replace - Replace all instances of a particular string in a file using a back-referenced regular expression.

New in version 1.6.

Synopsis

  • This module will replace all instances of a pattern within a file.
  • It is up to the user to maintain idempotence by ensuring that the same pattern would never match any replacements made.

Options

parameter required default choices comments
after
(added in 2.4)
no
If specified, the line after the replace/remove will start. Can be used in combination with before. Uses Python regular expressions; see http://docs.python.org/2/library/re.html.
attributes
(added in 2.3)
no None
Attributes the file or directory should have. To get supported flags look at the man page for chattr on the target system. This string should contain the attributes in the same order as the one displayed by lsattr.
aliases: attr
backup
no no
  • yes
  • no
Create a backup file including the timestamp information so you can get the original file back if you somehow clobbered it incorrectly.
before
(added in 2.4)
no
If specified, the line before the replace/remove will occur. Can be used in combination with after. Uses Python regular expressions; see http://docs.python.org/2/library/re.html.
encoding
(added in 2.4)
no utf-8
The character encoding for reading and writing the file.
follow
(added in 1.9)
no no
  • yes
  • no
This flag indicates that filesystem links, if they exist, should be followed.
group
no
Name of the group that should own the file/directory, as would be fed to chown.
mode
no
Mode the file or directory should be. For those used to /usr/bin/chmod remember that modes are actually octal numbers (like 0644). Leaving off the leading zero will likely have unexpected results. As of version 1.8, the mode may be specified as a symbolic mode (for example, u+rwx or u=rw,g=r,o=r).
others
no
All arguments accepted by the file module also work here.
owner
no
Name of the user that should own the file/directory, as would be fed to chown.
path
yes
The file to modify.
Before 2.3 this option was only usable as dest, destfile and name.
aliases: dest, destfile, name
regexp
yes
The regular expression to look for in the contents of the file. Uses Python regular expressions; see http://docs.python.org/2/library/re.html. Uses MULTILINE mode, which means ^ and $ match the beginning and end of the file, as well as the beginning and end respectively of each line of the file.
Does not use DOTALL, which means the . special character matches any character except newlines. A common mistake is to assume that a negated character set like [^#] will also not match newlines. In order to exclude newlines, they must be added to the set like [^#\n].
Note that, as of ansible 2, short form tasks should have any escape sequences backslash-escaped in order to prevent them being parsed as string literal escapes. See the examples.
replace
no
The string to replace regexp matches. May contain backreferences that will get expanded with the regexp capture groups if the regexp matches. If not set, matches are removed entirely.
selevel
no s0
Level part of the SELinux file context. This is the MLS/MCS attribute, sometimes known as the range. _default feature works as for seuser.
serole
no
Role part of SELinux file context, _default feature works as for seuser.
setype
no
Type part of SELinux file context, _default feature works as for seuser.
seuser
no
User part of SELinux file context. Will default to system policy, if applicable. If set to _default, it will use the user portion of the policy if available.
unsafe_writes
(added in 2.2)
no
  • yes
  • no
Normally this module uses atomic operations to prevent data corruption or inconsistent reads from the target files, sometimes systems are configured or just broken in ways that prevent this. One example are docker mounted files, they cannot be updated atomically and can only be done in an unsafe manner.
This boolean option allows ansible to fall back to unsafe methods of updating files for those cases in which you do not have any other choice. Be aware that this is subject to race conditions and can lead to data corruption.
validate
no None
The validation command to run before copying into place. The path to the file to validate is passed in via '%s' which must be present as in the example below. The command is passed securely so shell features like expansion and pipes won't work.

Examples

# Before 2.3, option 'dest', 'destfile' or 'name' was used instead of 'path'
- replace:
    path: /etc/hosts
    regexp: '(\s+)old\.host\.name(\s+.*)?$'
    replace: '\1new.host.name\2'
    backup: yes

# Replace after the expression till the end of the file (requires >=2.4)
- replace:
    path: /etc/hosts
    regexp: '(\s+)old\.host\.name(\s+.*)?$'
    replace: '\1new.host.name\2'
    after: 'Start after line.*'
    backup: yes

# Replace before the expression till the begin of the file (requires >=2.4)
- replace:
    path: /etc/hosts
    regexp: '(\s+)old\.host\.name(\s+.*)?$'
    replace: '\1new.host.name\2'
    before: 'Start before line.*'
    backup: yes

# Replace between the expressions (requires >=2.4)
- replace:
    path: /etc/hosts
    regexp: '(\s+)old\.host\.name(\s+.*)?$'
    replace: '\1new.host.name\2'
    after: 'Start after line.*'
    before: 'Start before line.*'
    backup: yes

- replace:
    path: /home/jdoe/.ssh/known_hosts
    regexp: '^old\.host\.name[^\n]*\n'
    owner: jdoe
    group: jdoe
    mode: 0644

- replace:
    path: /etc/apache/ports
    regexp: '^(NameVirtualHost|Listen)\s+80\s*$'
    replace: '\1 127.0.0.1:8080'
    validate: '/usr/sbin/apache2ctl -f %s -t'

- name: short form task (in ansible 2+) necessitates backslash-escaped sequences
  replace: dest=/etc/hosts regexp='\\b(localhost)(\\d*)\\b' replace='\\1\\2.localdomain\\2 \\1\\2'

- name: long form task does not
  replace:
    dest: /etc/hosts
    regexp: '\b(localhost)(\d*)\b'
    replace: '\1\2.localdomain\2 \1\2'

Notes

Note

  • As of Ansible 2.3, the dest option has been changed to path as default, but dest still works as well.

Status

This module is flagged as stableinterface which means that the maintainers for this module guarantee that no backward incompatible interface changes will be made.

For help in developing on modules, should you be so inclined, please read Community Information & Contributing, Testing Ansible and Developing Modules.

© 2012–2018 Michael DeHaan
© 2018–2019 Red Hat, Inc.
Licensed under the GNU General Public License version 3.
https://docs.ansible.com/ansible/2.4/replace_module.html