Kamailio 4.2 Tips: #6 - Multi-part body management

It was not very common to have SIP messages with multi-part body, but in context of SIP-I/T or instant messaging and presence, or even emergency services, such bodies can occur.

Kamailio 4.2 is a big step forward to simplify the management of multi-part body from configuration file. Textops module introduced three dedicated functions:

• set_body_multipart( [txt, content_type] [, boundary])
• append_body_part(txt, content_type [,  content_disposition])
• remove_body_part(content_type)

All together, they give the option to convert to a multi-part body, set or add a part and remove a part from the body.

Here are some examples:

append_body_part("7e Od 04 55 75 69 20 4d 61 6b 65 43 61 6c 6c",
        "application/vnd.cirpack.isdn-ext",
        "signal;handling=required");

Resulting content in the body is:

...
Content-Type: application/vnd.cirpack.isdn-ext
Content-Disposition: signal;handling=required

7e Od 04 55 75 69 20 4d 61 6b 65 43 61 6c 6c

--unique-boundary-1
...

Removing some part, can be done with:

remove_body_part("application/vnd.cirpack.isdn-ext");

Enjoy it!