Adds dockerfile variable to configure air-gapped hosting server as replacement for github.com

external-dependencies/googletest/Dockerfile

@@ -55,23 +55,26 @@ RUN curl -fsSL http://${RME_ADMINSRV}/rme/deb_and_rpm_signage_key.pub --output /
 
 ARG GTEST_VERSION=1.15.2
 
+# Air-gapped Harbor registry URL
+ARG HARBOR_URL=https://internal-repo.sl.defence-elec.de
+
 # Install build dependencies
 RUN apt-get update && apt-get install -y --no-install-recommends \
-    build-essential cmake git \
+    build-essential cmake curl \
     && rm -rf /var/lib/apt/lists/*
 
-# Clone and build GoogleTest
-RUN git clone --depth 1 --branch v${GTEST_VERSION} \
-    https://github.com/google/googletest.git /tmp/googletest \
-    && cd /tmp/googletest \
-    && mkdir build && cd build \
-    && cmake -DCMAKE_BUILD_TYPE=Release \
-             -DCMAKE_INSTALL_PREFIX=/usr/local \
-             -DBUILD_SHARED_LIBS=ON \
-             .. \
-    && cmake --build . -j$(nproc) \
-    && cmake --install . \
-    && rm -rf /tmp/googletest
+# Download and build GoogleTest from air-gapped Harbor registry
+RUN curl -L -o /tmp/googletest-${GTEST_VERSION}.tar.gz ${HARBOR_URL}/googletest-${GTEST_VERSION}.tar.gz && \
+    tar -xzf /tmp/googletest-${GTEST_VERSION}.tar.gz -C /tmp && \
+    cd /tmp/googletest-${GTEST_VERSION} && \
+    mkdir build && cd build && \
+    cmake -DCMAKE_BUILD_TYPE=Release \
+          -DCMAKE_INSTALL_PREFIX=/usr/local \
+          -DBUILD_SHARED_LIBS=ON \
+          .. && \
+    cmake --build . -j$(nproc) && \
+    cmake --install . && \
+    rm -rf /tmp/googletest-${GTEST_VERSION}.tar.gz /tmp/googletest-${GTEST_VERSION}
 
 # Update library cache
 RUN ldconfig