feat(pgsql): add pgsql util playbooks

- start and stop postgres cluster
- start and stop patroni
- patroni pause and resume
- patroni restart (gracefully)

Author: waitingsong

roles/pgsql/tasks/util/check_pg_ready.yml

@@ -0,0 +1,27 @@
+#!/usr/bin/ansible-playbook
+---
+
+- name: check postgres ready
+  tags: check_pg_ready
+  vars:
+    dbsu: "{{ pg_dbsu|default('postgres') }}"
+  block:
+    - name: wait for postgres
+      # when: pg_role == 'primary'
+      wait_for: host={{ inventory_hostname }} port={{ pg_port }} state=started timeout=60
+      ignore_errors: true
+
+    - name: check postgres ready
+      become_user: "{{ dbsu }}"
+      shell: |
+        {{ pg_bin_dir }}/pg_isready -t 5 -p {{ pg_port }}
+      register: result
+      retries: 6
+      until: result.rc == 0
+      delay: 5
+
+    - name: Set fact pg_ready_result
+      set_fact:
+        pg_ready_result: "{{ result }}"
+
+...

roles/pgsql/tasks/util/grace_patroni_restart.yml

@@ -0,0 +1,43 @@
+#!/usr/bin/ansible-playbook
+---
+#--------------------------------------------------------------#
+# patroni restart pg_cls gracefully           [grace_pt_restart]
+# avoiding switching pg primary/standby
+# steps:
+#   1. patroni pause
+#   2. patroni restart pg_cluster
+#   3. patroni resume
+#--------------------------------------------------------------#
+- name: patroni restart pg_cls gracefully
+  tags: grace_pt_restart
+  become_user: "{{ dbsu }}"
+  vars:
+    dbsu: "{{ pg_dbsu|default('postgres') }}"
+  block:
+    - import_tasks: patroni_pause.yml
+
+    - import_tasks: patroni_restart.yml
+      when: patroni_mode != 'remove' and pg_role == 'primary'
+
+    - import_tasks: check_pg_ready.yml
+      when: pg_role == 'primary'
+
+    - import_tasks: patroni_resume.yml
+      when: patroni_mode != 'remove' and pg_role == 'primary'
+
+    # finally, check if all postgres is ready
+    - import_tasks: check_pg_ready.yml
+
+  rescue:
+    - name: check postgres ready failed for {{ pg_cluster }}
+      debug:
+        msg: |
+          rc: {{ pg_ready_result.rc }}
+           STDOUT: {{ pg_ready_result.stdout }}
+           STDERR: {{ pg_ready_result.stderr }}
+      when: pg_ready_result is defined and pg_ready_result.rc != 0
+
+    - name: Exit Playbook due to error
+      meta: end_play
+
+...

roles/pgsql/tasks/util/is_patroni_paused.yml

@@ -0,0 +1,19 @@
+#!/usr/bin/ansible-playbook
+---
+- name: run patroni list
+  become_user: "{{ pg_dbsu|default('postgres') }}"
+  when: patroni_mode != 'remove'
+  args: { executable: /bin/bash }
+  shell: |
+    /usr/bin/patronictl -c /pg/bin/patroni.yml list 2>/dev/null | tail -n 3
+  register: patroni_status_cmd
+  ignore_errors: yes
+  changed_when: false
+
+- name: read patroni maintenance mode
+  when: patroni_mode != 'remove'
+  set_fact:
+    patroni_paused: "{{ patroni_status_cmd.stdout | regex_search('Maintenance mode: on') }}"
+  changed_when: false
+
+...

roles/pgsql/tasks/util/patroni_pause.yml

@@ -0,0 +1,33 @@
+#!/usr/bin/ansible-playbook
+---
+
+- name: patroni pause
+  tags: patroni_pause
+  vars:
+    dbsu: "{{ pg_dbsu|default('postgres') }}"
+  any_errors_fatal: true
+  when: patroni_mode != 'remove'
+  block:
+    - import_tasks: is_patroni_paused.yml
+      when: pg_role == 'primary'
+
+    - name: patroni pause primary {{ pg_cluster }}
+      become_user: "{{ dbsu }}"
+      when: (patroni_paused is not defined or patroni_paused == '') and pg_role == 'primary'
+      command: /usr/bin/patronictl -c /pg/bin/patroni.yml pause
+
+    - name: sleep for patroni paused
+      command: sleep 3
+      when: (patroni_paused is not defined or patroni_paused == '')
+      changed_when: false
+
+    - import_tasks: is_patroni_paused.yml
+      when: pg_role != 'primary'
+
+    - name: patroni pause replica {{ pg_cluster }} (may fail)
+      become_user: "{{ dbsu }}"
+      when: (patroni_paused is not defined or patroni_paused == '') and pg_role != 'primary'
+      command: /usr/bin/patronictl -c /pg/bin/patroni.yml pause
+      ignore_errors: yes
+
+...

roles/pgsql/tasks/util/patroni_restart.yml

@@ -0,0 +1,10 @@
+#!/usr/bin/ansible-playbook
+---
+
+- name: patroni restart {{ pg_cluster }}
+  become_user: "{{ dbsu }}"
+  vars:
+    dbsu: "{{ pg_dbsu|default('postgres') }}"
+  command: /usr/bin/patronictl -c /pg/bin/patroni.yml restart --force {{ pg_cluster }}
+
+...

roles/pgsql/tasks/util/patroni_resume.yml

@@ -0,0 +1,11 @@
+#!/usr/bin/ansible-playbook
+---
+
+- name: patroni resume primary
+  tags: patroni_resume
+  become_user: "{{ dbsu }}"
+  vars:
+    dbsu: "{{ pg_dbsu|default('postgres') }}"
+  command: /usr/bin/patronictl -c /pg/bin/patroni.yml resume
+
+...

roles/pgsql/tasks/util/pg_backup.yml

@@ -0,0 +1,35 @@
+#!/usr/bin/ansible-playbook
+---
+
+- name: pg_backup
+  when: pgbackrest_enabled|bool
+  tags: pg_backup
+  vars:
+    dbsu: "{{ pg_dbsu|default('postgres') }}"
+  block:
+    - name: full backup cls {{ pg_cluster }}
+      become_user: "{{ dbsu }}"
+      when: pg_role == 'primary'
+      command: /pg/bin/pg-backup full
+      register: back_ret_cmd
+      ignore_errors: false
+
+    - name: show backup result for {{ pg_cluster }}
+      when: pg_role == 'primary'
+      debug:
+        msg: |
+          STDOUT {{ back_ret_cmd.stdout_lines }}
+          STDERR {{ back_ret_cmd.stderr_lines }}
+      changed_when: false
+
+  rescue:
+    - name: pg-backup failed for {{ pg_cluster }}
+      debug:
+        msg: |
+          STDOUT: {{ back_ret_cmd.stdout }}
+           STDERR: {{ back_ret_cmd.stderr }}
+      when: back_ret_cmd is defined
+
+    - name: Exit Playbook due to backup failure
+      meta: end_play
+...

roles/pgsql/tasks/util/start_patroni.yml

@@ -0,0 +1,18 @@
+#!/usr/bin/ansible-playbook
+---
+- name: start patroni
+  tags: start_patroni
+  vars:
+    dbsu: "{{ pg_dbsu|default('postgres') }}"
+  block:
+    - name: start patroni
+      when: patroni_mode == 'default'
+      command: systemctl start patroni
+
+    - name: sleep waiting for starting patroni
+      when: patroni_mode == 'default'
+      args: { executable: /bin/bash }
+      shell: sleep 5
+      changed_when: false
+
+...

roles/pgsql/tasks/util/start_pg.yml

@@ -0,0 +1,37 @@
+#!/usr/bin/ansible-playbook
+---
+
+- name: start postgres cluster
+  tags: start_pg
+  vars:
+    dbsu: "{{ pg_dbsu|default('postgres') }}"
+  block:
+    - name: check if postmaster.pid exists and is not empty
+      stat:
+        path: "{{ pg_data }}/postmaster.pid"
+      register: postmaster_pid_stat
+      changed_when: false
+
+    - name: start postgres
+      become_user: "{{ dbsu }}"
+      when: (postmaster_pid_stat.stat.exists == false or postmaster_pid_stat.stat.size == 0)
+      args: { executable: /bin/bash }
+      shell: |
+        {{ pg_bin_dir }}/pg_ctl -D {{ pg_data }} start
+
+    - import_tasks: check_pg_ready.yml
+
+  rescue:
+    - name: check postgres ready failed for {{ pg_cluster }}
+      debug:
+        msg: |
+          rc: {{ pg_ready_result.rc }}
+           STDOUT: {{ pg_ready_result.stdout }}
+           STDERR: {{ pg_ready_result.stderr }}
+      when: pg_ready_result is defined and pg_ready_result.rc != 0
+
+    - name: Exit Playbook due to error
+      meta: end_play
+
+
+...

roles/pgsql/tasks/util/stop_patroni.yml

@@ -0,0 +1,10 @@
+#!/usr/bin/ansible-playbook
+---
+
+- name: stop patroni
+  tags: stop_patroni
+  any_errors_fatal: true
+  when: patroni_mode == 'default'
+  command: systemctl stop patroni
+
+...