Ansible regex with assert operator - regex

Question

I have the following playbook that is trying to assert that a user prompt variable of NX-OS image equals the ansible_net_image captured from a Nexus switch. This is driving me crazy as to the correct format for the test condition.
---
- name: Upgrade NX-OS on switch with pre-checks to load image as required
hosts: nexus-7000
gather_facts: no
vars_prompt:
- name: NX_OS_Upgrade_Version
prompt: "Please enter NX-OS version to upgrade too - ensure that the filename is as used by boot variable"
private: no
##############################################################################
## Start of task execution
##############################################################################
tasks:
- name: Gather IOS configuration and software facts from switches
nxos_facts:
gather_subset: "!hardware"
################################################################################
## Display running image version to terminal
################################################################################
- debug:
msg: "{{ NX_OS_Upgrade_Version }}"
- assert:
that:
- "ansible_net_image | regex:/^bootflash:\\/\\/\\/(.*) == NX_OS_Upgrade_Version"
Upon execution this error is displayed.
fatal: [switcha]: FAILED! => {"msg": "The conditional check 'ansible_net_image | regex:/^bootflash:\/\/\/(.) == NX_OS_Upgrade_Version' failed. The error was: template error while templating string: expected token 'end of statement block', got '/'. String: {% if ansible_net_image | regex:/^bootflash:\/\/\/(.) == NX_OS_Upgrade_Version %} True {% else %} False {% endif %}"}
fatal: [switchb]: FAILED! => {"msg": "The conditional check 'ansible_net_image | regex:/^bootflash:\/\/\/(.) == NX_OS_Upgrade_Version' failed. The error was: template error while templating string: expected token 'end of statement block', got '/'. String: {% if ansible_net_image | regex:/^bootflash:\/\/\/(.) == NX_OS_Upgrade_Version %} True {% else %} False {% endif %}"}
The regex has been tested, but I am struggling to get the correct syntax for the Ansible play.
It would be great if someone could show me what I have got wrong.

Answer 1

Use 7.3.2. Single-Quoted Style to create regex.
See Testing strings.
For example
- hosts: localhost
vars:
ansible_net_image: 'bootflash:///n5000-uk9-kickstart.5.1.3.N2.1b.bin'
NX_OS_Upgrade_Version1: 'n5000-uk9-kickstart.5.1.3.N2.1b'
my_regex1: '^bootflash:///{{ NX_OS_Upgrade_Version1 }}.bin'
NX_OS_Upgrade_Version2: 'n5000-uk9-kickstart.5.1.4.N2.1b'
my_regex2: '^bootflash:///{{ NX_OS_Upgrade_Version2 }}.bin'
tasks:
- assert:
that: ansible_net_image is match(my_regex1)
success_msg: "Image is version {{ NX_OS_Upgrade_Version1 }}"
fail_msg: "Image is NOT version {{ NX_OS_Upgrade_Version1 }}"
- assert:
that: ansible_net_image is match(my_regex2)
success_msg: "Image is version {{ NX_OS_Upgrade_Version2 }}"
fail_msg: "Image is NOT version {{ NX_OS_Upgrade_Version2 }}"
gives
ok: [localhost] => {
"changed": false,
"msg": "Image is version n5000-uk9-kickstart.5.1.3.N2.1b"
}
fatal: [localhost]: FAILED! => {
"assertion": "ansible_net_image is match(my_regex2)",
"changed": false,
"evaluated_to": false,
"msg": "Image is NOT version n5000-uk9-kickstart.5.1.4.N2.1b"
}