I have to check whether a file exists in /etc/
. If the file exists then I have to skip the task.
Here is the code I am using:
- name: checking th
You can first check that the destination file exists or not and then make a decision based on the output of its result:
tasks:
- name: Check that the somefile.conf exists
stat:
path: /etc/file.txt
register: stat_result
- name: Create the file, if it doesnt exist already
file:
path: /etc/file.txt
state: touch
when: not stat_result.stat.exists
Discovered that calling stat
is slow and collects a lot of info that is not required for file existence check.
After spending some time searching for solution, i discovered following solution, which works much faster:
- raw: test -e /path/to/something && echo true || echo false
register: file_exists
- debug: msg="Path exists"
when: file_exists == true
I find it can be annoying and error prone to do a lot of these .stat.exists
type checks. For example they require extra care to get check mode (--check
) working.
Many answers here suggest
However, sometimes this is a code smell so always look for better ways to use Ansible, specifically there are many advantages to using the correct module. e.g.
- name: install ntpdate
package:
name: ntpdate
or
- file:
path: /etc/file.txt
owner: root
group: root
mode: 0644
But when it is not possible use one module, also investigate if you can register and check the result of a previous task. e.g.
# jmeter_version: 4.0
- name: Download Jmeter archive
get_url:
url: "http://archive.apache.org/dist/jmeter/binaries/apache-jmeter-{{ jmeter_version }}.tgz"
dest: "/opt/jmeter/apache-jmeter-{{ jmeter_version }}.tgz"
checksum: sha512:eee7d68bd1f7e7b269fabaf8f09821697165518b112a979a25c5f128c4de8ca6ad12d3b20cd9380a2b53ca52762b4c4979e564a8c2ff37196692fbd217f1e343
register: download_result
- name: Extract apache-jmeter
unarchive:
src: "/opt/jmeter/apache-jmeter-{{ jmeter_version }}.tgz"
dest: "/opt/jmeter/"
remote_src: yes
creates: "/opt/jmeter/apache-jmeter-{{ jmeter_version }}"
when: download_result.state == 'file'
Note the when:
but also the creates:
so --check
doesn't error out
I mention this because often these less-than-ideal practices come in pairs i.e. no apt/yum package so we have to 1) download and 2) unzip
Hope this helps
The stat module will do this as well as obtain a lot of other information for files. From the example documentation:
- stat: path=/path/to/something
register: p
- debug: msg="Path exists and is a directory"
when: p.stat.isdir is defined and p.stat.isdir
In general you would do this with the stat module. But the command module has the creates
option which makes this very simple:
- name: touch file
command: touch /etc/file.txt
args:
creates: /etc/file.txt
I guess your touch command is just an example? Best practice would be to not check anything at all and let ansible do its job - with the correct module. So if you want to ensure the file exists you would use the file module:
- name: make sure file exists
file:
path: /etc/file.txt
state: touch
**
**
Below is the ansible play i used to remove the file when the file exists in the OS end.
- name: find out /etc/init.d/splunk file exists or not'
stat:
path: /etc/init.d/splunk
register: splunkresult
tags:
- always
- name: 'Remove splunk from init.d file if splunk already running'
file:
path: /etc/init.d/splunk
state: absent
when: splunkresult.stat.exists == true
ignore_errors: yes
tags:
- always
I have used play condition as like below
when: splunkresult.stat.exists == true --> Remove the file
you can give true/false based on your requirement
when: splunkresult.stat.exists == false
when: splunkresult.stat.exists == true