ci: guess some environment variables based on builder name and os

Some environment variables (like DEPLOY or DEPLOY_ALT for dist builders,
or IMAGE on Linux builders) are set on a lot of builders, and whether
they should be present or not can be detected automatically based on the
builder name and the platform.

This commit simplifies the CI configuration by automatically setting
those environment variables.

1 files changed, 31 insertions, 0 deletions

diff --git a/src/ci/scripts/setup-environment.sh b/src/ci/scripts/setup-environment.sh
new file mode 100755
index 00000000000..e126a06edab
--- /dev/null
+++ b/src/ci/scripts/setup-environment.sh
@@ -0,0 +1,31 @@
+#!/bin/bash
+# This script guesses some environment variables based on the builder name and
+# the current platform, to reduce the amount of variables defined in the CI
+# configuration.
+
+set -euo pipefail
+IFS=$'\n\t'
+
+source "$(cd "$(dirname "$0")" && pwd)/../shared.sh"
+
+# Builders starting with `dist-` are dist builders, but if they also end with
+# `-alt` they are alternate dist builders.
+if [[ "${CI_JOB_NAME}" = dist-* ]]; then
+    if [[ "${CI_JOB_NAME}" = *-alt ]]; then
+        echo "alternate dist builder detected, setting DEPLOY_ALT=1"
+        ciCommandSetEnv DEPLOY_ALT 1
+    else
+        echo "normal dist builder detected, setting DEPLOY=1"
+        ciCommandSetEnv DEPLOY 1
+    fi
+fi
+
+# All the Linux builds happen inside Docker.
+if isLinux; then
+    if [[ -z "${IMAGE+x}" ]]; then
+        echo "linux builder detected, using docker to run the build"
+        ciCommandSetEnv IMAGE "${CI_JOB_NAME}"
+    else
+        echo "a custom docker image is already set"
+    fi
+fi