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GetAllHTML v1.00 Copyright 1998-2002 Christoper S Handley
==========================================================
Latest News
-----------
This is (probably) my final release, as I have not updated the code in two
years, and it seems to work very well for me. Since it works well, I have
finally given it v1.00 status!
Should now work on even more HTML pages due to minor improvements.
If you cannot get ARexx to work, please read my warning below about text
editors.
Introduction
------------
Have you ever visited a cool web site & wanted to keep a copy of some/all of it,
but it would takes ages to find & download all the respective pages/files?
This is the answer!
You supply this ARexx script with the start page URL, and a destination
directory (which should be empty), and maybe a few other options - and off it
goes! Note that it needs HTTPResume v1.3+ to work (get from Aminet).
The idea for this came from a PC Java program called PageSucker - sadly it is
over 1Mb in size & buggy (& can't be run on the Amiga, yet). Although my
implementation may not have quite as many features, it is does do the job quite
fast, & has relatively low memory overheads.
Requirements
------------
o HTTPResume v1.3+ (but v1.7 is recommended)
o An Amiga capable of running ARexx programs
o Libs:Rexxsupport.library
o Modem with TCP/IP stack (like Genesis, Miami, or AmiTCP)
Usage
-----
1.Before running it for the first time you must (text) edit (say using C:ED) it
to know where your copy of HTTPResume is located. Go to line 19 where it says:
HTTPResume='Programs:Utils/Comms/HTTPResume'
Alter the file path between the 'quotes' to where you keep HTTPResume, and save.
2.Run your TCP/IP stack (e.g.AmiTCP/Genesis or Miami).
3.Run it from a Shell using:
Sys:RexxC/Rx GetAllHTML arguments
Where the arguments are:
"URL"/A, "DestDir"/A, NOASK/S, ARC/S, PIC/S, RESUME/S, PAUSE/S, DEPTH=/N/K,
NOBASEINDEX, PORT=/K, BASEURL=/K, BROKELINKS/S
Note - The destination dir must be empty of any previous attempt at downloading
that web page (unless using the RESUME switch). And that both URL & DestDir
*must* be enclosed in "double quotes" - and that the BASEURL must NOT be
surrounded by quotes!
*Note* you may have several GetAllHTMLs & HTTPResumes running at the same time
(not on the same URL!), and that if you use the PORT argument then you will need
HTTPResume running first.
See the file GetAllHTML_ex.script for an example usage - it will download all of
Squid's on-line artwork (hope he gets a few more sales of his wonderful 'other
world' artwork from this :-).
Behaviour
---------
It's default behaviour is to find all links in each HTML page, and download them
if:
-the URL path is a sub-directory of the original URL path; this stops
downloading irrelevant pages on different topics, different servers, etc.., AND
-if they are HTML pages (name ends in .html, etc), OR
-if not HTML pages then it will ask if the file should be downloaded; if answer
does not begin with an "n" then it does (download). If the file has the same
suffix as the last positively confirmed download, then 'intelligently' assumes
should download...
This behaviour is modified by various switches:
RESUME - Should downloading of pages have been interupted (maybe a crash), run
GetAllHTML with *exactly* the same options, except with this switch too.
It will take a while to reach the same place as all previous HTML pages
must be scanned - and some additional memory usage is incured.
I suggest you don't go on-line until it has reached the previously
interupted point (it wait for you to press return).
*NOTE* that this mode is flawed due to the way GetAllHTML.rexx works,
so that it will sometimes think it has reached the previously finished
point, when it has not in fact. Still RESUME is very useful! And an
AmigaE version would fix this.
PIC - Will identify links to pictures & download them rather than ask.
ARC - Will identify links to archives & download them rather than ask.
NOASK - Do not ask user if should download a file, assume should not.
PAUSE - DO ask user to "press <return>" if we get an empty URL or couldn't
download a file. Always asked to by the RESUME function.
TERSE - Only outputs very important text, so it won't report strange URLs,
failure to download files, non-http links, etc...
PORT - Supplies the ARexx port of a *running* HTTPResume; if supplied then
does not try to launch HTTPResume from AmigaDOS. See *Note* below. If
no port name is supplied then it sees if the current ARexx port is
already set to some HTTPResume - if not then an error is generated, else
it just uses that port.
DEPTH - This allows you to specify how many URL links to follow in sequence;
i.e.the depth of the search. DEPTH=2 means download only the links from
the original page, and so on for DEPTH=3, etc.. See *Note* below. If
no number is supplied then the user is asked for a number.
NOBASEINDEX - This prevents GetAllHTML from following links to the index of the
original URL path. Is useful for web sites which are fairly 'flat'
(ie.do not have many sub-directories), which also have banners at the
top of pages to take you straight to the site's main page (which will
has links you are not interested in). Probably very rarely needed.
BASEURL - This allows you to override the semi-intelligent default, and tell
GetAllHTML the base URL - that is, what the URL must start with for it
to even consider downloading it. This is useful if you wish to download
from a particular page deep down the directory structure, but which
references images (or maybe pages) that are further up.
BROKENLINKS - This causes attempted downloading of pages that are not
sub-directories of the original URL. These will be downloaded to "T:"
(which is usually "RAM:T") & then deleted. If download failed then you
will be told that there was a broken link. See suggested uses below.
*Note* that both DEPTH & PORT must be followed by an equals sign ("=") and then
the data, _without_ any spaces between anything. This is due to a limitation of
ARexx, for which an AmigaE version would fix.
SOLUTIONS TO FREQUENT PROBLEMS
------------------------------
1.If ARexx complains there is an error in the GetAllHTML code (when you try to
run it), then it is VERY likely that the problem comes from editing GetAllHTML
in a text editor.
Many text editors seem to be EXTREMELY badly coded, so that they can't handle
the very long lines I have in GetAllHTML; they usually end up splitting a line
in 2, or even deleting everything past a certain point on the line...
I strongly suggest buying CygnusEd (v3.5 or v4), as this is what I use, and I
have never had any problems with it; it can even load in binary files, and save
them back without loosing anything!
Suggested uses
--------------
1.There's a big web site with lots of pictures/music/archives/information that
interests you. Depending on what you want, you will need to use the PIC, ARC,
and NOASK switches.
For instance, if you are only interested in pictures then use PIC & NOASK. If
you are only interested in archives then use ARC & NOASK. If you are interested
in something else than pictures or archives (in addition to the web pages), then
don't use any of those three switches - GetAllHTML will ask you if something
should be downloaded.
2.You have your own home-page on the web, and it includes lots of links to other
sites for which take hours to check they are all valid. Point GetAllHTML at
your web site with the BROKENLINKS switch. Note it will never try to download a
link twice, even withOUT using RESUME.
In fact, if you have your web site in a directory on your HD, then you could
RESUME with that directory as your download directory; this will be MUCH faster
since none of your pages will (or should) be downloaded :-)) . First time you
try this, do it on a back-up copy to ensure GetAllHTML does not do anything
strange (I won't be held responsible for extra files 'magically' appearing!)..
3.I haven't tried this out myself, but it should be really cool:
If you have a favourite news page then you can use GetAllHTML to download just
the latest news. Suggest use NOASK, possibly with PIC if you want pictures too.
You will obviously need to delete (or rename) the main news-page file, to force
GetAllHTML to download the latest index which contains links to the new news.
I don't think you need to use RESUME, but...
Any other ideas?
Bugs & other unwelcome features
-------------------------------
o The RESUME feature *may* cause some files to be missed, but this depends on
how ARexx treats funny characters for variable names. An AmigaE version would
fix any problems.
o Interpretation of the HTML & URLs is based on observation rather than any
specification of these standards - thus there will probably be rare cases in
which it may misinterpret them; as long as these are reported (along with the
responsible HTML file(s)), fixes will probably be forth coming.
But it really seems to work fine for the sites I have tried :-)
o You cannot go above a depth of 42; this is to protect against an ARexx
limitation which will cause problems above a depth of about 45. An AmigaE
version would fix this.
Technical info
--------------
GetAllHTML uses a depth-first tree search, via recursion, and uses the existance of
(downloaded) files as a super-fast (for ARexx!) record of whether a page has
been visited or not.
When RESUMEing, existance of files cannot be used to record if a page has been
visited, so an alternate method is used - this is slower, and could fail with
certain combinations of strangely named URLs (very unlikely); a far slower
method would avoid this, but was considered unnecessary.
I used the INTERPRET command to do some magic with ARexx to make the arbitarily
long linked-lists (really branches) possible - they were required for storing
what pages have been visited. Although this method is not very memory efficient
(many duplicate entries of the same URL), it is quite fast - and more
importantly it *works* in ARexx. I had thought it would be virtually impossible
to make arbitarily extended link-lists in ARexx, but the interpretive nature of
ARexx means you can effectively create ARexx commands on-the-fly.
Future
------
I have no plans for the future. It has proven to work very well, and I have not
updated it in 2 years.
About the Author
----------------
My name is Christopher S Handley. You're not really interested in me are you?!
Contacting the Author
---------------------
Email: cshandley@iee.org
I am not yet sure about giving my snail mail address to all & sundry - sorry
about that :-(I know how I felt when people did that before I had email access).
Thanks to
---------
o Andrija Antonijevic for HTTPResume
o the Amiga community for sticking with the Amiga, and continuing to innovate.
Give your backing to KOSH (originally proposed by Fleecy Moss).
o CU Amiga for becoming the greatest Amiga mag over the last year, before
passing away. I did not like AF's Xmas issue at all (and AF didn't appear to
like my criticism of it either...)
o whoever design the Rexx language - Rexx is great for 'user utilities'.
History
-------
v1.00 (22-08-02) - Should now handle URLs with "?" in them. Now considers
SWF (flash) files as pictures. Final version?
Added anti-spam stuff to email address :(
v0.66ß (30-01-00) - Updated docs with new email address, warning about text
editors causing problems, and other small changes.
v0.65ß (16-10-99) - Now searches from "HREF=" not "<A HREF=" which will give
dramatic improvement on some pages! Rewrote how "./"s are
interpreted, which seems to be much better (perfect?).
Added the NOBASEINDEX switch. Removed uses of Translate()
since it was doing nothing - so a small speed-up (esp.for
RESUME).
v0.64ß (04-04-99) - Put back the 'extra' END that I removed in v0.61 . Now
BROKENLINKS will always only try to download external links
once. Removed NOENV argument of HTTPResume so proxy
settings may work. Minor changes.
v0.63ß (04-04-99) - Removed spurious non-visible ASCII (27) characters that
caused some text editors to go loopy.
v0.62ß (03-04-99) - Add the BROKENLINKS switch. Replaced NOPAUSE by PAUSE
switch. Now always warns if a file could not be downloaded
(not just pages). If you used all the arguments then it
would miss the last one.
v0.61ß (28-03-99) - Possible fix for RESUME problem done, plus stupidly left an
extra END where it broke GetAllHTML.
v0.60ß (27-03-99) - First stand-alone Aminet release. Damn! There were 3 big
mistakes... (a)some files expected as directories,
(b)local-path expansion was too complex & probably wrong
(hope right now), (c)implicit InDeX.hTmL files were not
scanned for files. Also asked user to press return but
really wanted a key first!
v0.55ß (14-12-98) - Damn! All this fast programming has introduced some bugs,
but they are fixed now; included the "~" interpretation was
completely wrong (removed), and fixed a long standing bug
where a URL beginning with a slash was mis-understood. Also
added the BASEURL feature which is really useful sometimes.
v0.54ß (12-12-98) - Given I couldn't download the KOSH pages (www.kosh.net), I
added basic frame support, and fixed a long standing bug
where root html pages could appear as empty directories!
Two more long standing bugs fixed (ARC & PIC switches had
inverted sense). Add fix for paths with "~" in, so will
align path correctly. Add semi-intelligence so that won't
ask about downloading a file with the same suffix as the
last file that was confirmed. Add the TERSE function.
v0.53ß (10-12-98) - The DEPTH feature now works, added the PORT feature,
added the NOPAUSE feature. Fixed long standing bug of NOASK
not being recognised. Now removes text in URL after "?"s.
v0.52ß ( 8-12-98) - Basically update documentation ready for it's first Aminet
release, for when packaged along with HTTPResume. Added an
untested DEPTH feature in the special v0.52aß.
v0.51ß (??-??-98) - Internal speed-up (may be much faster downloading small pages)
- minor fix of arguments given to HTTPResume
v0.5ß (??-??-98) - Initial release to a few people. No bugs, honest =:)