Mod ssi » History » Revision 19
Revision 18 (lonnyk, 2012-08-11 10:42) → Revision 19/28 (frb, 2012-10-01 19:50)
h1. Server-Side Includes
{{>toc}}
*Module: mod_ssi*
h2. Description
SSI is a very old and cheap way to generate content dynamically on server-side.
The use of this module is strongly discouraged:
* the execution of a SSI script is done in the server-core
* a long-running SSI script blocks the handling of ALL connections
* as soon as you use #exec the performance gets worse than using CGI scripts directly
You should only use SSI for two reason:
* content assembling with #include
* legacy applications
h2. Configuration
You have to load the mod_ssi module and set the ssi-extension:
<pre>
server.modules = ( ..., "mod_ssi", ... ) #Note that if you use mod_compress mod_ssi must come first to function.
ssi.extension = ( ".shtml" )
</pre>
h2. Supported Options
<pre>
<!--#echo var="..." -->
<!--#echo var="DOCUMENT_ROOT"-->
<!--#include file="..."\|virtual="..." -->
<!--#flastmod file="..."\|virtual="..." -->
<!--#fsize file="..."\|virtual="..." -->
<!--#config timefmt="..." sizefmt="(bytes|abbrev)" -->
<!--#printenv -->
<!--#set var="..." value="..." -->
<!--#if expr="..." -->
<!--#elif expr="..." -->
<!--#else -->
<!--#endif -->
<!--#exec cmd="..." -->
<!--#exec cmd="date"-->
</pre>
h2. Expression Handling
Every "expr" is interpreted:
* logical: AND, OR, !
* compare: =, <, <=, >, =>, !=
* precedence: (, )
* quoted strings: 'string with a dollar: $FOO'
* variable substitution: $REMOTE_ADDR
* unquoted strings: string
h2. Flow Control
if, elif, else and endif can only be used to insert content under special conditions.
h2. Unsupported Features
The original SSI module from NCSA and Apache provided some more options which are not supported by this module for various reasons:
* nested requests with `include virtual`: use exec to execute scripts or apply the patch at http://trac.lighttpd.net/trac/ticket/536
* `echo var` for SSI variables: it only works for environment variables if you don't apply patch at http://trac.lighttpd.net/trac/ticket/795
* config.errmsg
* echo.encoding