View source for BaSyx / Documentation / VAB / JSON Serialization

{| class="wikitable"
! style="text-align:left;"| See also
| [[BaSyx_/_Documentation_/_VAB_/_HTTP_Mapping | HTTP/REST Mapping]]
| [[BaSyx_/_Documentation_/_VAB_/_TCP_Mapping | TCP Mapping]]
| [[BaSyx_/_Documentation_/_VAB_/_Exceptions | Exceptions]]
|}
= JSON Serialization =
Both the TCP and the HTTP mapping use a json serialization for objects send over the VAB. In the following, this json serialization is explained.
== Requirements ==
There are multiple requirements on the JSON serialization:
* Preserve type information, since JSON only knows a small set of [https://www.w3schools.com/js/js_json_datatypes.asp types]
* Be compatible to the JSON serialization defined in [https://www.zvei.org/en/subjects/industrie-4-0/details-of-the-asset-administration-shell/ Details of the Asset Administration Shell]
* Be compatible to the C#-SDK since it is not using the VAB


== Type Representation ==
The following types are taken ''as is'' from the JSON type scheme:
*string
*number (integer or double)
*object (i.e. map)
*boolean
*null

Additionally, these types are introduced:
*ordered lists
*functions

=== Functions ===
Functions are most commonly not serializable. Exception of this are Java functions, that can be represented by their byte code. 
However, there still needs to be an indication that a value is representing a function. This is done by passing this information in the ''_basyxFunctionType'' key.
The allowed values are:
* lambda
* operation