When making an HTTP client request in CICS® Web support, you must open a connection
to the server before sending the first request. CICS returns a session token that represents
the connection.
Initiate a connection with the server by issuing a WEB OPEN command
as follows:
- Specify the host name of the server, the length of the host name,
and the scheme that is to be used (HTTP or HTTPS). Also specify
the port number for the host if this is other than the default for the specified
scheme. You can specify the URIMAP option on the WEB OPEN command
to use this information directly from an existing URIMAP definition. Alternatively, you can supply the information using
the SCHEME, HOST, HOSTLENGTH and PORTNUMBER options. You can extract these
details from a known URL using the WEB PARSE URL command, or from an existing
URIMAP definition using the WEB EXTRACT URIMAP command.
- If required, specify the CODEPAGE option to change the EBCDIC code
page for this connection to something other than the default code page for
the local CICS region
(set by the LOCALCCSID system initialization parameter). This might be the
EBCDIC code page for another national language. When the server
returns its response, if conversion is specified, CICS converts the response body into this
code page before passing it to the application.
- If you are using the HTTPS scheme, specify appropriate security
options:
- If you need to supply an SSL client certificate, specify the
CERTIFICATE option to do this. If you specify the URIMAP option
on the WEB OPEN command, you can use this information directly from an existing
URIMAP definition.
- Use the CIPHERS and NUMCIPHERS options to specify a list of
cipher suite codes to be used for the connection. If you specify
the URIMAP option on the WEB OPEN command, you can either accept the setting
from the URIMAP definition, or specify your own list of cipher suite codes
to override the URIMAP specification.
- The WEB OPEN command drives the XWBOPEN user exit. You can create
a user exit program to make the connection to the server go through a proxy
server, or to apply a security policy to a host name, if required. HTTP client open exit XWBOPEN has information to help
you do this.
CICS opens
the connection with the server, and returns a session token to the application
program. CICS also
returns information on the HTTP version of the server.
Save the session token and use it on all subsequent commands that
relate to this connection.