On Mar 22, 2013, at 5:06 AM, Jay McCarthy wrote: > I'm willing to change the docs, but I'd like to try to explain it in > an email to make sure the explanation is okay. > > The key sentence of the documentation is: "start is loaded as a > servlet and responds to requests that match servlet-regexp." > > The default for servlet-regexp is such that the ONLY path that the > servlet responds to is "/servlets/standalone.rkt" and ALL other paths > are handled by the static file handlers.
I think that that fact is not inferrable from the docs. I would change the current text to: "start is loaded as a servlet and responds to requests that match servlet-regexp. Requests that don't match this regexp will be served from the pool of static files, if a corresponding file exists, or routed to the file-not-found-responder." Reviewing my thrashing last night, I've come to the conclusion that much of my suffering was caused by browser caching. I think that the text above might have gotten me to that realization, by explicitly static a set of circumstances under which requests go to the pool of static files. Thoughts? John > The key sentence of the documentation is: "start is loaded as a > servlet and responds to requests that match servlet-regexp." > > It is common to change the servlet-regexp to something like #rx"", > which causes ALL requests to be handled by the servlet. When you do > this, the documentation is still correct, but you may not realize the > consequence of what you've done. > > Throughout the Web server infrastructure, and serve/servlet does not > change this, if you call (next-dispatcher) then the current responder > FAILS and the next responder gets a chance. In the context of > serve/servlet, if you call (next-dispatcher) after using #rx"" to take > over all requests, then for that particular request where > (next-dispatcher) was dynamically called, the static handlers take > over. > > It so happens that the default "else" clause in web-server/dispatch is > to call (next-dispatcher). From the documentation: "If else-fun is > left out, one is provided that calls (next-dispatcher) to signal to > the Web Server that this dispatcher does not apply." > > Thus, if you use the #rx"" regexp AND dispatch-rules, then it is > likely that the "right" thing will happen without you trying because > you won't write an else and then if your servlet doesn't handle the > request, the static handler will be in control. > > Overall, I don't know what the documentation should be changed to say. > All this is in the documentation right now: you just might not realize > you are telling the servlet to handle everything, but once you realize > that you just need to know how to turn that off, and that isn't > specific in any way to serve/servlet, so I don't feel like it is > appropriate to put it there. (Alternatively, you should just be more > specific in your servlet-regexp, by using something like > (re-complement #rx"/static/.+"), and that's reasonable to expect a > user to realize, IMHO.) > > Jay > > > On Thu, Mar 21, 2013 at 10:55 PM, John Clements > <[email protected]> wrote: >> The serve/servlet function has several flags that allude to the ability to >> serve static files (#:extra-files-paths, etc.). However, nowhere in that >> documentation does it say under what circumstances the web-server serves >> content from that pool of files. After much struggling and cursing, I >> finally found a post by Matt Jadud. Even then, it took me quite a while to >> realize that the 'dispatch-rules' function was the key to actually allowing >> some requests to reach the static content. Perhaps the serve/servlet >> documentation should explicitly specify when content is served from static >> files, or at least provide a pointer to the dispatch-rules documentation. >> >> Thoughts? >> >> John >> >> >> ____________________ >> Racket Users list: >> http://lists.racket-lang.org/users > > > > -- > Jay McCarthy <[email protected]> > Assistant Professor / Brigham Young University > http://faculty.cs.byu.edu/~jay > > "The glory of God is Intelligence" - D&C 93 > > ____________________ > Racket Users list: > http://lists.racket-lang.org/users ____________________ Racket Users list: http://lists.racket-lang.org/users
