Prepared definition of application docker image

• Application image based on Caddy server (nginx didn't work correctly)
• defined CI steps to build the image on CI

scripts/ci-helpers/build_instance.sh

+#! /bin/bash
+set -euo pipefail
+
+SCRIPTPATH="$( cd -- "$(dirname "$0")" >/dev/null 2>&1 ; pwd -P )"
+SCRIPTSDIR="$SCRIPTPATH/.."
+
+print_help () {
+cat <<-EOF
+  Usage: $0 <image_tag> <src_dir> <registry_url> [OPTION[=VALUE]]...
+
+  Builds docker image containing Hive Bridge application installation, ready to run. To spawn it, just run a container and map port 8080 to the host.
+  OPTIONS:
+      --help|-h|-?      Display this help screen and exit
+      --progress=TYPE   Determines how to display build progress (default: 'auto')
+      --push            Allows to automatically push built image to the registry
+EOF
+}
+
+PROGRESS_DISPLAY=${PROGRESS_DISPLAY:-"auto"}
+IMAGE_OUTPUT="--load"
+
+BUILD_IMAGE_TAG=""
+REGISTRY=""
+SRCROOTDIR=""
+
+while [ $# -gt 0 ]; do
+  case "$1" in
+    --help|-h|-?)
+        print_help
+        exit 0
+        ;;
+    --progress=*)
+      arg="${1#*=}"
+      PROGRESS_DISPLAY="$arg"
+      ;;
+
+    --push)
+      IMAGE_OUTPUT="--push"
+      ;;
+
+    *)
+    if [ -z "$BUILD_IMAGE_TAG" ];
+    then
+        BUILD_IMAGE_TAG="${1}"
+    elif [ -z "$SRCROOTDIR" ];
+    then
+        SRCROOTDIR="${1}"
+    elif [ -z "$REGISTRY" ];
+    then
+        REGISTRY=${1}
+    else
+        echo "ERROR: '$1' is not a valid option/positional argument"
+        echo
+        print_help
+        exit 2
+    fi
+    ;;
+    esac
+    shift
+done
+
+
+_TST_IMGTAG=${BUILD_IMAGE_TAG:?"Missing arg #1 to specify built image tag"}
+_TST_SRCDIR=${SRCROOTDIR:?"Missing arg #2 to specify source directory"}
+_TST_REGISTRY=${REGISTRY:?"Missing arg #3 to specify target container registry"}
+
+# Supplement a registry path by trailing slash (if needed)
+#[[ "${REGISTRY}" != */ ]] && REGISTRY="${REGISTRY}/"
+
+echo "Moving into source root directory: ${SRCROOTDIR}"
+
+pushd "$SRCROOTDIR"
+
+export DOCKER_BUILDKIT=1
+BUILD_TIME="$(date -uIseconds)"
+GIT_COMMIT_SHA="$(git rev-parse HEAD || true)"
+if [ -z "$GIT_COMMIT_SHA" ]; then
+  GIT_COMMIT_SHA="[unknown]"
+fi
+
+GIT_CURRENT_BRANCH="$(git branch --show-current || true)"
+if [ -z "$GIT_CURRENT_BRANCH" ]; then
+  GIT_CURRENT_BRANCH="$(git describe --abbrev=0 --all | sed 's/^.*\///' || true)"
+  if [ -z "$GIT_CURRENT_BRANCH" ]; then
+    GIT_CURRENT_BRANCH="[unknown]"
+  fi
+fi
+
+GIT_LAST_LOG_MESSAGE="$(git log -1 --pretty=%B || true)"
+if [ -z "$GIT_LAST_LOG_MESSAGE" ]; then
+  GIT_LAST_LOG_MESSAGE="[unknown]"
+fi
+
+GIT_LAST_COMMITTER="$(git log -1 --pretty="%an <%ae>" || true)"
+if [ -z "$GIT_LAST_COMMITTER" ]; then
+  GIT_LAST_COMMITTER="[unknown]"
+fi
+
+GIT_LAST_COMMIT_DATE="$(git log -1 --pretty="%aI" || true)"
+if [ -z "$GIT_LAST_COMMIT_DATE" ]; then
+  GIT_LAST_COMMIT_DATE="[unknown]"
+fi
+
+echo -e "\nBuilding base instance image...\n"
+
+docker buildx build --target=app \
+  --progress="$PROGRESS_DISPLAY" \
+  --build-arg BUILD_TIME="$BUILD_TIME" \
+  --build-arg GIT_COMMIT_SHA="$GIT_COMMIT_SHA" \
+  --build-arg GIT_CURRENT_BRANCH="$GIT_CURRENT_BRANCH" \
+  --build-arg GIT_LAST_LOG_MESSAGE="$GIT_LAST_LOG_MESSAGE" \
+  --build-arg GIT_LAST_COMMITTER="$GIT_LAST_COMMITTER" \
+  --build-arg GIT_LAST_COMMIT_DATE="$GIT_LAST_COMMIT_DATE" \
+  --tag "${REGISTRY}:${BUILD_IMAGE_TAG}" \
+  "${IMAGE_OUTPUT}" \
+  --file Dockerfile "$SRCROOTDIR"
+
+echo -e "\nDone!\nBuilding instance image...\n"
+
+echo "APP_IMAGE_NAME=$REGISTRY:$BUILD_IMAGE_TAG" > app_docker_image_name.env
+{
+  echo "APP_IMAGE_VERSION=$BUILD_IMAGE_TAG"
+} >> app_docker_image_name.env
+
+popd
\ No newline at end of file