Papiea - Prescriptive and Practical Intent Engine Architecture

Papiea, pronounced like the fruit, is an Intent engine based on perscriptions or recipes for handling differences between intended state and real world state.

Managing system state, especially when state is comprised of multiple seperated individual parts is a complex task. Papiea allows entites to be in two states: desired and real, named "spec" and "status" respectively. Providers are the mechanism which help Papiea transition an entity from its real state (or its "status") to its desired state (or its "spec"). Three mechanisms are involved in such process:

1. Add - an entity has only spec but no status. The entity must be created in the real world which will be reflected in its status
2. Del - an entity has only status but no spec. The entity must be removed from the real world
3. Change - an entity has a both spec and status, but they differ. The entity must be changed in the real world.

Usage

Set up the enviroment

For now the system relies on MongoDB to be set up. The simplest way to use it is through docker. Directions taken from here:

Set up a new docker instance and run it

docker run -d --name papiea-mongo -p 27017:27017 -v ~/work/mongodb-docker/data:/data/db mvertes/alpine-mongo

Stop it

docker kill papiea-mongo

Access it:

docker exec -ti papiea-mongo sh      # regular shell
docker exec -ti papiea-mongo mongo   # the mongo shell

Run the application locally

This is a library, so it will be used through an application. Stay tuned for some sample applications!

Run the tests

lein test

License and copyright

Copyright (C) 2018 Nutanix

The code in the public repositories is licensed under the Apache license.

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.