# (developers) First peek at the ansible-commander data layer **URL:** \ **Category:** Ansible Project\ **Created:** [September 8, 2012, 5:03pm UTC](https://forum.ansible.com/t/developers-first-peek-at-the-ansible-commander-data-layer/11875 "2012-09-08T17:03:24Z")\ **Posts on this page:** 5\ **Page:** 1
**Author:** ![Michael\_DeHaan](https://avatars.discourse-cdn.com/v4/letter/m/c4cdca/32.png) [@Michael\_DeHaan](https://forum.ansible.com/u/Michael_DeHaan)\ **Post date:** [September 8, 2012, 5:03pm UTC](https://forum.ansible.com/t/developers-first-peek-at-the-ansible-commander-data-layer/11875/1 "2012-09-08T17:03:24Z")
As I mentioned earlier, I'm going to keep everyone updated as ansible-commander evolves. What you now see in the repo is the result of only a few hours of hacking. As it turns out, as is always the case, that the latest shiny toys you want to use on CentOS 6 are never there. In this case, the psycopg2 extensions for hstore were MIA, so I decided to not use hstore -- which also makes things easier to set up. Ah well. I don't think we need it, and it will lower the complexity of the SQL anyway.     [https://github.com/ansible/ansible-commander/blob/master/acom/data.py](https://github.com/ansible/ansible-commander/blob/master/acom/data.py) This is a really rough sketch of a NewSql-style data layer in Postgres, as you can see, adding a new type of object is going to be pretty simple. It's following the Reddit model of only having two tables, so we don't have to worry about migrations. There's more to add like a function to check the data types and general sanity, but you can see the basics here. This is enough to start plumbing up the basics of the REST API. One of the things the REST API is going to have to do is keep track of some cached data, so when we add a group to a parent group it will keep up all the kid hosts and grandkid groups, etc -- to make things nice and fast. The API will not allow editing these, but will be updated behind the scenes when edits are made. This is still left to be done. So, the next step is to flesh out the REST API for groups to the point where we can exercise it. Users will work just like groups. The app will automatically insert a default user if there are none, and you'll be able to edit your password using the REST API. API users will never need to know the database password, but there is one, and the Ansible app can only access the Ansible database. --Michael ---
**Author:** ![Stephen\_John\_Smoogen](https://avatars.discourse-cdn.com/v4/letter/s/ad7895/32.png) [@Stephen\_John\_Smoogen](https://forum.ansible.com/u/Stephen_John_Smoogen)\ **Post date:** [September 8, 2012, 6:28pm UTC](https://forum.ansible.com/t/developers-first-peek-at-the-ansible-commander-data-layer/11875/2 "2012-09-08T18:28:01Z")
I noticed that you were earlier dealing with Centos 5 issues with the ansible layer.. will you be needing to do so for the commander too? ---
**Author:** ![Michael\_DeHaan](https://avatars.discourse-cdn.com/v4/letter/m/c4cdca/32.png) [@Michael\_DeHaan](https://forum.ansible.com/u/Michael_DeHaan)\ **Post date:** [September 8, 2012, 6:30pm UTC](https://forum.ansible.com/t/developers-first-peek-at-the-ansible-commander-data-layer/11875/3 "2012-09-08T18:30:28Z")
> I noticed that you were earlier dealing with Centos 5 issues with the > ansible layer.. will you be needing to do so for the commander too? Ansible-commander will require python 2.6, Flask, and psycopg2. Provided folks install the appropriate libraries, it should work, but it's not something I'm going to go out of my way to support. (Ansible itself similarly requires Python 2.6 on the central machine, but supports 2.4 nodes) --Michael ---
**Author:** ![Marco\_Vito\_Moscarito](https://avatars.discourse-cdn.com/v4/letter/m/97f17d/32.png) [@Marco\_Vito\_Moscarito](https://forum.ansible.com/u/Marco_Vito_Moscarito)\ **Post date:** [September 8, 2012, 9:10pm UTC](https://forum.ansible.com/t/developers-first-peek-at-the-ansible-commander-data-layer/11875/4 "2012-09-08T21:10:31Z")
Great work Michael! Maybe remove Postgree dependencies to a light weight DB (sqlite?) can make ansible-commander more "ready-to-go" and self-contained, but make data directly accessible from other (non-python) application. Bye        Marco ---
**Author:** ![Michael\_DeHaan](https://avatars.discourse-cdn.com/v4/letter/m/c4cdca/32.png) [@Michael\_DeHaan](https://forum.ansible.com/u/Michael_DeHaan)\ **Post date:** [September 8, 2012, 11:16pm UTC](https://forum.ansible.com/t/developers-first-peek-at-the-ansible-commander-data-layer/11875/5 "2012-09-08T23:16:51Z")
Just PostgreSQL for now. Can think about that much later once things level out. Groups have unit tests for basic things now, I have to add the logic to save their cached relations, and then we can start wiring them up into REST. Representing treeishness in NoSQLish SQL is a good way to fry your brain. Though thankfully also somewhat fun in retrospect. --Michael