Case sensitive params

[Zarquan]

Allowing param names to be case insensitive makes it harder to write a DALI compatible service using modern development frameworks.

DALI/DALI.tex

Lines 580 to 586 in f86401e

	\subsection{Case Sensitivity}
	Parameter names are not case sensitive; a DAL service must treat
	\hbox{upper-,} \hbox{lower-,}
	and mixed-case parameter names as equal. Parameter values are case sensitive
	unless a concrete DAL service specification explicitly states that the values of
	a specific parameter are to be treated as case-insensitive. For example, the
	following are equivalent:

Almost all of the current development tools assume that param names will be case sensitive. This adds yet another bit of friction that new developers have to contend with.

[pdowler]

This is largely a historical issue; DALI is to a large extent a refactoring of existing practices (eg existing RECs) so that they become consistent practices... I don't disagree that this causes pain for developers, but I think the idea was to not cause pain for users.

Specifically, it combines with another common practice: services should ignore any params they don't grok so clients can add "junk" without breaking anything. The reason this is related is that you can't have this "silently ignore" and help users when they use the wrong case for a param name without making assumptions.... eg service accepts upper case POS={something} and a user might include "pos=circle 12 34 1" by mistake or they might intentionally include "pos=uncertain" to tag a request for their own purposes. The service can either ignore "pos" or give an error due to unknown parameter input (which might help the first case but break the second)