[regext] Feedback about breakage analysis

[Mario Loffredo <[e-mail]>]

Hi Jasdip,

I would suggest to add Approach C and split some scenarios into smaller 
changes.

I mean, some of the scenarios presented merge breaking and non-breaking 
changes.

I would classify the scenarios reflecting the basic breaking and 
non-breaking changes as in the following.

Possible breaking changes that can occur in the RDAP context include:

     Removing a response field
     Modifying a path URI
     Modifying a field name or type
     Modifying a required query parameter

While non-breaking changes include:

     Adding a path
     Adding a response field
     Adding an optional query parameter

Any combination of breaking changes should be treated as one 
non-breaking change while any combination including at least one 
breaking change should be treated as one breaking change (e.g., 
"Replacing jCard with JSCard" is equal to "Removing jCard " + "Adding 
JSCard").

That being said, anyone can realize that Approach A (at least as is for 
now) transforms the non-breaking changes in breaking ones. For example, 
defining a new version of a request extension by adding an optional 
query parameter to a given path implies that the path URI gets modified 
(@Jasdip, this scenario corresponds to the second one presented in your 
breakage analysis but limited only to the assumption "Query parameter q1 
added"). Likewise, adding a new member to a response extension would 
result in modifying the name of the response extension as well (@Jsdip, 
this seems to me not included in your breakage analysis).

For that reasons, I wouldn't opt for Apporach A.


Cheers,

Mario


-- 
Dr. Mario Loffredoto a
Technological Unit “Digital Innovation”
Institute of Informatics and Telematics (IIT)
National Research Council (CNR)
via G. Moruzzi 1, I-56124 PISA, Italy
Phone: [phone]
Web: http://www.iit.cnr.it/mario.loffredo