In-memory reaper. TtlSet needs tests.

lib/units/reaper/index.js

@@ -4,18 +4,43 @@ var zmq = require('zmq')
 var logger = require('../../util/logger')
 var wire = require('../../wire')
 var wireutil = require('../../wire/util')
+var wirerouter = require('../../wire/router')
 var dbapi = require('../../db/api')
 var lifecycle = require('../../util/lifecycle')
 var srv = require('../../util/srv')
 
+var TtlSet = require('./util/ttlset')
+
 module.exports = function(options) {
   var log = logger.createLogger('reaper')
-    , timer
+  var ttlset = new TtlSet(options.heartbeatTimeout)
 
   if (options.name) {
     logger.setGlobalIdentifier(options.name)
   }
 
+  // Input
+  var sub = zmq.socket('sub')
+  Promise.map(options.endpoints.sub, function(endpoint) {
+    return srv.resolve(endpoint).then(function(records) {
+      return srv.attempt(records, function(record) {
+        log.info('Receiving input from "%s"', record.url)
+        sub.connect(record.url)
+        return Promise.resolve(true)
+      })
+    })
+  })
+  .catch(function(err) {
+    log.fatal('Unable to connect to sub endpoint', err)
+    lifecycle.fatal()
+  })
+
+  // Establish always-on channels
+  ;[wireutil.global].forEach(function(channel) {
+    log.info('Subscribing to permanent channel "%s"', channel)
+    sub.subscribe(channel)
+  })
+
   // Output
   var push = zmq.socket('push')
   Promise.map(options.endpoints.push, function(endpoint) {
@@ -32,39 +57,55 @@ module.exports = function(options) {
     lifecycle.fatal()
   })
 
-  function reap() {
-    dbapi.getDeadDevices(options.heartbeatTimeout)
-      .then(function(cursor) {
-        return Promise.promisify(cursor.toArray, cursor)()
-          .then(function(list) {
-            list.forEach(function(device) {
-              log.info('Reaping device "%s"', device.serial)
-              push.send([
-                wireutil.global
-              , wireutil.envelope(new wire.DeviceAbsentMessage(
-                  device.serial
-                ))
-              ])
-            })
-          })
-      })
-      .catch(function(err) {
-        log.error('Failed to load device list: ', err.message, err.stack)
-        lifecycle.fatal()
-      })
-  }
+  sub.on('message', wirerouter()
+    .on(wire.DevicePresentMessage, function(channel, message) {
+      ttlset.bump(message.serial, Date.now())
+    })
+    .on(wire.DeviceHeartbeatMessage, function(channel, message) {
+      ttlset.bump(message.serial, Date.now())
+    })
+    .on(wire.DeviceAbsentMessage, function(channel, message) {
+      ttlset.drop(message.serial)
+    })
+    .handler())
+
+  ttlset.on('timeout', function(serial) {
+    log.info('Reaping device "%s" due to heartbeat timeout', serial)
+    push.send([
+      wireutil.global
+    , wireutil.envelope(new wire.DeviceAbsentMessage(
+        serial
+      ))
+    ])
+  })
+
+  dbapi.loadPresentDevices()
+    .then(function(cursor) {
+      return Promise.promisify(cursor.toArray, cursor)()
+        .then(function(list) {
+          var now = Date.now()
+          list.forEach(function(device) {
+            ttlset.bump(device.serial, now)
+          })
+        })
+    })
+    .catch(function(err) {
+      log.error('Failed to load device list: ', err.stack)
+      lifecycle.fatal()
+    })
 
-  timer = setInterval(reap, options.reapInterval)
   log.info('Reaping devices with no heartbeat')
 
   lifecycle.observe(function() {
-    clearTimeout(timer)
+    [push, sub].forEach(function(sock) {
+      try {
+        sock.close()
+      }
+      catch (err) {
+        // No-op
+      }
+    })
 
-    try {
-      push.close()
-    }
-    catch (err) {
-      // No-op
-    }
+    ttlset.stop()
   })
 }