# Matching against any nested elements in a variable **URL:** \ **Category:** Ansible Project\ **Created:** [September 6, 2013, 9:35pm UTC](https://forum.ansible.com/t/matching-against-any-nested-elements-in-a-variable/13430 "2013-09-06T21:35:45Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Kent\_R\_Spillner](https://avatars.discourse-cdn.com/v4/letter/k/ea5d25/32.png) [@Kent\_R\_Spillner](https://forum.ansible.com/u/Kent_R_Spillner)\ **Post date:** [September 6, 2013, 9:35pm UTC](https://forum.ansible.com/t/matching-against-any-nested-elements-in-a-variable/13430/1 "2013-09-06T21:35:45Z")
I want to use Ansible to install the appropriate RAID controller utility for every server but work in a fairly mixed environment with different vendors and different RAID controllers. I think the best way to handle this is by writing a custom module that provides a raid\_controller\_manufacturer fact, but before I do I wanted to see if it would be possible to just do some fuzzy matching on nested elements in the ansible\_devices fact. Here's a partial snippet from running setup against a SuperMicro server with an LSI controller: "ansible\_devices": {     "sda": {         "host": "RAID bus controller: LSI Logic / Symbios Logic MegaRAID SAS 2108 [Liberator] (rev 04)"     } } Here's a partial snippet from running setup against another SuperMicro with an Adaptec controller: "ansible\_devices": {     "sda": {         "host": "RAID bus controller: Adaptec AAC-RAID (rev 09)"     } } And here's another partial snippet from running setup against an HP with an HP SmartArray controller: "ansible\_devices": {     "cciss!c0d0": {         "host": "RAID bus controller: Hewlett-Packard Company Smart Array Controller (rev 04)"      } } So, long story short is there a way to do something akin to the following: - name: Install HP SmartArray util   yum: name=hpacucli state=latest   when: ansible\_devices.\*.host contains "Hewlett-Packard Company Smart Array Controller" - name: Install LSI MegaRaid util   yum: name=MegaCli state=latest   when: ansible\_devices.\*.host contains "LSI Logic / Symbios Logic MegaRAID" - name: Install Adaptec util   yum: name=aacraid state=latest   when: ansible\_devices.\*.host contains "Adaptec AAC-RAID" ---
**Author:** ![Serge\_van\_Ginderacht](https://avatars.discourse-cdn.com/v4/letter/s/b782af/32.png) [@Serge\_van\_Ginderacht](https://forum.ansible.com/u/Serge_van_Ginderacht)\ **Post date:** [September 6, 2013, 9:49pm UTC](https://forum.ansible.com/t/matching-against-any-nested-elements-in-a-variable/13430/2 "2013-09-06T21:49:57Z")
​maybe we should have the values of lspci (and lsusb)​ in setup? ---
**Author:** ![Michael\_DeHaan2](https://avatars.discourse-cdn.com/v4/letter/m/da6949/32.png) [@Michael\_DeHaan2](https://forum.ansible.com/u/Michael_DeHaan2)\ **Post date:** [September 6, 2013, 9:55pm UTC](https://forum.ansible.com/t/matching-against-any-nested-elements-in-a-variable/13430/3 "2013-09-06T21:55:12Z")
Nothing presently doable as the “when” is more or less a Python expression. (also this quickly spirals into complicated because you could have more than one raid card) lspci data quickly bloats setup results, so it seems like a custom fact module may be best here. ---
**Author:** ![Kent\_R\_Spillner](https://avatars.discourse-cdn.com/v4/letter/k/ea5d25/32.png) [@Kent\_R\_Spillner](https://forum.ansible.com/u/Kent_R_Spillner)\ **Post date:** [September 6, 2013, 11:20pm UTC](https://forum.ansible.com/t/matching-against-any-nested-elements-in-a-variable/13430/4 "2013-09-06T23:20:02Z")
> lspci data quickly bloats setup results, so it seems like a custom fact > module may be best here. Cool, thanks Serge and Michael for your responses! ---
**Author:** ![Kent\_R\_Spillner](https://avatars.discourse-cdn.com/v4/letter/k/ea5d25/32.png) [@Kent\_R\_Spillner](https://forum.ansible.com/u/Kent_R_Spillner)\ **Post date:** [September 9, 2013, 8:27pm UTC](https://forum.ansible.com/t/matching-against-any-nested-elements-in-a-variable/13430/5 "2013-09-09T20:27:10Z")
> (also this quickly spirals into complicated because you could have more > than one raid card) > > lspci data quickly bloats setup results, so it seems like a custom fact > module may be best here. Is there a way to access facts directly from a Python module? I wrote the raid\_controller\_facts module today. I'm using the common module boilerplate as described in the docs. Rather than call lspci a second time and parse the output again (the first time being in the setup module) I'm cheating and passing ansible\_devices as an argument to my module: - name: Gather RAID controller facts   raid\_controller\_facts:     devices: "{{ ansible\_devices }}" And then in the implementation I iterate through module.params["devices"] and check if the host field contains the word RAID. I've got it all working fine, but ansible\_devices is being converted to a string value before being passed to my module so I use ast.literal\_eval to convert it back to a hash. Besides avoiding the unnecessary conversion to string and back, I have a few servers with Python 2.4.2 so the ast module isn't available, and my module doesn't work on them. So, long story short, if I could access the ansible\_devices fact directly in my module then I could avoid a little busy work and work on systems with older Python installs. ---
**Author:** ![Michael\_DeHaan2](https://avatars.discourse-cdn.com/v4/letter/m/da6949/32.png) [@Michael\_DeHaan2](https://forum.ansible.com/u/Michael_DeHaan2)\ **Post date:** [September 9, 2013, 11:16pm UTC](https://forum.ansible.com/t/matching-against-any-nested-elements-in-a-variable/13430/6 "2013-09-09T23:16:56Z")
Nope, you would have to pass them in. If you are doing complex arguments, when you say " {{ foo }}" you are requesting a string. This is the _one_ case where the old style var is still useful, to indicate you want a reference, which I still think we need a syntax for. raid\_controller\_facts: devices: $devices Should work for you. ---
**Author:** ![Kent\_R\_Spillner](https://avatars.discourse-cdn.com/v4/letter/k/ea5d25/32.png) [@Kent\_R\_Spillner](https://forum.ansible.com/u/Kent_R_Spillner)\ **Post date:** [September 10, 2013, 4:26pm UTC](https://forum.ansible.com/t/matching-against-any-nested-elements-in-a-variable/13430/7 "2013-09-10T16:26:10Z")
> This is the \*one\* case where the old style var is still useful, to indicate > you want a reference, which I still think we need a syntax for. > > raid\_controller\_facts: >    devices: $devices > > Should work for you. Yep, that worked perfectly. Thanks!