build: Fixes for the Docker building libpq lib.

- Add Postgres dependencies: bison, flex and libiu-dev.
- Fix missing `&&` in chained wget commands.
- Add `POSTGRES_CONFIG` and `PG_CONFIG` for all architectures.
- Remove existing `libpq` Ubuntu packages.
- Copy libpq libraries from builder directly to final image.

Changelog-Fixed: Fixes Postgres driver availability for arm64 and arm32 Docker images.

Dockerfile

@@ -60,15 +60,17 @@ RUN apt-get update -qq && \
     apt-get install -qq -y --no-install-recommends \
         autoconf \
         automake \
+        bison \
         build-essential \
         ca-certificates \
         curl \
         dirmngr \
+        flex \
         gettext \
         git \
         gnupg \
         jq \
-        libpq-dev \
+        libicu-dev \
         libtool \
         libffi-dev \
         pkg-config \
@@ -88,13 +90,14 @@ RUN apt-get update -qq && \
         tclsh
 
 ENV PATH="/root/.local/bin:$PATH"
-ENV PYTHON_VERSION=3
+ENV PYTHON_VERSION=3 \
+    PIP_BREAK_SYSTEM_PACKAGES=1
 RUN curl -sSL https://install.python-poetry.org | python3 -
 RUN update-alternatives --install /usr/bin/python python /usr/bin/python3.9 1
 RUN pip3 install --upgrade pip setuptools wheel
 
 RUN wget -q https://zlib.net/fossils/zlib-1.2.13.tar.gz -O zlib.tar.gz && \
-    wget -q https://www.sqlite.org/2019/sqlite-src-3290000.zip -O sqlite.zip \
+    wget -q https://www.sqlite.org/2019/sqlite-src-3290000.zip -O sqlite.zip && \
     wget -q https://ftp.postgresql.org/pub/source/v17.1/postgresql-17.1.tar.gz -O postgres.tar.gz
 
 WORKDIR /opt/lightningd
@@ -109,6 +112,9 @@ WORKDIR /
 
 FROM base-builder AS base-builder-linux-amd64
 
+ENV POSTGRES_CONFIG="--without-readline" \
+    PG_CONFIG=/usr/local/pgsql/bin/pg_config
+
 FROM base-builder AS base-builder-linux-arm64
 ENV target_host=aarch64-linux-gnu \
     target_host_rust=aarch64-unknown-linux-gnu \
@@ -129,12 +135,13 @@ QEMU_LD_PREFIX=/usr/${target_host} \
 HOST=${target_host} \
 TARGET=${target_host_rust} \
 RUSTUP_INSTALL_OPTS="--target ${target_host_rust} --default-host ${target_host_rust}" \
-PKG_CONFIG_PATH="/usr/${target_host}/lib/pkgconfig" \
-PG_CONFIG_PATH="/usr/${target_host}/bin/pg_config"
+PKG_CONFIG_PATH="/usr/${target_host}/lib/pkgconfig"
 
 ENV \
 ZLIB_CONFIG="--prefix=${QEMU_LD_PREFIX}" \
-SQLITE_CONFIG="--host=${target_host} --prefix=$QEMU_LD_PREFIX"
+SQLITE_CONFIG="--host=${target_host} --prefix=${QEMU_LD_PREFIX}" \
+POSTGRES_CONFIG="--without-readline --prefix=${QEMU_LD_PREFIX}" \
+PG_CONFIG="${QEMU_LD_PREFIX}/bin/pg_config"
 
 FROM base-builder AS base-builder-linux-arm
 
@@ -157,13 +164,13 @@ QEMU_LD_PREFIX=/usr/${target_host} \
 HOST=${target_host} \
 TARGET=${target_host_rust} \
 RUSTUP_INSTALL_OPTS="--target ${target_host_rust} --default-host ${target_host_rust}" \
-PKG_CONFIG_PATH="/usr/${target_host}/lib/pkgconfig" \
-PG_CONFIG_PATH="/usr/${target_host}/bin/pg_config"
+PKG_CONFIG_PATH="/usr/${target_host}/lib/pkgconfig"
 
 ENV \
 ZLIB_CONFIG="--prefix=${QEMU_LD_PREFIX}" \
-SQLITE_CONFIG="--host=${target_host} --prefix=$QEMU_LD_PREFIX" \
-POSTGRES_CONFIG="--without-readline --prefix=${QEMU_LD_PREFIX}"
+SQLITE_CONFIG="--host=${target_host} --prefix=${QEMU_LD_PREFIX}" \
+POSTGRES_CONFIG="--without-readline --prefix=${QEMU_LD_PREFIX}" \
+PG_CONFIG="${QEMU_LD_PREFIX}/bin/pg_config"
 
 FROM base-builder-${TARGETOS}-${TARGETARCH} AS builder
 
@@ -194,7 +201,11 @@ RUN mkdir postgres && tar xvf postgres.tar.gz -C postgres --strip-components=1 \
     && make install \
     && cd ../../../../ && \
     rm postgres.tar.gz && \
-    rm -rf postgres
+    rm -rf postgres && \
+    ldconfig "$(${PG_CONFIG} --libdir)"
+
+# Save libpq to a specific location to copy it into the final image.
+RUN mkdir /var/libpq && cp -a "$(${PG_CONFIG} --libdir)"/libpq.* /var/libpq
 
 ENV RUST_PROFILE=release
 ENV PATH="/root/.cargo/bin:/root/.local/bin:$PATH"
@@ -250,8 +261,8 @@ RUN apt-get update -qq && \
     apt-get clean && \
     rm -rf /var/lib/apt/lists/*
 
-RUN update-alternatives --install /usr/bin/python python /usr/bin/python3.9 1
-ENV PYTHON_VERSION=3
+ENV PYTHON_VERSION=3 \
+    PIP_BREAK_SYSTEM_PACKAGES=1
 RUN pip3 install --upgrade pip setuptools wheel
 
 # Copy rustup_install_opts.txt file from builder
@@ -280,9 +291,8 @@ RUN apt-get update && \
       socat \
       inotify-tools \
       jq \
-      python3.9 \
-      python3-pip \
-      libpq5 && \
+      python3 \
+      python3-pip && \
     apt-get clean && \
     rm -rf /var/lib/apt/lists/*
 
@@ -295,6 +305,12 @@ RUN mkdir $LIGHTNINGD_DATA && \
     touch $LIGHTNINGD_DATA/config
 VOLUME [ "/root/.lightning" ]
 
+# Take libpq directly from builder.
+RUN mkdir /var/libpq && mkdir -p /usr/local/pgsql/lib
+RUN --mount=type=bind,from=builder,source=/var/libpq,target=/var/libpq,rw \
+    cp -a /var/libpq/libpq.* /usr/local/pgsql/lib && \
+    ldconfig /usr/local/pgsql/lib
+
 COPY --from=builder /tmp/lightning_install/ /usr/local/
 COPY --from=builder-python /usr/local/lib/python3.9/dist-packages/ /usr/local/lib/python3.9/dist-packages/
 COPY --from=downloader /opt/bitcoin/bin /usr/bin