Order attributes in generated tables by requirement level

[pyohannes]

When consulting semantic conventions and the documentation generated from it, especially for metrics, I often find myself asking which attributes I can rely on to be present (which ones are "required"). For me, that's a much more common use case than looking for a single attribute by name.

Therefore I suggest to change the ordering of generated attribute tables to order by requirement level: required attributes first, then conditionally required ones, recommended ones, and opt-ins. Find below an example of how that would look for http.server.request.duration attributes.

If there's consensus about this, I could implement the necessary changes in the build tools.

Example

Attribute	Type	Description	Examples	Requirement Level
http.request.method	string	HTTP request method. [1]	GET; POST; HEAD	Required
url.scheme	string	The URI scheme component identifying the used protocol. [2]	http; https	Required
error.type	string	Describes a class of error the operation ended with. [3]	timeout; java.net.UnknownHostException; server_certificate_invalid; 500	Conditionally Required: If request has ended with an error.
http.response.status_code	int	HTTP response status code.	200	Conditionally Required: If and only if one was received/sent.
http.route	string	The matched route, that is, the path template in the format used by the respective server framework. [4]	/users/:userID?; {controller}/{action}/{id?}	Conditionally Required: If and only if it's available
network.protocol.name	string	OSI application layer or non-OSI equivalent. [5]	http; spdy	Conditionally Required: [6]
network.protocol.version	string	Version of the protocol specified in network.protocol.name. [7]	1.0; 1.1; 2; 3	Recommended
server.address	string	Name of the local HTTP server that received the request. [8]	example.com; 10.1.2.80; /tmp/my.sock	Opt-In
server.port	int	Port of the local HTTP server that received the request. [9]	80; 8080; 443	Opt-In

[marcalff]

Or even better, generate HTML tables that are sortable in the browser, so the reader can click on a column to sort by attribute name / type / requirement level / ...

[lmolkova]

Totally support this. I think we should order on both to keep stable order:

• req level
• name within one requirement level