feat: support docker/metadata-action for tags on GitHub

Author: wdconinc

containers/debian/base.hcl

@@ -4,7 +4,19 @@ variable "BUILD_IMAGE" { default = "debian_base" }
 # Variables whose defaults can be overridden on build
 variable "BASE_IMAGE" { default = null }
 
+# docker/metadata-action overrides the following target with tags
+# but we implement it for use outside docker/metadata-action
+target "docker-metadata-action" {
+  tags = compact(flatten([
+    join("/", compact([ CI_REGISTRY, CI_PROJECT_PATH, "${BUILD_IMAGE}:${INTERNAL_TAG}"]) ),
+    EXPORT_TAG != null && EXPORT_TAG != "" ? [
+      for registry in registries: "${registry}/${BUILD_IMAGE}:${EXPORT_TAG}"
+    ] : [ null ]
+  ]))
+}
+
 target "default" {
+  inherits = ["docker-metadata-action"]
   attest = [
     "type=provenance,disabled=true"
   ]
@@ -15,10 +27,4 @@ target "default" {
     BASE_IMAGE = BASE_IMAGE
     BUILD_IMAGE = BUILD_IMAGE
   }
-  tags = compact(flatten([
-    join("/", compact([ CI_REGISTRY, CI_PROJECT_PATH, "${BUILD_IMAGE}:${INTERNAL_TAG}"]) ),
-    EXPORT_TAG != null && EXPORT_TAG != "" ? [
-      for registry in registries: "${registry}/${BUILD_IMAGE}:${EXPORT_TAG}"
-    ] : [ null ]
-  ]))
 }

containers/jug/dev.hcl

@@ -28,7 +28,23 @@ image_names = [
   replace(image_name,"eic","jug")
 ]
 
+# docker/metadata-action overrides the following target with tags
+# but we implement it for use outside docker/metadata-action
+target "docker-metadata-action" {
+  tags = compact(flatten([
+    [
+      for image_name in image_names:
+        join("/", compact([ CI_REGISTRY, CI_PROJECT_PATH, "${image_name}:${INTERNAL_TAG}"]) )
+    ],
+    EXPORT_TAG != null && EXPORT_TAG != "" ? [
+      for registry_image_name in setproduct(registries, image_names):
+        format("%s:%s", join("/", registry_image_name), EXPORT_TAG )
+    ] : [ null ]
+  ]))
+}
+
 target "default" {
+  inherits = ["docker-metadata-action"]
   attest = [
     "type=provenance,disabled=true"
   ]
@@ -63,14 +79,4 @@ target "default" {
     EPIC_VERSION = BUILD_TYPE == "default" ? EPIC_VERSION : "main"
     JUGGLER_VERSION = BUILD_TYPE == "default" ? JUGGLER_VERSION : "main"
   }
-  tags = compact(flatten([
-    [
-      for image_name in image_names:
-        join("/", compact([ CI_REGISTRY, CI_PROJECT_PATH, "${image_name}:${INTERNAL_TAG}"]) )
-    ],
-    EXPORT_TAG != null && EXPORT_TAG != "" ? [
-      for registry_image_name in setproduct(registries, image_names):
-        format("%s:%s", join("/", registry_image_name), EXPORT_TAG )
-    ] : [ null ]
-  ]))
 }