cluster_constraints

Summary

A ClusterConstraint describes a filtering of the Instances in a Cluster based on their Metadata. Instances in the keyed cluster with a superset of the specified Metadata will be included. The Weight of the ClusterConstraint is used to inform selection of one ClusterConstraint over another.

Example object

{
    "constraint_key": "constraint-key-1",
    "cluster_key": "passthrough-cluster-3",
    "metadata": null,
    "properties": null,
    "response_data": {},
    "weight": 1
}

Fields

constraint_key

A string value to uniquely identify this constraint in the API.

cluster_key

The key of the cluster that matching requests will be sent to.

metadata

Array of {"key": "", "value": } pairs that mush match on the intended cluster.

properties

This field has no effect.

response_data

Array of Response data

weight

This field determines how traffic is distributed among the members of the constraint, but it has different interpretations depending on if it's used in light or dark constraints.

light

When used in the light constraint, it will be the relative weight expressed as an integer. This is because light traffic must always represent 100%, so any weights are totaled and divided among the members to determining fractional routing.

dark

When used in the dark constraint, it will be the percentage of traffic expressed as an integer. This is because dark traffic does not need to equal 100%; one shadow cluster may get 10% of traffic and another 40%, or whatever spread makes sense to the application.