Test against PG9 by default, PG11 in master, and PG10 nightly

Align MR testing strategy with current GitLab.com to ensure
availability for changes of GitLab.com.
Signed-off-by: Rémy Coutable <remy@rymai.me>

.gitlab-ci.yml

-image: "registry.gitlab.com/gitlab-org/gitlab-build-images:ruby-2.6.5-golang-1.14-git-2.26-lfs-2.9-chrome-73.0-node-12.x-yarn-1.21-postgresql-10-graphicsmagick-1.3.34"
-
 stages:
   - sync
   - prepare
@@ -16,6 +14,7 @@ stages:
 # in cases where jobs require Docker-in-Docker, the job
 # definition must be extended with `.use-docker-in-docker`
 default:
+  image: "registry.gitlab.com/gitlab-org/gitlab-build-images:ruby-2.6.5-golang-1.14-git-2.26-lfs-2.9-chrome-73.0-node-12.x-yarn-1.21-postgresql-9.6-graphicsmagick-1.3.34"
   tags:
     - gitlab-org
   # All jobs are interruptible by default

.gitlab/ci/dev-fixtures.gitlab-ci.yml

@@ -3,9 +3,9 @@
     - .default-retry
     - .default-cache
     - .default-before_script
-    - .use-pg11
+    - .use-pg9
   stage: test
-  needs: ["setup-test-env pg11"]
+  needs: ["setup-test-env pg9"]
   variables:
     FIXTURE_PATH: "db/fixtures/development"
     SEED_CYCLE_ANALYTICS: "true"
@@ -26,7 +26,7 @@ run-dev-fixtures-ee:
   extends:
     - .run-dev-fixtures
     - .dev-fixtures:rules:ee-only
-    - .use-pg11-ee
+    - .use-pg9-ee
   script:
     - scripts/gitaly-test-spawn
     - cp ee/db/fixtures/development/* $FIXTURE_PATH

.gitlab/ci/docs.gitlab-ci.yml

@@ -66,9 +66,9 @@ graphql-reference-verify:
     - .default-cache
     - .default-before_script
     - .docs:rules:graphql-reference-verify
-    - .use-pg11
+    - .use-pg9
   stage: test
-  needs: ["setup-test-env pg11"]
+  needs: ["setup-test-env pg9"]
   script:
     - bundle exec rake gitlab:graphql:check_docs
     - bundle exec rake gitlab:graphql:check_schema

.gitlab/ci/frontend.gitlab-ci.yml

@@ -129,9 +129,9 @@ compile-assets pull-cache as-if-foss:
     - .default-retry
     - .default-cache
     - .default-before_script
-    - .use-pg11
+    - .use-pg9
   stage: fixtures
-  needs: ["setup-test-env pg11", "compile-assets pull-cache"]
+  needs: ["setup-test-env pg9", "compile-assets pull-cache"]
   script:
     - date
     - scripts/gitaly-test-spawn

.gitlab/ci/memory.gitlab-ci.yml

@@ -8,7 +8,7 @@
 memory-static:
   extends: .only-code-memory-job-base
   stage: test
-  needs: ["setup-test-env pg11"]
+  needs: ["setup-test-env pg9"]
   variables:
     SETUP_DB: "false"
   script:
@@ -36,9 +36,9 @@ memory-static:
 memory-on-boot:
   extends:
     - .only-code-memory-job-base
-    - .use-pg11
+    - .use-pg9
   stage: test
-  needs: ["setup-test-env pg11", "compile-assets pull-cache"]
+  needs: ["setup-test-env pg9", "compile-assets pull-cache"]
   variables:
     NODE_ENV: "production"
     RAILS_ENV: "production"

.gitlab/ci/rules.gitlab-ci.yml

@@ -16,6 +16,15 @@
 .if-master-refs: &if-master-refs
   if: '$CI_COMMIT_REF_NAME == "master"'
 
+.if-master-push: &if-master-push
+  if: '$CI_COMMIT_BRANCH == "master" && $CI_PIPELINE_SOURCE == "push"'
+
+.if-master-schedule-2-hourly: &if-master-schedule-2-hourly
+  if: '$CI_COMMIT_BRANCH == "master" && $CI_PIPELINE_SOURCE == "schedule" && $FREQUENCY == "2-hourly"'
+
+.if-master-schedule-nightly: &if-master-schedule-nightly
+  if: '$CI_COMMIT_BRANCH == "master" && $CI_PIPELINE_SOURCE == "schedule" && $FREQUENCY == "nightly"'
+
 .if-auto-deploy-branches: &if-auto-deploy-branches
   if: '$CI_COMMIT_BRANCH =~ /^\d+-\d+-auto-deploy-\d+$/'
 
@@ -25,9 +34,6 @@
 .if-merge-request: &if-merge-request
   if: '$CI_MERGE_REQUEST_IID'
 
-.if-nightly-master-schedule: &if-nightly-master-schedule
-  if: '$NIGHTLY && $CI_COMMIT_REF_NAME == "master" && $CI_PIPELINE_SOURCE == "schedule"'
-
 .if-dot-com-gitlab-org-schedule: &if-dot-com-gitlab-org-schedule
   if: '$CI_SERVER_HOST == "gitlab.com" && $CI_PROJECT_NAMESPACE == "gitlab-org" && $CI_PIPELINE_SOURCE == "schedule"'
 
@@ -348,36 +354,33 @@
   rules:
     - <<: *if-default-refs
       changes: *code-backstage-patterns
-      when: on_success
 
 .rails:rules:default-refs-code-backstage-qa:
   rules:
     - <<: *if-default-refs
       changes: *code-backstage-qa-patterns
-      when: on_success
 
-.rails:rules:master-refs-code-backstage:
+.rails:rules:master-push--master-schedule-2-hourly--code-backstage:
   rules:
-    - <<: *if-master-refs
+    - <<: *if-master-push
       changes: *code-backstage-patterns
-      when: on_success
-    - changes: [".gitlab/ci/rails.gitlab-ci.yml"]
+    - <<: *if-master-schedule-2-hourly
+    - <<: *if-merge-request
+      changes: [".gitlab/ci/rails.gitlab-ci.yml"]
 
-.rails:rules:nightly-master-refs-code-backstage:
+.rails:rules:master-schedule-nightly--code-backstage:
   rules:
-    - <<: *if-nightly-master-schedule
-      changes: *code-backstage-patterns
-      when: on_success
-    - changes: [".gitlab/ci/rails.gitlab-ci.yml"]
+    - <<: *if-master-schedule-nightly
+    - <<: *if-merge-request
+      changes: [".gitlab/ci/rails.gitlab-ci.yml"]
 
-.rails:rules:nightly-master-refs-code-backstage-ee-only:
+.rails:rules:master-schedule-nightly--code-backstage-ee-only:
   rules:
     - <<: *if-not-ee
       when: never
-    - <<: *if-nightly-master-schedule
-      changes: *code-backstage-patterns
-      when: on_success
-    - changes: [".gitlab/ci/rails.gitlab-ci.yml"]
+    - <<: *if-master-schedule-nightly
+    - <<: *if-merge-request
+      changes: [".gitlab/ci/rails.gitlab-ci.yml"]
 
 .rails:rules:ee-only:
   rules:
@@ -385,13 +388,11 @@
       when: never
     - <<: *if-default-refs
       changes: *code-backstage-patterns
-      when: on_success
 
 .rails:rules:downtime_check:
   rules:
     - <<: *if-merge-request
       changes: *code-backstage-patterns
-      when: on_success
 
 ##################
 # Releases rules #

.gitlab/ci/setup.gitlab-ci.yml

@@ -7,7 +7,7 @@ cache gems:
     - .default-before_script
     - .setup:rules:cache-gems
   stage: test
-  needs: ["setup-test-env pg11"]
+  needs: ["setup-test-env pg9"]
   variables:
     SETUP_DB: "false"
   script:

.gitlab/ci/test-metadata.gitlab-ci.yml

@@ -32,18 +32,18 @@ update-tests-metadata:
     - .test-metadata:rules:update-tests-metadata
   stage: post-test
   dependencies:
-    - setup-test-env pg11
-    - rspec migration pg11
-    - rspec unit pg11
-    - rspec integration pg11
-    - rspec system pg11
-    - rspec-ee migration pg11
-    - rspec-ee unit pg11
-    - rspec-ee integration pg11
-    - rspec-ee system pg11
-    - rspec-ee unit pg11 geo
-    - rspec-ee integration pg11 geo
-    - rspec-ee system pg11 geo
+    - setup-test-env pg9
+    - rspec migration pg9
+    - rspec unit pg9
+    - rspec integration pg9
+    - rspec system pg9
+    - rspec-ee migration pg9
+    - rspec-ee unit pg9
+    - rspec-ee integration pg9
+    - rspec-ee system pg9
+    - rspec-ee unit pg9 geo
+    - rspec-ee integration pg9 geo
+    - rspec-ee system pg9 geo
   cache:
     policy: push
   script:

doc/development/pipelines.md

@@ -151,15 +151,26 @@ request, be sure to start the `dont-interrupt-me` job before pushing.
 
 ## PostgreSQL versions testing
 
+### Current versions testing
+
+| Where? | PG version |
+| ------ | ------ |
+| MRs | 9.6 |
+| `master` (non-scheduled pipelines) | 9.6 / 11 |
+| 2-hourly scheduled pipelines | 9.6 / 11 |
+| Nightly scheduled pipeline | 9.6 / 10 |
+
+### Long-term plan
+
 We follow the [PostgreSQL versions shipped with Omnibus GitLab](https://docs.gitlab.com/omnibus/package-information/postgresql_versions.html):
 
-|        | 12.10 (April 2020) | 13.0 (May 2020) | 13.1 (June 2020) | 13.2 (July 2020) | 13.3 (August 2020) | 13.4, 13.5   | 13.6 (November 2020) | 14.0 (May 2021?) |
+| PG version | 12.10 (April 2020) | 13.0 (May 2020) | 13.1 (June 2020) | 13.2 (July 2020) | 13.3 (August 2020) | 13.4, 13.5   | 13.6 (November 2020) | 14.0 (May 2021?) |
 | ------ | ------------------ | --------------- | ---------------- | ---------------- | ------------------ | ------------ | -------------------- | ---------------- |
-| PG9.6  | nightly            | -               | -                | -                | -                  | -            | -                    | -                |
-| PG10   | `master`           | -               | -                | -                | -                  | -            | -                    | -                |
-| PG11   | MRs/`master`       | MRs/`master`    | MRs/`master`     | MRs/`master`     | MRs/`master`       | MRs/`master` | nightly              | -                |
-| PG12   | -                  | -               | -                | -                | `master`           | `master`     | MRs/`master`         | `master`         |
-| PG13   | -                  | -               | -                | -                | -                  | -            | -                    | MRs/`master`     |
+| PG9.6  | MRs/`master`/`2-hour`/`nightly` | -               | -                | -                | -                  | -            | -                    | -                |
+| PG10   | `nightly`           | -               | -                | -                | -                  | -            | -                    | -                |
+| PG11   | `master`/`2-hour` | MRs/`master`/`2-hour`/`nightly` | MRs/`master`/`2-hour`/`nightly` | MRs/`master`/`2-hour`/`nightly` | MRs/`master`/`2-hour`/`nightly` | MRs/`master`/`2-hour`/`nightly` | `nightly`              | -                |
+| PG12   | -                  | -               | -                | -                | `master`/`2-hour` | `master`/`2-hour` | MRs/`master`/`2-hour`/`nightly`         | `master`/`2-hour` |
+| PG13   | -                  | -               | -                | -                | -                  | -            | -                    | MRs/`master`/`2-hour`/`nightly`     |
 
 ## Pipeline types