Use base_images so we can build 7 and 8 ES images

images/elasticsearch/Dockerfile

@@ -1,6 +1,6 @@
 FROM [[ .docker.repo ]][[ .docker.base_images.alpine.image ]] AS builder
 
-ARG ES_VERSION=[[ .elasticsearch.server.version ]]
+ARG ES_VERSION=[[ .docker.base_images.elasticsearch8.build_args.ES_VERSION ]]
 
 RUN set -eux &&\
     apk add ca-certificates curl tar &&\

prep.d/10-build-base-images.sh

@@ -0,0 +1 @@
+[[ template "common/build_base_images.sh" . ]]

variables.yml

@@ -18,11 +18,9 @@ elasticsearch:
 
   # ES server settings
   server:
-    # ES version
-    version: 8.12.2
 
     # Docker image to use
-    image: '[[ .docker.repo ]]elasticsearch:[[ .elasticsearch.server.version ]]-1'
+    image: '[[ .docker.repo ]][[ .docker.base_images.elasticsearch8.image ]]'
 
     # Number of instances
     count: 3
@@ -123,3 +121,23 @@ elasticsearch:
     # Metrics URL, as seen from inside the alloc
     metrics_url: http://127.0.0.1:9114/metrics
 
+
+docker:
+
+  # Define base_images so we can easily build 7 and 8 variants of the image
+  base_images:
+    elasticsearch7:
+      image: elasticsearch:[[ .docker.base_images.elasticsearch7.build_args.ES_VERSION ]]-2
+      build_args:
+        ES_VERSION: 7.17.18
+      tags:
+        - elasticsearch:7
+        - elasticsearch7:latest
+
+    elasticsearch8:
+      image: elasticsearch:[[ .docker.base_images.elasticsearch8.build_args.ES_VERSION ]]-2
+      build_args:
+        ES_VERSION: 8.12.2
+      tags:
+        - elasticsearch:8
+        - elasticsearch8:latest