The inventory is a Resgate service that allows Resgate clients to subscribe
to data in an abstract Storage.
A File based Storage that uses directories and yaml-files to store data of arbitrary complexity. This storage supports
CRUD.
This Storage can contain Bolt targets defined in YAML-files using the
Bolt Inventory 2 file format.
The storage is read-only from Resgate's point of view but sensitive to changes in the file system. The reasons for this design are:
- The main reason to be able to update the inventory in the first place is for test purposes only. In a production scenario, the inventory will reflect data stored elsewhere. Tests can swap the underlying yaml files instead of using proper Resgate events to update their content.
- It's inherently hard to make changes to a target and determine where in the group hierarchy that change should be stored.
- The most likely scenario moving forward is either that files will be extracted from PuppetDB somehow or that
a storage, similar to the
bolt.Storageincluded in the POC, will access PuppetDB directly.
CRUD support can of course be added later, should the need arise.
Easiest way to get Resgate and NATS up and running is to use install Docker. Then do:
docker network create res
docker run -d --name nats -p 4222:4222 --net res nats
docker run -d --name resgate -p 8080:8080 --net res resgateio/resgate --nats nats://nats:4222
Now cd into the <project root>/examples/targets directory (main.go relies on that this is the current working directory) and start the sample service:
cd <project root>examples/targets
go run main.go
Something similar to this should be displayed on the console:
Client at: http://localhost:8084/
INFO[0000] Connecting to NATS server
INFO[0000] Starting service
INFO[0000] Listening for requests
This service will load and listen to the files found under <project root>/testdata/volatile/bolt. There are two of them named realm_a.yaml and realm_b.yaml. These files are Bolt Inventory 2 files and the bolt storage will consider them to be two different realms.
The service also starts a webclient on http://localhost:8084. Direct the browser to that URL and a sample web page that connects to Resgate and displays the targets will be displayed.
Now the fun starts. Try editing the realm files (don't worry, they are recreated when the sample service starts). Add new facts to groups, change some config, add a new target. Meanwhile, watch what happens on the webpage as the changes are detected by the Bolt Storage and published to Resgate.