[CMSP-391][CI] Ensure a cde is available for testing (#51)

.circleci/config.yml

@@ -1,19 +1,38 @@
 version: 2.1
 # https://circleci.com/docs/configuration#machine
+executors:
+  build-tools:
+    docker:
+      - image: quay.io/pantheon-public/build-tools-ci:8.x-php7.4
+
+commands:
+    login-pantheon:
+        steps:
+            - run:
+                name: Login with Terminus
+                command: terminus auth:login -n --machine-token="$TERMINUS_TOKEN"
+
 jobs:
+    ensure_multidevs:
+        executor: build-tools
+        environment:
+            TERMINUS_SITE: d9-papc3
+        steps:
+            - login-pantheon
+            - checkout
+            - run: 
+                name: Ensure enough multidev environments are available
+                command: bash .circleci/scripts/ensure-available-multidev.sh "$TERMINUS_SITE" 2
     build:
         parameters:
             base-env:
                 type: string
-        docker:
-            - image: quay.io/pantheon-public/build-tools-ci:8.x-php7.4
+        executor: build-tools
         environment:
             TERMINUS_SITE: d9-papc3
             TERMINUS_BASE_ENV: << parameters.base-env >>
         steps:
-            - run:
-                name: login-pantheon
-                command: terminus auth:login -n --machine-token="$TERMINUS_TOKEN"
+            - login-pantheon
             # Start making a multidev right away in the background so that
             # this slow step is done as soon as possible.
             - run:
@@ -97,7 +116,11 @@ jobs:
 workflows:
   build:
     jobs:
+      - ensure_multidevs:
+          name: Ensure There are Enough Multidevs
       - build:
+          requires:
+            - Ensure There are Enough Multidevs
           matrix:
             parameters:
               base-env: [dev, drupal10]

.circleci/scripts/ensure-available-multidev.sh

@@ -0,0 +1,62 @@
+#!/bin/bash
+set -euo pipefail
+IFS=$'\n\t'
+###
+# Given a site name, ensure we can create a new multidev, or delete the oldest one.
+###
+
+usage_exit(){
+    echo "usage: $0 site_name multidev_count"
+    exit 1
+}
+
+SITE_NAME="${1:-}"
+if [[ -z "${SITE_NAME}" ]];then
+    echo "Missing Site Name"
+    usage_exit
+fi
+
+NUMBER_OF_CDES_REQUIRED="${2:-}"
+if [[ "${NUMBER_OF_CDES_REQUIRED}" == "" ]]; then
+    echo "No multidev count provided, assuming 1."
+    NUMBER_OF_CDES_REQUIRED=1
+elif ! [[ $NUMBER_OF_CDES_REQUIRED =~ ^[0-9]+$ ]]; then
+    echo "The variable is not an integer."
+    usage_exit
+fi
+
+MAX_CDE_COUNT="$(terminus site:info "${SITE_NAME}" --field='Max Multidevs')"
+echo "Max Multidev Count: ${MAX_CDE_COUNT}"
+
+DOMAINS="$(terminus env:list "${SITE_NAME}" --format=string --fields=ID,Created)"
+
+# Filter out dev, test, live as they don't count agains the Max Multidev count.
+CDE_DOMAINS=$(echo "$DOMAINS" | grep -vE '\b(dev|test|live)\b')
+
+# Count current environments
+CDE_COUNT="$(echo "$CDE_DOMAINS" | wc -l)"
+# remove whitespace to make the arithmetic work
+CDE_COUNT="${CDE_COUNT//[[:blank:]]/}"
+
+echo "There are currently ${CDE_COUNT}/${MAX_CDE_COUNT} multidevs. I need ${NUMBER_OF_CDES_REQUIRED}."
+
+POTENTIAL_CDE_COUNT=$((CDE_COUNT + NUMBER_OF_CDES_REQUIRED))
+if [[ "${POTENTIAL_CDE_COUNT}" -le "${MAX_CDE_COUNT}" ]]; then
+  echo "There are enough multidevs."
+  exit
+fi
+
+NUMBER_OF_CDES_TO_DELETE=$((POTENTIAL_CDE_COUNT - MAX_CDE_COUNT))
+echo "There are not enough multidevs, deleting the oldest ${NUMBER_OF_CDES_TO_DELETE} environment(s)."
+
+# Filter out any multidev environments that should never be deleted.
+# This is seperate from filtering out dev/test/live above as they still count towards 'Max Multidev'.
+# Then, sort the list by the timestamps
+SORTED_DOMAINS=$(echo "$CDE_DOMAINS" | grep -vE '\b(drupal10)\b' | sort -n -k2)
+
+# Delete as many multidevs as we need to make room for testing.
+for (( i = 1; i<=NUMBER_OF_CDES_TO_DELETE; i++ )); do
+    ENV_TO_REMOVE="$(echo "$SORTED_DOMAINS" | head -n "$i" | tail -n 1 | cut -f1)"
+    echo "Removing '${ENV_TO_REMOVE}'."
+    terminus multidev:delete --delete-branch "${SITE_NAME}.${ENV_TO_REMOVE}" --yes
+done