We are trying to do a httppost() from SAIL UI and make use by passing parameters

We are trying to do a httppost() from SAIL UI and make use by passing parameters
like Encoding Type and Content-Length. However, the Interface rule hangs on making changes to Content-Length value.Below is the rule snippet

httppost(
"https://documentportalxyz.com",
{},
{},
{"UID","Encoding Type","Content-Length"},
{"ABCDEF","application/x-www-form-urlencoded",10},
"viewer_mode=vertical,application-name=BAIC,domain=EnterpriseBPM,reference-type=APNKEY,reference-number=DL_135_5472,document-list=OS7::{6D057FDF-477E-4663-B27E-A2CFE1D759A1},doctuple-list=555555"
)

How to pass the content-length to appian in SAIL UI
How to get the exact content-length value

OriginalPostID-185962

OriginalPostID-185962