Description
Currently the "Explorer/Spans" is kind of hard to digest. As a user, if choosing a service name, I'd like to chose it from a list instead of having to write it down the name:
This makes totally sense as service names is low cardinality and you can know them on before hand, also having to a typo on the service name can lead you to think there are no traces. For example in zipkin we show the list of services:
Once the service name is selected, we should refine the possibilities for Service Name as it only make sense to choose between those span names related to the service:
While I chose zipkin to show examples on this, UIs like Haystack or jaeger do this too
This is a couple of basic suggestions but in general everything that is low cardinality should be listed as it improves highly the user experience.
Same applies for known tags that we know are low cardinality e.g. status code or http method
Related issue: hypertrace/hypertrace#109