weight

Splits the traffic of a group of routes by share. This is the canary: the same path, two upstreams, most of the traffic on the version in production and a little on the new one.

Parameters

Name	Type	Required	What it does
`group`	string	yes	The name the routes of one split share.
`weight`	integer	yes	This route's share of the group. Must be greater than zero.

A route takes a share of the requests: its weight divided by the total of the group. The numbers are shares, not percentages: 8 and 2 is the same split as 80 and 20.

Example

The full configuration

routes:
  - id: checkout
    name: Checkout
    enabled: true
    order: 100
    upstream: http://checkout-1.internal:8080
    predicates:
      - type: path
        args:
          patterns:
            - /checkout/**
      - type: weight
        args:
          group: checkout
          weight: 8
  - id: checkout-next
    name: Checkout (next)
    enabled: true
    order: 110
    upstream: http://checkout-2.internal:8080
    predicates:
      - type: path
        args:
          patterns:
            - /checkout/**
      - type: weight
        args:
          group: checkout
          weight: 2

One request in five goes to the new version.

Notes

The draw happens per request, so one person sees both versions during a session. Add a cookie predicate on a route of the group when someone has to stay on one side.

Shares are computed over the routes actually loaded, so disabling a route of the group hands its share to the others rather than dropping that traffic.

The other predicates still apply: a route only takes its share of the requests its own path, host and method already accepted.