On quinta-feira, 4 de fevereiro de 2016 16:50:11 PST Subramaniam, Ravi wrote: > So giving the client having the option of sending a request without a query > portion eases things significantly. When a server indicates the default > interface all it is telling the Client - "if you send me a request without > a query part then I will interpret that request as if you sent it to the > Interface I am telling you is my default" - this makes the semantics of a > simple no query request explicit, I don't think the Server is forcing use > of the default or selecting an Interface for the Client. Now this default > is chosen such that a simple request without query would cover the largest > kind of requests expected against the Resource. Given this the Core chose a > simple mechanism to communicate the default by using ordering in the > discovery response; discovery must be done anyway (whether or not we have > default) so that the Client can know which Interfaces it can select from. > So there is no extra burden to the Client from designating the default - it > just makes it easier for Client to formulate a request in *all* cases i.e. > cases with Collections. > > Now if the Client uses the default semantics fully then we get additional > benefits like MTU etc.
Hello Ravi I understand what you're saying, but I will repeat here what I told Mitch: I don't think the default of the server will factor into the client's decision making of which interface to use. If the client supports parsing interfaces A, B and C, and the server supports interfaces A, B and D, it's clear that the communication will be handled via either A or B. Moreover, the *client* chooses which interface to use when querying. Since the default can be either A or B, depending on the manufacturer, firmware version, boot order, or the phase of the moon (think of a salted hash), it's simpler logic for the client to always pass ?if=A and ?if=B when it wants that one. It will never rely on the default. So I repeat what I said: making the default vary from device to device is, at best, a zero gain in having a default at all, and at worse it's a red herring causing confusion. -- Thiago Macieira - thiago.macieira (AT) intel.com Software Architect - Intel Open Source Technology Center
