github.com/google/fleetspeak@v0.1.15-0.20240426164851-4f31f62c1aea/fleetspeak/src/server/notifications/notifications.go (about)

     1  // Copyright 2018 Google Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     https://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  // Package notifications defines the plugin interface for components which allow
    16  // the fleetspeak servers within an installation to notify each other about
    17  // interesting events.
    18  package notifications
    19  
    20  import (
    21  	"context"
    22  
    23  	"github.com/google/fleetspeak/fleetspeak/src/common"
    24  )
    25  
    26  type Listener interface {
    27  	// Start causes the Listener to begin listening for notifications. Once
    28  	// started, should write to ids every time it is notified that there may be
    29  	// new messages for a client.
    30  	Start() (<-chan common.ClientID, error)
    31  
    32  	// Stop causes the Listener to stop listening for notifications and close the
    33  	// ids channel.
    34  	Stop()
    35  
    36  	// Address returns the address of this listener. These addresses must be
    37  	// suitable to pass as a target to any Notifier compatible with this Listener.
    38  	// Will only be called after Start().
    39  	Address() string
    40  }
    41  
    42  type Notifier interface {
    43  	// NewMessageForClient indicates that one or more messages have been written
    44  	// and notifies the provided target of this.
    45  	NewMessageForClient(ctx context.Context, target string, id common.ClientID) error
    46  }