ansible: lineinfile for several lines?

Question

You can use the lineinfile built-in in a loop. Here's an example:

- name: Set some kernel parameters
  lineinfile:
    dest: /etc/sysctl.conf
    regexp: "{{ item.regexp }}"
    line: "{{ item.line }}"
  loop:
    - { regexp: '^kernel.shmall', line: 'kernel.shmall = 2097152' }
    - { regexp: '^kernel.shmmax', line: 'kernel.shmmax = 134217728' }
    - { regexp: '^fs.file-max', line: 'fs.file-max = 65536' }

You can try using blockinfile instead.

You can do something like

- blockinfile: |
    dest=/etc/network/interfaces backup=yes
    content="iface eth0 inet static
        address 192.168.0.1
        netmask 255.255.255.0"

Here is a noise-free version of the solution which is to use with_items:

- name: add lines
  lineinfile: 
    dest: fruits.txt
    line: '{{ item }}'
  with_items:
    - 'Orange'
    - 'Apple'
    - 'Banana' 

For each item, if the item exists in fruits.txt no action is taken.

If the item does not exist it will be appended to the end of the file.

Easy-peasy.

If you need to configure a set of unique property=value lines, I recommend a more concise loop. For example:

- name: Configure kernel parameters
  lineinfile:
    dest: /etc/sysctl.conf
    regexp: "^{{ item.property | regex_escape() }}="
    line: "{{ item.property }}={{ item.value }}"
  with_items:
    - { property: 'kernel.shmall', value: '2097152' }
    - { property: 'kernel.shmmax', value: '134217728' }
    - { property: 'fs.file-max', value: '65536' }

Using a dict as suggested by Alix Axel and adding automatic removing of matching commented out entries,

- name: Configure IPV4 Forwarding
  lineinfile:
    path: /etc/sysctl.conf
    regexp: "^#? *{{ item.key | regex_escape() }}="
    line: "{{ item.key }}={{ item.value }}"
  with_dict:
    'net.ipv4.ip_forward': 1

It's not ideal, but you're allowed multiple calls to lineinfile. Using that with insert_after, you can get the result you want:

- name: Set first line at EOF (1/3)
  lineinfile: dest=/path/to/file regexp="^string 1" line="string 1"
- name: Set second line after first (2/3)
  lineinfile: dest=/path/to/file regexp="^string 2" line="string 2" insertafter="^string 1"
- name: Set third line after second (3/3)
  lineinfile: dest=/path/to/file regexp="^string 3" line="string 3" insertafter="^string 2"

I was able to do that by using \n in the line parameter.

It is specially useful if the file can be validated, and adding a single line generates an invalid file.

In my case, I was adding AuthorizedKeysCommand and AuthorizedKeysCommandUser to sshd_config, with the following command:

- lineinfile: dest=/etc/ssh/sshd_config line='AuthorizedKeysCommand /etc/ssh/ldap-keys\nAuthorizedKeysCommandUser nobody' validate='/usr/sbin/sshd -T -f %s'

Adding only one of the options generates a file that fails validation.