cyberdynesystems/genisys repository overview

⁠genisys

This component is in charge of the compute resource management.

It can scale a service by sending actions to compute backend connectors.

⁠Setup

Install the requirements (assuming you got a Python >= 3.4 devel environment ready):

$ pip install -r requirements.txt

⁠Configuration

The configuration file genisys.yml is written in YAML format⁠.

genisys:
  # Application port
  port: 7001

  # Path to compute definitions
  compute_file: ./computes.py

consul:
  # Consul host
  host: localhost

  # Consul port
  port: 8500

  # Prefix for services managed by genisys
  service_prefix: 'skynet_'

connector:
  # How frequently to poll all connectors for service status
  poll_interval: 15s

⁠Run

Start the component:

$ python genisys.py

⁠Compute definition

To manage computes, genisys provides a simple compute definition format.

It defines a link to a connector that will manage specific compute resources (Docker containers, AWS instances...) associated with a service.

A compute definition looks like:

myCompute = {
	"name": "myCompute",
	"connector": "http://localhost:7051"
}

A compute definition must include a name and a connector.

The connector field is the URL to the genisys connector used to manage compute resources inside this compute.

You can specify an optional file called computes.py at the root of the project and use it to define computes using the format defined above.

⁠HTTP API

Genisys exposes a HTTP API. It can be used to perform CRUD actions on computes and trigger remote procedure calls on services.

Note: The examples use the httpie CLI to query the API, see: https://github.com/jakubroztocil/httpie⁠

⁠compute HTTP endpoint

The following endpoints are exposed:

• /compute⁠ : List compute definitions or register a new compute definition
• /compute/<compute_name>⁠ : Retrieve or update a compute definition

⁠/compute

This endpoint is used to list existing compute definitions or to create a new compute definition.

It supports the following methods: POST and GET.

When hitting the endpoint with a GET, it returns a JSON body like this:

{
  "compute_nameA": {
		"name": "compute_nameA",
		"connector": "http://connector.domain:port",
  },
	"compute_nameB": {
		"name": "compute_nameB",
		"connector": "http://other-connector.domain:port",
  }
}

When hitting the endpoint with a POST, it expects a JSON request body that must look like:

{
	"name": "compute_name",
	"connector": "http://connector.domain:port",
}

All fields are mandatory.

The compute field is used to identify the compute.

The connector field specifies the URL to a genisys connector that will manage the backend.

Example:

$ http POST :7001/compute name="localdc" connector="http://localhost:7051"

⁠/compute/<compute_name>

This endpoint is used to retrieve a compute definition or to update it.

It supports the following methods: PUT and GET.

When hitting the endpoint with a GET, it returns a JSON body like this:

{
    "connector": "http://localhost:7051",
    "name": "localdc"
}

When hitting the endpoint with a PUT, it expects a JSON request body that must look like:

{
	"connector": "http://localhost:7051"
}

The connector field is mandatory.

The connector field specifies the URL to a genisys connector that will manage the backend.

Example:

$ http PUT :7001/compute/local connector="http://localhost:7052"

⁠service HTTP endpoint

The following endpoints are exposed:

• /service/<service_name>/scale⁠ : Ensure that a specific number of compute resource is running for a service.

⁠/service/<service_name>/scale

This endpoint is used to ensure that specific number of compute resources associated to a service are running.

It expects a JSON request body to be POST. The request body must look like:

{
	"number": "number_of_compute_resources",
	"compute": "compute_name"
}

The number field is mandatory.

The compute field is used to identify the compute in which the compute resource will be created. If not specified, genisys will automatically pick up the first compute defined.

Example:

$ http POST :7001/service/myService/scale number=3 compute="local"