gateway

Documentation

Overview

Package gateway is the MCP gateway core. It terminates streamable-HTTP on the front, runs every message through the inspection pipeline, then routes to one or more backends (aggregating with tool prefixes when several).

Index

• type Gateway
  • func New(opts Options) (*Gateway, error)
  • func (g *Gateway) Close()
  • func (g *Gateway) Handler() http.Handler
• type HeldCall
• type HeldStore
• type IdentityResolver
• type Observer
• type Options

Types

type Gateway

type Gateway struct {
	// contains filtered or unexported fields
}

Gateway is the shared front for all sessions.

func New

func New(opts Options) (*Gateway, error)

New builds a Gateway.

func (*Gateway) Close

func (g *Gateway) Close()

Close terminates all sessions.

func (*Gateway) Handler

func (g *Gateway) Handler() http.Handler

Handler returns the streamable-HTTP front: POST = one JSON-RPC message, GET = SSE stream of server-initiated messages, DELETE = end session.

type HeldCall

type HeldCall struct {
	Session string
	User    string
	Backend string
	Tool    string
	Args    []byte
	Rule    string
}

HeldCall describes one parked tool call.

type HeldStore

type HeldStore interface {
	// Hold parks a call and returns a resolution channel. The channel
	// yields true (approved) or false (rejected) exactly once.
	Hold(ctx context.Context, h HeldCall) (id string, resolved <-chan bool, err error)
}

HeldStore parks messages awaiting human approval.

type IdentityResolver

type IdentityResolver func(r *http.Request) (inspect.Identity, error)

IdentityResolver authenticates an HTTP request (inbound auth). It returns the caller identity or an error that terminates the request. The gateway stays auth-agnostic: the daemon (or hoop) supplies the resolver.

type Observer

type Observer interface {
	ObserveMessage(dir inspect.Direction, backendName, method, tool, decision string, dur time.Duration)
}

Observer is the telemetry seam: one call per gateway-processed message.

type Options

type Options struct {
	// Backends: name → factory. Names are tool prefixes in aggregation.
	Backends map[string]backend.Factory
	// Pipeline is the ordered check chain applied to every message.
	Pipeline []inspect.Check
	// Resolver authenticates requests. nil = anonymous.
	Resolver IdentityResolver
	// Sink receives audit events. nil = discard.
	Sink audit.Sink
	// SessionIdleTimeout reaps sessions with no traffic. 0 = 30m.
	SessionIdleTimeout time.Duration
	// RequestTimeout bounds one round-trip to a backend. 0 = 5m, since
	// slow tool calls are normal. Approvals hold longer via ctx.
	RequestTimeout time.Duration
	// Held is the approval parking lot; nil disables Hold verdicts
	// (they become Deny).
	Held HeldStore
	// Observer receives per-message timing/decision telemetry. Optional.
	Observer Observer
	Logger   *slog.Logger
}

Options assemble a Gateway.