1
  2
  3
  4
  5
  6
  7
  8
  9
 10
 11
 12
 13
 14
 15
 16
 17
 18
 19
 20
 21
 22
 23
 24
 25
 26
 27
 28
 29
 30
 31
 32
 33
 34
 35
 36
 37
 38
 39
 40
 41
 42
 43
 44
 45
 46
 47
 48
 49
 50
 51
 52
 53
 54
 55
 56
 57
 58
 59
 60
 61
 62
 63
 64
 65
 66
 67
 68
 69
 70
 71
 72
 73
 74
 75
 76
 77
 78
 79
 80
 81
 82
 83
 84
 85
 86
 87
 88
 89
 90
 91
 92
 93
 94
 95
 96
 97
 98
 99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155

use dbui_core::ResponseMessage;

use std::collections::{HashMap, HashSet};
use uuid::Uuid;

pub trait SendCallback: Sync + Send {
  fn send_message(&self, msg: ResponseMessage) -> ();
}

pub struct ConnectionCache {
  connections: HashMap<Uuid, Box<dyn SendCallback>>,
  channels: HashMap<String, HashSet<Uuid>>,
  log: slog::Logger
}

impl std::fmt::Debug for ConnectionCache {
  fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
    write!(
      f,
      "ConnectionCache [{}] connections, [{}] channels",
      &self.connections.len(),
      &self.channels.len()
    )
  }
}

impl ConnectionCache {
  pub fn new(log: &slog::Logger) -> ConnectionCache {
    let log = log.new(slog::o!("service" => "connection-cache"));
    slog::debug!(log, "Connection cache created");
    ConnectionCache {
      connections: HashMap::new(),
      channels: HashMap::new(),
      log
    }
  }

  pub fn conn_list(&self) -> Vec<Uuid> {
    let mut conns: Vec<Uuid> = self.connections.keys().copied().collect();
    conns.sort();
    conns
  }

  pub fn channel_list(&self) -> Vec<(String, Vec<Uuid>)> {
    let mut channels: Vec<(String, Vec<Uuid>)> = self
      .channels
      .iter()
      .map(|v| {
        let mut ids: Vec<Uuid> = v.1.iter().copied().collect();
        ids.sort();
        (v.0.clone(), ids)
      })
      .collect();
    channels.sort();
    channels
  }

  pub fn add<F>(&mut self, key: &str, id: Uuid, f: Box<dyn SendCallback>) {
    let _ = self.connections.insert(id, f);
    match self.channels.get_mut(key) {
      Some(current) => {
        slog::debug!(
          self.log,
          "Adding additional connection [{}] to [{}], which has [{}] existing connections",
          id,
          key,
          current.len()
        );
        let _ = current.insert(id);
      }
      None => {
        slog::debug!(self.log, "Adding first connection [{}] to [{}]", id, key);
        let set: HashSet<Uuid> = vec![id].into_iter().collect();
        let _ = self.channels.insert(key.into(), set);
      }
    }
  }

  pub fn remove(&mut self, key: &str, id: Uuid) {
    let _ = self.connections.remove(&id);
    match self.channels.get_mut(key) {
      Some(current) => {
        if current.contains(&id) {
          let _ = current.remove(&id);
          slog::debug!(
            self.log,
            "Removed connection [{}] from [{}], leaving [{}] other connections",
            id,
            key,
            current.len()
          )
        } else {
          slog::debug!(
            self.log,
            "Could not find connection [{}] for [{}] among [{}] other connections",
            id,
            key,
            current.len()
          )
        }
      }
      None => slog::debug!(
        self.log,
        "Attempt to remove connection [{}] from [{}], which has no connections",
        id,
        key
      )
    }
  }

  pub fn send_connection(&self, id: &Uuid, msg: ResponseMessage) {
    match &mut self.connections.get(id) {
      Some(f) => {
        slog::debug!(self.log, "Sending message [{:?}] to connection [{}]", msg, &id);
        f.send_message(msg);
      }
      None => slog::warn!(self.log, "Message send attempted for missing connection [{}]", &id)
    }
  }

  pub fn send_channel(&self, key: &str, msg: ResponseMessage) {
    self.send_channel_except(key, vec![], msg)
  }

  pub fn send_channel_except(&self, key: &str, exclude: Vec<&Uuid>, msg: ResponseMessage) {
    match &mut self.channels.get(key) {
      Some(current) => {
        let size = current.len();
        let filtered: Vec<&Uuid> = current
          .iter()
          .filter(|c| {
            println!("{:?} / {} == {}", exclude, c, !exclude.contains(c));
            !exclude.contains(c)
          })
          .collect();
        slog::debug!(
          self.log,
          "Sending message [{:?}] to [{}], using [{} of {}] connections",
          msg,
          key,
          filtered.len(),
          size
        );
        let _: Vec<_> = filtered
          .iter()
          .map(|id| match self.connections.get(id) {
            Some(f) => f.send_message(msg.clone()),
            None => slog::warn!(self.log, "Unable to send message")
          })
          .collect();
      }
      None => ()
    }
  }
}