standby-clone: Allow cloning of standby server with pg_basebackup

Right now the role assumes you have a base backup available with
Barman. However if you don't have an initial barman backup you might
want to clone the primary server directly to setup your standby
server.

This PR adds a new `primary.pg_basebackup` option to the cluster
configuration which if enabled (set to `true`) will create a
`/root/standby-clone-{{ postgres_version }}-{{ postgres_cluster_name }}.sh`
script on the standby server which helps to initialise a standby
server.

⚠️ Breaking change: the current role behavior which creates a cloning
script fetching the initial backup from barman will not be
enabled by default anymore. You will need to add the new
`primary.restore_barman_directory` option in your role
configuration to do so. ⚠️

3 files changed, 11 insertions, 3 deletions

diff --git a/tasks/postgres-cluster.yml b/tasks/postgres-cluster.yml
index a8e96c1..4f62d31 100644
--- a/tasks/postgres-cluster.yml
+++ b/tasks/postgres-cluster.yml
@@ -60,7 +60,11 @@
 
 - name: Add standby clone from barman script
   include: postgres-standby-barman.yml
-  when: postgres_barman_server is defined
+  when: postgres_barman_server is defined and postgres_primary.restore_barman_directory is defined
+
+- name: Add standby clone from pg_basebackup
+  include: postgres-standby-basebackup.yml
+  when: postgres_primary and postgres_primary.pg_basebackup is defined
 
 - name: Determine SSD or rotational disks
   raw: 'lsblk --noheadings --nodeps --raw --output=rota | grep -q 1'
diff --git a/tasks/postgres-standby-barman.yml b/tasks/postgres-standby-barman.yml
index 6a94b75..fb71d32 100644
--- a/tasks/postgres-standby-barman.yml
+++ b/tasks/postgres-standby-barman.yml
@@ -11,8 +11,8 @@
     path: "{{ postgres_barman_path_prefix | default('~') }}"
     rsync_password_file: "{{ postgres_barman_rsync_enabled | ternary(' --password-file=/var/lib/postgresql/.rsync_pass ', '') }}"
 
-- name: Copy secondary script
-  template: src=standby-clone.sh.j2 dest=/root/standby-clone-{{ postgres_version }}-{{ postgres_cluster_name }}.sh mode=0755
+- name: Copy secondary barman clone script
+  template: src=standby-barman-clone.sh.j2 dest=/root/standby-clone-{{ postgres_version }}-{{ postgres_cluster_name }}.sh mode=0755
 
 - name: Copy rsync password file
   copy:
diff --git a/tasks/postgres-standby-basebackup.yml b/tasks/postgres-standby-basebackup.yml
new file mode 100644
index 0000000..db52d55
--- /dev/null
+++ b/tasks/postgres-standby-basebackup.yml
@@ -0,0 +1,4 @@
+---
+- name: Copy secondary pg_basebackup clone script
+  template: src=standby-pg_basebackup-clone.sh.j2 dest=/root/standby-clone-{{ postgres_version }}-{{ postgres_cluster_name }}.sh mode=0755
+  no_log: true