Re: [libvirt] [PATCH 1/2] python: treat flags as default argument with value 0

On 03/21/2013 09:24 PM, Guannan Ren wrote: >>> migrate(self, dconn, flags, dname, uri, bandwidth): >>> migrate2(self, dconn, dxml, flags, dname, uri, bandwidth): >>> migrateToURI(self, duri, flags, dname, bandwidth): >>> migrateToURI2(self, dconnuri, miguri, dxml, flags, dname, bandwidth): >> So how are they filtered? ... >> > If we add flags=0 to above four APIs, we have to move the > flags arguments > to the last position in the arguments list because the rule > "default arguments > have to come after positional arguments." Changing them will > break the binding > APIs. so I didn't touch them. Actually, we should probably use migrate(self, dconn, flags=0, dname=None, uri=None, bandwidth=0) with sane defaults for all arguments after the flags. After all, the C api states: * virDomainMigrate: * @domain: a domain object * @dconn: destination host (a connection object) * @flags: bitwise-OR of virDomainMigrateFlags * @dname: (optional) rename domain to this at destination * @uri: (optional) dest hostname/URI as seen from the source host * @bandwidth: (optional) specify migration bandwidth limit in Mbps But I'm okay if you change the migrate* functions in a separate patch, since it will be touching more than just flags.

>> ...As I see you write "flags=0" for all the automatically generated >> APIs here? And is there any risk to have other APIs of which flags >> doesn't default to 0? Except the ones you mentioned in commit log. >> > > Yes, I am not sure if the 0 is appropriatefor every APIs. > I need more advice here. > According to my test, they can accept the 0 value all. flags == 0 should be sane for all APIs that we add. In fact, for many APIs, flags == 0 is the only value that we actually support, when we haven't yet used any flags.