call_option.go

// Copyright (c) 2017 Uber Technologies, Inc.
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// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
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// THE SOFTWARE.

package encoding

// CallOption defines options that may be passed in at call sites to other
// services.
//
// Encoding authors should accept yarpc.CallOptions and convert them to
// encoding.CallOptions to use with NewOutboundCall. This will keep the
// API for service authors simple.
type CallOption struct{ apply func(*OutboundCall) }

// ResponseHeaders specifies that headers received in response to this request
// should replace the given map.
func ResponseHeaders(h *map[string]string) CallOption {
	return CallOption{func(o *OutboundCall) { o.responseHeaders = h }}
}

// WithHeader adds a new header to the request.
func WithHeader(k, v string) CallOption {
	return CallOption{func(o *OutboundCall) {
		o.headers = append(o.headers, keyValuePair{k: k, v: v})
	}}
}

// WithShardKey sets the shard key for the request.
func WithShardKey(sk string) CallOption {
	return CallOption{func(o *OutboundCall) { o.shardKey = &sk }}
}

// WithRoutingKey sets the routing key for the request.
func WithRoutingKey(rk string) CallOption {
	return CallOption{func(o *OutboundCall) { o.routingKey = &rk }}
}

// WithRoutingDelegate sets the routing delegate for the request.
func WithRoutingDelegate(rd string) CallOption {
	return CallOption{func(o *OutboundCall) { o.routingDelegate = &rd }}
}