Add build stage for continuous integration

.gitlab-ci.yml:
Add a build stage to the gitlab CI, that facilitates the scripts below .gitlab/ci/, building the baseline and releng
profiles in parallel.
Distinguish the use-case in which builds are done for master, schedules and tags in a secure environment and any other
where builds just have to be fast (for ensuring nothing is broken).

Use MiB as block size for the du call when generating data for the metrics file.

1 files changed, 45 insertions, 4 deletions

diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index dbb2dde..a768c0f 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -3,11 +3,52 @@
 # SPDX-License-Identifier: GPL-3.0-or-later
 
 default:
-  image: archlinux:latest
+  image: "archlinux:latest"
+
+stages:
+  - lint
+  - build
+
+shellcheck:
+  stage: lint
   before_script:
-    - pacman --noconfirm -Syu --needed base-devel shellcheck
+    - pacman --noconfirm -Syu --needed make shellcheck
+  script:
+    - make lint
 
-lint:
+.build:
   stage: build
+  before_script:
+    - pacman -Syu --needed --noconfirm qemu-headless libisoburn
   script:
-    - make lint
+    - ./.gitlab/ci/build-host.sh
+  after_script:
+    - echo "image_size_megabytes{image=\"${PROFILE}\"} $(du --block-size=MiB -- output/${PROFILE}/*iso)" > metrics.txt
+  parallel:
+    matrix:
+      - PROFILE: [baseline, releng]
+  artifacts:
+    name: "output"
+    paths:
+      - "output/*/*"
+    expire_in: 2d
+    reports:
+      metrics: metrics.txt
+
+build:
+  extends: .build
+  tags:
+    - fast-single-thread
+  except:
+    - master
+    - schedules
+    - tags
+
+build:secure:
+  extends: .build
+  tags:
+    - secure
+  only:
+    - master
+    - schedules
+    - tags