rewriteUrl

The picoLisp built-in web server follows specific url conventions. Sometimes, it is useful to:

1. have url format under control, i.e. having custom & "nice" application specific urls
2. allow and collect any query parameters automatically

The following code shows a sample web server which servers files from @public_html/ directory (relative to picoLisp home, which is not a problem as you can always create a symlink), e.g. http://localhost:8080/index.html is served from @public_html/index.html file.

(load "ext.l" "lib/http.l")

(de rewriteUrl (U)
   (chop (pack "public_html/" U)) )

# I'd recommend the following version of 'rewriteUrl'.
# It avoids the 'chop' following a 'pack' by using a constant
# pre-chopped "public..".
#
# (de rewriteUrl (U)
#    (append '`(chop "public_html/") (chop U)) )

(patch http
   '(if (<> *ConId *SesId) @X)
   (append '(if (<> *ConId *SesId))
      (list (car @X))
      (list '(setq @U (rewriteUrl @U)))
      (cdr @X) ) )

(redef http @
   (off *HtVars)
   (pass http) )

(redef _htSet @
   (push '*HtVars (cons (pack (next)) (next))) )

(allowed (&qrlog: can't exec
uot;public_html/") "@start")

(de start ()
   (html 0 "Hello" NIL NIL
      "Hello World!" ) )

(server 8080 "@start")

Note that @start is never called but it could be if we used a more sophisticated rewriting function.

ToDo SSI