \
    equivs-build fake_rust && \
    mv rustc_99.0_all.deb cargo_99.0_all.deb /opt/fake_rust/

# Step 2: Do the necessary setups
FROM webr AS webr_scratch
# Install nodejs
RUN apt-get update && \
    apt-get install nodejs npm -y

# Install Rust; these lines are based on the official Rust docker image:
# https://github.com/rust-lang/docker-rust/blob/master/Dockerfile-debian.template
ENV PATH="/usr/local/cargo/bin:${PATH}"
ENV RUSTUP_HOME=/usr/local/rustup
ENV CARGO_HOME=/usr/local/cargo
RUN set -eux; \
    wget "https://static.rust-lang.org/rustup/archive/1.26.0/x86_64-unknown-linux-gnu/rustup-init"; \
    echo "0b2f6c8f85a3d02fde2efc0ced4657869d73fccfce59defb4e8d29233116e6db *rustup-init" | sha256sum -c -; \
    chmod +x rustup-init; \
    ./rustup-init -y \
    --no-modify-path \
    --profile minimal \
    --default-toolchain nightly \
    --default-host x86_64-unknown-linux-gnu \
    --target wasm32-unknown-emscripten \
    --component rust-src; \
    rm rustup-init; \
    chmod -R a+w $RUSTUP_HOME $CARGO_HOME; \
    rustup --version; \
    cargo --version; \
    rustc --version;

# Install the fake Rust DEB packages. 
COPY --from=deb_build /opt/fake_rust /tmp/fake_rust
RUN dpkg -i /tmp/fake_rust/rustc_99.0_all.deb && \
    dpkg -i /tmp/fake_rust/cargo_99.0_all.deb && \
    rm -rf /tmp/fake_rust

# Install rig
RUN curl -L https://rig.r-pkg.org/deb/rig.gpg -o /etc/apt/trusted.gpg.d/rig.gpg && \
    echo "deb http://rig.r-pkg.org/deb rig main" > /etc/apt/sources.list.d/rig.list && \
    apt-get update && \
    apt-get install r-rig -y

# Because $HOME gets masked by GHA with the host $HOME
ENV R_LIBS_USER=/opt/R/current/lib/R/site-library
# Don't install pak. Rig installs it into the user lib, but we want it in the system lib
RUN rig add 4.4.2 --without-pak
# Install pak and rwasm into the system lib
RUN /opt/R/current/bin/R -q -e 'install.packages("pak", lib = .Library)'
RUN /opt/R/current/bin/R -q -e 'pak::pak("r-wasm/rwasm", lib = .Library)'

# Download webR and configure for LLVM flang
ARG WEBRCI_REPO="https://github.com/r-wasm/webr.git"
RUN git clone ${WEBRCI_REPO} /opt/webr
WORKDIR /opt/webr
ARG WEBRCI_SHA=HEAD
RUN git checkout ${WEBRCI_SHA}
RUN ./configure

# Install r-wasm's webr package for native R
RUN R CMD INSTALL packages/webr

# Build webR with supporting Wasm libs
ARG MAKE_LIBS_TARGET="all"
RUN cd libs && make ${MAKE_LIBS_TARGET}
RUN make

# Cleanup
RUN apt-get clean && rm -rf /var/lib/apt/lists/*
RUN rm -rf /tmp/rig
RUN rm -rf libs/download libs/build src/node_modules R/download
RUN cd src && make clean

# Temp workaround for https://github.com/emscripten-core/emscripten/issues/22571
RUN sed -i.bak 's|#define TYPEOF|#define FT_TYPEOF|g' /opt/emsdk/upstream/emscripten/cache/sysroot/include/freetype2/config/ftconfig.h

# Step 3: Squash docker image layers
FROM webr
COPY --from=webr_scratch / /
ENV PATH="/usr/local/cargo/bin:${PATH}"
ENV RUSTUP_HOME=/usr/local/rustup
ENV CARGO_HOME=/usr/local/cargo
WORKDIR /root
SHELL ["/bin/bash", "-c"]