# var values in the same line

**URL:** <https://forum.ansible.com/t/var-values-in-the-same-line/18641>\
**Category:** Ansible Project\
**Created:** [June 30, 2015, 9:09am UTC](https://forum.ansible.com/t/var-values-in-the-same-line/18641 "2015-06-30T09:09:41Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![Nicolas\_G](https://avatars.discourse-cdn.com/v4/letter/n/a183cd/32.png) [@Nicolas\_G](https://forum.ansible.com/u/Nicolas_G)\
**Post date:** [June 30, 2015, 9:09am UTC](https://forum.ansible.com/t/var-values-in-the-same-line/18641/1 "2015-06-30T09:09:41Z")

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Hi all,

We have a role var defined for every role like bellow :

# roles/db/vars/main.yml :

role : db

# roles/web/vars/main.yml :

role : web

# roles/app/vars/main.yml :

role : app

We need to have this var a specific “config :” line in a configuration file in a way that will be the same if we run 1 single role on a host or all roles :

if we only run the db role the file should be :

# /etc/file.conf :

config: role : db

if we run all roles on the host the file should look like :

# /etc/file.conf :

config: role : db, role: web, role:app

This might look simple but I’m having a hard time to code the logic in Ansible.. any ideas ?

Thanks in advance.

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**Author:** ![PhilEv](https://avatars.discourse-cdn.com/v4/letter/p/ee59a6/32.png) [@PhilEv](https://forum.ansible.com/u/PhilEv)\
**Post date:** [June 30, 2015, 6:55pm UTC](https://forum.ansible.com/t/var-values-in-the-same-line/18641/2 "2015-06-30T18:55:27Z")

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Hi Nicolas,

thinking about a regexp that check and add the string below if not present (e.g: with lineinfile)  
role:

it will use the negative look ahead pattern of regexp

I will pass it to you tomorrow if someone else do not beat me

Stay tuned

Phil

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<div class="post-metadata">

**Author:** ![Nicolas\_G](https://avatars.discourse-cdn.com/v4/letter/n/a183cd/32.png) [@Nicolas\_G](https://forum.ansible.com/u/Nicolas_G)\
**Post date:** [June 30, 2015, 10:59pm UTC](https://forum.ansible.com/t/var-values-in-the-same-line/18641/3 "2015-06-30T22:59:01Z")

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Thank you Phil that will be great.

Looking forward to see your solution.

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**Author:** ![PhilEv](https://avatars.discourse-cdn.com/v4/letter/p/ee59a6/32.png) [@PhilEv](https://forum.ansible.com/u/PhilEv)\
**Post date:** [July 1, 2015, 6:26am UTC](https://forum.ansible.com/t/var-values-in-the-same-line/18641/4 "2015-07-01T06:26:21Z")

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Nicolas,

for clarity I made a small modification to you specification so the config file contains something like below

role: common,web,app,db

then you can use this regexp to check that rolename is not already part of the list

(^role\s\*[:]\s\*(?!rolename)[\w]+)((,(?!rolename)[\w]+)\*)$

for the explanations you can use: [https://regex101.com/](https://regex101.com/)  
to see what’s happening

copy the regexp above in the “Regular Expression” field

for the test use the string below:  
role: rolenam1,common,app,web,rolenam2,db,rolenam3

look at the “MATCH INFORMATION” window and you will get it I think

change rolenam1 to rolename =\> no match

that will be the same for rolenam2 or rolename3

to show the position of the decl does not matter.

then from an Ansible perspective

each role can have a task like below, that will append the rolename to the list if not already done

vars:

- therole: “rolename”
- string: “role: common”

tasks:

- name: check if config exist  
stat: path=“/tmp/config”  
register: stat\_result

- name: start with a basis /tmp/config file  
shell: echo “{{ string }}” \> /tmp/config  
when: stat\_result.stat.exists == False

- name: Append rolename string to the list if not present already  
lineinfile:  
dest=/tmp/config  
backrefs=True  
state=present  
regexp=‘(^role\s\*[:]\s\*(?!rolename)[\w]+)((,(?!rolename)[\w]+)\*)$’  
line=‘\1\2,rolename’

it will be easy to :

- parameterize the rolename string with an ansible variable

relace it with {{therole}} in the lineifile task

- adapt back to you original spec (config: role:app, role:web)

- deal with any number of white spaces

there is one limitation: the need to have a firt role being declared in the config.

It is possible to address this but then the regex will be, say, harder to read

HTH

Phil

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<div class="post-metadata">

**Author:** ![PhilEv](https://avatars.discourse-cdn.com/v4/letter/p/ee59a6/32.png) [@PhilEv](https://forum.ansible.com/u/PhilEv)\
**Post date:** [July 1, 2015, 6:32am UTC](https://forum.ansible.com/t/var-values-in-the-same-line/18641/5 "2015-07-01T06:32:23Z")

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sorry to answer my own post

I should have put a ref to [https://regex101.com/r/xQ6tI0/1](https://regex101.com/r/xQ6tI0/1)