Web services processing using MAPI compliant mail applications

A computer storage medium storing computer executable instructions which, when executed by a processor of a server in a distributed environment, perform steps for providing Web Services over a mail transport by utilizing a MAPI (Messaging Application Program Interface) compliant mail application in order to support offline communications and extended processing time of service requests without creating additional infrastructure for such message exchanges, the steps comprising:

• receiving, at a MAPI compliant mail application running on a server that hosts a Web Service, a Web Service message from the Web Service, wherein the Web Service message is received via a custom layered transport that includes a managed MAPI functions layer that is used to convert the Web Service message into an email message that can be sent by the MAPI compliant mail application, wherein the Web Service message is formatted according to an addressing scheme that comprises a transport portion, and an email address portion, wherein the transport portion identifies the use of a MAPI compliant mail application for sending the Web Service message as part of a message exchange pattern between a client and the Web Service that communicate over a mail message transport, and wherein the email address portion defines an email address of the client to which the email message is to be sent, and wherein email messages exchanged between the client and the Web Service are routed through a mail exchange server;
• identifying, at the managed MAPI functions layer, the email address portion within the addressing scheme for sending the Web Service message to the client;
• converting, at the managed MAPI functions layer, the Web Service message into an email message, the email message including the email address of the client, the Web Service message, and an identifier for identifying the Web Service and message exchange type for the Web Service message;
• and
• transferring the email message to an outgoing mailbox of the MAPI compliant mail application for subsequent delivery to the client over the mail message transport such that the email message is stored in the outgoing mailbox until a connection is made to the mail exchange server.

At a computing system in a distributed environment, a method of distributing an NPDL (Network Protocol Description Language) for a Web Service over a mail transport by utilizing a MAPI (Messaging Application Program Interface) compliant mail application in order to support offline communications and generate an NPDL data structure without having to access the Web Service, the method comprising acts of:

• receiving, from a client, a mail message at an incoming mailbox of a MAPI compliant mail application associated with a Web Service, the mail message including a Web Service request message, wherein the mail message is received from an outgoing mailbox of a MAPI compliant mail application and wherein the mail message was stored in the outgoing mailbox until a connection was made to a mail exchange server that routes mail messages between a client and a Web Service, and wherein the Web Service request message is formatted according to an addressing scheme that comprises a transport portion, and an email address portion, wherein the transport portion identifies the use of a MAPI compliant mail application at the client for sending the Web Service request message as part of a message exchange pattern between the client and the Web Service that communicate over a mail message transport, and wherein the email address portion defines an email address of the Web Service;
• transferring the mail message to a custom transports interface that acts as an interface between the MAPI compliant mail application and the Web Service;
• identifying, at the custom transport interface, that the Web Service request message within the mail message is a request for an NPDL data structure by detecting an identifier within the Web Service request message, wherein the NPDL data structure is a specification for describing one or more contracts that an endpoint application complies with when exchanging messages with the Web Service;
• automatically generating the NPDL data structure at the custom transport interface without accessing the Web Service;
• and
• sending the NPDL data structure to the client as part of a return mail message, wherein the return mail message includes an email address for the client, and an identifier for identifying the return mail message as including the NPDL data structure.