The MQTT device factory adds topic segments to the mapping context, e.g. foo/bar gives context.topic-0 set to foo.
This was failing if the the topic was starting with a /, e.g. /foo/bar.
This PR fixes the segmentation process, following the MQTT specification:
/foo, foo and foo/ are different
with a / prefix, context.topic-0 is always an empty string
with a / suffix, context.topic-last is always an empty string
foo/bar and foo//bar are equivalent, but foo/bar and foo/ /bar are different (and context.topic-1 will be a space character)
The MQTT device factory adds topic segments to the mapping context, e.g.
foo/bargivescontext.topic-0set tofoo. This was failing if the the topic was starting with a/, e.g./foo/bar.This PR fixes the segmentation process, following the MQTT specification:
/foo,fooandfoo/are different/prefix,context.topic-0is always an empty string/suffix,context.topic-lastis always an empty stringfoo/barandfoo//barare equivalent, butfoo/barandfoo/ /barare different (andcontext.topic-1will be a space character)