Can Cargo download and build dependencies without also building the application?

Question

Is there a way to tell Cargo to install and build all my dependencies, but not attempt to build my application?

I thought cargo install would do that, b

Answer 1

Based on a GitHub comment

FROM rust:1.37

WORKDIR /usr/src

# Create blank project
RUN USER=root cargo new PROJ

# We want dependencies cached, so copy those first.
COPY Cargo.toml /usr/src/PROJ/
COPY Cargo.lock /usr/src/PROJ/

WORKDIR /usr/src/PROJ

# This is a dummy build to get the dependencies cached.
RUN cargo build --release

# Now copy in the rest of the sources
COPY MyPROJECT/src /usr/src/PROJ/src/

# This is the actual build.
RUN cargo build --release \
    && mv target/release/appname /bin \
    && rm -rf /usr/src/PROJ

WORKDIR /

EXPOSE 8888

CMD ["/bin/appname"]