make notification as separate package (#5294)

* Remove old notification files

* Add net package

* Add event package

* Modify minio to take new notification system

pkg/event/rulesmap.go

@@ -0,0 +1,78 @@
+/*
+ * Minio Cloud Storage, (C) 2018 Minio, Inc.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package event
+
+// RulesMap - map of rules for every event name.
+type RulesMap map[Name]Rules
+
+// add - adds event names, prefixes, suffixes and target ID to rules map.
+func (rulesMap RulesMap) add(eventNames []Name, pattern string, targetID TargetID) {
+	rules := make(Rules)
+	rules.Add(pattern, targetID)
+
+	for _, eventName := range eventNames {
+		for _, name := range eventName.Expand() {
+			rulesMap[name] = rulesMap[name].Union(rules)
+		}
+	}
+}
+
+// Clone - returns copy of this rules map.
+func (rulesMap RulesMap) Clone() RulesMap {
+	rulesMapCopy := make(RulesMap)
+
+	for eventName, rules := range rulesMap {
+		rulesMapCopy[eventName] = rules.Clone()
+	}
+
+	return rulesMapCopy
+}
+
+// Add - adds given rules map.
+func (rulesMap RulesMap) Add(rulesMap2 RulesMap) {
+	for eventName, rules := range rulesMap2 {
+		rulesMap[eventName] = rules.Union(rulesMap[eventName])
+	}
+}
+
+// Remove - removes given rules map.
+func (rulesMap RulesMap) Remove(rulesMap2 RulesMap) {
+	for eventName, rules := range rulesMap {
+		if nr := rules.Difference(rulesMap2[eventName]); len(nr) != 0 {
+			rulesMap[eventName] = nr
+		} else {
+			delete(rulesMap, eventName)
+		}
+	}
+}
+
+// Match - returns TargetIDSet matching object name and event name in rules map.
+func (rulesMap RulesMap) Match(eventName Name, objectName string) TargetIDSet {
+	return rulesMap[eventName].Match(objectName)
+}
+
+// NewRulesMap - creates new rules map with given values.
+func NewRulesMap(eventNames []Name, pattern string, targetID TargetID) RulesMap {
+	// If pattern is empty, add '*' wildcard to match all.
+	if pattern == "" {
+		pattern = "*"
+	}
+
+	rulesMap := make(RulesMap)
+	rulesMap.add(eventNames, pattern, targetID)
+	return rulesMap
+}