rename models to pkg (#2005)

pkg/util/metric/date_counter.go

@@ -0,0 +1,134 @@
+// Copyright 2017 fatedier, fatedier@gmail.com
+//
+// 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 metric
+
+import (
+	"sync"
+	"time"
+)
+
+type DateCounter interface {
+	TodayCount() int64
+	GetLastDaysCount(lastdays int64) []int64
+	Inc(int64)
+	Dec(int64)
+	Snapshot() DateCounter
+	Clear()
+}
+
+func NewDateCounter(reserveDays int64) DateCounter {
+	if reserveDays <= 0 {
+		reserveDays = 1
+	}
+	return newStandardDateCounter(reserveDays)
+}
+
+type StandardDateCounter struct {
+	reserveDays int64
+	counts      []int64
+
+	lastUpdateDate time.Time
+	mu             sync.Mutex
+}
+
+func newStandardDateCounter(reserveDays int64) *StandardDateCounter {
+	now := time.Now()
+	now = time.Date(now.Year(), now.Month(), now.Day(), 0, 0, 0, 0, now.Location())
+	s := &StandardDateCounter{
+		reserveDays:    reserveDays,
+		counts:         make([]int64, reserveDays),
+		lastUpdateDate: now,
+	}
+	return s
+}
+
+func (c *StandardDateCounter) TodayCount() int64 {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+
+	c.rotate(time.Now())
+	return c.counts[0]
+}
+
+func (c *StandardDateCounter) GetLastDaysCount(lastdays int64) []int64 {
+	if lastdays > c.reserveDays {
+		lastdays = c.reserveDays
+	}
+	counts := make([]int64, lastdays)
+
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.rotate(time.Now())
+	for i := 0; i < int(lastdays); i++ {
+		counts[i] = c.counts[i]
+	}
+	return counts
+}
+
+func (c *StandardDateCounter) Inc(count int64) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.rotate(time.Now())
+	c.counts[0] += count
+}
+
+func (c *StandardDateCounter) Dec(count int64) {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	c.rotate(time.Now())
+	c.counts[0] -= count
+}
+
+func (c *StandardDateCounter) Snapshot() DateCounter {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	tmp := newStandardDateCounter(c.reserveDays)
+	for i := 0; i < int(c.reserveDays); i++ {
+		tmp.counts[i] = c.counts[i]
+	}
+	return tmp
+}
+
+func (c *StandardDateCounter) Clear() {
+	c.mu.Lock()
+	defer c.mu.Unlock()
+	for i := 0; i < int(c.reserveDays); i++ {
+		c.counts[i] = 0
+	}
+}
+
+// rotate
+// Must hold the lock before calling this function.
+func (c *StandardDateCounter) rotate(now time.Time) {
+	now = time.Date(now.Year(), now.Month(), now.Day(), 0, 0, 0, 0, now.Location())
+	days := int(now.Sub(c.lastUpdateDate).Hours() / 24)
+
+	defer func() {
+		c.lastUpdateDate = now
+	}()
+
+	if days <= 0 {
+		return
+	} else if days >= int(c.reserveDays) {
+		c.counts = make([]int64, c.reserveDays)
+		return
+	}
+	newCounts := make([]int64, c.reserveDays)
+
+	for i := days; i < int(c.reserveDays); i++ {
+		newCounts[i] = c.counts[i-days]
+	}
+	c.counts = newCounts
+}