ci: Use prebuilt Docker images

Don't waste precious CI time reinstalling/upgrading packages.

Most of the scripts here were taken from GLib's CI scripts, but adjusted
to deal with dependencies that might change between branches rather than
different distros.

1 files changed, 25 insertions, 0 deletions

diff --git a/.gitlab-ci/README.md b/.gitlab-ci/README.md
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+# CI support stuff
+
+## Docker image
+
+GitLab CI jobs run in a Docker image, defined here. To update that image
+(perhaps to install some more packages):
+
+1. Edit `.gitlab-ci/$BRANCH.Dockerfile` with the changes you want
+1. Run `.gitlab-ci/run-docker.sh build --branch=$BRANCH --version=1` to build
+   the new image (bump the version from the latest listed for the main branch)
+   https://gitlab.gnome.org/GNOME/libsecret/container_registry). If `--branch`
+   is not specified, it will use the default branch
+1. Run `.gitlab-ci/run-docker.sh push --branch=$BRANCH --version=1` to upload
+   the new image to the GNOME GitLab Docker registry
+    * If this is the first time you're doing this, you'll need to log into the
+      registry
+    * If you use 2-factor authentication on your GNOME GitLab account, you'll
+      need to [create a personal access token][pat] and use that rather than
+      your normal password — the token should have `read_registry` and
+      `write_registry` permissions
+1. Edit `.gitlab-ci.yml` (in the root of this repository) to use your new
+   image
+
+[pat]: https://gitlab.gnome.org/-/profile/personal_access_tokens
+[cs]: https://scan.coverity.com/