timedmap

README

~ timedmap ~

A map which has expiring key-value pairs.

       

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go get github.com/zekroTJA/timedmap

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Intro

This package allows to set values to a map which will expire and disappear after a specified time.

Here you can read the docs of this package, generated by godoc.org.

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Usage Example

package main

import (
	"log"
	"time"

	"github.com/zekroTJA/timedmap"
)

func main() {
	// Create a timed map with a cleanup timer interval of 1 second
	tm := timedmap.New(1 * time.Second)
	// Set value of key "hey" to 213, which will expire after 3 seconds
	tm.Set("hey", 213, 3*time.Second)
	// Print the value of "hey"
	printKeyVal(tm, "hey")
	// Block the main thread for 5 seconds
	// After this time, the key-value pair "hey": 213 has expired
	time.Sleep(5 * time.Second)
	// Now, this function should show that there is no key "hey"
	// in the map, because it has been expired
	printKeyVal(tm, "hey")
}

func printKeyVal(tm *timedmap.TimedMap, key interface{}) {
	d := tm.GetValue(key)
	if d == nil {
		log.Println("data expired")
		return
	}

	dInt := d.(int)
	log.Printf("%v = %d\n", key, dInt)
}

Further examples, you can find in the example directory.

---

Copyright (c) 2019 zekro Development (Ringo Hoffmann).
Covered by MIT licence.

Documentation

Index

• type TimedMap
  • func New(cleanupTickTime time.Duration) *TimedMap
  • func (tm *TimedMap) Contains(key interface{}) bool
  • func (tm *TimedMap) Flush()
  • func (tm *TimedMap) GetExpires(key interface{}) (time.Time, error)
  • func (tm *TimedMap) GetValue(key interface{}) interface{}
  • func (tm *TimedMap) Refresh(key interface{}, d time.Duration) error
  • func (tm *TimedMap) Remove(key interface{})
  • func (tm *TimedMap) Set(key, value interface{}, expiresAfter time.Duration, ...)
  • func (tm *TimedMap) Size() int
  • func (tm *TimedMap) StopCleaner()

Types

type TimedMap

type TimedMap struct {
	// contains filtered or unexported fields
}

TimedMap contains a map with all key-value pairs, and a timer, which cleans the map in the set tick durations from expired keys.

func New

func New(cleanupTickTime time.Duration) *TimedMap

New creates and returns a new instance of TimedMap. The passed cleanupTickTime will be passed to the cleanup Timer, which iterates through the map and deletes expired key-value pairs.

func (*TimedMap) Contains

func (tm *TimedMap) Contains(key interface{}) bool

Contains returns true, if the key exists in the map. false will be returned, if there is no value to the key or if the key-value pair was expired.

func (*TimedMap) Flush

func (tm *TimedMap) Flush()

Flush deletes all key-value pairs of the map.

func (*TimedMap) GetExpires

func (tm *TimedMap) GetExpires(key interface{}) (time.Time, error)

GetExpires returns the expire time of a key-value pair. If the key-value pair does not exist in the map or was expired, this will return an error object.

func (*TimedMap) GetValue

func (tm *TimedMap) GetValue(key interface{}) interface{}

GetValue returns an interface of the value of a key in the map. The returned value is nil if there is no value to the passed key or if the value was expired.

func (*TimedMap) Refresh

func (tm *TimedMap) Refresh(key interface{}, d time.Duration) error

Refresh extends the expire time for a key-value pair about the passed duration. If there is no value to the key passed, this will return an error object.

func (*TimedMap) Remove

func (tm *TimedMap) Remove(key interface{})

Remove deletes a key-value pair in the map.

func (*TimedMap) Set

func (tm *TimedMap) Set(key, value interface{}, expiresAfter time.Duration, cb ...func(value interface{}))

Set appends a key-value pair to the mao ir sets the value of a key. expiresAfter sets the expire time after the key-value pair will automatically be removed from the map.

func (*TimedMap) Size

func (tm *TimedMap) Size() int

Size returns the current number of key-value pairs existent in the map.

func (*TimedMap) StopCleaner

func (tm *TimedMap) StopCleaner()

StopCleaner stops the cleaner go routine and timer. This should always be called after exiting a scope where TimedMap is used that the data can be cleaned up correctly.