Mention why we don't use xml2

1 files changed, 4 insertions, 0 deletions

diff --git a/README.rst b/README.rst
index 3881f2c..f01783a 100644
--- a/README.rst
+++ b/README.rst
@@ -37,3 +37,7 @@ Implementation Details
 * TLS is handled outside of sed for similar reasons. And to keep my sanity (some people might question whether I still have any bit of sanity left).
 * Likewise, SRV lookup and composition of the authentication data is entirely handled in bash. This also means that only PLAIN SASL authentication is supported -- SCRAM requires a level of interactivity which would be extremely hard to achieve in sed (not impossible though; we would "just" have to implement base64 and sha1-hmac in sed).
 * Since XMPP is a protocol where the client speaks first, we need to hand sed some initial input to allow it to generate a "line" of output (the stream header). We do that with bash, and use that opportunity to pass some configuration to the sed program (namely JID and authentication string).
+
+**Design Considerations**
+
+* We considered using ``xml2`` to convert the XML stream into events; however, it turns out that ``2xm[`` doesn’t like stream resets. Also, using the ``tr`` approach also allows us to detect the end of elements, which is useful for various purposes.