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NHSmail Application Programme Interfaces (APIs)

Application Programme Interface (APIs)

The NHSmail APIs are native Microsoft APIs that provide a bridge to make it possible for you to connect your local, regional, or national applications or services to NHSmail in a self-service manner. This will allow your organisation to increase the benefits of using the platform.

Through APIs, NHSmail is enabling functionality in an open, but controlled and secure manner to enable collaboration in a way that is immediately accessible for in-house innovation within local health and social care organisations as well as third parties.

APIs are not just technical products – they are powerful business tools for developing an ecosystem around the NHSmail platform. However, they do require local technical skills to implement. We have provided links to further Microsoft technical information for the APIs that can be used with the NHSmail service throughout this guidance document. The NHSmail management team reserves the right to restrict users’ access to specific APIs if they are being utilised in a way that is impacting performance of the platform.

When referring to the “NHSmail APIs” throughout this document, this includes Microsoft Exchange and Skype for Business APIs. The NHSmail Exchange and Skype for Business APIs are open-source, although an NHSmail account is needed to access the APIs. NHSmail uses native Microsoft APIs that are transferable to other Exchange or Skype for Business instances. Several web-based platforms and SDKs (software development kits) are available which make it easy to access the APIs and understand how to use them.

See below for high level supporting notes on the recommended APIs that are currently available for NHSmail, as well as links to further information.

Exchange APIs

Exchange Web Services (EWS) has a variety of available APIs that provide access to email and calendar-related functionality that can be integrated into other apps, web-services, and programmes.

Exchange Web Service (EWS) Managed API 2.0

The EWS Managed API is the recommended interface for developing client applications that use EWS and Autodiscover to communicate with Exchange. EWS Managed API is an open-source, simple, and full-featured interface that can be used to work with email messages, calendar, task, and contact information, and to allow programmatic access to mailboxes.

Client applications implementing ‘Managed’ EWS will be compatible with later versions of Exchange including Office365.

For more information refer to

Exchange Web Service (EWS) API

EWS provides a set of operations that client applications use to access and manage Exchange store items. Just like the EWS Managed API, EWS can be used to work with email messages, calendar, task, and contact information, and to allow programmatic access to mailboxes, public folders, and public folder mailboxes. Data is sent to and from the Exchange server by means of XML that is based on a schema definition. Client applications implementing basic EWS will not necessarily be compatible with future releases of Exchange including Office365.

For more information refer to

SOAP Autodiscover

The SOAP Autodiscover service was introduced in Exchange 2010. We recommend that you use the SOAP Autodiscover service to get client configuration data from Exchange. The legacy POX Autodiscover service should not be used and will not be covered in this document.

For more information refer to

Enterprise Directory (LDAP)

The Enterprise Directory (ED) is an implementation of a lightweight directory access protocol (LDAP) service containing full details of the organisations, departments, sites and people registered in the NHSmail service. It is only accessible over Transition Network / HSCN and can be used by any NHSmail subscriber to integrate identity data from the service into local applications and services.

Skype for Business APIs

Skype for Business has two APIs available that provide support for multiple core collaboration services such as presence, chat, audio, and video.

Skype UCWA 2.0

UCWA (Microsoft’s Unified Communications Web API) is a REST API that exposes Skype for Business Server 2015 Instant Messaging and Presence capabilities as well as Audio & Video capabilities. UCWA is language-agnostic – you can choose any programming language to code against it.

For more information refer to:

Skype Web SDK

The Skype Developer Platform for Web (“Skype Web SDK”) is a set of JavaScript Web APIs and HTML controls that enable integration of Skype’s collaboration services with other web-services or applications.

For more information refer to: