chore: allow to build and publish experimental Linux images

Jenkinsfile

@@ -52,7 +52,12 @@ def parallelStages = [failFast: false]
     'windowsservercore-ltsc2022'
 ].each { imageType ->
     parallelStages[imageType] = {
-        withEnv(["IMAGE_TYPE=${imageType}", "REGISTRY_ORG=${infra.isTrusted() ? 'jenkins' : 'jenkins4eval'}"]) {
+        withEnv([
+            "IMAGE_TYPE=${imageType}",
+            "REGISTRY_ORG=${infra.isTrusted() ? 'jenkins' : 'jenkins4eval'}",
+            // Set to "true" to enable experimental image(s) publication
+            "PUBLISH_EXPERIMENTAL=false"
+        ]) {
             int retryCounter = 0
             retry(count: 2, conditions: [agent(), nonresumable()]) {
                 // Use local variable to manage concurrency and increment BEFORE spinning up any agent

Makefile

@@ -82,6 +82,9 @@ prepare-test: bats check-reqs
 publish:
 	@set -x; $(bake_base_cli) linux --push
 
+# Strip experimental prefix if present
+strip_experimental = $(patsubst experimental-jlink_%,%,$(1))
+
 ## Define bats options based on environment
 # common flags for all tests
 bats_flags := ""
@@ -105,9 +108,9 @@ test-%: prepare-test
 # Each type of image ("agent" or "inbound-agent") has its own tests suite
 ifeq ($(CI), true)
 # Execute the test harness and write result to a TAP file
-	IMAGE=$* bats/bin/bats $(CURDIR)/tests/tests_$(shell echo $* |  cut -d "_" -f 1).bats $(bats_flags) --formatter junit | tee target/junit-results-$*.xml
+	IMAGE=$(call strip_experimental,$*) bats/bin/bats $(CURDIR)/tests/tests_$(shell echo $(call strip_experimental,$*) |  cut -d "_" -f 1).bats $(bats_flags) --formatter junit | tee target/junit-results-$*.xml
 else
-	IMAGE=$* bats/bin/bats $(CURDIR)/tests/tests_$(shell echo $* |  cut -d "_" -f 1).bats $(bats_flags)
+	IMAGE=$(call strip_experimental,$*) bats/bin/bats $(CURDIR)/tests/tests_$(shell echo $(call strip_experimental,$*) |  cut -d "_" -f 1).bats $(bats_flags)
 endif
 
 test: prepare-test

alpine/Dockerfile

@@ -41,8 +41,9 @@ RUN apk add --no-cache \
 
 ENV PATH="/opt/jdk-${JAVA_VERSION}/bin:${PATH}"
 
+ARG EXPERIMENTAL_JLINK=false
 RUN java_major_version="$(jlink --version 2>&1 | cut -c1-2)"; \
-  if [[ "${TARGETPLATFORM}" == "linux/arm/v7" || "${java_major_version}" == 25 ]]; then \
+  if test "${EXPERIMENTAL_JLINK}" = "false" && [ "${TARGETPLATFORM}" = "linux/arm/v7" ] || [ "${java_major_version}" = "25" ]; then \
     # It is acceptable to have a larger image in arm/v7 (arm 32 bits) environment
     # because jlink fails with the error "jmods: Value too large for defined data type" error.
     # For JDK25, we need to have a proper test and validation process first cf https://github.com/jenkinsci/docker-agents/issues/1124)
@@ -52,6 +53,8 @@ RUN java_major_version="$(jlink --version 2>&1 | cut -c1-2)"; \
     case "$(jlink --version 2>&1 | cut -c1-2)" in \
       "17") options="--compress=2 --add-modules ALL-MODULE-PATH" ;; \
       "21") options="--compress=zip-6 --add-modules ALL-MODULE-PATH" ;; \
+      # Experimental
+      "25") options="--compress=zip-6 --add-modules java.base,java.logging,java.xml,java.se";; \
       *) echo "ERROR: unmanaged jlink version pattern" && exit 1 ;; \
     esac; \
     jlink \

debian/Dockerfile

@@ -45,8 +45,9 @@ ENV PATH="/opt/jdk-${JAVA_VERSION}/bin:${PATH}"
 # Generate smaller java runtime without unneeded files
 # for now we include the full module path to maintain compatibility
 # while still saving space (approx 200mb from the full distribution)
+ARG EXPERIMENTAL_JLINK=false
 RUN java_major_version="$(jlink --version 2>&1 | cut -c1-2)"; \
-  if [[ "${TARGETPLATFORM}" == "linux/arm/v7" || "${java_major_version}" == 25 ]]; then \
+  if test "${EXPERIMENTAL_JLINK}" = "false" && [ "${TARGETPLATFORM}" = "linux/arm/v7" ] || [ "${java_major_version}" = "25" ]; then \
     # It is acceptable to have a larger image in arm/v7 (arm 32 bits) environment
     # because jlink fails with the error "jmods: Value too large for defined data type" error.
     # For JDK25, we need to have a proper test and validation process first cf https://github.com/jenkinsci/docker-agents/issues/1124)
@@ -56,6 +57,8 @@ RUN java_major_version="$(jlink --version 2>&1 | cut -c1-2)"; \
     case "$(jlink --version 2>&1 | cut -c1-2)" in \
       "17") options="--compress=2 --add-modules ALL-MODULE-PATH" ;; \
       "21") options="--compress=zip-6 --add-modules ALL-MODULE-PATH" ;; \
+      # Experimental
+      "25") options="--compress=zip-6 --add-modules java.base,java.logging,java.xml,java.se";; \
       *) echo "ERROR: unmanaged jlink version pattern" && exit 1 ;; \
     esac; \
     jlink \

docker-bake.hcl

@@ -14,6 +14,18 @@ variable "jdks_in_preview" {
   default = []
 }
 
+# List of inbound agent target(s) to use as base of experimental images.
+# Default to inbound-agent image as it makes more sense to test that than the base agent one.
+# Note: omit "inbound-agent_" from the target you chose from `make list`
+variable "experimental_jlink_targets" {
+  default = ["debian_jdk25"]
+}
+
+# Set to "true" to enable experimental image(s) tag publication
+variable "PUBLISH_EXPERIMENTAL" {
+  default = "false"
+}
+
 variable "JAVA17_VERSION" {
   default = "17.0.17_10"
 }
@@ -95,13 +107,12 @@ target "alpine" {
     jdk  = jdks_to_build
   }
   name       = "${type}_alpine_jdk${jdk}"
+  inherits = ["_common_args_jdk${jdk}"]
   target     = type
   dockerfile = "alpine/Dockerfile"
   context    = "."
   args = {
     ALPINE_TAG   = ALPINE_FULL_TAG
-    VERSION      = REMOTING_VERSION
-    JAVA_VERSION = "${javaversion(jdk)}"
   }
   tags      = concat(linux_tags(type, jdk, "alpine"), linux_tags(type, jdk, "alpine${ALPINE_SHORT_TAG}"))
   platforms = alpine_platforms(jdk)
@@ -113,13 +124,12 @@ target "debian" {
     jdk  = jdks_to_build
   }
   name       = "${type}_debian_jdk${jdk}"
+  inherits = ["_common_args_jdk${jdk}"]
   target     = type
   dockerfile = "debian/Dockerfile"
   context    = "."
   args = {
-    VERSION        = REMOTING_VERSION
     DEBIAN_RELEASE = DEBIAN_RELEASE
-    JAVA_VERSION   = "${javaversion(jdk)}"
   }
   tags      = linux_tags(type, jdk, "debian")
   platforms = debian_platforms(jdk)
@@ -131,13 +141,12 @@ target "rhel_ubi9" {
     jdk  = jdks_to_build
   }
   name       = "${type}_rhel_ubi9_jdk${jdk}"
+  inherits = ["_common_args_jdk${jdk}"]
   target     = type
   dockerfile = "rhel/ubi9/Dockerfile"
   context    = "."
   args = {
     UBI9_TAG     = UBI9_TAG
-    VERSION      = REMOTING_VERSION
-    JAVA_VERSION = "${javaversion(jdk)}"
   }
   tags      = linux_tags(type, jdk, "rhel-ubi9")
   platforms = rhel_ubi9_platforms(jdk)
@@ -150,13 +159,12 @@ target "nanoserver" {
     windows_version = windowsversions("nanoserver")
   }
   name       = "${type}_nanoserver-${windows_version}_jdk${jdk}"
+  inherits = ["_common_args_jdk${jdk}"]
   dockerfile = "windows/nanoserver/Dockerfile"
   context    = "."
   args = {
     JAVA_HOME             = "C:/openjdk-${jdk}"
-    JAVA_VERSION          = "${replace(javaversion(jdk), "_", "+")}"
     TOOLS_WINDOWS_VERSION = "${toolsversion(windows_version)}"
-    VERSION               = REMOTING_VERSION
     WINDOWS_VERSION_TAG   = windows_version
   }
   target    = type
@@ -171,26 +179,64 @@ target "windowsservercore" {
     windows_version = windowsversions("windowsservercore")
   }
   name       = "${type}_windowsservercore-${windows_version}_jdk${jdk}"
+  inherits = ["_common_args_jdk${jdk}"]
   dockerfile = "windows/windowsservercore/Dockerfile"
   context    = "."
   args = {
     JAVA_HOME             = "C:/openjdk-${jdk}"
-    JAVA_VERSION          = "${replace(javaversion(jdk), "_", "+")}"
     TOOLS_WINDOWS_VERSION = "${toolsversion(windows_version)}"
-    VERSION               = REMOTING_VERSION
     WINDOWS_VERSION_TAG   = windows_version
   }
   target    = type
   tags      = windows_tags(type, jdk, "windowsservercore-${windows_version}")
   platforms = ["windows/amd64"]
 }
 
+## Experimental targets
+target "experimental_jlink" {
+  matrix = {
+    bake_target = experimental_jlink_targets
+  }
+  name = "inbound-agent_${bake_target}_experimental-jlink"
+  inherits = ["inbound-agent_${bake_target}"]
+  args = {
+    EXPERIMENTAL_JLINK = "true"
+  }
+  labels = {
+    "org.opencontainers.image.title" = "Jenkins experimental ${bake_target} image using jlink"
+  }
+  # Assuming only experimenting on inbound-agent targets for now, can be revised if needed.
+  tags = ["${REGISTRY}/${orgrepo("inbound-agent")}:${REMOTING_VERSION}-${BUILD_NUMBER}-${bake_target}-experimental-jlink-not-prod-ready"]
+  # Output as image only if PUBLISH_EXPERIMENTAL is set to "true"
+  # Ref: https://docs.docker.com/build/bake/reference/#targetoutput
+  output = equal(PUBLISH_EXPERIMENTAL, "true") ? ["type=image"] : ["type=cacheonly"]
+}
+
+## Internal targets
+target "_base" {
+  args = {
+    VERSION = REMOTING_VERSION
+  }
+}
+
+target "_common_args" {
+  inherits = ["_base"]
+  matrix = {
+    jdk             = jdks_to_build
+  }
+  name = "_common_args_jdk${jdk}"
+  args = {
+    JAVA_VERSION = "${replace(javaversion(jdk), "_", "+")}"
+  }
+}
+
 ## Groups
 group "linux" {
   targets = [
     "alpine",
     "debian",
-    "rhel_ubi9"
+    "rhel_ubi9",
+    "experimental"
   ]
 }
 
@@ -228,6 +274,12 @@ group "linux-ppc64le" {
   ]
 }
 
+## Experimental groups
+group "experimental" {
+  targets = [
+    "experimental_jlink"
+  ]
+}
 
 ## Common functions
 # Return the registry organization and repository depending on the agent type

rhel/ubi9/Dockerfile

@@ -23,8 +23,9 @@ ENV PATH="/opt/jdk-${JAVA_VERSION}/bin:${PATH}"
 # Generate smaller java runtime without unneeded files
 # for now we include the full module path to maintain compatibility
 # while still saving space (approx 200mb from the full distribution)
+ARG EXPERIMENTAL_JLINK=false
 RUN java_major_version="$(jlink --version 2>&1 | cut -c1-2)"; \
-  if [[ "${TARGETPLATFORM}" == "linux/arm/v7" || "${java_major_version}" == 25 ]]; then \
+  if test "${EXPERIMENTAL_JLINK}" = "false" && [ "${TARGETPLATFORM}" = "linux/arm/v7" ] || [ "${java_major_version}" = "25" ]; then \
     # It is acceptable to have a larger image in arm/v7 (arm 32 bits) environment
     # because jlink fails with the error "jmods: Value too large for defined data type" error.
     # For JDK25, we need to have a proper test and validation process first cf https://github.com/jenkinsci/docker-agents/issues/1124)
@@ -34,6 +35,8 @@ RUN java_major_version="$(jlink --version 2>&1 | cut -c1-2)"; \
     case "$(jlink --version 2>&1 | cut -c1-2)" in \
       "17") options="--compress=2 --add-modules ALL-MODULE-PATH" ;; \
       "21") options="--compress=zip-6 --add-modules ALL-MODULE-PATH" ;; \
+      # Experimental
+      "25") options="--compress=zip-6 --add-modules java.base,java.logging,java.xml,java.se";; \
       *) echo "ERROR: unmanaged jlink version pattern" && exit 1 ;; \
     esac; \
     jlink \

tests/golden/expected_tags_linux.txt

@@ -37,6 +37,7 @@ docker.io/jenkins/agent:trixie
 docker.io/jenkins/agent:trixie-jdk17
 docker.io/jenkins/agent:trixie-jdk21
 docker.io/jenkins/agent:trixie-jdk25
+docker.io/jenkins/inbound-agent:3355.v388858a_47b_33-1-debian_jdk25-experimental-jlink-not-prod-ready
 docker.io/jenkins/inbound-agent:alpine
 docker.io/jenkins/inbound-agent:alpine-jdk17
 docker.io/jenkins/inbound-agent:alpine-jdk21

tests/golden/expected_tags_linux_on_tag.txt

@@ -62,6 +62,7 @@ docker.io/jenkins/inbound-agent:3355.v388858a_47b_33-1-alpine3.23
 docker.io/jenkins/inbound-agent:3355.v388858a_47b_33-1-alpine3.23-jdk17
 docker.io/jenkins/inbound-agent:3355.v388858a_47b_33-1-alpine3.23-jdk21
 docker.io/jenkins/inbound-agent:3355.v388858a_47b_33-1-alpine3.23-jdk25
+docker.io/jenkins/inbound-agent:3355.v388858a_47b_33-1-debian_jdk25-experimental-jlink-not-prod-ready
 docker.io/jenkins/inbound-agent:3355.v388858a_47b_33-1-jdk17
 docker.io/jenkins/inbound-agent:3355.v388858a_47b_33-1-jdk21
 docker.io/jenkins/inbound-agent:3355.v388858a_47b_33-1-jdk25