Filesystem: refactor, improvements, add tests (#25519)

* filesystem: list used tools

* filesystem: btrfs and reiserfs don't support resizing

* filesystem: list supported filesystems

use formatting functions and 'filesystem' instead of 'file system'

* filesystem: PEP8

* filesystem: remove useless calls to module.boolean

* filesystem: fail when the requested action isn't implemented

* filesystem: resizefs: list supported FS rather than unsupported

* filesystem: refactor

* filesystem: add integration tests

* filesystem: allow to use image file with 'dev' param

* filesystem: test resizefs (ext2/3/4 filesystems only)

* filesystem: Btrfs, handle older version than v0.20-rc1

* filesystem: use loop keyword (integration tests)

* filesystem: new test, check when another filesystem already exists

* filesystem: add myself as a maintainer

* filesystem: fix tests as filters

.github/BOTMETA.yml

@@ -627,7 +627,7 @@ files:
   $modules/system/dconf.py: azaghal
   $modules/system/debconf.py: bcoca
   $modules/system/facter.py: $team_ansible
-  $modules/system/filesystem.py: abulimov
+  $modules/system/filesystem.py: abulimov pilou-
   $modules/system/firewalld.py: maxamillion
   $modules/system/gconftool2.py: akasurde kevensen
   $modules/system/getent.py: bcoca

lib/ansible/modules/system/filesystem.py

@@ -16,21 +16,22 @@ DOCUMENTATION = '''
 author:
 - Alexander Bulimov (@abulimov)
 module: filesystem
-short_description: Makes file system on block device
+short_description: Makes a filesystem
 description:
-  - This module creates file system.
+  - This module creates a filesystem.
 version_added: "1.2"
 options:
   fstype:
     choices: [ btrfs, ext2, ext3, ext4, ext4dev, lvm, reiserfs, xfs ]
     description:
-    - File System type to be created.
+    - Filesystem type to be created.
     - reiserfs support was added in 2.2.
     - lvm support was added in 2.5.
+    - since 2.5, I(dev) can be an image file.
     required: yes
   dev:
     description:
-    - Target block device.
+    - Target path to device or image file.
     required: yes
   force:
     description:
@@ -39,16 +40,20 @@ options:
     default: 'no'
   resizefs:
     description:
-    - If C(yes), if the block device and filessytem size differ, grow the filesystem into the space.
+    - If C(yes), if the block device and filesytem size differ, grow the filesystem into the space.
-    - Note, XFS Will only grow if mounted.
+    - Supported for C(ext2), C(ext3), C(ext4), C(ext4dev), C(lvm) and C(xfs) filesystems.
+    - XFS Will only grow if mounted.
     type: bool
     default: 'no'
     version_added: "2.0"
   opts:
     description:
     - List of options to be passed to mkfs command.
+requirements:
+  - Uses tools related to the I(fstype) (C(mkfs)) and C(blkid) command. When I(resizefs) is enabled, C(blockdev) command is required too.
 notes:
-  - Uses mkfs command.
+  - Potential filesystem on I(dev) are checked using C(blkid), in case C(blkid) isn't able to detect an existing filesystem,
+    this filesystem is overwritten even if I(force) is C(no).
 '''
 
 EXAMPLES = '''
@@ -64,63 +69,174 @@ EXAMPLES = '''
     opts: -cc
 '''
 
+from distutils.version import LooseVersion
 import os
+import re
+import stat
 
 from ansible.module_utils.basic import AnsibleModule
+from ansible.module_utils.six import viewkeys
 
 
-def _get_dev_size(dev, module):
+class Filesystem(object):
-    """ Return size in bytes of device. Returns int """
+
-    blockdev_cmd = module.get_bin_path("blockdev", required=True)
+    GROW = None
-    rc, devsize_in_bytes, err = module.run_command("%s %s %s" % (blockdev_cmd, "--getsize64", dev))
+    MKFS = None
-    return int(devsize_in_bytes)
+    MKFS_FORCE_FLAGS = ''
+
+    def __init__(self, module):
+        self.module = module
+
+    @property
+    def fstype(self):
+        return type(self).__name__
+
+    def get_dev_size(self, dev):
+        """ Return size in bytes of device. Returns int """
+        blockdev_cmd = self.module.get_bin_path("blockdev", required=True)
+        _, devsize_in_bytes, _ = self.module.run_command("%s %s %s" % (blockdev_cmd, "--getsize64", dev), check_rc=True)
+        return int(devsize_in_bytes)
+
+    def get_fs_size(self, dev):
+        """ Return size in bytes of filesystem on device. Returns int """
+        raise NotImplementedError()
+
+    def create(self, opts, dev):
+        if self.module.check_mode:
+            return
+
+        mkfs = self.module.get_bin_path(self.MKFS, required=True)
+        if opts is None:
+            cmd = "%s %s '%s'" % (mkfs, self.MKFS_FORCE_FLAGS, dev)
+        else:
+            cmd = "%s %s %s '%s'" % (mkfs, self.MKFS_FORCE_FLAGS, opts, dev)
+        self.module.run_command(cmd, check_rc=True)
+
+    def grow(self, dev):
+        """Get dev and fs size and compare. Returns stdout of used command."""
+        statinfo = os.stat(dev)
+        if stat.S_ISBLK(statinfo.st_mode):
+            devsize_in_bytes = self.get_dev_size(dev)
+        elif os.path.isfile(dev):
+            devsize_in_bytes = os.path.getsize(dev)
+        else:
+            self.module.fail_json(changed=False, msg="Target device not supported: %r." % dev)
+
+        try:
+            fssize_in_bytes = self.get_fs_size(dev)
+        except NotImplementedError:
+            self.module.fail_json(changed=False, msg="module does not support resizing %s filesystem yet." % self.fstype)
+        fs_smaller = fssize_in_bytes < devsize_in_bytes
+
+        if self.module.check_mode and fs_smaller:
+            self.module.exit_json(changed=True, msg="Resizing filesystem %s on device %s" % (self.fstype, dev))
+        elif self.module.check_mode and not fs_smaller:
+            self.module.exit_json(changed=False, msg="%s filesystem is using the whole device %s" % (self.fstype, dev))
+        elif fs_smaller:
+            cmd = self.module.get_bin_path(self.GROW, required=True)
+            _, out, _ = self.module.run_command("%s %s" % (cmd, dev), check_rc=True)
+            return out
+        else:
+            self.module.exit_json(changed=False, msg="%s filesystem is using the whole device %s" % (self.fstype, dev))
 
 
-def _get_fs_size(fssize_cmd, dev, module):
+class Ext(Filesystem):
-    """ Return size in bytes of filesystem on device. Returns int """
+    MKFS_FORCE_FLAGS = '-F'
-    cmd = module.get_bin_path(fssize_cmd, required=True)
+    GROW = 'resize2fs'
-    if 'tune2fs' == fssize_cmd:
+
+    def get_fs_size(self, dev):
+        cmd = self.module.get_bin_path('tune2fs', required=True)
         # Get Block count and Block size
-        rc, size, err = module.run_command("%s %s %s" % (cmd, '-l', dev))
+        _, size, _ = self.module.run_command([cmd, '-l', dev], check_rc=True)
-        if rc == 0:
+        for line in size.splitlines():
-            for line in size.splitlines():
+            if 'Block count:' in line:
-                if 'Block count:' in line:
+                block_count = int(line.split(':')[1].strip())
-                    block_count = int(line.split(':')[1].strip())
+            elif 'Block size:' in line:
-                elif 'Block size:' in line:
+                block_size = int(line.split(':')[1].strip())
-                    block_size = int(line.split(':')[1].strip())
+                return block_size * block_count
-                    break
-        else:
-            module.fail_json(msg="Failed to get block count and block size of %s with %s" % (dev, cmd), rc=rc, err=err)
-    elif 'xfs_growfs' == fssize_cmd:
-        # Get Block count and Block size
-        rc, size, err = module.run_command([cmd, '-n', dev])
-        if rc == 0:
-            for line in size.splitlines():
-                col = line.split('=')
-                if col[0].strip() == 'data':
-                    if col[1].strip() != 'bsize':
-                        module.fail_json(msg='Unexpected output format from xfs_growfs (could not locate "bsize")')
-                    if col[2].split()[1] != 'blocks':
-                        module.fail_json(msg='Unexpected output format from xfs_growfs (could not locate "blocks")')
-                    block_size = int(col[2].split()[0])
-                    block_count = int(col[3].split(',')[0])
-                    break
-        else:
-            module.fail_json(msg="Failed to get block count and block size of %s with %s" % (dev, cmd), rc=rc, err=err)
-    elif 'btrfs' == fssize_cmd:
-        # ToDo
-        # There is no way to get the blocksize and blockcount for btrfs filesystems
-        block_size = 1
-        block_count = 1
-    elif 'pvs' == fssize_cmd:
-        rc, size, err = module.run_command([cmd, '--noheadings', '-o', 'pv_size', '--units', 'b', dev])
-        if rc == 0:
-            block_count = int(size[:-1])
-            block_size = 1
-        else:
-            module.fail_json(msg="Failed to get block count and block size of %s with %s" % (dev, cmd), rc=rc, err=err)
 
-    return block_size * block_count
+
+class Ext2(Ext):
+    MKFS = 'mkfs.ext2'
+
+
+class Ext3(Ext):
+    MKFS = 'mkfs.ext3'
+
+
+class Ext4(Ext):
+    MKFS = 'mkfs.ext4'
+
+
+class XFS(Filesystem):
+    MKFS = 'mkfs.xfs'
+    MKFS_FORCE_FLAGS = '-f'
+    GROW = 'xfs_growfs'
+
+    def get_fs_size(self, dev):
+        cmd = self.module.get_bin_path('xfs_growfs', required=True)
+        _, size, _ = self.module.run_command([cmd, '-n', dev], check_rc=True)
+        for line in size.splitlines():
+            col = line.split('=')
+            if col[0].strip() == 'data':
+                if col[1].strip() != 'bsize':
+                    self.module.fail_json(msg='Unexpected output format from xfs_growfs (could not locate "bsize")')
+                if col[2].split()[1] != 'blocks':
+                    self.module.fail_json(msg='Unexpected output format from xfs_growfs (could not locate "blocks")')
+                block_size = int(col[2].split()[0])
+                block_count = int(col[3].split(',')[0])
+                return block_size * block_count
+
+
+class Reiserfs(Filesystem):
+    MKFS = 'mkfs.reiserfs'
+    MKFS_FORCE_FLAGS = '-f'
+
+
+class Btrfs(Filesystem):
+    MKFS = 'mkfs.btrfs'
+
+    def __init__(self, module):
+        super(Btrfs, self).__init__(module)
+        _, stdout, stderr = self.module.run_command('%s --version' % self.MKFS, check_rc=True)
+        match = re.search(r" v([0-9.]+)", stdout)
+        if not match:
+            # v0.20-rc1 use stderr
+            match = re.search(r" v([0-9.]+)", stderr)
+        if match:
+            # v0.20-rc1 doesn't have --force parameter added in following version v3.12
+            if LooseVersion(match.group(1)) >= LooseVersion('3.12'):
+                self.MKFS_FORCE_FLAGS = '-f'
+            else:
+                self.MKFS_FORCE_FLAGS = ''
+        else:
+            # assume version is greater or equal to 3.12
+            self.MKFS_FORCE_FLAGS = '-f'
+            self.module.warn('Unable to identify mkfs.btrfs version (%r, %r)' % (stdout, stderr))
+
+
+class LVM(Filesystem):
+    MKFS = 'pvcreate'
+    MKFS_FORCE_FLAGS = '-f'
+    GROW = 'pvresize'
+
+    def get_fs_size(self, dev):
+        cmd = self.module.get_bin_path('pvs', required=True)
+        _, size, _ = self.module.run_command([cmd, '--noheadings', '-o', 'pv_size', '--units', 'b', dev], check_rc=True)
+        block_count = int(size[:-1])  # block size is 1
+        return block_count
+
+
+FILESYSTEMS = {
+    'ext2': Ext2,
+    'ext3': Ext3,
+    'ext4': Ext4,
+    'ext4dev': Ext4,
+    'reiserfs': Reiserfs,
+    'xfs': XFS,
+    'btrfs': Btrfs,
+    'LVM2_member': LVM,
+}
 
 
 def main():
@@ -129,71 +245,12 @@ def main():
     }
 
     # There is no "single command" to manipulate filesystems, so we map them all out and their options
-    fs_cmd_map = {
-        'ext2': {
-            'mkfs': 'mkfs.ext2',
-            'grow': 'resize2fs',
-            'grow_flag': None,
-            'force_flag': '-F',
-            'fsinfo': 'tune2fs',
-        },
-        'ext3': {
-            'mkfs': 'mkfs.ext3',
-            'grow': 'resize2fs',
-            'grow_flag': None,
-            'force_flag': '-F',
-            'fsinfo': 'tune2fs',
-        },
-        'ext4': {
-            'mkfs': 'mkfs.ext4',
-            'grow': 'resize2fs',
-            'grow_flag': None,
-            'force_flag': '-F',
-            'fsinfo': 'tune2fs',
-        },
-        'reiserfs': {
-            'mkfs': 'mkfs.reiserfs',
-            'grow': 'resize_reiserfs',
-            'grow_flag': None,
-            'force_flag': '-f',
-            'fsinfo': 'reiserfstune',
-        },
-        'ext4dev': {
-            'mkfs': 'mkfs.ext4',
-            'grow': 'resize2fs',
-            'grow_flag': None,
-            'force_flag': '-F',
-            'fsinfo': 'tune2fs',
-        },
-        'xfs': {
-            'mkfs': 'mkfs.xfs',
-            'grow': 'xfs_growfs',
-            'grow_flag': None,
-            'force_flag': '-f',
-            'fsinfo': 'xfs_growfs',
-        },
-        'btrfs': {
-            'mkfs': 'mkfs.btrfs',
-            'grow': 'btrfs',
-            'grow_flag': 'filesystem resize',
-            'force_flag': '-f',
-            'fsinfo': 'btrfs',
-        },
-        'LVM2_member': {
-            'mkfs': 'pvcreate',
-            'grow': 'pvresize',
-            'grow_flag': None,
-            'force_flag': '-f',
-            'fsinfo': 'pvs',
-        }
-    }
-
     module = AnsibleModule(
         argument_spec=dict(
-            fstype=dict(type='str', required=True, aliases=['type'],
+            fstype=dict(required=True, aliases=['type'],
-                        choices=fs_cmd_map.keys() + friendly_names.keys()),
+                        choices=list(FILESYSTEMS.keys()) + list(friendly_names.keys())),
-            dev=dict(type='str', required=True, aliases=['device']),
+            dev=dict(required=True, aliases=['device']),
-            opts=dict(type='str'),
+            opts=dict(),
             force=dict(type='bool', default=False),
             resizefs=dict(type='bool', default=False),
         ),
@@ -203,8 +260,8 @@ def main():
     dev = module.params['dev']
     fstype = module.params['fstype']
     opts = module.params['opts']
-    force = module.boolean(module.params['force'])
+    force = module.params['force']
-    resizefs = module.boolean(module.params['resizefs'])
+    resizefs = module.params['resizefs']
 
     if fstype in friendly_names:
         fstype = friendly_names[fstype]
@@ -212,70 +269,39 @@ def main():
     changed = False
 
     try:
-        _ = fs_cmd_map[fstype]
+        klass = FILESYSTEMS[fstype]
     except KeyError:
-        module.exit_json(changed=False, msg="WARNING: module does not support this filesystem yet. %s" % fstype)
+        module.fail_json(changed=False, msg="module does not support this filesystem (%s) yet." % fstype)
-
-    mkfscmd = fs_cmd_map[fstype]['mkfs']
-    force_flag = fs_cmd_map[fstype]['force_flag']
-    growcmd = fs_cmd_map[fstype]['grow']
-    fssize_cmd = fs_cmd_map[fstype]['fsinfo']
 
     if not os.path.exists(dev):
         module.fail_json(msg="Device %s not found." % dev)
 
     cmd = module.get_bin_path('blkid', required=True)
-
     rc, raw_fs, err = module.run_command("%s -c /dev/null -o value -s TYPE %s" % (cmd, dev))
+    # In case blkid isn't able to identify an existing filesystem, device is considered as empty,
+    # then this existing filesystem would be overwritten even if force isn't enabled.
     fs = raw_fs.strip()
 
-    if fs == fstype and resizefs is False and not force:
+    filesystem = klass(module)
-        module.exit_json(changed=False)
-    elif fs == fstype and resizefs is True:
-        # Get dev and fs size and compare
-        devsize_in_bytes = _get_dev_size(dev, module)
-        fssize_in_bytes = _get_fs_size(fssize_cmd, dev, module)
-        if fssize_in_bytes < devsize_in_bytes:
-            fs_smaller = True
-        else:
-            fs_smaller = False
 
-        if module.check_mode and fs_smaller:
+    same_fs = fs and FILESYSTEMS.get(fs) == FILESYSTEMS[fstype]
-            module.exit_json(changed=True, msg="Resizing filesystem %s on device %s" % (fstype, dev))
+    if same_fs and not resizefs and not force:
-        elif module.check_mode and not fs_smaller:
+        module.exit_json(changed=False)
-            module.exit_json(changed=False, msg="%s filesystem is using the whole device %s" % (fstype, dev))
+    elif same_fs and resizefs:
-        elif fs_smaller:
+        if not filesystem.GROW:
-            cmd = module.get_bin_path(growcmd, required=True)
+            module.fail_json(changed=False, msg="module does not support resizing %s filesystem yet." % fstype)
-            rc, out, err = module.run_command("%s %s" % (cmd, dev))
+
-            # Sadly there is no easy way to determine if this has changed. For now, just say "true" and move on.
+        out = filesystem.grow(dev)
-            #  in the future, you would have to parse the output to determine this.
+        # Sadly there is no easy way to determine if this has changed. For now, just say "true" and move on.
-            #  thankfully, these are safe operations if no change is made.
+        #  in the future, you would have to parse the output to determine this.
-            if rc == 0:
+        #  thankfully, these are safe operations if no change is made.
-                module.exit_json(changed=True, msg=out)
+        module.exit_json(changed=True, msg=out)
-            else:
-                module.fail_json(msg="Resizing filesystem %s on device '%s' failed" % (fstype, dev), rc=rc, err=err)
-        else:
-            module.exit_json(changed=False, msg="%s filesystem is using the whole device %s" % (fstype, dev))
     elif fs and not force:
         module.fail_json(msg="'%s' is already used as %s, use force=yes to overwrite" % (dev, fs), rc=rc, err=err)
 
     # create fs
-
+    filesystem.create(opts, dev)
-    if module.check_mode:
+    changed = True
-        changed = True
-    else:
-        mkfs = module.get_bin_path(mkfscmd, required=True)
-        cmd = None
-
-        if opts is None:
-            cmd = "%s %s '%s'" % (mkfs, force_flag, dev)
-        else:
-            cmd = "%s %s %s '%s'" % (mkfs, force_flag, opts, dev)
-        rc, _, err = module.run_command(cmd)
-        if rc == 0:
-            changed = True
-        else:
-            module.fail_json(msg="Creating filesystem %s on device '%s' failed" % (fstype, dev), rc=rc, err=err)
 
     module.exit_json(changed=changed)
 

test/integration/targets/filesystem/aliases

@@ -0,0 +1,3 @@
+destructive
+posix/ci/group3
+skip/osx

test/integration/targets/filesystem/defaults/main.yml

@@ -0,0 +1,14 @@
+tested_filesystems:
+  # key: fstype
+  #   fssize: size (Mo)
+  #   grow: True if resizefs is supported
+  # Other minimal sizes:
+  # - XFS: 20Mo
+  # - Btrfs: 100Mo (50Mo when "--metadata single" is used)
+  ext4: {fssize: 10, grow: True}
+  ext4dev: {fssize: 10, grow: True}
+  ext3: {fssize: 10, grow: True}
+  ext2: {fssize: 10, grow: True}
+  xfs: {fssize: 20, grow: False}  # grow requires a mounted filesystem
+  btrfs: {fssize: 100, grow: False}  # grow not implemented
+  # untested: lvm, requires a block device

test/integration/targets/filesystem/tasks/create_fs.yml

@@ -0,0 +1,88 @@
+- block:
+  - name: 'Create a "disk" file'
+    command: 'dd if=/dev/zero of={{ dev }} bs=1M count={{ fssize }}'
+
+  - name: filesystem creation
+    filesystem:
+      dev: '{{ dev }}'
+      fstype: '{{ fstype }}'
+    register: fs_result
+
+  - assert:
+      that:
+        - 'fs_result is changed'
+        - 'fs_result is success'
+
+  - command: 'blkid -c /dev/null -o value -s UUID {{ dev }}'
+    register: uuid
+
+  - name: "Check that filesystem isn't created if force isn't used"
+    filesystem:
+      dev: '{{ dev }}'
+      fstype: '{{ fstype }}'
+    register: fs2_result
+
+  - command: 'blkid -c /dev/null -o value -s UUID {{ dev }}'
+    register: uuid2
+
+  - assert:
+      that:
+        - 'not (fs2_result is changed)'
+        - 'fs2_result is success'
+        - 'uuid.stdout == uuid2.stdout'
+
+  - name: Check that filesystem is recreated if force is used
+    filesystem:
+      dev: '{{ dev }}'
+      fstype: '{{ fstype }}'
+      force: yes
+    register: fs3_result
+
+  - command: 'blkid -c /dev/null -o value -s UUID {{ dev }}'
+    register: uuid3
+
+  - assert:
+      that:
+        - 'fs3_result is changed'
+        - 'fs3_result is success'
+        - 'uuid.stdout != uuid3.stdout'
+
+  - name: increase fake device
+    shell: 'dd if=/dev/zero bs=1M count=20 >> {{ dev }}'
+
+  - when: 'grow|bool'
+    block:
+    - name: Expand filesystem
+      filesystem:
+        dev: '{{ dev }}'
+        fstype: '{{ fstype }}'
+        resizefs: yes
+      register: fs4_result
+
+    - command: 'blkid -c /dev/null -o value -s UUID {{ dev }}'
+      register: uuid4
+
+    - assert:
+        that:
+          - 'fs4_result is changed'
+          - 'fs4_result is success'
+          - 'uuid3.stdout == uuid4.stdout' # unchanged
+
+    - name: Try to expand filesystem again
+      filesystem:
+        dev: '{{ dev }}'
+        fstype: '{{ fstype }}'
+        resizefs: yes
+      register: fs5_result
+
+    - assert:
+        that:
+          - 'not (fs5_result is changed)'
+          - 'fs5_result is successful'
+
+  - import_tasks: overwrite_another_fs.yml
+
+  always:
+    - file:
+        name: '{{ dev }}'
+        state: absent

test/integration/targets/filesystem/tasks/main.yml

@@ -0,0 +1,19 @@
+- debug:
+    msg: '{{ role_name }}'
+- debug:
+    msg: '{{ role_path|basename }}'
+- import_tasks: setup.yml
+
+- include_tasks: create_fs.yml
+  vars:
+    dev: '{{ ansible_user_dir }}/ansible_testing/img'
+    fstype: '{{ item.key }}'
+    fssize: '{{ item.value.fssize }}'
+    grow: '{{ item.value.grow }}'
+  when:
+    - 'not (item.key == "btrfs" and ansible_system == "FreeBSD")'
+    # On Ubuntu trusty, blkid is unable to identify filesystem smaller than 256Mo, see:
+    # https://www.kernel.org/pub/linux/utils/util-linux/v2.21/v2.21-ChangeLog
+    # https://anonscm.debian.org/cgit/collab-maint/pkg-util-linux.git/commit/?id=04f7020eadf31efc731558df92daa0a1c336c46c
+    - 'not (item.key == "btrfs" and (ansible_distribution == "Ubuntu" and ansible_distribution_release == "trusty"))'
+  loop: "{{ lookup('dict', tested_filesystems) }}"

test/integration/targets/filesystem/tasks/overwrite_another_fs.yml

@@ -0,0 +1,44 @@
+- name: 'Recreate "disk" file'
+  command: 'dd if=/dev/zero of={{ dev }} bs=1M count={{ fssize }}'
+
+- name: 'Create a vfat filesystem'
+  command: 'mkfs.vfat {{ dev }}'
+  when: ansible_system != 'FreeBSD'
+
+- name: 'Create a vfat filesystem'
+  command: 'newfs_msdos -F12 {{ dev }}'
+  when: ansible_system == 'FreeBSD'
+
+- command: 'blkid -c /dev/null -o value -s UUID {{ dev }}'
+  register: uuid
+
+- name: "Check that an existing filesystem (not handled by this module) isn't overwritten when force isn't used"
+  filesystem:
+    dev: '{{ dev }}'
+    fstype: '{{ fstype }}'
+  register: fs_result
+  ignore_errors: True
+
+- command: 'blkid -c /dev/null -o value -s UUID {{ dev }}'
+  register: uuid2
+
+- assert:
+    that:
+      - 'fs_result is failed'
+      - 'uuid.stdout == uuid2.stdout'
+
+- name: "Check that an existing filesystem (not handled by this module) is overwritten when force is used"
+  filesystem:
+    dev: '{{ dev }}'
+    fstype: '{{ fstype }}'
+    force: yes
+  register: fs_result2
+
+- command: 'blkid -c /dev/null -o value -s UUID {{ dev }}'
+  register: uuid3
+
+- assert:
+    that:
+      - 'fs_result2 is successful'
+      - 'fs_result2 is changed'
+      - 'uuid2.stdout != uuid3.stdout'

test/integration/targets/filesystem/tasks/setup.yml

@@ -0,0 +1,45 @@
+- name: install filesystem tools
+  package:
+    name: '{{ item }}'
+    state: present
+  when: ansible_system == 'Linux' or item != 'dosfstools'
+  with_items:
+    - e2fsprogs
+    - xfsprogs
+    - dosfstools
+
+- block:
+  - name: install btrfs progs
+    package:
+      name: btrfs-progs
+      state: present
+    when: ansible_os_family != 'Suse' and not (ansible_distribution == 'Ubuntu' and ansible_distribution_version is version('16.04', '<='))
+
+  - name: install btrfs progs (Ubuntu <= 16.04)
+    package:
+      name: btrfs-tools
+      state: present
+    when: ansible_distribution == 'Ubuntu' and ansible_distribution_version is version('16.04', '<=')
+
+  - name: install btrfs progs (OpenSuse)
+    package:
+      name: '{{ item }}'
+      state: present
+    when: ansible_os_family == 'Suse'
+    with_items:
+      - python-xml
+      - btrfsprogs
+  when: ansible_system == 'Linux'
+
+- command: mke2fs -V
+  register: mke2fs
+
+- set_fact:
+    # mke2fs 1.43.6 (29-Aug-2017)
+    e2fsprogs_version: '{{ mke2fs.stderr_lines[0] | regex_search("[0-9]{1,2}\.[0-9]{1,2}(\.[0-9]{1,2})?") }}'
+
+- set_fact:
+    # http://e2fsprogs.sourceforge.net/e2fsprogs-release.html#1.43
+    # Mke2fs no longer complains if the user tries to create a file system
+    # using the entire block device.
+    force_creation: "{{ e2fsprogs_version is version('1.43', '<') }}"