feature: mount - implement swapon/swapoff (#106)

* Declare functions swapon() & swapoff(), is_swap() & reswap().
* Apply swapon/swapoff for states mounted, unmounted, remounted and
  absent.
* Override default opts and boot when fstype=swap.
* Do not honor 'fstab' when fstype=swap (fail instead).
* Also fail when fstype=swap and 'path' is not 'none' ('-' for Solaris).
* Update module documentation accordingly.
+ Replace all platform.system() calls by a variable.

refactor integration tests

* Improve readability/understanding of what is tested, and what OS is
  targeted.
* Move 'swap' related test cases into dedicated file (swap.yml).
* Add new test cases about swap enabling/disabling.
* Extend tests to FreeBSD when possible.

Author: quidame

plugins/modules/mount.py

@@ -0,0 +1,95 @@
+---
+# Tasks to validate bind mounts (i.e. mount of a directory to another one).
+# Linux and FreeBSD only.
+
+- name: Create the mount point (the target of the mount)
+  file:
+    state: directory
+    path: '{{ output_dir }}/mount_dest'
+
+- name: Create a directory to bind mount (the source of the mount)
+  file:
+    state: directory
+    path: '{{ output_dir }}/mount_source'
+
+- name: Put something in the directory so we see that it worked
+  copy:
+    content: 'Testing
+
+      '
+    dest: '{{ output_dir }}/mount_source/test_file'
+  register: orig_info
+
+- name: Bind mount a directory
+  mount:
+    src: '{{ output_dir }}/mount_source'
+    name: '{{ output_dir }}/mount_dest'
+    state: mounted
+    fstype: "{{ 'none' if ansible_system == 'Linux' else 'nullfs' }}"
+    opts:   "{{ 'bind' if ansible_system == 'Linux' else omit }}"
+  register: bind_result
+
+- name: get checksum for bind mounted file
+  stat:
+    path: '{{ output_dir }}/mount_dest/test_file'
+  when: ansible_system in ('FreeBSD', 'Linux')
+  register: dest_stat
+
+- name: assert the bind mount was successful
+  assert:
+    that:
+      - bind_result is changed
+      - dest_stat.stat.exists
+      - orig_info.checksum == dest_stat.stat.checksum
+
+- name: Bind mount a directory again
+  mount:
+    src: '{{ output_dir }}/mount_source'
+    name: '{{ output_dir }}/mount_dest'
+    state: mounted
+    fstype: "{{ 'none' if ansible_system == 'Linux' else 'nullfs' }}"
+    opts:   "{{ 'bind' if ansible_system == 'Linux' else omit }}"
+  register: bind_result
+
+- name: Make sure we didn't mount a second time
+  assert:
+    that:
+      - bind_result is not changed
+
+- name: Remount directory with different options
+  mount:
+    src: '{{ output_dir }}/mount_source'
+    name: '{{ output_dir }}/mount_dest'
+    state: mounted
+    fstype: "{{ 'none' if ansible_system == 'Linux' else 'nullfs' }}"
+    opts:  "{{ 'bind,' if ansible_system == 'Linux' else '' }}ro"
+  register: bind_result
+
+- name: Get mount options
+  shell:
+    cmd: "mount | grep mount_dest | grep -E -w '(ro|read-only)' | wc -l"
+  register: remount_options
+
+- name: Make sure the filesystem now has the new opts
+  assert:
+    that:
+      - bind_result is changed
+      - '''1'' in remount_options.stdout'
+      - 1 == remount_options.stdout_lines | length
+
+- name: Unmount the bind mount
+  mount:
+    name: '{{ output_dir }}/mount_dest'
+    state: absent
+  register: unmount_result
+
+- name: Check if the file still exists in dest
+  stat:
+    path: '{{ output_dir }}/mount_dest/test_file'
+  register: dest_stat
+
+- name: Assert that we unmounted
+  assert:
+    that:
+      - unmount_result is changed
+      - not dest_stat.stat.exists

tests/integration/targets/mount/tasks/bind_mount.yml

@@ -0,0 +1,32 @@
+---
+# Tasks to validate the two last fields in fstab, that are optional on Linux,
+# are added if missing.
+
+- name: Create fstab record with missing last two fields
+  copy:
+    dest: /etc/fstab
+    content: '//nas/photo /home/jik/pictures cifs defaults,credentials=/etc/security/nas.creds,uid=jik,gid=users,forceuid,forcegid,noserverino,_netdev
+
+      '
+
+- name: Try to change the fstab record with the missing last two fields
+  mount:
+    src: //nas/photo
+    path: /home/jik/pictures
+    fstype: cifs
+    opts: defaults,credentials=/etc/security/nas.creds,uid=jik,gid=users,forceuid,forcegid,noserverino,_netdev,x-systemd.mount-timeout=0
+    state: present
+  register: optional_fields_update
+
+- name: Get the content of the fstab file
+  command:
+    cmd: cat /etc/fstab
+  changed_when: false
+  register: optional_fields_content
+
+- name: Check if the line containing the missing last two fields was changed
+  assert:
+    that:
+    - optional_fields_update is changed
+    - ''' 0 0'' in optional_fields_content.stdout'
+    - 1 == optional_fields_content.stdout_lines | length

tests/integration/targets/mount/tasks/fstab_last_fields.yml

@@ -0,0 +1,93 @@
+---
+# Tasks to validate that adding a swap record in fstab doesn't replace another
+# one, unless the 'src' (not the 'path') is the same. For Linux and FreeBSD.
+
+- name: Create fstab record for the first swap device
+  mount:
+    name: none
+    src: /dev/swap1
+    opts: sw
+    fstype: swap
+    state: present
+  register: swap1_created
+
+- name: Try to create fstab record for the first swap device again
+  mount:
+    name: none
+    src: /dev/swap1
+    opts: sw
+    fstype: swap
+    state: present
+  register: swap1_created_again
+
+- name: Check that we created the swap1 record
+  assert:
+    that:
+    - swap1_created is changed
+    - swap1_created_again is not changed
+
+- name: Create fstab record for the second swap device
+  mount:
+    name: none
+    src: /dev/swap2
+    opts: sw
+    fstype: swap
+    state: present
+  register: swap2_created
+
+- name: Try to create fstab record for the second swap device again
+  mount:
+    name: none
+    src: /dev/swap1
+    opts: sw
+    fstype: swap
+    state: present
+  register: swap2_created_again
+
+- name: Check that we created the swap2 record
+  assert:
+    that:
+    - swap2_created is changed
+    - swap2_created_again is not changed
+
+
+
+- name: Remove the fstab record for the first swap device
+  mount:
+    name: none
+    src: /dev/swap1
+    state: absent
+  register: swap1_removed
+
+- name: Try to remove the fstab record for the first swap device again
+  mount:
+    name: none
+    src: /dev/swap1
+    state: absent
+  register: swap1_removed_again
+
+- name: Check that we removed the swap1 record
+  assert:
+    that:
+    - swap1_removed is changed
+    - swap1_removed_again is not changed
+
+- name: Remove the fstab record for the second swap device
+  mount:
+    name: none
+    src: /dev/swap2
+    state: absent
+  register: swap2_removed
+
+- name: Try to remove the fstab record for the second swap device again
+  mount:
+    name: none
+    src: /dev/swap2
+    state: absent
+  register: swap2_removed_again
+
+- name: Check that we removed the swap2 record
+  assert:
+    that:
+    - swap2_removed is changed
+    - swap2_removed_again is not changed