Xpanse is an Open Source project allowing to easily implement native managed service on any cloud service provider. This project is part of the Open Services Cloud (OSC) charter.

Xpanse unleashes your cloud services by removing vendor lock-in and lock out. It standardizes and exposes cloud service providers core services, meaning that your xpanse service is portable (multi-cloud) on any cloud topology and provider. It also avoids tight coupling of your service to other cloud service provider services.

Configuration Language

A managed service is described using Open Services Cloud Configuration Language (OCL).

OCL is a yaml descriptor of a managed service, describing the expected final state of your service, interacting with the fundamental APIs:

Examples of managed services described using OCL for multiple clouds can be found here.

Deployment Scripts

In OCL, the deployer variable can contain the script that must be executed for provisioning the managed service. Currently, the only allowed script is Terraform.

Flavors

For each managed service, we can define different flavors of it. For example, different sizes of the VM, etc. End user can then select the flavor of their preference for the service while ordering.

Flavor properties

Flavors can have properties which can be simply declared and referred in the deployment script too with the same property names. Runtime wil ensure tht these variables are automatically available for the deployment scripts

Deployment Variables

As part of the OCL, the managed service provider can define variables that can be either entered by the user or available as defaults. All possible types of variables are defined here Deployment Variables The variables can then be used in the deployment scripts.

OCL loading

Xpanse provides different options to generate and provision OCL:

• REST API on the xpanse runtime
• Xpanse UI

Orchestrator & Binding

OCL descriptor is an abstract description of the final managed service state. It's generic enough to work with any cloud service provider.

Xpanse runtime embeds an orchestrator responsible to delegate the services management to plugins.

Each plugin is dedicated to handle a cloud provider infrastructure and do actions required to actually deal with the services' lifecycle:

1. to bind OCL to the concrete cloud provider internal APIs
2. to generate the graph of actions required to reach the final expected state, specifically for a target cloud provider

Plugin Activation

A plugin for a cloud provider is activated by default. But a plugin might need one or more mandatory configuration available for it to work. These mandatory configuration properties must be declared when the plugins are implemented. If any of the required configuration properties is not available, then such plugin is simply not considered for processing any requests.

Openstack

Mandatory configuration properties are the following -

• OS_AUTH_URL - Keystone URL of the Openstack installation.

Other optional config properties

• OS_SERVICE_PROJECT - Openstack project to be used to get monitoring information. All metrics data is stored in a different central project. If this is not provided, then the project where the resource is hosted is used to get the metrics data.
• OS_PROXY_HOST and OS_PROXY_PORT - Proxy server information to reach the Openstack installation.

HuaweiCloud

No mandatory configuration properties required.

FlexibleEngine

No mandatory configuration properties required.

Runtime

Xpanse runtime is the overall component running on the cloud provider.

The runtime embeds and run together:

1. the orchestrator with the different bindings
2. the OCL loader and parser
3. the frontends (REST API, ...)

Database

The default database attached to the runtime is the H2 in-memory database. The same can be replaced with other production ready database systems by replacing the configurations mentioned below and by adding relevant maven dependencies.

spring.datasource.url=jdbc:h2:mem:testdb
spring.datasource.driverClassName=org.h2.Driver
spring.datasource.username=sa
spring.datasource.password=

spring.jpa.show-sql=false
spring.jpa.properties.hibernate.dialect=org.hibernate.dialect.H2Dialect
spring.jpa.hibernate.ddl-auto= update

Build and Package

First, you can build the whole xpanse project, including all modules (orchestrator, OCL, runtime, plugins, etc), simply with:

$ mvn clean install

Run

By default, the application will not activate any plugins. They must be activated via spring profiles. Also ensure that only one plugin is active at a time. For example, openstack plugin can be activated as below

$ cd runtime/target
$ java -jar xpanse-runtime-1.0.0-SNAPSHOT.jar -Dspring.profiles.active=openstack

By default, the runtime is built in "exploded mode". Additionally, you can also build a Docker image adding -Ddocker.skip=false as build argument:

$ cd runtime
$ mvn clean install -Ddocker.skip=false

We can start xpanse runtime with a specific plugin by passing the plugin name in the profile name. For example to start openstack

$ docker run -e "SPRING_PROFILES_ACTIVE=openstack" --name my-xpanse-runtime xpanse

Static Code Analysis using CheckStyle

This project using CheckStyle framework to perform static code analysis. The configuration can be found in CheckStyle. The framework also checks the code format in accordance to Google Java Format.

The same file can also be imported in IDE CheckStyle plugins to get the analysis results directly in IDE and also to perform code formatting directly in IDE.

The framework is added as a maven plugin and is executed by default as part of the verify phase. Any violations will result in build failure.

License/Copyright Configuration

All files in the repository must contain a license header in the format mentioned in License Header.

The static code analysis framework will also validate if the license exists in the specified format.