Progress
Version 9
Product Update Bulletin
Using the AppServer Internet Adapter With HTTP
When using HTTP, all requests between the client and the AppServer (or SonicMQ Adapter) go through a Web server that forwards each request to the AppServer. Depending on the client type, an AppServer client indicates that Progress must use HTTP tunneling as follows:
- For a 4GL client (including the WebClient) that connects to the AppServer, the client uses the
-URL
connection parameter on theCONNECT( )
method of the server handle to specify a URL with an HTTP protocol.- For an Open Client, you specify the URL in the AppObject Proxy object that you can create with
ProxyGen
.- For a 4GL client of the SonicMQ Adapter, you specify the URL as a parameter to a 4GL connection procedure.
The URL contains the host and port of the Web server, the path to the AIA instance, as well as the requested application service. For information about how a Progress client connects using the AIA, see the "Connecting from Progress Clients Using the AIA" section.
Each AIA instance can either connect directly to an AppServer or use a controlling NameServer to connect. How the connection is made is specified when you configure the AIA instance. Each request sent from an AppServer client to the Web server is encapsulated within one or more standard HTTP POST requests. The URL contained within the POST request indicates to the Web server that it should forward the request to AIA.
When the AIA instance receives the connection request from an AppServer or SonicMQ Adapter client, the requested application service name is included along with the
userid
,password
, andappserver-info
values that are normally passed in a connection request to an AppServer. AIA then passes the application service name either to the controlling NameServer and the NameServer passes the request to the AppServer, or AIA passes the request directly to the AppServer. For more information, see the "Administering and Configuring an AppServer Internet Adapter" section.NOTE: Because the HTTP protocol is connectionless, the AppServer can never determine from the client’s connection state if the AppServer client’s connection should be terminated. Because of failures at the client site, as well as the network between the client site and the Web server, it is possible that an AppServer client could connect to an AppServer and never gracefully disconnect. To guard against the possibility of an AIA instance maintaining orphaned connections, you can use theidleConnectionTimeout
property in theubroker.properties
file to configure an AIA instance to automatically terminate the connection if a connection is idle for more than the specified time. For more information, see the "Administering and Configuring an AppServer Internet Adapter" section.Supported Client Platforms
For the following clients, HTTP is supported on these platforms:
Supported Server Platforms
On server machines, you can use any Web server that supports HTTP. For more information, see the "Installing and Configuring Web Servers and Java Servlet Engines" section.
Copyright © 2004 Progress Software Corporation www.progress.com Voice: (781) 280-4000 Fax: (781) 280-4095 |