Display DB deprecation notice for PostgreSQL 11

app/controllers/admin/dashboard_controller.rb

@@ -13,6 +13,7 @@ def index
     @users = User.order_id_desc.limit(10)
     @groups = Group.order_id_desc.with_route.limit(10)
     @notices = Gitlab::ConfigChecker::PumaRuggedChecker.check
+    @notices += Gitlab::ConfigChecker::ExternalDatabaseChecker.check
   end
   # rubocop: enable CodeReuse/ActiveRecord
 

changelogs/unreleased/display-db-deprecation-notice.yml

+---
+title: Implement external database checker in dashboard controller
+merge_request: 30389
+author:
+type: deprecated

doc/install/requirements.md

@@ -139,9 +139,12 @@ MySQL/MariaDB are advised to [migrate to PostgreSQL](../update/mysql_to_postgres
 
 ### PostgreSQL Requirements
 
-As of GitLab 10.0, PostgreSQL 9.6 or newer is required, and earlier versions are
-not supported. We highly recommend users to use PostgreSQL 9.6 as this
-is the PostgreSQL version used for development and testing.
+We highly recommend users to use the minimum PostgreSQL versions specified below as these are the versions used for development and testing.
+
+GitLab version | Minimum PostgreSQL version
+-|-
+10.0 | 9.6
+12.10 | 11
 
 Users using PostgreSQL must ensure the `pg_trgm` extension is loaded into every
 GitLab database. This extension can be enabled (using a PostgreSQL super user)

lib/gitlab/config_checker/external_database_checker.rb

+# frozen_string_literal: true
+
+module Gitlab
+  module ConfigChecker
+    module ExternalDatabaseChecker
+      extend self
+
+      # DB is considered deprecated if it is below version 11
+      def db_version_deprecated?
+        Gitlab::Database.version.to_f < 11
+      end
+
+      def check
+        return [] unless db_version_deprecated?
+
+        [
+          {
+            type: 'warning',
+            message: _('Note that PostgreSQL 11 will become the minimum required PostgreSQL version in GitLab 13.0 (May 2020). '\
+                     'PostgreSQL 9.6 and PostgreSQL 10 will no longer be supported in GitLab 13.0. '\
+                     'Please consider upgrading your PostgreSQL version (%{db_version}) soon.') % { db_version: Gitlab::Database.version.to_s }
+          }
+        ]
+      end
+    end
+  end
+end

locale/gitlab.pot

@@ -8,6 +8,8 @@ msgid ""
 msgstr ""
 "Project-Id-Version: gitlab 1.0.0\n"
 "Report-Msgid-Bugs-To: \n"
+"POT-Creation-Date: 2020-04-24 17:33-0400\n"
+"PO-Revision-Date: 2020-04-24 17:33-0400\n"
 "Last-Translator: FULL NAME <EMAIL@ADDRESS>\n"
 "Language-Team: LANGUAGE <LL@li.org>\n"
 "Language: \n"
@@ -14077,6 +14079,9 @@ msgstr ""
 msgid "Note parameters are invalid: %{errors}"
 msgstr ""
+msgid "Note that PostgreSQL 11 will become the minimum required PostgreSQL version in GitLab 13.0 (May 2020). PostgreSQL 9.6 and PostgreSQL 10 will no longer be supported in GitLab 13.0. Please consider upgrading your PostgreSQL version (%{db_version}) soon."
+msgstr ""
+
 msgid "Note that this invitation was sent to %{mail_to_invite_email}, but you are signed in as %{link_to_current_user} with email %{mail_to_current_user}."
 msgstr ""

spec/lib/gitlab/config_checker/external_database_checker_spec.rb

+# frozen_string_literal: true
+
+require 'spec_helper'
+
+describe Gitlab::ConfigChecker::ExternalDatabaseChecker do
+  describe '#check' do
+    subject { described_class.check }
+
+    context 'database version is not deprecated' do
+      before do
+        allow(described_class).to receive(:db_version_deprecated?).and_return(false)
+      end
+
+      it { is_expected.to be_empty }
+    end
+
+    context 'database version is deprecated' do
+      before do
+        allow(described_class).to receive(:db_version_deprecated?).and_return(true)
+      end
+
+      let(:notice_deprecated_database) do
+        {
+          type: 'warning',
+            message: _('Note that PostgreSQL 11 will become the minimum required PostgreSQL version in GitLab 13.0 (May 2020). '\
+                     'PostgreSQL 9.6 and PostgreSQL 10 will no longer be supported in GitLab 13.0. '\
+                     'Please consider upgrading your PostgreSQL version (%{db_version}) soon.') % { db_version: Gitlab::Database.version.to_s }
+        }
+      end
+
+      it 'reports deprecated database notices' do
+        is_expected.to contain_exactly(notice_deprecated_database)
+      end
+    end
+  end
+
+  describe '#db_version_deprecated' do
+    subject { described_class.db_version_deprecated? }
+
+    context 'database version is not deprecated' do
+      before do
+        allow(Gitlab::Database).to receive(:version).and_return(11)
+      end
+
+      it { is_expected.to be false }
+    end
+
+    context 'database version is deprecated' do
+      before do
+        allow(Gitlab::Database).to receive(:version).and_return(10)
+      end
+
+      it { is_expected.to be true }
+    end
+  end
+end