Initial commit

collection.go

@@ -0,0 +1,69 @@
+package main
+
+import (
+	"sync"
+)
+
+// Collection is sync.Map, that stores arbitrary data.
+type Collection struct {
+	items sync.Map
+	close chan struct{}
+}
+
+// Item just interface for stoing any data.
+type item struct {
+	data interface{}
+}
+
+// NewCollection creates new instance of "collection".
+func NewCollection() *Collection {
+	c := &Collection{ //nolint:exhaustruct
+		close: make(chan struct{}),
+	}
+
+	return c
+}
+
+// Get returns value by given key. Or empty value.
+func (collection *Collection) Get(key interface{}) (interface{}, bool) {
+	obj, exists := collection.items.Load(key)
+
+	if !exists {
+		return nil, false
+	}
+
+	item := obj.(item)
+
+	return item.data, true
+}
+
+// Set saves value to given "collection".
+func (collection *Collection) Set(key interface{}, value interface{}) {
+	collection.items.Store(key, item{
+		data: value,
+	})
+}
+
+// Range apply function f to all keys/values in collection. Retuns immediatly on first error.
+func (collection *Collection) Range(f func(key, value interface{}) bool) {
+	fn := func(key, value interface{}) bool {
+		item := value.(item)
+
+		return f(key, item.data)
+	}
+
+	collection.items.Range(fn)
+}
+
+// Delete deletes key and corresponding value from collection.
+func (collection *Collection) Delete(key interface{}) {
+	collection.items.Delete(key)
+}
+
+// Close frees memory occupied by collection and deletes collection itself.
+func (collection *Collection) Close() {
+	collection.close <- struct{}{}
+	collection.items = sync.Map{}
+}
+
+/* vim: set ft=go noet ai ts=4 sw=4 sts=4: */