HELP for Replace module regex

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1

Hi All,

I am try to figure out the regex exp that will catch a key in a yaml file but i am not getting the way to pass through. I hope that you expertise on this can help me.

Problem Statement: I have a yaml file (which will be dynamic), where i need to replace a specific key value.

Example: in the below yaml file i only need to update “id” value which is under payroll_emp in the all the file.

If i am using regex: id:.* this will catch all the id in the file.

Help Needed: if there a way that i can have a regex to match the id under payroll_emp and change the value id: 1000 to id: 2000 .

NOTE: we can’t use the after and before parameter as this file will be dynamic its not sure what will be before and after id

2

What does your ansible task look like?

3

Hi Dick,

Thank you for the response.

as you see the commented code where i was trying use the after: ‘payroll_emp.*’ it does not do anything and i use the replace without any guard then all the id: xxxxx gets change with id: 2000

4

Ah Ok, i see.
Using a string manipulating module like replace is inherently fragile,
so whatever works now may break tomorrow (as you pointed out).
Since your input is yaml, I would look into another approach, like
lookup the file content, parse it as yaml, change the required
keys/values, and then write the file back.
This way is more robust in terms of input (the ordering/comments/etc
won't matter), and also output, as that will be valid yaml.

5

Agreed to what you have pointed out.

But my apologies as i have lack of knowledge to do such level of parsing as i have just started with ansible.

it will be great help if you can help me on this. Also, a pointer the value that need to be change will be passed using the with_items: xxxx, as value is fetch in previous task and store as a set fact.

6

Hi All,

can anyone me out on this. i had been trying to check around the regex but no luck

7

Hi Manisha,
I just looked into your issue and found that you’re using only id for replacement which gives you wrong output so instead of using it use the below syntax

tasks:

  • name: Replaces all the IDs from 1000 to 2000.
    replace:
    path:
    regexp: ‘id: 1000’
    replace: ‘id: 2000’

And yes similarly for replacing 1001 with 2001 you’ve to add one more replace module.
If this is helpful for you then its really grateful for me.

Thanks & Regards,
Shrasti Sahni