.GoBuild:
  image: golang:1.19-buster # don't use alpine because of musl libc

  variables:
    BINARY_NAME: "$CI_PROJECT_NAME"
    BINARY_DIR: "$CI_PROJECT_DIR/dist"

    EXTRA_GO_BUILD_ARGS: ""
    EXTRA_LD_FLAGS: ""
    LD_FLAGS: "-s -w"
    USE_UPX: "true"

    GO_VERSION_VARIABLE: "" # package.variable to set to CI_COMMIT_REF_NAME
    GO_VERSION_INFO_VARIABLE: "" # package.variable to set to additional data about release

    PACKAGE_COMMIT_ENABLE: "true"
    PACKAGE_COMMIT_PREFIX: "commit-"

    PACKAGE_REF_SLUG_ENABLE: "true"

    RUN_BINARY: "false"
    RUN_BINARY_WITH_ARGUMENTS: ""

  before_script:
    - apt update
    - apt install -y curl upx-ucl

  script:
    # set a default for the BINARY_NAME to allow job to run in local gitlab-runner when testing
    - if [[ ! -z "$BINARY_NAME" ]]; then BINARY_NAME="app"; fi

    # prepare build args
    - |
      if [[ ! -z "GO_VERSION_VARIABLE" ]]; then
        LD_FLAGS="$LD_FLAGS -X '$GO_VERSION_VARIABLE=$CI_COMMIT_REF_NAME'"
      fi
      if [[ ! -z "GO_VERSION_INFO_VARIABLE" ]]; then
        LD_FLAGS="$LD_FLAGS -X '$GO_VERSION_INFO_VARIABLE=ref: $CI_COMMIT_REF_NAME commit: $CI_COMMIT_SHA'"
      fi

    # build
    - go build -ldflags="$LD_FLAGS $EXTRA_LD_FLAGS" -o "$BINARY_DIR/$BINARY_NAME" $EXTRA_GO_BUILD_ARGS ./main.go

    # run UPX to compress binary if enabled
    - if [[ "$USE_UPX" == true ]]; then upx $BINARY_DIR/$BINARY_NAME; fi

    # test run binary
    - |
      if [[ "$RUN_BINARY" == "true" ]]; then
        $BINARY_DIR/$BINARY_NAME $RUN_BINARY_WITH_ARGUMENTS
        RC=$?
      fi

    # publish package for commit
    - |
      if [[ "$PACKAGE_COMMIT_ENABLE" == "true" ]] && [[ ! -z "$CI_API_V4_URL" ]]; then
        curl \
          --header "JOB-TOKEN: $CI_JOB_TOKEN" \
          --upload-file $BINARY_DIR/$BINARY_NAME \
          "${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/packages/generic/$BINARY_NAME/$IMAGE_COMMIT_PREFIX-$CI_COMMIT_SHA/$BINARY_NAME"
      fi

    # publish package for commit ref slug
    - |
      if [[ "$PACKAGE_REF_SLUG_ENABLE" == "true" ]] && [[ ! -z "$CI_API_V4_URL" ]]; then
        curl \
          --header "JOB-TOKEN: $CI_JOB_TOKEN" \
          --upload-file $BINARY_DIR/$BINARY_NAME \
          "${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/packages/generic/$BINARY_NAME/$CI_COMMIT_REF_SLUG/$BINARY_NAME"
      fi