Support traffic distribute by request content

[simon-cj]

Now seldon core support traffic distribute by weight，but not support by content, eg: distribute by http Header.
in some case, it need to canny feature in online service, so suggest it that seldon core can support traffic distribute by request content.

[ukclivecox]

We could add this to the CRD but you can presently write your own Router to check the content/header and decide which child model to go to next.

[simon-cj]

Yes, we think so, we will write proposal to seldon community, hope that the community will be reviewed at that time.

[ukclivecox]

Will will support this in V2 APIs which will be agnostic to service mesh so you can use istio or whatever to split traffic. This is also possible now if you run AB tests at the istio level.

[ukclivecox]

Can you retry this with the v2 APIs