Program: Processing a Simple MIME Message

SourcePro Net : Internet Protocols Module User’s Guide : PART II Packages of the Internet Protocols Module : Using the MIME Package : Program: Processing a Simple MIME Message

Example 30 uses the MIME package to process a simple MIME message and print the components of the message to standard output. The message processed is essentially identical to the message generated in Example 28, Creating a simple MIME message. We’ve taken shortcuts to keep the example simple. A production application would normally check to make sure that the message received is actually a simple MIME message before processing the message (see Process the Body). Source for this program is in BasicMimeMessageDecomposition.cpp in the examples\mime directory.

NOTE: 	Sample programs are located in the examples directory created for your installation. For more information, see Installing and Building Your SourcePro Products and Building Your Applications.

Example 30 – Processing a simple MIME message

#include <rw/mime/RWMimePart.h>

#include <iostream>

using std::cout;

using std::cerr;

using std::endl;

// This is roughly equivalent to the message generated in

// the BasicMimeMessageComposition example.

const RWCString messageStr(

"MIME-Version: 1.0\r\n"

"To: <developer@yourcompany.com>\r\n"

"From: <developer@roguewave.com>\r\n"

"Subject: Sample MIME Message from Rogue Wave\r\n"

"Content-Type: text/plain\r\n"

"\r\n"

"This is a simple MIME Message generated with the\r\n"

"Internet Protocols Module of SourcePro Net.\r\n"); //1

int main(void)

{

// Create a RWMimePart object.

RWMimePart message; //2

// extract the message from the string.

message.fromString(messageStr); //3

cout << "MIME Message Extraction" << endl << endl;

// Show header information for the message.

cout << "...Headers" << endl << endl;

for (size_t pos = 0; pos < message.getHeaderCount(); ++pos) //4

{

RWMimeHeader header = message.getHeader(pos); //5

cout << header.asString() << endl; //6

}

// Display the body of the message. Normally, you would

// convert line delimiters into local form for your OS

// before displaying a text body. But for this example,

// we'll just print it out in canonical form.

  cout << endl << "...Body" << endl << endl << message.getBody()         << endl;                                                //7

return 0;

}

//1 Defines the message as a constant string to keep the example short. A production application would obtain the message from outside the program.

//2 Creates an empty RWMimePart.

//3 Populates the part with the contents of messageStr. In a production application, the call to fromString() would be enclosed in a try block. We’ve left out the try block since the example uses a constant string.

//4 The for loop on this line increments pos to index each header in the message. To find a specific header, you could also use the findHeader() function of RWMimePart.

//5 Retrieves the header at position pos.

//6 Prints the header label and the header value to standard output.

//7 Prints the message body to standard output. This command prints the message body exactly as the body appears in the MIME message. A production application would typically decode the body and convert the body from canonical text before displaying the body or processing the body further.

This program generates the following output:

MIME Message Extraction

...Headers

MIME-Version: 1.0

To: <developer@yourcompany.com>

From: <developer@roguewave.com>

Subject: Sample MIME Message from Rogue Wave

Content-Type: text/plain

...Body

This is a simple MIME Message generated with the

Internet Protocols Module of SourcePro Net.