Linked Templates not updated with xml/json templates

[rockaut]

SUMMARY

If you import a template with a xml/json file the linked templates of a templates ( so the child templates not the root ones ) aren't processed if you want to remove linked templates.

ISSUE TYPE

• Bug Report

COMPONENT NAME

zabbix_templates

ANSIBLE VERSION

ansible 2.9.2
  config file = /mnt/d/Code/gitlab/zabbix-servers/ansible/ansible.cfg
  configured module search path = ['/home/fism/.ansible/plugins/modules', '/usr/share/ansible/plugins/modules']
  ansible python module location = /mnt/d/Code/gitlab/zabbix-servers/venv/lib/python3.6/site-packages/ansible
  executable location = /mnt/d/Code/gitlab/zabbix-servers/venv/bin/ansible
  python version = 3.6.9 (default, Nov  7 2019, 10:44:02) [GCC 8.3.0]

OS / ENVIRONMENT

Zabbix 4.4.4 on RHEL7

STEPS TO REPRODUCE

Export a template (no matter if with Zabbix itself or ansible). Change the corresponding linked template section of a template and reimport it.

Exported with Zabbix:

<zabbix_export>
    <version>4.4</version>
    <date>2020-01-23T13:25:32Z</date>
    <groups>
        <group>
            <name>Templates</name>
        </group>
    </groups>
    <templates>
        <template>
            <template>fisma</template>
            <name>fisma</name>
            <templates>
                <template>
                    <name>fismb</name>
                </template>
            </templates>
            <groups>
                <group>
                    <name>Templates</name>
                </group>
            </groups>
        </template>
    </templates>
</zabbix_export>

Change to this with removing all linked templates ( fismb in above example ).

<zabbix_export>
    <version>4.4</version>
    <date>2020-01-23T13:25:32Z</date>
    <groups>
        <group>
            <name>Templates</name>
        </group>
    </groups>
    <templates>
        <template>
            <template>fisma</template>
            <name>fisma</name>
            <groups>
                <group>
                    <name>Templates</name>
                </group>
            </groups>
        </template>
    </templates>
</zabbix_export>

EXPECTED RESULTS

fismb should be unlinked from fisma.

ACTUAL RESULTS

fismb is still linked with fisma.

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Files identified in the description:
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[rockaut]

Also:

• fisma with linked fismb, fismc
  if you want to remove only fismb it doesn't change. But Ansible is reporting the "changed": true state.

Linking on creation of a new template is working.

[rockaut]

Actually I can't really wrap my head around that propblem. Maybe @sky-joker @D3DeFi can comment on it.

As i see it, the linked templates are read out in the check_template_changed function but at nowhere other. Also there are variables like link_template_ids mentioned often in code but they aren't the linked templates/child templates but the template id under the root templates nodes.

Also I don't know how this currently could work with multiple templates in one file as those nodes aren't iterated over.

If you look at zabbix_template.py line 680:

    # Identify template names for IDs retrieval
    # Template names are expected to reside in ['zabbix_export']['templates'][*]['template'] for both data types
    template_content, template_type = None, None
    if template_json is not None:
        template_type = 'json'
        template_content = template_json
        json_parsed = template.load_json_template(template_content)
        template_names = list(t['template'] for t in json_parsed['zabbix_export']['templates'])

    elif template_xml is not None:
        template_type = 'xml'
        template_content = template_xml
        xml_parsed = template.load_xml_template(template_content)
        template_names = list(t.find('template').text for t in list(xml_parsed.find('templates')))

    else:
        template_names = [template_name]

Here only the content and the names of the templates are "read" out but things like macros not.

What I don't get: the whole thing is then "just" imported in function import_template as is. So no parsing or anything should be impacting the actual changes. All that might influence this things are the update_rules. But here nothing can be changed.

[rockaut]

Now I get it ... but it's still cumbersome.

There are two ways to do this in the Zabbix API: with template.update and with configuration.import.

If you use template.update - which i thought where the case for ansible - all would work as I was expecting it. If you look at https://www.zabbix.com/documentation/4.4/manual/api/reference/template/update there is this statement for templates:

Templates to replace the currently linked templates. Templates that are not passed are only unlinked.

So if you want to unlink a template from another template just don't pass it.

The current Ansible implementation for importing xml/json file is using configuration.import instead. And here this whole process doesn't work as describe. In fact if you use the import function of the zabbix frontend it also doesn't work this way.

What do you others think of this?

[rockaut]

I opened a Zabbix issue too ( https://support.zabbix.com/browse/ZBX-17215 ) - I think this might be a issue for the Zabbix team as the API should work consistently here. That said I'm not shure if it shouldn't be covered in the Ansible module too somehow. At least it should be mentioned in the docs?

[Akasurde]

!component =lib/ansible/modules/monitoring/zabbix/zabbix_template.py

[ansibot]

Files identified in the description:

• lib/ansible/modules/monitoring/zabbix/zabbix_template.py

If these files are inaccurate, please update the component name section of the description or use the !component bot command.

click here for bot help

[ansibot]

cc @logan2211 @rubentsirunyan @sookido
click here for bot help

[rockaut]

Tested with Zabbix 4.4.4 against the new options metioned in Zabbix Issue. Works now as expected.

Added PR for new API update rule.

[D3DeFi]

Thanks @rockaut for such a deep analysis of the problem. The thing with importing multiple templates at once is only supported thanks to configuration.import from Zabbix API as you've already found out. The module itself is not very well suited to detect changes on more than one template, that's why I always try to talk about importing multiple templates via XML/JSON files as an experimental feature.

If we would to change to template.update API call we would need to carefully parse XML/JSON by ourselves instead of relaying on the Zabbix itself to load necessary dependencies (template ids, groups ids and so on). To be honest, this module as well as some other zabbix modules are a bit messy and could really use some major overhaul.

Anyways, thanks for providing a PR for this issue! Good job.

[rockaut]

Oh I totally get why it is how it is and I also think it's better than actually parse the xml/json as it would be way to error-prone. That's why I thought it should be handled in Zabbix API ... and now it's already present :D

That said ... I still think it should somehow be mentioned in the readme for the ansible module somehow. Booth things actually, the configuration.import and the multi-object thing. Multi-object isn't only hitting templates but also host as I see it?

I will wrap my thoughts about it next week and maybe contribute something so that we can discuss this aside from this issue/pr.