Re: [Tclhttpd-users] example for chunked data sending?

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David Gravereaux wrote:
> I want to do some experiments with sending an unending page and I need
> to send parts of it at a time delaying through the event loop.  I looked
> at Httpd_ReturnFile and it's similar to what I want to do, but I won't
> be using [fcopy], of course.
> 
> Is there such a procedure that I missed spotting?

Success of the DIY kind..

Attached are some procedures to do chunked data sending for domain
handlers in replace of Httpd_ReturnData.

It works:
http://www.pobox.com/~davygrvy/chat

That plays back an IRC log at triple speed and takes a few minutes to
complete.

A short example of its use would be the following.  Notice that I use
Httpd_ReturnDataChunkHeader in replace of Httpd_ReturnFile and that the
callback script [ChatChunkHandler] sends a "chunk" at a time delaying
through the event loop (non-blocking delay) until finished.

 Url_PrefixInstall /chat [list Chat /chat] -thread 1
 set ChatDir [file dirname [info script]]

 proc Chat {prefix sock suffix} {
    global ChatDir
    upvar #0 Httpd$sock data

    # open the replay file and store it in the connection object.
    set f [open [file join $ChatDir datanew.txt]]
    fconfigure $f -encoding utf-8
    set raw [read $f]
    close $f
    set data(chatLines) [split $raw \n]

    # get page html <head> block with opening <body>
    set firstChunk [ChatGetHeadStuff]

    # process first chat line
    foreach {delay line} [split [lindex $data(chatLines) 0] \t] {}
    set data(chatLines) [lreplace $data(chatLines) 0 0]
    append firstChunk $line

    Httpd_ReturnDataChunkHeader $sock text/html $firstChunk ChatChunkHandler
 }

 proc ChatChunkHandler {sock} {
    upvar #0 Httpd$sock data

    set delay 0
    set line ""

    # process next chat line
    foreach {delay line} [split [lindex $data(chatLines) 0] \t] {}
    set data(chatLines) [lreplace $data(chatLines) 0 0]

    set delay [expr {int($delay/3.0)}]

    if {[llength $data(chatLines)] != 0} {
    	after $delay [list Httpd_ReturnDataChunkBody $sock $line
ChatChunkHandler]
    } else {
	unset data(chatLines)
    	after $delay [list Httpd_ReturnDataChunkLast $sock $line]
    }
 }

 proc ChatGetHeadStuff {} {
    return {<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01
Transitional//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
    <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=utf-8">
    <META NAME="Generator" CONTENT="IRC_Engine">
    <TITLE>Live on Internet Relay Chat</TITLE>
    <style type="text/css">
    .....
    </style>
</head>
<body text="#C0C0C0" bgcolor="#000000">
 }
 }

Re: [Tclhttpd-users] example for chunked data sending?

TclHttpd is a Web server implemented in pure Tcl.

Re: [Tclhttpd-users] example for chunked data sending?