Build gerrit images with bazelisk

We need to use bazelisk to build gerrit so that we can properly
track bazel versions in the job. Use the roles developed for
gerrit-review to do that, then simplify the dockerfile to have
it simply copy the war into the target image.

Also add polymer-bridges.

Depends-On: https://review.opendev.org/709256
Change-Id: I7c13df51d3b8c117bcc9aab9caad59687471d622

.zuul.yaml

@@ -200,6 +200,7 @@
     description: Build a gerrit image.
     parent: system-config-build-image
     pre-run: playbooks/zuul/gerrit/repos.yaml
+    run: playbooks/zuul/gerrit/run.yaml
     required-projects: &gerrit_projects_2_15
       - name: gerrit.googlesource.com/gerrit
         override-checkout: stable-2.15
@@ -239,6 +240,7 @@
     description: Build and upload a gerrit image.
     parent: system-config-upload-image
     pre-run: playbooks/zuul/gerrit/repos.yaml
+    run: playbooks/zuul/gerrit/run.yaml
     required-projects: *gerrit_projects_2_15
     vars: *gerrit_vars_2_15
     files: *gerrit_files_2_15
@@ -256,6 +258,7 @@
     description: Build a gerrit image.
     parent: system-config-build-image
     pre-run: playbooks/zuul/gerrit/repos.yaml
+    run: playbooks/zuul/gerrit/run.yaml
     required-projects: &gerrit_projects_2_16
       - name: gerrit.googlesource.com/gerrit
         override-checkout: stable-2.16
@@ -299,6 +302,7 @@
     description: Build and upload a gerrit image.
     parent: system-config-upload-image
     pre-run: playbooks/zuul/gerrit/repos.yaml
+    run: playbooks/zuul/gerrit/run.yaml
     required-projects: *gerrit_projects_2_16
     vars: *gerrit_vars_2_16
     files: *gerrit_files_2_16
@@ -316,6 +320,7 @@
     description: Build a gerrit image.
     parent: system-config-build-image
     pre-run: playbooks/zuul/gerrit/repos.yaml
+    run: playbooks/zuul/gerrit/run.yaml
     required-projects: &gerrit_projects_3_0
       - name: gerrit.googlesource.com/gerrit
         override-checkout: stable-3.0
@@ -371,6 +376,7 @@
     description: Build and upload a gerrit image.
     parent: system-config-upload-image
     pre-run: playbooks/zuul/gerrit/repos.yaml
+    run: playbooks/zuul/gerrit/run.yaml
     required-projects: *gerrit_projects_3_0
     vars: *gerrit_vars_3_0
     files: *gerrit_files_3_0
@@ -392,7 +398,8 @@
     parent: system-config-build-image
     pre-run:
       - playbooks/zuul/gerrit/repos.yaml
-      - playbooks/zuul/gerrit/jgit.yaml
+      - playbooks/zuul/gerrit/submodules.yaml
+    run: playbooks/zuul/gerrit/run.yaml
     required-projects: &gerrit_projects_master
       - opendev/system-config
       - gerrit.googlesource.com/jgit
@@ -412,6 +419,7 @@
       - gerrit.googlesource.com/plugins/reviewnotes
       - gerrit.googlesource.com/plugins/singleusergroup
       - gerrit.googlesource.com/plugins/webhooks
+      - gerrit.googlesource.com/polymer-bridges
     vars: &gerrit_vars_master
       zuul_work_dir: src/opendev.org/opendev/system-config
       docker_images:
@@ -447,7 +455,8 @@
     parent: system-config-upload-image
     pre-run:
       - playbooks/zuul/gerrit/repos.yaml
-      - playbooks/zuul/gerrit/jgit.yaml
+      - playbooks/zuul/gerrit/submodules.yaml
+    run: playbooks/zuul/gerrit/run.yaml
     required-projects: *gerrit_projects_master
     vars: *gerrit_vars_master
     files: *gerrit_files_master

docker/gerrit/bazel/Dockerfile

@@ -13,14 +13,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-FROM docker.io/opendevorg/bazel as builder
-
-USER builder
-COPY . /usr/src
-
-ARG BAZEL_OPTS
-RUN cd /usr/src && bash build-gerrit.sh
-
 FROM docker.io/opendevorg/gerrit-base
 
-COPY --from=builder /usr/src/bazel-bin/release.war /var/gerrit/bin/gerrit.war
+COPY release.war /var/gerrit/bin/gerrit.war

playbooks/zuul/gerrit/jgit.yaml

@@ -1,7 +0,0 @@
-- hosts: all
-  tasks:
-
-    - name: Checkout jgit submodule
-      command: "git submodule update --init modules/jgit"
-      args:
-        chdir: /home/zuul/src/gerrit.googlesource.com/gerrit

playbooks/zuul/gerrit/repos.yaml

@@ -1,5 +1,18 @@
 - hosts: all
+  roles:
+    - ensure-java
+    - role: install-nodejs
+      node_version: 10
+    - ensure-bazelisk
   tasks:
+    - name: Install essential build packages
+      become: true
+      package:
+        name:
+          - build-essential
+          - zip
+          - unzip
+        state: present
 
     - name: Move plugin repos into gerrit tree
       command: "mv -f {{ item }} ../gerrit/plugins"

playbooks/zuul/gerrit/run.yaml

@@ -0,0 +1,9 @@
+- hosts: all
+  roles:
+    - role: bazelisk-build
+      zuul_work_dir: /home/zuul/src/gerrit.googlesource.com/gerrit
+    - build-docker-image
+
+- hosts: localhost
+  roles:
+    - pause-buildset-registry

playbooks/zuul/gerrit/submodules.yaml

@@ -0,0 +1,10 @@
+- hosts: all
+  tasks:
+
+    - name: Checkout submodules
+      shell: "[ -d {{ item }} ] && git submodule update --init {{ item }}"
+      args:
+        chdir: /home/zuul/src/gerrit.googlesource.com/gerrit
+      loop:
+        - modules/jgit
+        - polymer-bridges

roles/bazelisk-build/README.rst

@@ -0,0 +1,26 @@
+Run bazelisk build
+
+Runs bazelisk build with the specified targets.
+
+**Role Variables**
+
+.. zuul:rolevar:: bazelisk_targets
+   :default: ""
+
+   The bazelisk targets to build.
+
+.. zuul:rolevar:: bazelisk_test_targets
+   :default: ""
+
+   The bazelisk targets to test.  ``bazelisk test`` will only be run
+   if this value is not the empty string.
+
+.. zuul:rolevar:: bazelisk_executable
+   :default: bazelisk
+
+   The path to the bazelisk executable.
+
+.. zuul:rolevar:: zuul_work_dir
+   :default: {{ ansible_user_dir }}/{{ zuul.project.src_dir}}
+
+   The working directory in which to run bazelisk.

roles/bazelisk-build/defaults/main.yaml

@@ -0,0 +1,3 @@
+bazelisk_targets: release
+bazelisk_executable: bazelisk
+zuul_work_dir: "{{ ansible_user_dir }}/{{ zuul.project.src_dir}}"

roles/bazelisk-build/tasks/main.yaml

@@ -0,0 +1,10 @@
+- name: Run bazelisk build
+  shell: |
+    java -fullversion
+    {{ bazelisk_executable }} version
+    {{ bazelisk_executable }} build --spawn_strategy=standalone --genrule_strategy=standalone {{ bazelisk_targets }}
+    # release.war is a symlink. We want an actual file so that docker copy works right.
+    cp bazel-bin/release.war release.war
+  args:
+    executable: /bin/bash
+    chdir: "{{ zuul_work_dir }}"