go-micro client 客户端

// Client is the interface used to make requests to services.
// It supports Request/Response via Transport and Publishing via the Broker.
// It also supports bidiectional streaming of requests.
type Client interface {
	Init(...Option) error
	Options() Options
	NewMessage(topic string, msg interface{}, opts ...MessageOption) Message
	NewRequest(service, method string, req interface{}, reqOpts ...RequestOption) Request
	Call(ctx context.Context, req Request, rsp interface{}, opts ...CallOption) error
	Stream(ctx context.Context, req Request, opts ...CallOption) (Stream, error)
	Publish(ctx context.Context, msg Message, opts ...PublishOption) error
	String() string
}

// Message is the interface for publishing asynchronously
type Message interface {
	Topic() string
	Payload() interface{}
	ContentType() string
}

// Request is the interface for a synchronous request used by Call or Stream
type Request interface {
	Service() string
	Method() string
	ContentType() string
	Request() interface{}
	// indicates whether the request will be a streaming one rather than unary
	Stream() bool
}

// Stream is the inteface for a bidirectional synchronous stream
type Stream interface {
	Context() context.Context
	Request() Request
	Send(interface{}) error
	Recv(interface{}) error
	Error() error
	Close() error
}

// Option used by the Client
type Option func(*Options)

// CallOption used by Call or Stream
type CallOption func(*CallOptions)

// PublishOption used by Publish
type PublishOption func(*PublishOptions)

// MessageOption used by NewMessage
type MessageOption func(*MessageOptions)

// RequestOption used by NewRequest
type RequestOption func(*RequestOptions)