$Web Response: Difference between revisions
m (1 revision) |
mNo edit summary |
||
| Line 2: | Line 2: | ||
<span class="pageSubtitle"><section begin="desc" />Set HTTP response header parameter<section end="desc" /></span> | <span class="pageSubtitle"><section begin="desc" />Set HTTP response header parameter<section end="desc" /></span> | ||
$Web_Response can be used to set any HTTP response header parameter. | |||
$Web_Response is a [[Calling_Sirius_Mods_$functions|callable]] $function, and it takes two arguments and returns a numeric status code. | |||
==Syntax== | ==Syntax== | ||
<p class="syntax"><section begin="syntax" /> %RC = $Web_Response( parameter, value ) | <p class="syntax"><section begin="syntax" /> %RC = $Web_Response( parameter, value ) | ||
<section end="syntax" /></p> | <section end="syntax" /></p> | ||
===Syntax terms=== | |||
<table class="syntaxTable"> | <table class="syntaxTable"> | ||
<tr><th> | <tr><th>%rc</th> | ||
<td> | <td>A numeric variable to contain a return code. Possible values are: | ||
<table class="syntaxTable"> | <table class="syntaxTable"> | ||
<tr><th>0</th> | <tr><th>0</th> | ||
<td>Response header parameter set.</td></tr> | <td>Response header parameter set.</td></tr> | ||
| Line 26: | Line 20: | ||
<td>Not a web thread</td></tr> | <td>Not a web thread</td></tr> | ||
<tr><th>-5</th> | <tr><th>-5</th> | ||
<td>Parameter name missing.</td></tr> | <td>Parameter name missing.</td></tr></table> | ||
</table | |||
<tr><th>parameter</th> | |||
<td>The name of the HTTP response header parameter.</td></tr> | |||
<tr><th>value</th> | |||
<td>The value of the HTTP response header parameter. | |||
</td></tr></table> | |||
==Usage notes== | |||
Most response header parameters are set "under-the-covers" either automatically or as the result of other ''[[Janus Web Server]]'' $function calls. These automatically set parameters should be adequate for most applications. In the cases where they're not, $Web_Response provides the ability to set response header parameters directly. | Most response header parameters are set "under-the-covers" either automatically or as the result of other ''[[Janus Web Server]]'' $function calls. These automatically set parameters should be adequate for most applications. In the cases where they're not, $Web_Response provides the ability to set response header parameters directly. | ||
The response header parameter that is most likely to be useful and that can only be set with $Web_Response is the "Pragma" parameter which can be used to indicate that a response should not be cached by the browser as in the following example. | The response header parameter that is most likely to be useful and that can only be set with $Web_Response is the "Pragma" parameter which can be used to indicate that a response should not be cached by the browser as in the following example. | ||
| Line 38: | Line 35: | ||
The response header parameters are not sent until the size of the response has been determined, either as the result of a <var>$Web_Done</var> or a $Web_ProcSend. Until one of these is issued, it is possible to change the value of a response header parameter at will. | The response header parameters are not sent until the size of the response has been determined, either as the result of a <var>$Web_Done</var> or a $Web_ProcSend. Until one of these is issued, it is possible to change the value of a response header parameter at will. | ||
Extreme caution should be used with this function since it provides direct access to the HTTP layer of the web protocols. $Web_Response does '''no''' validity checking for the parameter name or value specified. For more information about the HTTP protocol including a specification of all the standard response header parameters, visit | Extreme caution should be used with this function since it provides direct access to the HTTP layer of the web protocols. $Web_Response does '''no''' validity checking for the parameter name or value specified. For more information about the HTTP protocol including a specification of all the standard response header parameters, visit http://www.ics.uci.edu/pub/ietf/http/. | ||
[[Category:Janus Web Server $functions|$Web_Response]] | [[Category:Janus Web Server $functions|$Web_Response]] | ||
Revision as of 19:57, 6 June 2012
<section begin="desc" />Set HTTP response header parameter<section end="desc" />
$Web_Response can be used to set any HTTP response header parameter.
$Web_Response is a callable $function, and it takes two arguments and returns a numeric status code.
Syntax
<section begin="syntax" /> %RC = $Web_Response( parameter, value ) <section end="syntax" />
Syntax terms
| %rc | A numeric variable to contain a return code. Possible values are:
| ||||||
|---|---|---|---|---|---|---|---|
| parameter | The name of the HTTP response header parameter. | ||||||
| value | The value of the HTTP response header parameter. |
Usage notes
Most response header parameters are set "under-the-covers" either automatically or as the result of other Janus Web Server $function calls. These automatically set parameters should be adequate for most applications. In the cases where they're not, $Web_Response provides the ability to set response header parameters directly. The response header parameter that is most likely to be useful and that can only be set with $Web_Response is the "Pragma" parameter which can be used to indicate that a response should not be cached by the browser as in the following example.
%RC = $Web_Response('Pragma', 'no-cache')
The response header parameters are not sent until the size of the response has been determined, either as the result of a $Web_Done or a $Web_ProcSend. Until one of these is issued, it is possible to change the value of a response header parameter at will.
Extreme caution should be used with this function since it provides direct access to the HTTP layer of the web protocols. $Web_Response does no validity checking for the parameter name or value specified. For more information about the HTTP protocol including a specification of all the standard response header parameters, visit http://www.ics.uci.edu/pub/ietf/http/.