Reply To: Calling a web service from tcl.

March 24, 2006 at 3:42 pm #58593

Mike Shoemaker

Participant

Hey Todd,

Here is the package that connects and sends data to a webservice. Basically, you call this with 3 parameters:

inData is the data (string) to be sent to the webservice

inUrl is the url of the webservice

inParam is the parameter used in the url of the webservice.

The statement set query2 [::http::formatQuery $queryParam $xml_data] will gather the data string and the parameter and format a query sting.

The statment set http [::http::geturl $url -query $query2] will do the work basically and post the data to the url supplied using the properly formated query created in the statement above.

The rest of the code is for handling the responses. There are 2 types, the HTTP response which is from the web server (an example is a 404 not found error when requesting a page) and the HTML error which is the response from the webservice code (this is where your xml response would be)



Code:


package require http

package require WebServiceAckNak
proc webServiceConn { inData inUrl inParam } {
  set html “”

  set url $inUrl

  set xml_data $inData

  set queryParam $inParam
  set query2 [::http::formatQuery $queryParam $xml_data]
  if {![catch {set http [::http::geturl $url -query $query2]} error_msg ]} {
    set html [::http::data $http]
    upvar #0 $http status
      foreach index [array names status] {
        switch -exact — $index {

          querylength { set query_len [array get status $index] }

          currentsize { set response_len [array get status $index] }

          http { set http_status [array get status $index] }

          default { }

        }

      }
    set http_status [lindex $http_status 1]

  

        set ackNak [webServiceAckNak $http_status $html]
        return $ackNak  
  } else {
    echo “error has been encountered::$error_msg”
  }
        if {$html != “”} {

          [::http::cleanup $html]

        }

}

The second package i have handles the server and html responsed.



Code:


proc webServiceAckNak { inHTTP inHTML } {
  set result “”
  set httpResponse $inHTTP

  set htmlResponse $inHTML
    set htmlResponseString [lindex [split $htmlResponse n] 1]
      regexp >(.*?) $htmlResponseString match result
        if {$result == “working”} {
          return 0

        

        } else {
          echo $htmlResponse

          echo $httpResponse
        }
}

To configure this in the engine, i use a raw route for the messages i want to send and configure the proc on the outbound tps. The outbound tps proc contains all the translation for the message and then at the end i call the webservice proc as:



Code:




set res [webServiceConn $msg $url $queryParameter]

  if {$res == 0} {

    set status_cond 1

    echo “Message Sent Successfully.”

  } else {

    set status_cond 0

   echo “An error has been encountered with the webservice connection. Retrying…COUNT: $counter”

  }

Let me know if you need more details with the code, i’m happy to help.

Have fun!

Mike