write a bit of tests for a lua script that calls into chatctl.py (#1)

* add a lua test script running directly against  chatctl.py

src/chatmail/chatctl/test.lua

@@ -0,0 +1,73 @@
+
+-- To run this test: run "lua test.lua" while in the same directory as chatctl.py
+
+if dovecot == nil then
+    dovecot = {
+        auth = {
+            PASSDB_RESULT_OK="OK",
+            PASSDB_RESULT_PASSWORD_MISMATCH="MISMATCH"
+        }
+    }
+end
+
+-- Escape shell argument by hex encoding it and wrapping in quotes.
+function escape(data)
+   b16 = data:gsub(".", function(char) return string.format("%2X", char:byte()) end)
+   return ("'"..b16.."'")
+end
+
+-- call out to python program to actually manage authentication for dovecot
+
+function chatctl_verify(user, password)
+    return os.execute("python chatctl.py hexauth "..escape(user).." "..escape(password))
+end
+
+function chatctl_lookup(hex, user) 
+    return os.execute("python chatctl.py hexlookup "..escape(user))
+end
+
+
+function auth_password_verify(request, password)
+    if chatctl_verify(request.user, password) then
+        return dovecot.auth.PASSDB_RESULT_OK, {}
+    end
+    return dovecot.auth.PASSDB_RESULT_PASSWORD_MISMATCH, ""
+end
+
+function auth_passdb_lookup(request)
+    if chatctl_lookup(request.user) then
+        return dovecot.auth.PASSDB_RESULT_OK, {}
+    end
+    return dovecot.auth.PASSDB_RESULT_USER_UNKNOWN, "no such user"
+end
+
+function auth_userdb_lookup(request)
+    if chatctl_lookup(request.user) then
+        return dovecot.auth.USERDB_RESULT_OK, "uid=vmail gid=vmail"
+    end
+    return dovecot.auth.USERDB_RESULT_USER_UNKNOWN, "no such user"
+end
+
+function split_chatctl_results(output) 
+    local ret = {}
+    for key, value in output:gmatch "(%w+)%s*=%s*(%w+)" do
+        ret[key] = value
+    end
+    return ret
+end
+
+function test_ok(user, password) 
+    local res = auth_password_verify({user=user}, password)
+    assert(res=="OK")
+    print("OK test_ok "..user.." "..password)
+end
+
+function test_mismatch(user, password) 
+    local res = auth_password_verify({user=user}, password)
+    assert(res == "MISMATCH")
+    print("OK test_mismatch "..user.." "..password)
+end
+
+test_ok("link2xt@instant2.testrun.org", "Ahyei6ie")
+test_mismatch("link2xt@instant2.testrun.org", "Aqwlek")
+