func (s *DiscoverySuite) TestWatch(c *check.C) {
d := &Discovery{}
d.Initialize("1.1.1.1:1111,2.2.2.2:2222", 0, 0, nil)
expected := discovery.Entries{
&discovery.Entry{Host: "1.1.1.1", Port: "1111"},
&discovery.Entry{Host: "2.2.2.2", Port: "2222"},
}
ch, _ := d.Watch(nil)
c.Assert(expected.Equals(<-ch), check.Equals, true)
}
func TestWatch(t *testing.T) {
d := &Discovery{}
d.Initialize("1.1.1.1:1111,2.2.2.2:2222", 0, 0)
expected := discovery.Entries{
&discovery.Entry{Host: "1.1.1.1", Port: "1111"},
&discovery.Entry{Host: "2.2.2.2", Port: "2222"},
}
ch, _ := d.Watch(nil)
assert.True(t, expected.Equals(<-ch))
}
// Entries are Docker Engines
func (c *Cluster) monitorDiscovery(ch <-chan discovery.Entries, errCh <-chan error) {
// Watch changes on the discovery channel.
currentEntries := discovery.Entries{}
for {
select {
case entries := <-ch:
added, removed := currentEntries.Diff(entries)
currentEntries = entries
// Remove engines first. `addEngine` will refuse to add an engine
// if there's already an engine with the same ID. If an engine
// changes address, we have to first remove it then add it back.
for _, entry := range removed {
c.removeEngine(entry.String())
}
for _, entry := range added {
c.addEngine(entry.String())
}
case err := <-errCh:
log.Errorf("Discovery error: %v", err)
}
}
}