factor/extra/spider/spider.factor

128 lines
3.8 KiB
Factor

! Copyright (C) 2008 Doug Coleman.
! See http://factorcode.org/license.txt for BSD license.
USING: accessors fry html.parser html.parser.analyzer
http.client kernel tools.time sets assocs sequences
concurrency.combinators io threads namespaces math multiline
math.parser inspector urls logging combinators.short-circuit
continuations calendar prettyprint dlists deques locals
spider.unique-deque combinators concurrency.semaphores ;
IN: spider
TUPLE: spider base count max-count sleep max-depth initial-links
filters spidered todo nonmatching quiet currently-spidering
#threads semaphore follow-robots? robots ;
TUPLE: spider-result url depth headers
fetched-in parsed-html links processed-in fetched-at ;
: <spider> ( base -- spider )
>url
spider new
over >>base
over >>currently-spidering
swap 0 <unique-deque> [ push-url ] keep >>todo
<unique-deque> >>nonmatching
0 >>max-depth
0 >>count
1/0. >>max-count
H{ } clone >>spidered
1 [ >>#threads ] [ <semaphore> >>semaphore ] bi ;
: <spider-result> ( url depth -- spider-result )
spider-result new
swap >>depth
swap >>url ;
<PRIVATE
: apply-filters ( links spider -- links' )
filters>> [ '[ [ _ 1&& ] filter ] call( seq -- seq' ) ] when* ;
: push-links ( links level unique-deque -- )
'[ _ _ push-url ] each ;
: add-todo ( links level spider -- )
todo>> push-links ;
: add-nonmatching ( links level spider -- )
nonmatching>> push-links ;
: filter-base-links ( spider spider-result -- base-links nonmatching-links )
[ base>> host>> ] [ links>> prune ] bi*
[ host>> = ] with partition ;
: add-spidered ( spider spider-result -- )
[ [ 1+ ] change-count ] dip
2dup [ spidered>> ] [ dup url>> ] bi* rot set-at
[ filter-base-links ] 2keep
depth>> 1+ swap
[ add-nonmatching ]
[ tuck [ apply-filters ] 2dip add-todo ] 2bi ;
: normalize-hrefs ( base links -- links' )
[ derive-url ] with map ;
: print-spidering ( spider-result -- )
[ url>> ] [ depth>> ] bi
"depth: " write number>string write
", spidering: " write . yield ;
:: fill-spidered-result ( spider spider-result -- )
f spider-result url>> spider spidered>> set-at
[ spider-result url>> http-get ] benchmark :> fetched-in :> html :> headers
[
html parse-html
spider currently-spidering>>
over find-all-links normalize-hrefs
] benchmark :> processed-in :> links :> parsed-html
spider-result
headers >>headers
fetched-in >>fetched-in
parsed-html >>parsed-html
links >>links
processed-in >>processed-in
now >>fetched-at drop ;
:: spider-page ( spider spider-result -- )
spider quiet>> [ spider-result print-spidering ] unless
spider spider-result fill-spidered-result
spider quiet>> [ spider-result describe ] unless
spider spider-result add-spidered ;
\ spider-page ERROR add-error-logging
: spider-sleep ( spider -- ) sleep>> [ sleep ] when* ;
: queue-initial-links ( spider -- )
[
[ currently-spidering>> ] [ initial-links>> ] bi normalize-hrefs 0
] keep add-todo ;
: spider-page? ( spider -- ? )
{
[ todo>> deque>> deque-empty? not ]
[ [ todo>> peek-url depth>> ] [ max-depth>> ] bi < ]
[ [ count>> ] [ max-count>> ] bi < ]
} 1&& ;
: setup-next-url ( spider -- spider spider-result )
dup todo>> peek-url url>> >>currently-spidering
dup todo>> pop-url [ url>> ] [ depth>> ] bi <spider-result> ;
: spider-next-page ( spider -- )
setup-next-url spider-page ;
PRIVATE>
: run-spider-loop ( spider -- )
dup spider-page? [
[ spider-next-page ] [ spider-sleep ] [ run-spider-loop ] tri
] [
drop
] if ;
: run-spider ( spider -- spider )
"spider" [
dup queue-initial-links [ run-spider-loop ] keep
] with-logging ;