muesli / cache2go

Concurrency-safe Go caching library with expiration capabilities and access counters
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cache2go

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Concurrency-safe golang caching library with expiration capabilities.

Installation

Make sure you have a working Go environment (Go 1.2 or higher is required). See the install instructions.

To install cache2go, simply run:

go get github.com/muesli/cache2go

To compile it from source:

cd $GOPATH/src/github.com/muesli/cache2go
go get -u -v
go build && go test -v

Example

package main

import (
    "github.com/muesli/cache2go"
    "fmt"
    "time"
)

// Keys & values in cache2go can be of arbitrary types, e.g. a struct.
type myStruct struct {
    text     string
    moreData []byte
}

func main() {
    // Accessing a new cache table for the first time will create it.
    cache := cache2go.Cache("myCache")

    // We will put a new item in the cache. It will expire after
    // not being accessed via Value(key) for more than 5 seconds.
    val := myStruct{"This is a test!", []byte{}}
    cache.Add("someKey", 5*time.Second, &val)

    // Let's retrieve the item from the cache.
    res, err := cache.Value("someKey")
    if err == nil {
        fmt.Println("Found value in cache:", res.Data().(*myStruct).text)
    } else {
        fmt.Println("Error retrieving value from cache:", err)
    }

    // Wait for the item to expire in cache.
    time.Sleep(6 * time.Second)
    res, err = cache.Value("someKey")
    if err != nil {
        fmt.Println("Item is not cached (anymore).")
    }

    // Add another item that never expires.
    cache.Add("someKey", 0, &val)

    // cache2go supports a few handy callbacks and loading mechanisms.
    cache.SetAboutToDeleteItemCallback(func(e *cache2go.CacheItem) {
        fmt.Println("Deleting:", e.Key(), e.Data().(*myStruct).text, e.CreatedOn())
    })

    // Remove the item from the cache.
    cache.Delete("someKey")

    // And wipe the entire cache table.
    cache.Flush()
}

To run this example, go to examples/mycachedapp/ and run:

go run mycachedapp.go

You can find a few more examples here. Also see our test-cases in cache_test.go for further working examples.