Plan: a web server. (This is not Scheme.)

gistfile1.scm

(set! default-headers* '{content-type "text/html; charset=utf-8"
                         server "Plan httpd"})
;; OHSHI-
(set! response-codes* '{100 "Continue"       ; 100-199 -- informational
                        101 "Switching Protocols"
                        102 "Processing"
                        
                        200 "OK"             ; 200-299 -- success
                        201 "Created"
                        202 "Accepted"
                        203 "Non-Authoritative Information"
                        204 "No Content"
                        205 "Reset Content"
                        206 "Partial Content"
                        207 "Multi-Status"
                        
                        300 "Multiple Choices" ; 300-399 -- redirection
                        301 "Moved Permanently"
                        302 "Found"
                        303 "See Other"
                        304 "Not Modified"
                        305 "Use Proxy"
                        306 "Switch Proxy"
                        307 "Temporary Redirect"
                        
                        400 "Bad Request"    ; 400-499 -- client error
                        401 "Unauthorized"
                        402 "Payment Required"
                        403 "Forbidden"
                        404 "Not Found"
                        405 "Method Not Allowed"
                        406 "Not Acceptable"
                        407 "Proxy Authentication Required"
                        408 "Request Timeout"
                        409 "Conflict"
                        410 "Gone"
                        411 "Length Required"
                        412 "Precondition Failed"
                        413 "Request Entity Too Large"
                        414 "Request-URI Too Long"
                        415 "Unsupported Media Type"
                        416 "Requested Range Not Satisfiable"
                        417 "Expectation Failed"
                        418 "I'm a teapot" ; srsly
                        422 "Unprocessable Entity"
                        423 "Locked"
                        424 "Failed Dependency"
                        425 "Unordered Collection"
                        426 "Upgrade Required"
                        
                        500 "Internal Server Error" ; 500-599 -- server made a boo-boo
                        501 "Not Implemented"
                        502 "Bad Gateway"
                        503 "Service Unavailable"
                        504 "Gateway Timeout"
                        505 "HTTP Version Not Supported"
                        506 "Variant Also Negotiates"
                        507 "Insufficient Storage"
                        510 "Not Extended" })


(deffn (http-server host port request-handler)
  (let sock (socket 'inet 'stream)
    (bind sock host port)
    (listen sock 5)
    
    ((rfn (inthandl conninfo)
      (let conn (car conninfo)
        (let rql (read-request-line conn)
          (request-handler
            {'method (car rql)
             'uri (cadr rql)
             'http-version (caddr rql)
             'headers (read-headers conn)
             'ip (cadr conninfo)
             'port (caddr conninfo)
             'stream conn}
            
            (responder conn))) (inthandl (accept sock)))) (accept sock))))

(deffn (responder conn)
  (fn (resp)        
    (if (string? resp)
          (send-response 200 default-headers* resp)
        (and (list? resp) (= (length resp) 2))
          (send-response (car resp) default-headers* (cadr resp))
        (and (list? resp) (= (length resp) 3))
          (send-response (car resp) (dictionary-merge (cadr resp) default-headers*) (caddr resp)))))

(deffn (send-response conn status headers body)
  (printrn conn "HTTP/1.1 " status " " (response-codes* status))
  (each header (dictionary->alist headers)
    (printrn conn (car header) ": " (cadr header)))
  (printrn conn)
  (printrn conn body)
  (close conn))

(deffn (read-request-line conn)
  (let line (regexp-match (strip (gets conn)) r{^(\w+) (.*) HTTP/(\d\.\d)$}i)
    (list (symbol (line 1)) (line 2) (line 3))))

(deffn (read-headers conn)
  ((rfn (reader headers ln)
      (if (= "" ln) headers
        (let parts (regexp-match ln /^(.+?): (.*)$/)
          (set (headers (symbol (parts 1))) (parts 2))
          (reader headers (strip (gets conn)))))) {} (strip (gets conn))))