const (
    // AuthzCustom is the name of the authorization plugin (CUSTOM action) passed through the command line
    AuthzCustom = "ext_authz"
    // Authn is the name of the authentication plugin passed through the command line
    Authn = "authn"
    // Authz is the name of the authorization plugin (ALLOW/DENY/AUDIT action) passed through the command line
    Authz = "authz"
    // MetadataExchange is the name of the telemetry plugin passed through the command line
    MetadataExchange = "metadata_exchange"
)

type InputParams struct {
    // ListenerProtocol is the protocol/class of listener (TCP, HTTP etc.). Must be set.
    // This is valid only for the inbound listener
    // Outbound listeners could have multiple filter chains, where one filter chain could be
    // a HTTP connection manager with TLS context, while the other could be a tcp proxy with sni
    ListenerProtocol istionetworking.ListenerProtocol
    // Node is the node the response is for.
    Node *model.Proxy
    // ServiceInstance is the service instance colocated with the listener (applies to sidecar).
    ServiceInstance *model.ServiceInstance
    // Push holds stats and other information about the current push.
    Push *model.PushContext
}

type Plugin interface {
    // OnOutboundListener is called whenever a new outbound listener is added to the LDS output for a given service.
    // Can be used to add additional filters on the outbound path.
    OnOutboundListener(in *InputParams, mutable *istionetworking.MutableObjects) error

    // OnInboundListener is called whenever a new listener is added to the LDS output for a given service
    // Can be used to add additional filters.
    OnInboundListener(in *InputParams, mutable *istionetworking.MutableObjects) error

    // OnInboundFilterChains is called whenever a plugin needs to setup the filter chains, including relevant filter chain
    // configuration, like FilterChainMatch and TLSContext.
    OnInboundFilterChains(in *InputParams) []istionetworking.FilterChain

    // OnInboundPassthrough is called whenever a new passthrough filter chain is added to the LDS output.
    // Can be used to add additional filters.
    OnInboundPassthrough(in *InputParams, mutable *istionetworking.MutableObjects) error

    // OnInboundPassthroughFilterChains is called whenever a plugin needs to setup custom pass through filter chain.
    OnInboundPassthroughFilterChains(in *InputParams) []istionetworking.FilterChain
}