<HTML>
<HEAD>
<META NAME="GENERATOR" CONTENT="SGML-Tools 1.0.9">
- <TITLE>The DXSpider Installation and Administration Manual : The Client program</TITLE>
+ <TITLE>The DXSpider Administration Manual v1.47: Filtering (Old Style upto v1.44)</TITLE>
<LINK HREF="adminmanual-3.html" REL=next>
<LINK HREF="adminmanual-1.html" REL=previous>
<LINK HREF="adminmanual.html#toc2" REL=contents>
+<link rel=stylesheet href="style.css" type="text/css" title="default stylesheet">
</HEAD>
<BODY>
<A HREF="adminmanual-3.html">Next</A>
<A HREF="adminmanual-1.html">Previous</A>
<A HREF="adminmanual.html#toc2">Contents</A>
<HR>
-<H2><A NAME="s2">2. The Client program</A></H2>
-
-<P>In earlier versions of Spider, all the processes were Perl scripts. This
-was fine but with a lot of users your computer memory would soon be used up.
-To combat this a new client was written in "C". This client only works for
-<EM>incoming</EM> connects at the moment. Before you can use it though it
-has to be "made". CD to /spider/src and type <EM>make</EM>. You
-should see the output on your screen and hopefully now have a small C program
-called <EM>client</EM>. Leave it in this directory.
+<H2><A NAME="s2">2. Filtering (Old Style upto v1.44)</A></H2>
+
+<P>Filters can be set for spots, announcements and WWV. You will find the
+directories for these under /spider/filter. You will find some examples in
+the directories with the suffix <EM>.issue</EM>. There are two types of
+filter, one for incoming information and one for outgoing information.
+Outgoing filters are in the form <EM>CALLSIGN.pl</EM> and incoming filters
+are in the form <EM>in_CALLSIGN.pl</EM>. Filters can be set for both nodes
+and users.
+<P>
+<P>All filters work in basically the same way. There are several elements
+delimited by commas. There can be many lines in the filter and they are
+read from the top by the program. When writing a filter you need to think
+carefully about just what you want to achieve. You are either going to write
+a filter to <EM>accept</EM> or to <EM>reject</EM>. Think of a filter as
+having 2 main elements. For a reject filter, you would have a line or multiple
+lines rejecting the things you do not wish to receive and then a default line
+accepting everything else that is not included in the filter. Likewise, for an
+accept filter, you would have a line or multiple lines accepting the things you
+wish to receive and a default line rejecting everthing else.
+<P>
+<P>In the example below, a user requires a filter that would only return SSB spots
+posted in Europe on the HF bands. This is achieved by first rejecting the CW
+section of each HF band and rejecting all of VHF, UHF etc based on frequency.
+Secondly, a filter rule is set based on CQ zones to only accept spots posted in
+Europe. Lastly, a default filter rule is set to reject anything outside the filter.
+<P>
+<BLOCKQUOTE><CODE>
+<PRE>
+$in = [
+ [ 0, 0, 'r', # reject all CW spots
+ [
+ 1800.0, 1850.0,
+ 3500.0, 3600.0,
+ 7000.0, 7040.0,
+ 14000.0, 14100.0,
+ 18068.0, 18110.0,
+ 21000.0, 21150.0,
+ 24890.0, 24930.0,
+ 28000.0, 28180.0,
+ 30000.0, 49000000000.0,
+ ] ,1 ],
+ [ 1, 11, 'n', [ 14, 15, 16, 20, 33, ], 15 ], #accept EU
+ [ 0, 0, 'd', 0, 1 ], # 1 = want, 'd' = everything else
+];
+</PRE>
+</CODE></BLOCKQUOTE>
+<P>
+<P>The actual elements of each filter are described more fully in the following
+sections.
+<P>
+<H2><A NAME="ss2.1">2.1 Spots</A>
+</H2>
+
+<P>The elements of the Spot filter are ....
+<P>
+<BLOCKQUOTE><CODE>
+<PRE>
+[action, field_no, sort, possible_values, hops]
+</PRE>
+</CODE></BLOCKQUOTE>
+<P>
+<P>There are 3 elements here to look at. Firstly, the action element. This is
+very simple and only 2 possible states exist, accept (1) or drop (0).
+<P>
+<P>The second element is the field_no. There are 13 possiblities to choose from
+here ....
+<P>
+<BLOCKQUOTE><CODE>
+<PRE>
+ 0 = frequency
+ 1 = call
+ 2 = date in unix format
+ 3 = comment
+ 4 = spotter
+ 5 = spotted dxcc country
+ 6 = spotter's dxcc country
+ 7 = origin
+ 8 = spotted itu
+ 9 = spotted cq
+ 10 = spotter's itu
+ 11 = spotter's cq
+ 12 = callsign of the channel on which the spot has appeared
+</PRE>
+</CODE></BLOCKQUOTE>
+<P>
+<P>The third element tells us what to expect in the fourth element. There are
+4 possibilities ....
+<P>
+<BLOCKQUOTE><CODE>
+<PRE>
+ n - numeric list of numbers e.g. [ 1,2,3 ]
+ r - ranges of pairs of numbers e.g. between 2 and 4 or 10 to 17 - [ 2,4, 10,17 ]
+ a - an alphanumeric regex
+ d - the default rule
+</PRE>
+</CODE></BLOCKQUOTE>
+<P>
+<P>The fifth element is simply the hops to set in this filter. This would only
+be used if the filter was for a node of course and overrides the hop count in
+hop_table.pl.
+<P>
+<P>So, let's look at an example spot filter. It does not matter in the example
+who the filter is to be used for. So, what do we need in the filter? We need
+to filter the spots the user/node requires and also set a default rule for
+anything else outside the filter. Below is a simple filter that stops spots
+arriving from outside Europe.
+<P>
+<BLOCKQUOTE><CODE>
+<PRE>
+$in = [
+ [ 0, 4, 'a', '^(K|N|A|W|VE|VA|J)'], # 0 = drop, 'a' = alphanumeric
+ [ 1, 0, 'd', 0, 1 ], # 1 = want, 'd' = everything else
+ ];
+</PRE>
+</CODE></BLOCKQUOTE>
+<P>
+<P>So the filter is wrapped in between a pair of square brackets. This tells
+Spider to look in between these limits. Then each line is contained within
+its own square brackets and ends with a comma. Lets look carefully at the first
+line. The first element is 0 (drop). Therefore anything we put on this line
+will not be accepted. The next element is 4. This means we are filtering by
+the spotter. The third element is the letter "a" which tells the program to
+expect an alphanumeric expression in the fourth element. The fourth element
+is a list of letters separated by the pipe symbol.
+<P>
+<P>What this line does is tell the program to drop any spots posted by anyone in
+the USA, Canada or Japan.
+<P>
+<P>The second line is the default rule for anything else. The "d" tells us this
+and the line simply reads... accept anything else.
+<P>
+<P>You can add as many lines as you need to complete the filter but if there are
+several lines of the same type it is neater to enclose them all as one line.
+An example of this is where specific bands are set. We could write this like
+this ....
+<P>
+<BLOCKQUOTE><CODE>
+<PRE>
+[ 0,0,'r',[1800.0, 2000.0], 1],
+[ 0,0,'r',[10100.0, 10150.0], 1],
+[ 0,0,'r',[14000.0, 14350.0], 1],
+[ 0,0,'r',[18000.0, 18200.0], 1],
+</PRE>
+</CODE></BLOCKQUOTE>
+<P>
+<P>But the line below achieves the same thing and is more efficient ....
+<P>
+<BLOCKQUOTE><CODE>
+<PRE>
+ [ 0, 0, 'r',
+ [
+ 1800.0, 2000.0, # top band
+ 10100.0, 10150.0, # WARC
+ 14000.0, 14350.0, # 20m
+ 18000.0, 18200.0, # WARC
+ [ ,1 ],
+</PRE>
+</CODE></BLOCKQUOTE>
+<P>
+<P>
+<H2><A NAME="ss2.2">2.2 Announcements</A>
+</H2>
+
+<P>
+<BLOCKQUOTE><CODE>
+<PRE>
+
+# This is an example announce or filter allowing only West EU announces
+#
+# The element list is:-
+# 0 - callsign of announcer
+# 1 - destination * = all, <callsign> = routed to the node
+# 2 - text
+# 3 - * - sysop, <some text> - special list eg 6MUK, ' ', normal announce
+# 4 - origin
+# 5 - 0 - announce, 1 - wx
+# 6 - channel callsign (the interface from which this spot came)
+
+$in = [
+ [ 1, 0, 'a', '^(P[ABCDE]|DK0WCY|G|M|2|EI|F|ON)' ],
+ [ 0, 0, 'd', 0 ]
+];
+</PRE>
+</CODE></BLOCKQUOTE>
+<P>In this example, only the prefixes listed will be allowed. It is possible to
+be quite specific. The Dutch prefix "P" is followed by several secondary
+identifiers which are allowed. So, in the example, "PA" or "PE" would be ok
+but not "PG". It is even possible to allow information from a single callsign.
+In the example this is DK0WCY, to allow the posting of his Aurora Beacon.
+<P>
+<H2><A NAME="ss2.3">2.3 WWV</A>
+</H2>
+
+<P>
+<BLOCKQUOTE><CODE>
+<PRE>
+
+# This is an example WWV filter
+#
+# The element list is:-
+# 0 - nominal unix date of spot (ie the day + hour:13)
+# 1 - the hour
+# 2 - SFI
+# 3 - K
+# 4 - I
+# 5 - text
+# 6 - spotter
+# 7 - origin
+# 8 - incoming interface callsign
+
+# this one doesn't filter, it just sets the hop count to 6 and is
+# used mainly just to override any isolation from WWV coming from
+# the internet.
+
+$in = [
+ [ 1, 0, 'd', 0, 6 ]
+];
+</PRE>
+</CODE></BLOCKQUOTE>
+<P>
+<P>It should be noted that the filter will start to be used only once a user/node
+has logged out and back in again.
+<P>I am not going to spend any more time on these filters now as they will become
+more "comprehensive" in the near future.
<P>
<HR>
<A HREF="adminmanual-3.html">Next</A>