go.uber.org/yarpc@v1.72.1/api/peer/transport.go (about)

     1  // Copyright (c) 2022 Uber Technologies, Inc.
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    20  
    21  package peer
    22  
    23  // Subscriber listens to changes of a Peer over time.
    24  type Subscriber interface {
    25  	// The Peer Notifies the Subscriber when its status changes (e.g.
    26  	// connections status, pending requests)
    27  	//
    28  	// NotifyStatusChanged may call methods of the corresponding Peer,
    29  	// particularly Status.
    30  	// So, subscriber methods must not be called while holding a lock on the
    31  	// Transport.
    32  	NotifyStatusChanged(Identifier)
    33  }
    34  
    35  // Transport manages Peers across different Subscribers.
    36  //
    37  // A Subscriber will request a Peer for a specific PeerIdentifier and the
    38  // Transport has the ability to create a new Peer or return an existing one.
    39  //
    40  // RetainPeer and ReleasePeer must not call or synchronize with goroutines that
    41  // call methods of the Subscriber.
    42  type Transport interface {
    43  	// Get or create a Peer for the Subscriber
    44  	RetainPeer(Identifier, Subscriber) (Peer, error)
    45  
    46  	// Unallocate a peer from the Subscriber
    47  	ReleasePeer(Identifier, Subscriber) error
    48  }