* Add meta-classification example.

Many changes to advanced statistic and meta-classification logic.
Add example of complex meta-classification.

1 files changed, 100 insertions, 14 deletions

diff --git a/conf/lua/rspamd.classifiers.lua b/conf/lua/rspamd.classifiers.lua
index e158a29a6..de1e23506 100644
--- a/conf/lua/rspamd.classifiers.lua
+++ b/conf/lua/rspamd.classifiers.lua
@@ -1,5 +1,76 @@
 -- Detect language of message and selects appropriate statfiles for it
 
+-- Common labels for specific statfiles
+local many_recipients_label = 'many recipients'
+local undisclosed_recipients_label = 'undisclosed recipients'
+local list_label = 'maillist'
+local long_subject_label = 'long subject'
+local different_reply_to_label = 'different reply to'
+local has_in_reply_label = 'reply message'
+
+-- Get specific statfiles set based on message rules
+local function get_specific_statfiles(classifier, task)
+	local spec_st = {}
+	-- More 5 recipients
+	local st_many = classifier:get_statfile_by_label(many_recipients_label)
+	if st_many then
+		rcpt = task:get_recipients()
+		if rcpt and table.maxn(rcpt) > 5 then
+			print(table.maxn(rcpt))
+			table.foreach(st_many, function(i,v) table.insert(spec_st,v) end)
+		end
+	end
+	-- Undisclosed
+	local st_undisc = classifier:get_statfile_by_label(undisclosed_recipients_label)
+	if st_undisc then
+		rcpt = task:get_recipients()
+		if rcpt and table.maxn(rcpt) == 0 then
+			table.foreach(st_undisc, function(i,v) table.insert(spec_st,v) end)
+		end
+	end
+	-- Maillist
+	local st_maillist = classifier:get_statfile_by_label(list_label)
+	if st_maillist then
+		local unsub_header = task:get_raw_header('List-Unsubscribe')
+		if unsub_header and unsub_header[1] then
+			table.foreach(st_maillist, function(i,v) table.insert(spec_st,v) end)
+		end
+	end
+	-- Long subject
+	local st_longsubj = classifier:get_statfile_by_label(long_subject_label)
+	if st_longsubj then
+		local subj = task:get_raw_header('Subject')
+		if subj and subj[1] and string.len(subj[1]['value']) > 150 then
+			table.foreach(st_longsubj, function(i,v) table.insert(spec_st,v) end)
+		end
+	end
+	-- Reply-To != To
+	local st_replyto = classifier:get_statfile_by_label(different_reply_to_label)
+	if st_replyto then
+		local to = task:get_raw_header('To')
+		local reply_to = task:get_raw_header('Reply-To')
+		if to and to[1] and reply_to and reply_to[1] then
+			if string.lower(to[1]['value']) ~= string.lower(reply_to[1]['value']) then
+				table.foreach(st_replyto, function(i,v) table.insert(spec_st,v) end)
+			end
+		end
+	end
+	-- Has In-Reply-To header
+	local st_reply = classifier:get_statfile_by_label(has_in_reply_label)
+	if st_reply then
+		local inrep_header = task:get_raw_header('In-Reply-To')
+		if inrep_header and inrep_header[1] then
+			table.foreach(st_reply, function(i,v) table.insert(spec_st,v) end)
+		end
+	end
+	
+	if table.maxn(spec_st) > 1 then
+		return spec_st
+	else
+		return nil
+	end
+end
+
 classifiers['bayes'] = function(classifier, task, is_learn, is_spam)
 	-- Subfunction for detection of message's language
 	local detect_language = function(task)
@@ -14,35 +85,50 @@ classifiers['bayes'] = function(classifier, task, is_learn, is_spam)
 	end
 
 	-- Main procedure
+	local selected = {}
+	local spec_st = get_specific_statfiles(classifier, task)
+	if spec_st then
+		if is_learn then
+			return spec_st
+		else
+			-- Merge tables
+			table.foreach(spec_st, function(i,v) table.insert(selected,v) end)
+		end
+	end
+	-- Detect statfile by language
 	language = detect_language(task)
 	if language then
 		-- Find statfiles with specified language
-		local selected = {}
-		for _,st in pairs(classifier:get_statfiles()) do
-			local st_l = st:get_param('language')
-			if st_l and st_l == language then
-			    -- Insert statfile with specified language    
-			    table.insert(selected, st)
+		for _,st in ipairs(classifier:get_statfiles()) do
+			-- Skip labeled statfiles
+			if not st:get_label() then
+				local st_l = st:get_param('language')
+				if st_l and st_l == language then
+					-- Insert statfile with specified language    
+					table.insert(selected, st)
+				end
 			end
 		end
 		if table.maxn(selected) > 1 then
 			return selected
 		end
-	else
-		-- Language not detected
-		local selected = {}
-		for _,st in ipairs(classifier:get_statfiles()) do
+	end
+
+	-- Language not detected or specific language statfiles have not been found
+	for _,st in ipairs(classifier:get_statfiles()) do
+		-- Skip labeled statfiles
+		if not st:get_label() then
 			local st_l = st:get_param('language')
 			-- Insert only statfiles without language
 			if not st_l then
 				table.insert(selected, st)
 			end
 		end
-		if table.maxn(selected) > 1 then
-			return selected
-		end
 	end
-
+	if table.maxn(selected) > 1 then
+		return selected
+	end
+	
 	return nil
 end