faster web templates
lazarus / 38-Networking and Web Programming

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Blestan · 2012-05-03 08:02

HI All!
After several test and analysis i found that the current
implementation of the templates is not very productive ...
the main issue is that the template file is read and parsed/evaluated 
on every request processing.
my idea is to read the template files only once (or on file date/time
change) .. then make some sort of compiling:

read the file (maybe memory mapped files will be a good alternative to
traditional stream i/o)
find all "tag free" regions in the file and keep a "pointer" to them
find all tags and build a list
find all params and assign them to the tag

on request processing get all tags/params values and build a result
string by concatenation of all "static"parts + "variable" parts;
a better string builder is also a needed ( to avoid multiple memory
reallocs by setlength function)

if some body have similar ideas i will be happy to start a project and
then submit a patch

regards,
blestan

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Leledumbo · 2012-05-03 13:50

Quoteread the file (maybe memory mapped files will be a good
alternative to traditional stream i/o)Hmm... wouldn't this increase
the memory usage? Anyway, the template handling is not that slow,
though there are rooms for improvement. I'd rather suggest changing
the callback mechanism to something like (already done in one of my
projects, but build on top of existing callback mechanism, so it's
actually slower though a bit better IMO. Could be faster if really
implemented):
Code: [Select]MyTemplate := TFPTemplate.Create('template/main.tpl');

Tag := MyTemplate['Name']; // this takes pointer to template named
'Name'
Tag.Value := 'My Name'; // this fills the template replacement

Tag := MyTemplate['Birthdate'];
BirthdateFormat := Tag['Format']; // this takes template argument
named 'Format'
Tag.Value := FormatDateTime(MyBirthdate,BirthdateFormat);

Response.Content := MyTemplate.GetContent; // this builds the final
string