Added README

This commit is contained in:
Patrick Mylund Nielsen 2012-01-02 14:13:36 +01:00
parent ca7e0d4f78
commit 741c94726a
2 changed files with 77 additions and 1 deletions

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README Normal file
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go-cache is an in-memory key:value store/cache similar to memcached that is suitable for
applications running on a single machine. Any object can be stored, for a given duration
or forever, and the cache can be used safely by multiple goroutines.
Installation:
goinstall github.com/pmylund/go-cache
Usage:
// Create a cache with a default expiration time of 5 minutes, and which purges
// expired items every 30 seconds
c := cache.New(5*time.Minute, 30*time.Second)
// Set the value of the key "foo" to "bar", with the default expiration time
c.Set("foo", "bar", 0)
// Set the value of the key "baz" to "yes", with no expiration time (the item
// won't be removed until it is re-set, or removed using c.Delete("baz")
c.Set("baz", "yes", -1)
// Get the string associated with the key "foo" from the cache
foo, found := c.Get("foo")
if found {
fmt.Println(foo)
}
// Since Go is statically typed, and cache values can be anything, type assertion
// is needed when values are being passed to functions that don't take arbitrary types,
// (i.e. interface{}). The simplest way to do this for values which will only be used
// once--e.g. for passing to another function--is:
foo, found := c.Get("foo")
if found {
MyFunction(foo.(string))
}
// This gets tedious if the value is used several times in the same function. You
// might do either of the following instead:
if x, found := c.Get("foo"); found {
foo := x.(string)
...
}
// or
var foo string
if x, found := c.Get("foo"); found {
foo = x.(string)
}
...
// foo can then be passed around freely as a string
// Want performance? Store pointers!
c.Set("foo", &MyStruct, 0)
if x, found := c.Get("foo"); found {
foo := x.(*MyStruct)
...
}
If you store a reference type like a pointer, slice, map or channel, you do not need to
run Set if you modify the underlying data. The cache does not serialize its data, so if
you modify a struct whose pointer you've stored in the cache, retrieving that pointer
with Get will point you to the same data:
foo := &MyStruct{Num: 1}
c.Set("foo", foo, 0)
...
x, _ := c.Get("foo")
foo := x.(MyStruct)
fmt.Println(foo.Num)
...
foo.Num++
...
x, _ := c.Get("foo")
foo := x.(MyStruct)
foo.Println(foo.Num)
will print:
1
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@ -8,7 +8,7 @@ import (
"time"
)
// Cache is an in-memory key:value store/cache similar to memcached that is suitable for
// go-cache is an in-memory key:value store/cache similar to memcached that is suitable for
// applications running on a single machine. Any object can be stored, for a given duration
// or forever, and the cache can be used safely by multiple goroutines.
//