August 2005 - tbnl-devel@common-lisp.net - mailman3.common-lisp.net

[tbnl-devel] tbnl freeze
by Steve Huffman 30 Apr '06

30 Apr '06

Hi all, I'm working on reddit.com, which uses TBNL as its web framework. For the most part, all is well, but I've been running into an error lately that is causing me to worry. Basically, the symptom of the problem is that our website appears to pause, and all requests just hang (eventually they'll timeout on the browser side). I work against our server using remote SLIME. The SLIME session does not hang, but in order to bring the website back to life I log into our web server, use attachtty to view the running lisp process, and hit ctrl + c a few times, after which a debugger will pop open in Emacs that I can abort. I'm running CMUCL 19a on a FreeBSD box. I use apache and mod_lisp in front of TBNL. I haven't been able to find out what causes this lockup, nor do I understand why I must open the process on the web server (when I'm already cruising in SLIME) to wake it up. Has anyone seen any issues like this before? Or perhaps know if this is even a TBNL issue? I've pasted the output I see from the lisp process (via attachtty) and in my emacs session (after I send an interrupt). Any help would be greatly appreciated, Steve Huffman In attachtty I'll see something like this: Interrupted at #x2811F14E. [Condition of type SIMPLE-CONDITION] Restarts: 0: [CONTINUE] Return from BREAK. 1: [DESTROY ] Destroy the process Debug (type H for help) (UNIX::SIGINT-HANDLER #<unused-arg> #<unused-arg> #.(SYSTEM:INT-SAP #x47FD789C)) Source: Error finding source: Error in function DEBUG::GET-FILE-TOP-LEVEL-FORM: Source file no longer exists: target:code/signal.lisp. 0] and in emacs I'll see something like this: Interrupted at #x2811F14E. [Condition of type SIMPLE-CONDITION] Restarts: 0: [CONTINUE] Return from BREAK. 1: [DESTROY] Destroy the process Backtrace: 0: (UNIX::SIGINT-HANDLER #<#1=unused-arg> #<#1#> #.(SYSTEM:INT-SAP #x47FD789C)) 1: (UNIX::SIGINT-HANDLER 3 #<#1=unused-arg> #<#1#> #.(SYSTEM:INT- SAP #x47FD789C))[:EXTERNAL] 2: ("Foreign function call land") 3: ("Foreign function call land") 4: ("Foreign function call land") 5: ("Foreign function call land") 6: ("Foreign function call land") 7: (LISP::FD-STREAM-READ-N-BYTES #<Stream for descriptor 8> "" 0 14 ...) 8: (LISP::FD-STREAM-READ-N-BYTES 5 #<Stream for descriptor 8> "" 0 ...)[:EXTERNAL] 9: (LISP::READ-INTO-SIMPLE-STRING "" #<Stream for descriptor 8> 0 14) 10: (READ-SEQUENCE "" #<Stream for descriptor 8> :START 0 ...) 11: ((METHOD INITIALIZE-INSTANCE (:AFTER) (TBNL::REQUEST)) (#(1 2 0 3 5 ...) . #()) #<#1=unused-arg> #<TBNL::REQUEST {49094BA5}> #<#1#>) 12: ((MAKE-INSTANCE TBNL::REQUEST :HEADERS-IN PCL::|.P0.|) (("content- stream" . #<Stream for descriptor 8>) ("content-length" . "14") ("content-type" . "application/x-www-form-urlencoded") ("remote-ip- addr" . "172.133.113.57") ("remote-ip-port" . "3332") ...)) 13: (TBNL::PROCESS-REQUEST (("content-stream" . #<Stream for descriptor 8>) ("content-length" . "14") ("content-type" . "application/x-www-form-urlencoded") ("remote-ip-addr" . "172.133.113.57") ("remote-ip-port" . "3332") ...)) 14: (TBNL::LISTEN-FOR-REQUEST #<Stream for descriptor 8> TBNL::PROCESS-REQUEST)

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[tbnl-devel] arbitrary per-request data?
by Zach Beane 17 Sep '05

17 Sep '05

I have an application that has a notion of a current user that is lazily established on a per-request basis. For now, I have been returning a handler that is really a lambda wrapping a real handler that lexically binds the special *current-user*: (defun page-handler (request) (multiple-value-bind (handler foundp) (gethash (script-name request) *handlers*) (when foundp (lambda () (let ((*current-user* *current-user-local-unbound-value*)) (funcall handler)))))) But it occurred to me that there is already the *request* structure. Would it make sense to be able to have a table of arbitrary keys and values in the request structure for application use? I was thinking of an accessor like this: request-data key &optional (request *request*) => value, foundp Then I could write CURRENT-USER something like: (defun current-user () (multiple-value-bind (value foundp) (request-data 'user) (if foundp value (setf (request-data 'user) (cookie-user))))) Right now it's a bit messier than that. What do you think? If this seems reasonable I can work out and submit a patch. Zach

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[tbnl-devel] New macro: create-groups-bind-regex-dispatcher
by Alceste Scalas 01 Sep '05

01 Sep '05

Hello, first of all, congratulations for TBNL :-) Here's a small macro (with a big ugly name) for TBNL, that allows to bind portions of a request URI to arguments passed to dispatch functions. (see attachment) I'm using it to create RESTful [1] URIs and web APIs for a web application I'm playing with. For example, let's say I want to publish a news archive. The "usual" way for accessing the news for August 27th, 2005 would be an URI like: http://www.news.tld/archive?year=2005&month=08&day=27 The proposed add-on allows to easily (well, actually *more* easily) manage URIs like this: http://www.news.tld/archive/2005/08/27/ The task is performed by a macro called create-groups-bind-regex-dispatcher, which takes three arguments: 1. a CL-PPCRE regex (a string, an s-expression or a scanner) with one or more register groups. It will be matched against the request URI; 2. a list of variable names that will be bound to the register groups above iff the regex matches; 3. a dispatch function that accepts keyword arguments named like the variables above. A code sample for the news archive: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - (defun archive-page (&key year month day) "Archive page" (format nil "Year: ~A; Month: ~A; Day: ~A" year month day)) (setq *dispatch-table* (list (create-groups-bind-regex-dispatcher "^\\/archive\\/(\\d{4})\\/(\\d{1,2})\\/(\\d{1,2})\\/?$" (year month day) archive-page) #'default-dispatcher)) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - Under the hood, the list of variables provided to create-groups-bind-regex-dispatcher is used with cl-ppcre:register-groups-bind --- so you can apply some voodoo to the matched variables: - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - (defun archive-page (&key year month day) "Archive page with integer keyword parameters" (format nil "(+ year month day) => ~D" (+ year month day))) (setq *dispatch-table* (list (create-groups-bind-regex-dispatcher "^\\/archive\\/(\\d{4})\\/(\\d{1,2})\\/(\\d{1,2})\\/?$" ((#'parse-integer year month day)) archive-page) #'default-dispatcher)) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - That's all. I hope it will be useful for you as well... Comments are welcome (please don't be too rude, it's one of my first attempts with CL :-) Regards, alceste References: [1] http://www.ics.uci.edu/~fielding/pubs/dissertation/top.htm -- Alceste Scalas <alceste.scalas(a)gmx.net>

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[tbnl-devel] New version 0.5.0 / Multiple back-ends
by Edi Weitz 17 Aug '05

17 Aug '05

Hi! I've finally found some time to incorporate Bob's changes, test them and document them. I've also changed the logging API and re-factored some of the code. I'm sure I broke something in the process so please test... :) Specifically, I tried to explain in the documentation how TBNL talks with the different back-ends. I also changed the test setup so that it now hopefully adapts to all three back-ends and gives new users a chance to understand how TBNL works. While testing the "stand-alone" version I had some problems with MS Internet Explorer but I /think/ I've nailed them down now. Note that some of the changes in 0.5.0 might break API compatibility with earlier versions so be careful if you use this release for an existing deployment of TBNL and resort to the docs if in doubt. Special thanks to Bob Hutchison who made this all possible! Download: <http://weitz.de/files/tbnl.tar.gz>. Have fun, Edi.

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[tbnl-devel] SBCL: Can't cope with too many threads
by Stefan Scholl 14 Aug '05

14 Aug '05

Hi! Just ran a small test with sbcl and standalone TBNL. "-c 50" (ApacheBench, 50 simultaneous requests) was too much for the poor litte server. It just froze. Don't really know who's to blame. But maybe it's possible to limit the requests on the TBNL (KMRCL?) side that are served simultaneously -- according to some magic numbers some SBCL wizards could supply. How do the Araneida guys deal with it? Don't use threads, just serve event? Regards, Stefan

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[tbnl-devel] SCGI support?
by Stefan Scholl 10 Aug '05

10 Aug '05

Hi! Has anyone thought about implementing a SCGI interface for TBNL? That way it could work together with Apache + mod_scgi, or even better: lighttpd + mod_scgi lighttpd: http://www.lighttpd.net/ SCGI specification: http://python.ca/nas/scgi/protocol.txt Regards, Stefan

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[tbnl-devel] Upload of text files
by Jaroslaw.Tomczak＠sanofi-aventis.com 02 Aug '05

02 Aug '05

Hi, I have noticed a minor problem when uploading text files with TBNL (version 0.5.5 + Apache 2.0.54 + mod_lisp2 + LispWorks 4.4.5, all on Windows 2000) -- DOS/Windows text files (CR/LF) have one empty line appended at the end when uploaded. Unix text files, however, are transferred correctly. Any ideas? Jaroslaw Tomczak P.S. Edi, thanks for your great libraries! -- Dr. Jaroslaw Tomczak Aventis Pharma Deutschland GmbH A company of the sanofi-aventis group SMA Chemical Sciences Drug Design I Industriepark Hoechst, H840 room 104 D-65926 Frankfurt / Main phone: +49 (69) 305-14710 fax: +49 (69) 305-13068

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