# HG changeset patch
# User Matthew Wild <mwild1@gmail.com>
# Date 1536852948 -3600
# Node ID feaef6215bb845c79963b0b3d0f9da6f6b3fabbb
# Parent  35c128b42509dac298f6554baee1a9571dc1d9df
util.stanza: Don't automatically generate ids for iq stanzas

Users of this API should provide their own id attribute that meets their
uniqueness requirements.

The current implementation leaks information (i.e. how many iq stanzas
have been sent by the server to other JIDs). Providing any strong
guarantees of randomness here would need to pull in additional
dependencies that we don't want in this simple library.

diff -r 35c128b42509 -r feaef6215bb8 spec/util_stanza_spec.lua
--- a/spec/util_stanza_spec.lua	Thu Sep 13 17:28:50 2018 +0200
+++ b/spec/util_stanza_spec.lua	Thu Sep 13 16:35:48 2018 +0100
@@ -84,9 +84,20 @@
 	end);
 
 	describe("#iq()", function()
-		it("should work", function()
-			local i = st.iq();
-			assert.are.equal(i.name, "iq");
+		it("should create an iq stanza", function()
+			local i = st.iq({ id = "foo" });
+			assert.are.equal("iq", i.name);
+			assert.are.equal("foo", i.attr.id);
+		end);
+
+		it("should reject stanzas with no id", function ()
+			assert.has.error_match(function ()
+				local i = st.iq();
+			end, "id attribute");
+
+			assert.has.error_match(function ()
+				local i = st.iq({ foo = "bar" });
+			end, "id attribute");
 		end);
 	end);
 
diff -r 35c128b42509 -r feaef6215bb8 util/stanza.lua
--- a/util/stanza.lua	Thu Sep 13 17:28:50 2018 +0200
+++ b/util/stanza.lua	Thu Sep 13 16:35:48 2018 +0100
@@ -347,12 +347,6 @@
 	return error_type, condition or "undefined-condition", text;
 end
 
-local id = 0;
-local function new_id()
-	id = id + 1;
-	return "lx"..id;
-end
-
 local function preserialize(stanza)
 	local s = { name = stanza.name, attr = stanza.attr };
 	for _, child in ipairs(stanza) do
@@ -430,8 +424,10 @@
 	end
 end
 local function iq(attr)
-	if attr and not attr.id then attr.id = new_id(); end
-	return new_stanza("iq", attr or { id = new_id() });
+	if not (attr and attr.id) then
+		error("iq stanzas require an id attribute");
+	end
+	return new_stanza("iq", attr);
 end
 
 local function reply(orig)
@@ -502,7 +498,6 @@
 	stanza_mt = stanza_mt;
 	stanza = new_stanza;
 	is_stanza = is_stanza;
-	new_id = new_id;
 	preserialize = preserialize;
 	deserialize = deserialize;
 	clone = clone;