github.com/ryanslade/nomad@v0.2.4-0.20160128061903-fc95782f2089/nomad/watch/watch.go (about)

     1  package watch
     2  
     3  // The watch package provides a means of describing a watch for a blocking
     4  // query. It is exported so it may be shared between Nomad's RPC layer and
     5  // the underlying state store.
     6  
     7  // Item describes the scope of a watch. It is used to provide a uniform
     8  // input for subscribe/unsubscribe and notification firing. Specifying
     9  // multiple fields does not place a watch on multiple items. Each Item
    10  // describes exactly one scoped watch.
    11  type Item struct {
    12  	Alloc     string
    13  	AllocEval string
    14  	AllocJob  string
    15  	AllocNode string
    16  	Eval      string
    17  	Job       string
    18  	Node      string
    19  	Table     string
    20  }
    21  
    22  // Items is a helper used to construct a set of watchItems. It deduplicates
    23  // the items as they are added using map keys.
    24  type Items map[Item]struct{}
    25  
    26  // NewItems creates a new Items set and adds the given items.
    27  func NewItems(items ...Item) Items {
    28  	wi := make(Items)
    29  	for _, item := range items {
    30  		wi.Add(item)
    31  	}
    32  	return wi
    33  }
    34  
    35  // Add adds an item to the watch set.
    36  func (wi Items) Add(i Item) {
    37  	wi[i] = struct{}{}
    38  }