Using the SOAP API endpoints in ArcGIS Server is deprecated. The existing SOAP API continues to be supported but will receive no future enhancements or updates. There are no current plans to remove SOAP API support entirely, but any new development should be based on the REST API and higher-level APIs and SDKs that consume REST endpoints.
Note: This deprecation notice was originally published September 2019 and is being republished to aid discoverability and continued awareness.
Existing applications that make use of the SOAP API are encouraged to move to the REST API endpoints as part of future maintenance and enhancements.