They help me...
in Specifying Web Architecture with Larch:
cf discussion with Paul Burchard, circa 1995:
GET : URI -> Literal
e.g.
GET("http://example.com") = "<html><head><title>Example</title> ...</html>"
GET("http://example.com/logo") = ...GIF data...
but... hmm... later, I find
GET("http://example.com/logo") = ...PNG data...
so I've got
GET("http://example.com/logo") != GET("http://example.com/logo")
so how about
GET : URI -> Set[Literal]
e.g.
GET("http://example.com/logo") = {...GIF data..., ...PNG data...}
one day I find:
GET("http://example.com", t1) = {"<html><head><title>Example</title> ...</html>", ...}
and the next:
GET("http://example.com", t2) = {"<html><head><title>Example Company</title> ...</html>", ... }
so how about
GET : URI, Time -> Set[Literal]
but:
... introduces http: absoluteURI, Message, Message, HTTPFormat, HTTPFormat -> Bool % for http(i, q, p, qf, pf) read: % the message q, the request, and the message p, the reply, % constitute a conforming HTTP transaction; the parsed data % in the request and the reply are pf and pf respectively, % and the request URI is i.
http(i, mq, mp, reqData, repData) /\ method(reqData) = GET /\ status(repData) = OK => represents(mp, i, content(repData));
% % If you make a TCP connection to the origin server, whatever % it says is valid/authoritative, as long as its formatted correctly. i.scheme = HTTPURISchemeID /\ account(i) = nil % leave http://user@host/ unspecified for now /\ says(ma, [URIOfDomain(host(i)), RRTypePropertyID(A), lit1]) /\ hostAddr(lit1) = ip1 /\ fresh(ma, mq, TTL(ma)) /\ host(callee(conn(mq))) = ip1 /\ port(callee(conn(mq))) = port(i) /\ conn(mq) = conn(mp) /\ idx(mq) = idx(mp) /\ httpParseReqs(callerBytes(conn(mq)), cmsgs) /\ httpParseReps(calleeBytes(conn(mp)), smsgs) /\ path(cmsgs[idx(mq)]) = i.path /\ host(cmsgs[idx(mq)]) = host(i) % HTTP 1.1-ism => http(i, mq, mp, cmsgs[idx(mq)], cmsgs[idx(mp)]);
Ari Luotonen and Kevin Altis
World-Wide Web
Proxies
Proceedings of the 1st International WWW Conference, May 1994.
http(i, mq, mp, reqData, repData) /\ represents(mp, i, cbody) /\ mp < mq2 /\ http(i, mq2, mp2, reqData2, repData2) /\ method(reqData2) = GET /\ Last_Modified(repData) = If_Modified_Since(reqData2) /\ status(repData2) = NotModified => represents(mp2, i, cbody); % The Conditional GET Axiom, If_None_Match case http(i, mq, mp, reqData, repData) /\ represents(mp, i, cbody) /\ mp < mq2 /\ http(i, mq2, mp2, reqData2, repData2) /\ method(reqData2) = GET /\ ETag(repData) \in If_None_Match(reqData2) % leave * unspecified for now /\ status(repData2) = NotModified /\ ETag(repData2) = ETag(repData) => represents(mp2, i, cbody); % implied metadata?