1 files changed, 44 insertions, 0 deletions
diff --git a/lualib/redis_scripts/bayes_learn.lua b/lualib/redis_scripts/bayes_learn.lua
new file mode 100644
index 0000000..80d86d8
--- /dev/null
+++ b/lualib/redis_scripts/bayes_learn.lua
@@ -0,0 +1,44 @@
+-- Lua script to perform bayes learning
+-- This script accepts the following parameters:
+-- key1 - prefix for bayes tokens (e.g. for per-user classification)
+-- key2 - boolean is_spam
+-- key3 - string symbol
+-- key4 - boolean is_unlearn
+-- key5 - set of tokens encoded in messagepack array of strings
+-- key6 - set of text tokens (if any) encoded in messagepack array of strings (size must be twice of `KEYS[5]`)
+
+local prefix = KEYS[1]
+local is_spam = KEYS[2] == 'true' and true or false
+local symbol = KEYS[3]
+local is_unlearn = KEYS[4] == 'true' and true or false
+local input_tokens = cmsgpack.unpack(KEYS[5])
+local text_tokens
+
+if KEYS[6] then
+  text_tokens = cmsgpack.unpack(KEYS[6])
+end
+
+local hash_key = is_spam and 'S' or 'H'
+local learned_key = is_spam and 'learns_spam' or 'learns_ham'
+
+redis.call('SADD', symbol .. '_keys', prefix)
+redis.call('HSET', prefix, 'version', '2') -- new schema
+redis.call('HINCRBY', prefix, learned_key, is_unlearn and -1 or 1) -- increase or decrease learned count
+
+for i, token in ipairs(input_tokens) do
+  redis.call('HINCRBY', token, hash_key, 1)
+  if text_tokens then
+    local tok1 = text_tokens[i * 2 - 1]
+    local tok2 = text_tokens[i * 2]
+
+    if tok1 then
+      if tok2 then
+        redis.call('HSET', token, 'tokens', string.format('%s:%s', tok1, tok2))
+      else
+        redis.call('HSET', token, 'tokens', tok1)
+      end
+
+      redis.call('ZINCRBY', prefix .. '_z', is_unlearn and -1 or 1, token)
+    end
+  end
+end
+\ No newline at end of file