Windows reproducible builds using Docker

.dockerignore

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+*
+!gui/Cargo.*
+!contrib/docker/cargo_config.toml

contrib/docker/Dockerfile

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+FROM debian:bullseye
+
+WORKDIR /liana
+
+# We try to pin our dependencies to avoid potential sources of non-determinism, but we don't go
+# out of our way to pin the whole tree of deps. Instead invest time in getting Guix cross-compilation.
+RUN apt update && apt install -y \
+                    gcc-mingw-w64-x86-64=10.2.1-6+24.2 \
+                    curl=7.74.0-1.3+deb11u3 \
+                    gcc=4:10.2.1-1
+
+# Download the cargo binary and compiled stdlib from the distributed releases to make sure to build with
+# the very same toolchain. We use 1.65.0 because it is unfortunately the MSRV of the GUI.
+RUN curl -O "https://static.rust-lang.org/dist/rust-1.65.0-x86_64-unknown-linux-gnu.tar.gz" && \
+    echo "8f754fdd5af783fe9020978c64e414cb45f3ad0a6f44d045219bbf2210ca3cb9 rust-1.65.0-x86_64-unknown-linux-gnu.tar.gz" | sha256sum -c && \
+    tar -xzf rust-1.65.0-x86_64-unknown-linux-gnu.tar.gz && \
+    curl -O "https://static.rust-lang.org/dist/rust-1.65.0-x86_64-pc-windows-gnu.tar.gz" && \
+    echo "eaa0d89511739c16d2a6149ed3538ce10596c523c4791b4a378dde762cda77e4 rust-1.65.0-x86_64-pc-windows-gnu.tar.gz" | sha256sum -c  && \
+    tar -xzf rust-1.65.0-x86_64-pc-windows-gnu.tar.gz && \
+    rm -r *.tar.gz
+
+# Copy the Cargo files to vendor the dependencies.
+COPY gui/Cargo.toml gui/Cargo.lock /liana/
+
+# We cache the dependencies sources in the image to avoid re-indexing everything from scratch
+# at every run. It was useful when debugging the build, it could be removed eventually if we
+# think the tradeoff vs the image size wasn't worth it anymore.
+RUN /liana/rust-1.65.0-x86_64-unknown-linux-gnu/cargo/bin/cargo vendor
+
+# Cargo configuration for using the vendored dependencies during the build.
+COPY contrib/docker/cargo_config.toml /liana/.cargo/cargo_config.toml
+
+# For some reason, we can't just set the RUSTFLAGS environment variable to add `-L` for compiling dependencies.
+# This doesn't work: RUSTFLAGS="-L /liana/rust-1.65.0-x86_64-pc-windows-gnu/rust-std-x86_64-pc-windows-gnu/lib/rustlib/x86_64-pc-windows-gnu/lib/ -L /liana/rust-1.65.0-x86_64-unknown-linux-gnu/rust-std-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/"
+# As a workaround, we use a wrapped `rustc` binary that always links against the windows stdlib we just downloaded.
+# Some issues that seem to be related:
+# https://github.com/rust-lang/rust/issues/40717
+# https://github.com/rust-lang/rust/issues/48409
+RUN echo "#!/bin/sh" > rustc_wrapper.sh && \
+    echo "/liana/rust-1.65.0-x86_64-unknown-linux-gnu/rustc/bin/rustc \"\$@\" -L /liana/rust-1.65.0-x86_64-pc-windows-gnu/rust-std-x86_64-pc-windows-gnu/lib/rustlib/x86_64-pc-windows-gnu/lib/ -L /liana/rust-1.65.0-x86_64-unknown-linux-gnu/rust-std-x86_64-unknown-linux-gnu/lib/rustlib/x86_64-unknown-linux-gnu/lib/" >> rustc_wrapper.sh && \
+    chmod +x rustc_wrapper.sh && \
+    cat rustc_wrapper.sh && \
+    ./rustc_wrapper.sh -vV
+ENV RUSTC="/liana/rustc_wrapper.sh"
+
+CMD ["./docker/build.sh"]

contrib/docker/build.sh

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+#!/usr/bin/env sh
+
+# =================================================================
+# The script ran within the Docker container to build the Liana GUI.
+# =================================================================
+
+
+# Build the GUI for Windows. The Windows Portable Execution (PE) format contains some timestamps.
+# Instruct ld to set them to 0.
+RUSTFLAGS="-Clink-arg=-Wl,--no-insert-timestamp" /liana/rust-1.65.0-x86_64-unknown-linux-gnu/cargo/bin/cargo rustc --release --target x86_64-pc-windows-gnu
+
+# Avoid having to get root on the host to remove the target dir.
+chmod -R a+rw target/

contrib/docker/cargo_config.toml

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+[source.vendored_sources]
+directory = "vendor"
+
+[source.crates-io]
+replace-with = "vendored_sources"
+
+[source."https://github.com/darosior/rust-miniscript"]
+git = "https://github.com/darosior/rust-miniscript"
+branch = "multipath_descriptors_on_8.0"
+replace-with = "vendored_sources"
+
+[source."https://github.com/revault/liana"]
+git = "https://github.com/revault/liana"
+branch = "master"
+replace-with = "vendored_sources"
+
+# TODO: strip debug symbols as is done in Guix to reduce binary size.

contrib/docker/docker-build.sh

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+#!/usr/bin/env sh
+
+set -ex
+
+TARGET_DIR="$PWD/deter_build_target"
+
+docker build . -t liana_cross_compile -f contrib/docker/Dockerfile
+docker run --rm -ti \
+    -v "$TARGET_DIR":/liana/target \
+    -v "$PWD/contrib/docker":/liana/docker \
+    -v "$PWD/gui/src":/liana/src \
+    -v "$PWD/gui/static":/liana/static \
+    liana_cross_compile
+
+set +ex