View source for BaSyx / Documentation / Components

= Components = 
== Off-the-Shelf-Components ==
BaSyx provides several easy to use off-the-shelf components. They can be used programmatically, as an executable jar or as a docker container.
* [[BaSyx_/_Documentation_/_Components_/_AAS_Server | AAS Server Component]]
* [[BaSyx_/_Documentation_/_Components_/_Registry | Registry Component]]
* [[BaSyx_/_Documentation_/_Components_/_DataBridge | DataBridge Component]]
* [[BaSyx_/_Documentation_/_Components_/_AAS_Web_UI| AAS Web UI]]

You can either pull them from Docker Hub or [[BaSyx_/_Documentation_/_Components_/_Docker | follow the instructions ]] to build them yourself.

== Configuring components with environment variables ==
Please see the following page for configuring BaSyx components using environment variables.
* [[BaSyx_/_Documentation_/_Components_/_Environment_Variables | Configuration with environment variables]]

== Security Component ==
Please see [[BaSyx_/_Documentation_/_Components_/_Security_|Security Configuration]] for an overview over different security relevant options with the BaSyx Java SDK.

== CORS Configuration ==
Cross-Origin Resource Sharing (CORS) can be configured to the BaSyx off-the-shelf components.
Please see [[BaSyx_/_Documentation_/_Components_/_Context#CORS_Configuration | CORS Configuration]] for the steps to configure the CORS to the components.

To get to know more about CORS please visit [https://en.wikipedia.org/wiki/Cross-origin_resource_sharing Wikipedia Page about CORS]

== Developing own Components ==
There are multiple ways of implementing BaSys 4.0 conforming components.

=== Extending Existing Interfaces ===
For each component, there exist interfaces that can be implemented to realize e.g. new backends. These interfaces integrate seamless in the REST-API-Provider. Additionally, the already defined test suites for the different component types can easily be reused.

In consequence, this is the easiest and fastest way of introducing new components.

=== Conforming to the REST-API ===
If the interfaces provided by BaSyx can't be used (e.g. because the component is implemented in a programming language currently not supported by BaSyx), it has to be ensured that the component is conforming to the defined REST-API and behavior. 

For this, BaSyx provides a Technology Compatibility Kit (TCK). The TCKs for the components can be found in the repository in ''components/tck''. For each component, there exists a TCK. Each TCK allows to generate a jar file that tests component functionality of arbitrary http endpoints.
Each jar can be called in the following way:
 java -jar $JAR $HTTP_ENDPOINT
where ''$JAR'' is the name of the component's TCK jar and ''$HTTP_ENDPOINT'' is the endpoint on which the component's REST API is available.