Compare version numbers using jinja2

Question

I am using jinja2 template to install/upgrade packages.

The logic was setting a variable for current installed version and compare it with the available version. It was working fine but once we passed in to 10.x, comparison quit working.

Is it possible to cast the variable so it can correctly identify 10.9.8 is greater than 9.8.7?

Thanks

current_version=['9.8.7']

{% if current_version < '10.9.8' %}

I guess I can try to remove the dots and cast them to integer and then compare. How would one go about deleting dots in jinja2? — BBDG, Sep 20 '17 at 14:21
I ended up using != to compare installed version string to the version I want to have installed on the server. — BBDG, Sep 20 '17 at 19:45
Possible duplicate of [How to compare version strings in salt sls files](https://stackoverflow.com/questions/45701907/how-to-compare-version-strings-in-salt-sls-files) — ceving, Sep 21 '17 at 08:52

score 13 · Answer 1 · edited Mar 21 '21 at 03:00

13

There's a special test version_compare:

{% if current_version | version_compare('10.9.8', '<') %}

current_version should be string (it is a list in your example).

edited Mar 21 '21 at 03:00

MiSHuTka

1,071
1
11
20

answered Sep 20 '17 at 15:32

Konstantin Suvorov

60,467
8
142
174

Very good to know. This specific use case is deployed with salt-stack. Apparently "version_compare" filter is not implemented in salt-stack. Thank you for response. – BBDG Sep 20 '17 at 16:09
7

Why did you put `ansible` tag in this case? – Konstantin Suvorov Sep 20 '17 at 16:16
1

this is ansible only – Wang Jul 10 '20 at 16:32
1

For Ansible > 2.5, version_compare has been replaced by version. https://docs.ansible.com/ansible/latest/user_guide/playbooks_tests.html – ouzmoutous Dec 18 '20 at 14:54
I couldn't get this to work in Ansible Jinja templates – Jacob Degeling Jul 07 '21 at 00:41

score 2 · Answer 2 · answered Apr 16 '21 at 12:01

2

Using plain jinja2, without ansible or other extensions:

{% if my_version.split('.') | map('int') | list >= [10, 9, 8]  %}

By converting each element to int, you ensure it won't compare lexicographically.

answered Apr 16 '21 at 12:01

Kira

465
4
12

cglacet · Answer 3 · 2021-04-16T22:16:52.027

1

With Jinja2

Using split and because of how sequence comparison work, the following should do just fine:

{% if current_version.split('.') | map('int') < '10.9.8'.split('.') | map('int') %}

Test:

Split: {{ current_version.split('.') }}
Split + cast: {{ current_version.split('.') | map('int') }}
---
Is {{ current_version.split('.') | map('int') }} < {{ '10.9.8'.split('.') | map('int') }}?
{% if current_version.split('.') | map('int') < '10.9.8'.split('.') | map('int') %}
Yes
{% endif %}

Which, with current_version: "9.8.7" gives:

Split: ['9', '8', '7']
Split + cast: [9, 8, 7]
---
Is [9, 8, 7] < [10, 9, 8]?
Yes

edited Apr 16 '21 at 22:16

answered Nov 14 '20 at 22:44

cglacet

6,638
2
35
49

This solution fails the exactly same way as OP's. `['1','2'] < ['1','10'] == False` – Kira Apr 16 '21 at 11:32
Ah, good catch, you are right. It missed the `int` cast, now it should work. Let me know if there's another problem. – cglacet Apr 16 '21 at 22:17

score 0 · Answer 4 · answered Sep 21 '17 at 06:47

0

In saltstack you can use pkg.version_cmp

See my reply here: How to compare version strings in salt sls files

answered Sep 21 '17 at 06:47

ProT-0-TypE

283
2
8

Compare version numbers using jinja2

4 Answers4

With Jinja2

Linked