71 lines
1.8 KiB
Go
71 lines
1.8 KiB
Go
// Package broker is an interface used for asynchronous messaging
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package broker
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import (
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"context"
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"errors"
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"github.com/unistack-org/micro/v3/metadata"
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)
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// DefaultBroker default broker
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var DefaultBroker Broker = NewBroker()
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// Broker is an interface used for asynchronous messaging.
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type Broker interface {
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Name() string
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Init(...Option) error
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Options() Options
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Address() string
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Connect(context.Context) error
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Disconnect(context.Context) error
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Publish(context.Context, string, *Message, ...PublishOption) error
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Subscribe(context.Context, string, Handler, ...SubscribeOption) (Subscriber, error)
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String() string
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}
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// Handler is used to process messages via a subscription of a topic.
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type Handler func(Event) error
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// Event is given to a subscription handler for processing
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type Event interface {
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Topic() string
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Message() *Message
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Ack() error
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Error() error
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}
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// RawMessage is a raw encoded JSON value.
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// It implements Marshaler and Unmarshaler and can be used to delay decoding or precompute a encoding.
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type RawMessage []byte
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// MarshalJSON returns m as the JSON encoding of m.
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func (m *RawMessage) MarshalJSON() ([]byte, error) {
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if m == nil {
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return []byte("null"), nil
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}
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return *m, nil
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}
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// UnmarshalJSON sets *m to a copy of data.
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func (m *RawMessage) UnmarshalJSON(data []byte) error {
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if m == nil {
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return errors.New("RawMessage UnmarshalJSON on nil pointer")
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}
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*m = append((*m)[0:0], data...)
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return nil
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}
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// Message is used to transfer data
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type Message struct {
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Header metadata.Metadata // contains message metadata
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Body RawMessage // contains message body
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}
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// Subscriber is a convenience return type for the Subscribe method
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type Subscriber interface {
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Options() SubscribeOptions
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Topic() string
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Unsubscribe(context.Context) error
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}
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