Automatically update JRE base images

Dockerfile.template

@@ -1,7 +1,7 @@
 {{
 	def major: env.version | split(".")[0] | tonumber
 -}}
-FROM eclipse-temurin:{{ .java }}-jre-focal
+FROM {{ .FROM.version }}
 
 # explicitly set user/group IDs
 RUN set -eux; \

generate-stackbrew-library.sh

@@ -82,6 +82,11 @@ for version; do
 	fi
 	versionAliases+=( ${aliases[$version]:-} )
 
+	suite="$(jq -r '.[env.version].FROM.base' versions.json)"
+	suiteAliases=( "${versionAliases[@]/%/-$suite}" )
+	suiteAliases=( "${suiteAliases[@]//latest-/}" )
+	versionAliases+=( "${suiteAliases[@]}" )
+
 	parent="$(awk 'toupper($1) == "FROM" { print $2 }' "$version/Dockerfile")"
 	arches="${parentRepoToArches[$parent]}"
 

versions.json

@@ -1,27 +1,57 @@
 {
   "3.0": {
-    "java": "8",
+    "version": "3.0.29",
     "sha512": "31515e20fb1356ae8cf277c52954ea711c4e158f852cd8bee096775f1f0a2b6847fe972d4755f061b45578f7ed688237b8ead84b38c77bcccfd6f8c022db520b",
-    "version": "3.0.29"
+    "java": {
+      "version": "8"
+    },
+    "FROM": {
+      "version": "eclipse-temurin:8-jre-focal",
+      "base": "focal"
+    }
   },
   "3.11": {
-    "java": "8",
+    "version": "3.11.16",
     "sha512": "5bc76508fec8ff9d4fcfa3c53b0c9550ef37ad771e568b2634df2ba5377c378237c968f1d2bfb1078ecc30c034aea63b4c481826bb9ac26536f1f4f336cd8286",
-    "version": "3.11.16"
+    "java": {
+      "version": "8"
+    },
+    "FROM": {
+      "version": "eclipse-temurin:8-jre-focal",
+      "base": "focal"
+    }
   },
   "4.0": {
-    "java": "11",
+    "version": "4.0.11",
     "sha512": "92bd35819e86927709add1075023af5aed93d42e0115bfa6b675b15e93b31bffa6fd3b9ff95a403bb9650ec417a0567ac776c88b56fe373938451746bbc64a50",
-    "version": "4.0.11"
+    "java": {
+      "version": "11"
+    },
+    "FROM": {
+      "version": "eclipse-temurin:11-jre-focal",
+      "base": "focal"
+    }
   },
   "4.1": {
-    "java": "11",
+    "version": "4.1.3",
     "sha512": "393443a5b9849645362df2f7536e734e1fc6d513aadf440fab8dda3063553394a138805098796d35f9d4d31e2899ecab630a2ec2a44d00d5e63bed549a2e844c",
-    "version": "4.1.3"
+    "java": {
+      "version": "11"
+    },
+    "FROM": {
+      "version": "eclipse-temurin:11-jre-focal",
+      "base": "focal"
+    }
   },
   "5.0": {
-    "java": "17",
+    "version": "5.0-beta1",
     "sha512": "d67aa211858f090dca6ea2ac84ed405bd4791aaf493e3c8e5b24fd44e54aa3132eeca3f4e310d6d1aad1ca105515011d6e177d169a6e94af0a257ffc95b4f175",
-    "version": "5.0-beta1"
+    "java": {
+      "version": "17"
+    },
+    "FROM": {
+      "version": "eclipse-temurin:17-jre-focal",
+      "base": "focal"
+    }
   }
 }

versions.sh

@@ -50,15 +50,30 @@ for version in "${versions[@]}"; do
 
 	export javaVersion="${javaVersions[$version]:-$defaultJavaVersion}"
 
-	echo "$version: $fullVersion"
+	# for the given Java version, find the "default" Eclipse Temurin tag with stable specificity ("X-jre-SUITE")
+	from="$(
+		bashbrew --arch amd64 list --arch-filter "https://github.com/docker-library/official-images/raw/HEAD/library/eclipse-temurin:$javaVersion-jre" \
+			| grep -F ":$javaVersion-jre-" \
+			| tail -1
+	)"
+	export from
+
+	echo "$version: $fullVersion (FROM $from)"
 
 	json="$(jq <<<"$json" -c '
 		.[env.version] = {
 			version: env.fullVersion,
 			sha512: env.sha512,
-			java: env.javaVersion,
+			java: {
+				version: env.javaVersion,
+			},
+			FROM: {
+				# this structure is a little bit awkward, but gives us nice commit messages like "Update 5.0 to FROM eclipse-temurin:17-jre-jammy"
+				version: env.from,
+				base: (env.from | split(":\(env.javaVersion)-jre-")[1]),
+			},
 		}
 	')"
 done
 
-jq <<<"$json" -S . > versions.json
+jq <<<"$json" . > versions.json