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nexpie-grafana-theme
Commit 362162d6 by bergquist
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feat(mqe): add token cache

parent 69d63165
Showing with 1534 additions and 50 deletions
pkg/tsdb/mqe/model_parser.go
......@@ -6,14 +6,14 @@ import (
"github.com/grafana/grafana/pkg/tsdb"
)
func NewQueryParser() *MQEQueryParser {
return &MQEQueryParser{}
func NewQueryParser() *QueryParser {
return &QueryParser{}
}
type MQEQueryParser struct{}
type QueryParser struct{}
func (qp *MQEQueryParser) Parse(model *simplejson.Json, dsInfo *models.DataSource, queryContext *tsdb.QueryContext) (*MQEQuery, error) {
query := &MQEQuery{TimeRange: queryContext.TimeRange}
func (qp *QueryParser) Parse(model *simplejson.Json, dsInfo *models.DataSource, queryContext *tsdb.QueryContext) (*Query, error) {
query := &Query{TimeRange: queryContext.TimeRange}
query.AddAppToAlias = model.Get("addAppToAlias").MustBool(false)
query.AddHostToAlias = model.Get("addHostToAlias").MustBool(false)
query.UseRawQuery = model.Get("rawQuery").MustBool(false)
......@@ -22,11 +22,11 @@ func (qp *MQEQueryParser) Parse(model *simplejson.Json, dsInfo *models.DataSourc
query.Apps = model.Get("apps").MustStringArray([]string{})
query.Hosts = model.Get("hosts").MustStringArray([]string{})
var metrics []MQEMetric
var metrics []Metric
var err error
for _, metricsObj := range model.Get("metrics").MustArray() {
metricJson := simplejson.NewFromAny(metricsObj)
var m MQEMetric
var m Metric
m.Alias = metricJson.Get("alias").MustString("")
m.Metric, err = metricJson.Get("metric").String()
......
pkg/tsdb/mqe/model_parser_test.go
......@@ -11,7 +11,7 @@ import (
func TestMQEQueryParser(t *testing.T) {
Convey("MQE query parser", t, func() {
parser := &MQEQueryParser{}
parser := &QueryParser{}
dsInfo := &models.DataSource{JsonData: simplejson.New()}
queryContext := &tsdb.QueryContext{}
......
pkg/tsdb/mqe/mqe.go
......@@ -12,19 +12,20 @@ import (
"github.com/grafana/grafana/pkg/components/simplejson"
"github.com/grafana/grafana/pkg/log"
"github.com/grafana/grafana/pkg/models"
"github.com/grafana/grafana/pkg/setting"
"github.com/grafana/grafana/pkg/tsdb"
)
/*
TODO:
* response serie names with wildcards
* real caching
* performance. outgoing requests in pararell.
* frontend plugin. targetContainsTemplates
*/
type MQEExecutor struct {
*models.DataSource
queryParser *MQEQueryParser
responseParser *MQEResponseParser
queryParser *QueryParser
responseParser *ResponseParser
httpClient *http.Client
log log.Logger
tokenClient *TokenClient
......@@ -52,7 +53,7 @@ func init() {
type QueryToSend struct {
RawQuery string
QueryRef *MQEQuery
QueryRef *Query
}
func (e *MQEExecutor) Execute(ctx context.Context, queries tsdb.QuerySlice, queryContext *tsdb.QueryContext) *tsdb.BatchResult {
......@@ -63,7 +64,7 @@ func (e *MQEExecutor) Execute(ctx context.Context, queries tsdb.QuerySlice, quer
return result.WithError(err)
}
var mqeQueries []*MQEQuery
var mqeQueries []*Query
for _, v := range queries {
q, err := e.queryParser.Parse(v.Model, e.DataSource, queryContext)
if err != nil {
......@@ -82,9 +83,13 @@ func (e *MQEExecutor) Execute(ctx context.Context, queries tsdb.QuerySlice, quer
rawQueries = append(rawQueries, queries...)
}
e.log.Debug("Sending request", "url", e.DataSource.Url)
queryResult := &tsdb.QueryResult{}
for _, v := range rawQueries {
e.log.Info("Mqe executor", "query", v)
if setting.Env == setting.DEV {
e.log.Debug("Executing", "query", v)
}
req, err := e.createRequest(v.RawQuery)
......@@ -108,7 +113,11 @@ func (e *MQEExecutor) Execute(ctx context.Context, queries tsdb.QuerySlice, quer
}
func (e *MQEExecutor) createRequest(query string) (*http.Request, error) {
u, _ := url.Parse(e.Url)
u, err := url.Parse(e.Url)
if err != nil {
return nil, err
}
u.Path = path.Join(u.Path, "query")
payload := simplejson.New()
......@@ -131,6 +140,5 @@ func (e *MQEExecutor) createRequest(query string) (*http.Request, error) {
req.SetBasicAuth(e.BasicAuthUser, e.BasicAuthPassword)
}
e.log.Debug("Mqe request", "url", req.URL.String())
return req, nil
}
pkg/tsdb/mqe/response_parser.go
......@@ -13,8 +13,8 @@ import (
"github.com/grafana/grafana/pkg/tsdb"
)
func NewResponseParser() *MQEResponseParser {
return &MQEResponseParser{
func NewResponseParser() *ResponseParser {
return &ResponseParser{
log: log.New("tsdb.mqe"),
}
}
......@@ -44,11 +44,11 @@ type MQESerie struct {
Tagset map[string]string `json:"tagset"`
}
type MQEResponseParser struct {
type ResponseParser struct {
log log.Logger
}
func (parser *MQEResponseParser) Parse(res *http.Response, queryRef *MQEQuery) (*tsdb.QueryResult, error) {
func (parser *ResponseParser) Parse(res *http.Response, queryRef *Query) (*tsdb.QueryResult, error) {
body, err := ioutil.ReadAll(res.Body)
defer res.Body.Close()
if err != nil {
......@@ -63,12 +63,12 @@ func (parser *MQEResponseParser) Parse(res *http.Response, queryRef *MQEQuery) (
var data *MQEResponse = &MQEResponse{}
err = json.Unmarshal(body, data)
if err != nil {
parser.log.Info("Failed to unmarshal mqe response", "error", err, "status", res.Status, "body", string(body))
parser.log.Info("Failed to unmarshal response", "error", err, "status", res.Status, "body", string(body))
return nil, err
}
if !data.Success {
return nil, fmt.Errorf("MQE request failed.")
return nil, fmt.Errorf("Request failed.")
}
var series tsdb.TimeSeriesSlice
......
pkg/tsdb/mqe/response_parser_test.go
......@@ -20,7 +20,7 @@ func TestMQEResponseParser(t *testing.T) {
parser := NewResponseParser()
Convey("Can parse response", func() {
queryRef := &MQEQuery{
queryRef := &Query{
AddAppToAlias: true,
AddHostToAlias: true,
}
......
pkg/tsdb/mqe/token_client.go
......@@ -8,15 +8,25 @@ import (
"net/http"
"net/url"
"path"
"time"
"golang.org/x/net/context/ctxhttp"
"strconv"
"github.com/grafana/grafana/pkg/log"
"github.com/grafana/grafana/pkg/models"
"github.com/patrickmn/go-cache"
)
var tokenCache *cache.Cache
func init() {
tokenCache = cache.New(5*time.Minute, 30*time.Second)
}
type TokenClient struct {
tlog log.Logger
log log.Logger
Datasource *models.DataSource
HttpClient *http.Client
}
......@@ -25,27 +35,30 @@ func NewTokenClient(datasource *models.DataSource) *TokenClient {
httpClient, _ := datasource.GetHttpClient()
return &TokenClient{
tlog: log.New("tsdb.mqe.tokenclient"),
log: log.New("tsdb.mqe.tokenclient"),
Datasource: datasource,
HttpClient: httpClient,
}
}
var cache map[int64]*TokenBody = map[int64]*TokenBody{}
//Replace this stupid cache with internal cache from grafana master before merging
func (client *TokenClient) GetTokenData(ctx context.Context) (*TokenBody, error) {
_, excist := cache[client.Datasource.Id]
if !excist {
key := strconv.FormatInt(client.Datasource.Id, 10)
item, found := tokenCache.Get(key)
if found {
if result, ok := item.(*TokenBody); ok {
return result, nil
}
}
b, err := client.RequestTokenData(ctx)
if err != nil {
return nil, err
}
cache[client.Datasource.Id] = b
}
tokenCache.Set(key, b, cache.DefaultExpiration)
return cache[client.Datasource.Id], nil
return b, nil
}
func (client *TokenClient) RequestTokenData(ctx context.Context) (*TokenBody, error) {
......@@ -54,7 +67,7 @@ func (client *TokenClient) RequestTokenData(ctx context.Context) (*TokenBody, er
req, err := http.NewRequest(http.MethodGet, u.String(), nil)
if err != nil {
client.tlog.Info("Failed to create request", "error", err)
client.log.Info("Failed to create request", "error", err)
}
res, err := ctxhttp.Do(ctx, client.HttpClient, req)
......@@ -69,14 +82,14 @@ func (client *TokenClient) RequestTokenData(ctx context.Context) (*TokenBody, er
}
if res.StatusCode/100 != 2 {
client.tlog.Info("Request failed", "status", res.Status, "body", string(body))
client.log.Info("Request failed", "status", res.Status, "body", string(body))
return nil, fmt.Errorf("Request failed status: %v", res.Status)
}
var result *TokenResponse
err = json.Unmarshal(body, &result)
if err != nil {
client.tlog.Info("Failed to unmarshal graphite response", "error", err, "status", res.Status, "body", string(body))
client.log.Info("Failed to unmarshal response", "error", err, "status", res.Status, "body", string(body))
return nil, err
}
......
pkg/tsdb/mqe/types.go
......@@ -11,13 +11,13 @@ import (
"github.com/grafana/grafana/pkg/tsdb"
)
type MQEMetric struct {
type Metric struct {
Metric string
Alias string
}
type MQEQuery struct {
Metrics []MQEMetric
type Query struct {
Metrics []Metric
Hosts []string
Apps []string
AddAppToAlias bool
......@@ -32,7 +32,7 @@ var (
containsWildcardPattern *regexp.Regexp = regexp.MustCompile(`\*`)
)
func (q *MQEQuery) Build(availableSeries []string) ([]QueryToSend, error) {
func (q *Query) Build(availableSeries []string) ([]QueryToSend, error) {
var queriesToSend []QueryToSend
where := q.buildWhereClause()
......@@ -90,7 +90,7 @@ func (q *MQEQuery) Build(availableSeries []string) ([]QueryToSend, error) {
return queriesToSend, nil
}
func (q *MQEQuery) buildWhereClause() string {
func (q *Query) buildWhereClause() string {
hasApps := len(q.Apps) > 0
hasHosts := len(q.Hosts) > 0
......
pkg/tsdb/mqe/types_test.go
......@@ -25,11 +25,11 @@ func TestWildcardExpansion(t *testing.T) {
Convey("Can expanding query", t, func() {
Convey("Without wildcard series", func() {
query := &MQEQuery{
Metrics: []MQEMetric{
MQEMetric{Metric: "os.cpu.3.idle", Alias: ""},
MQEMetric{Metric: "os.cpu.2.idle", Alias: ""},
MQEMetric{Metric: "os.cpu.1.idle", Alias: "cpu"},
query := &Query{
Metrics: []Metric{
Metric{Metric: "os.cpu.3.idle", Alias: ""},
Metric{Metric: "os.cpu.2.idle", Alias: ""},
Metric{Metric: "os.cpu.1.idle", Alias: "cpu"},
},
Hosts: []string{"staples-lab-1", "staples-lab-2"},
Apps: []string{"demoapp-1", "demoapp-2"},
......@@ -47,9 +47,9 @@ func TestWildcardExpansion(t *testing.T) {
})
Convey("Containg wildcard series", func() {
query := &MQEQuery{
Metrics: []MQEMetric{
MQEMetric{Metric: "os.cpu*", Alias: ""},
query := &Query{
Metrics: []Metric{
Metric{Metric: "os.cpu*", Alias: ""},
},
Hosts: []string{"staples-lab-1"},
AddAppToAlias: false,
......
vendor/github.com/patrickmn/go-cache/CONTRIBUTORS 0 → 100644
This is a list of people who have contributed code to go-cache. They, or their
employers, are the copyright holders of the contributed code. Contributed code
is subject to the license restrictions listed in LICENSE (as they were when the
code was contributed.)
Dustin Sallings <dustin@spy.net>
Jason Mooberry <jasonmoo@me.com>
Sergey Shepelev <temotor@gmail.com>
vendor/github.com/patrickmn/go-cache/LICENSE 0 → 100644
Copyright (c) 2012-2016 Patrick Mylund Nielsen and the go-cache contributors
Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
vendor/github.com/patrickmn/go-cache/README.md 0 → 100644
# go-cache
go-cache is an in-memory key:value store/cache similar to memcached that is
suitable for applications running on a single machine. Its major advantage is
that, being essentially a thread-safe `map[string]interface{}` with expiration
times, it doesn't need to serialize or transmit its contents over the network.
Any object can be stored, for a given duration or forever, and the cache can be
safely used by multiple goroutines.
Although go-cache isn't meant to be used as a persistent datastore, the entire
cache can be saved to and loaded from a file (using `c.Items()` to retrieve the
items map to serialize, and `NewFrom()` to create a cache from a deserialized
one) to recover from downtime quickly. (See the docs for `NewFrom()` for caveats.)
### Installation
`go get github.com/patrickmn/go-cache`
### Usage
```go
import (
"fmt"
"github.com/patrickmn/go-cache"
"time"
)
func main() {
// 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", cache.DefaultExpiration)
// Set the value of the key "baz" to 42, with no expiration time
// (the item won't be removed until it is re-set, or removed using
// c.Delete("baz")
c.Set("baz", 42, cache.NoExpiration)
// 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, cache.DefaultExpiration)
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 cached
// reference points to the same memory, 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, cache.DefaultExpiration)
// ...
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
// 2
}
```
### Reference
`godoc` or [http://godoc.org/github.com/patrickmn/go-cache](http://godoc.org/github.com/patrickmn/go-cache)
vendor/github.com/patrickmn/go-cache/cache.go 0 → 100644
package cache
import (
"encoding/gob"
"fmt"
"io"
"os"
"runtime"
"sync"
"time"
)
type Item struct {
Object interface{}
Expiration int64
}
// Returns true if the item has expired.
func (item Item) Expired() bool {
if item.Expiration == 0 {
return false
}
return time.Now().UnixNano() > item.Expiration
}
const (
// For use with functions that take an expiration time.
NoExpiration time.Duration = -1
// For use with functions that take an expiration time. Equivalent to
// passing in the same expiration duration as was given to New() or
// NewFrom() when the cache was created (e.g. 5 minutes.)
DefaultExpiration time.Duration = 0
)
type Cache struct {
*cache
// If this is confusing, see the comment at the bottom of New()
}
type cache struct {
defaultExpiration time.Duration
items map[string]Item
mu sync.RWMutex
onEvicted func(string, interface{})
janitor *janitor
}
// Add an item to the cache, replacing any existing item. If the duration is 0
// (DefaultExpiration), the cache's default expiration time is used. If it is -1
// (NoExpiration), the item never expires.
func (c *cache) Set(k string, x interface{}, d time.Duration) {
// "Inlining" of set
var e int64
if d == DefaultExpiration {
d = c.defaultExpiration
}
if d > 0 {
e = time.Now().Add(d).UnixNano()
}
c.mu.Lock()
c.items[k] = Item{
Object: x,
Expiration: e,
}
// TODO: Calls to mu.Unlock are currently not deferred because defer
// adds ~200 ns (as of go1.)
c.mu.Unlock()
}
func (c *cache) set(k string, x interface{}, d time.Duration) {
var e int64
if d == DefaultExpiration {
d = c.defaultExpiration
}
if d > 0 {
e = time.Now().Add(d).UnixNano()
}
c.items[k] = Item{
Object: x,
Expiration: e,
}
}
// Add an item to the cache, replacing any existing item, using the default
// expiration.
func (c *cache) SetDefault(k string, x interface{}) {
c.Set(k, x, DefaultExpiration)
}
// Add an item to the cache only if an item doesn't already exist for the given
// key, or if the existing item has expired. Returns an error otherwise.
func (c *cache) Add(k string, x interface{}, d time.Duration) error {
c.mu.Lock()
_, found := c.get(k)
if found {
c.mu.Unlock()
return fmt.Errorf("Item %s already exists", k)
}
c.set(k, x, d)
c.mu.Unlock()
return nil
}
// Set a new value for the cache key only if it already exists, and the existing
// item hasn't expired. Returns an error otherwise.
func (c *cache) Replace(k string, x interface{}, d time.Duration) error {
c.mu.Lock()
_, found := c.get(k)
if !found {
c.mu.Unlock()
return fmt.Errorf("Item %s doesn't exist", k)
}
c.set(k, x, d)
c.mu.Unlock()
return nil
}
// Get an item from the cache. Returns the item or nil, and a bool indicating
// whether the key was found.
func (c *cache) Get(k string) (interface{}, bool) {
c.mu.RLock()
// "Inlining" of get and Expired
item, found := c.items[k]
if !found {
c.mu.RUnlock()
return nil, false
}
if item.Expiration > 0 {
if time.Now().UnixNano() > item.Expiration {
c.mu.RUnlock()
return nil, false
}
}
c.mu.RUnlock()
return item.Object, true
}
func (c *cache) get(k string) (interface{}, bool) {
item, found := c.items[k]
if !found {
return nil, false
}
// "Inlining" of Expired
if item.Expiration > 0 {
if time.Now().UnixNano() > item.Expiration {
return nil, false
}
}
return item.Object, true
}
// Increment an item of type int, int8, int16, int32, int64, uintptr, uint,
// uint8, uint32, or uint64, float32 or float64 by n. Returns an error if the
// item's value is not an integer, if it was not found, or if it is not
// possible to increment it by n. To retrieve the incremented value, use one
// of the specialized methods, e.g. IncrementInt64.
func (c *cache) Increment(k string, n int64) error {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return fmt.Errorf("Item %s not found", k)
}
switch v.Object.(type) {
case int:
v.Object = v.Object.(int) + int(n)
case int8:
v.Object = v.Object.(int8) + int8(n)
case int16:
v.Object = v.Object.(int16) + int16(n)
case int32:
v.Object = v.Object.(int32) + int32(n)
case int64:
v.Object = v.Object.(int64) + n
case uint:
v.Object = v.Object.(uint) + uint(n)
case uintptr:
v.Object = v.Object.(uintptr) + uintptr(n)
case uint8:
v.Object = v.Object.(uint8) + uint8(n)
case uint16:
v.Object = v.Object.(uint16) + uint16(n)
case uint32:
v.Object = v.Object.(uint32) + uint32(n)
case uint64:
v.Object = v.Object.(uint64) + uint64(n)
case float32:
v.Object = v.Object.(float32) + float32(n)
case float64:
v.Object = v.Object.(float64) + float64(n)
default:
c.mu.Unlock()
return fmt.Errorf("The value for %s is not an integer", k)
}
c.items[k] = v
c.mu.Unlock()
return nil
}
// Increment an item of type float32 or float64 by n. Returns an error if the
// item's value is not floating point, if it was not found, or if it is not
// possible to increment it by n. Pass a negative number to decrement the
// value. To retrieve the incremented value, use one of the specialized methods,
// e.g. IncrementFloat64.
func (c *cache) IncrementFloat(k string, n float64) error {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return fmt.Errorf("Item %s not found", k)
}
switch v.Object.(type) {
case float32:
v.Object = v.Object.(float32) + float32(n)
case float64:
v.Object = v.Object.(float64) + n
default:
c.mu.Unlock()
return fmt.Errorf("The value for %s does not have type float32 or float64", k)
}
c.items[k] = v
c.mu.Unlock()
return nil
}
// Increment an item of type int by n. Returns an error if the item's value is
// not an int, or if it was not found. If there is no error, the incremented
// value is returned.
func (c *cache) IncrementInt(k string, n int) (int, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(int)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an int", k)
}
nv := rv + n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Increment an item of type int8 by n. Returns an error if the item's value is
// not an int8, or if it was not found. If there is no error, the incremented
// value is returned.
func (c *cache) IncrementInt8(k string, n int8) (int8, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(int8)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an int8", k)
}
nv := rv + n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Increment an item of type int16 by n. Returns an error if the item's value is
// not an int16, or if it was not found. If there is no error, the incremented
// value is returned.
func (c *cache) IncrementInt16(k string, n int16) (int16, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(int16)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an int16", k)
}
nv := rv + n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Increment an item of type int32 by n. Returns an error if the item's value is
// not an int32, or if it was not found. If there is no error, the incremented
// value is returned.
func (c *cache) IncrementInt32(k string, n int32) (int32, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(int32)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an int32", k)
}
nv := rv + n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Increment an item of type int64 by n. Returns an error if the item's value is
// not an int64, or if it was not found. If there is no error, the incremented
// value is returned.
func (c *cache) IncrementInt64(k string, n int64) (int64, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(int64)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an int64", k)
}
nv := rv + n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Increment an item of type uint by n. Returns an error if the item's value is
// not an uint, or if it was not found. If there is no error, the incremented
// value is returned.
func (c *cache) IncrementUint(k string, n uint) (uint, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(uint)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an uint", k)
}
nv := rv + n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Increment an item of type uintptr by n. Returns an error if the item's value
// is not an uintptr, or if it was not found. If there is no error, the
// incremented value is returned.
func (c *cache) IncrementUintptr(k string, n uintptr) (uintptr, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(uintptr)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an uintptr", k)
}
nv := rv + n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Increment an item of type uint8 by n. Returns an error if the item's value
// is not an uint8, or if it was not found. If there is no error, the
// incremented value is returned.
func (c *cache) IncrementUint8(k string, n uint8) (uint8, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(uint8)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an uint8", k)
}
nv := rv + n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Increment an item of type uint16 by n. Returns an error if the item's value
// is not an uint16, or if it was not found. If there is no error, the
// incremented value is returned.
func (c *cache) IncrementUint16(k string, n uint16) (uint16, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(uint16)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an uint16", k)
}
nv := rv + n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Increment an item of type uint32 by n. Returns an error if the item's value
// is not an uint32, or if it was not found. If there is no error, the
// incremented value is returned.
func (c *cache) IncrementUint32(k string, n uint32) (uint32, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(uint32)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an uint32", k)
}
nv := rv + n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Increment an item of type uint64 by n. Returns an error if the item's value
// is not an uint64, or if it was not found. If there is no error, the
// incremented value is returned.
func (c *cache) IncrementUint64(k string, n uint64) (uint64, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(uint64)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an uint64", k)
}
nv := rv + n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Increment an item of type float32 by n. Returns an error if the item's value
// is not an float32, or if it was not found. If there is no error, the
// incremented value is returned.
func (c *cache) IncrementFloat32(k string, n float32) (float32, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(float32)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an float32", k)
}
nv := rv + n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Increment an item of type float64 by n. Returns an error if the item's value
// is not an float64, or if it was not found. If there is no error, the
// incremented value is returned.
func (c *cache) IncrementFloat64(k string, n float64) (float64, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(float64)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an float64", k)
}
nv := rv + n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Decrement an item of type int, int8, int16, int32, int64, uintptr, uint,
// uint8, uint32, or uint64, float32 or float64 by n. Returns an error if the
// item's value is not an integer, if it was not found, or if it is not
// possible to decrement it by n. To retrieve the decremented value, use one
// of the specialized methods, e.g. DecrementInt64.
func (c *cache) Decrement(k string, n int64) error {
// TODO: Implement Increment and Decrement more cleanly.
// (Cannot do Increment(k, n*-1) for uints.)
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return fmt.Errorf("Item not found")
}
switch v.Object.(type) {
case int:
v.Object = v.Object.(int) - int(n)
case int8:
v.Object = v.Object.(int8) - int8(n)
case int16:
v.Object = v.Object.(int16) - int16(n)
case int32:
v.Object = v.Object.(int32) - int32(n)
case int64:
v.Object = v.Object.(int64) - n
case uint:
v.Object = v.Object.(uint) - uint(n)
case uintptr:
v.Object = v.Object.(uintptr) - uintptr(n)
case uint8:
v.Object = v.Object.(uint8) - uint8(n)
case uint16:
v.Object = v.Object.(uint16) - uint16(n)
case uint32:
v.Object = v.Object.(uint32) - uint32(n)
case uint64:
v.Object = v.Object.(uint64) - uint64(n)
case float32:
v.Object = v.Object.(float32) - float32(n)
case float64:
v.Object = v.Object.(float64) - float64(n)
default:
c.mu.Unlock()
return fmt.Errorf("The value for %s is not an integer", k)
}
c.items[k] = v
c.mu.Unlock()
return nil
}
// Decrement an item of type float32 or float64 by n. Returns an error if the
// item's value is not floating point, if it was not found, or if it is not
// possible to decrement it by n. Pass a negative number to decrement the
// value. To retrieve the decremented value, use one of the specialized methods,
// e.g. DecrementFloat64.
func (c *cache) DecrementFloat(k string, n float64) error {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return fmt.Errorf("Item %s not found", k)
}
switch v.Object.(type) {
case float32:
v.Object = v.Object.(float32) - float32(n)
case float64:
v.Object = v.Object.(float64) - n
default:
c.mu.Unlock()
return fmt.Errorf("The value for %s does not have type float32 or float64", k)
}
c.items[k] = v
c.mu.Unlock()
return nil
}
// Decrement an item of type int by n. Returns an error if the item's value is
// not an int, or if it was not found. If there is no error, the decremented
// value is returned.
func (c *cache) DecrementInt(k string, n int) (int, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(int)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an int", k)
}
nv := rv - n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Decrement an item of type int8 by n. Returns an error if the item's value is
// not an int8, or if it was not found. If there is no error, the decremented
// value is returned.
func (c *cache) DecrementInt8(k string, n int8) (int8, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(int8)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an int8", k)
}
nv := rv - n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Decrement an item of type int16 by n. Returns an error if the item's value is
// not an int16, or if it was not found. If there is no error, the decremented
// value is returned.
func (c *cache) DecrementInt16(k string, n int16) (int16, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(int16)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an int16", k)
}
nv := rv - n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Decrement an item of type int32 by n. Returns an error if the item's value is
// not an int32, or if it was not found. If there is no error, the decremented
// value is returned.
func (c *cache) DecrementInt32(k string, n int32) (int32, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(int32)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an int32", k)
}
nv := rv - n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Decrement an item of type int64 by n. Returns an error if the item's value is
// not an int64, or if it was not found. If there is no error, the decremented
// value is returned.
func (c *cache) DecrementInt64(k string, n int64) (int64, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(int64)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an int64", k)
}
nv := rv - n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Decrement an item of type uint by n. Returns an error if the item's value is
// not an uint, or if it was not found. If there is no error, the decremented
// value is returned.
func (c *cache) DecrementUint(k string, n uint) (uint, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(uint)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an uint", k)
}
nv := rv - n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Decrement an item of type uintptr by n. Returns an error if the item's value
// is not an uintptr, or if it was not found. If there is no error, the
// decremented value is returned.
func (c *cache) DecrementUintptr(k string, n uintptr) (uintptr, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(uintptr)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an uintptr", k)
}
nv := rv - n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Decrement an item of type uint8 by n. Returns an error if the item's value is
// not an uint8, or if it was not found. If there is no error, the decremented
// value is returned.
func (c *cache) DecrementUint8(k string, n uint8) (uint8, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(uint8)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an uint8", k)
}
nv := rv - n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Decrement an item of type uint16 by n. Returns an error if the item's value
// is not an uint16, or if it was not found. If there is no error, the
// decremented value is returned.
func (c *cache) DecrementUint16(k string, n uint16) (uint16, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(uint16)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an uint16", k)
}
nv := rv - n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Decrement an item of type uint32 by n. Returns an error if the item's value
// is not an uint32, or if it was not found. If there is no error, the
// decremented value is returned.
func (c *cache) DecrementUint32(k string, n uint32) (uint32, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(uint32)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an uint32", k)
}
nv := rv - n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Decrement an item of type uint64 by n. Returns an error if the item's value
// is not an uint64, or if it was not found. If there is no error, the
// decremented value is returned.
func (c *cache) DecrementUint64(k string, n uint64) (uint64, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(uint64)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an uint64", k)
}
nv := rv - n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Decrement an item of type float32 by n. Returns an error if the item's value
// is not an float32, or if it was not found. If there is no error, the
// decremented value is returned.
func (c *cache) DecrementFloat32(k string, n float32) (float32, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(float32)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an float32", k)
}
nv := rv - n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Decrement an item of type float64 by n. Returns an error if the item's value
// is not an float64, or if it was not found. If there is no error, the
// decremented value is returned.
func (c *cache) DecrementFloat64(k string, n float64) (float64, error) {
c.mu.Lock()
v, found := c.items[k]
if !found || v.Expired() {
c.mu.Unlock()
return 0, fmt.Errorf("Item %s not found", k)
}
rv, ok := v.Object.(float64)
if !ok {
c.mu.Unlock()
return 0, fmt.Errorf("The value for %s is not an float64", k)
}
nv := rv - n
v.Object = nv
c.items[k] = v
c.mu.Unlock()
return nv, nil
}
// Delete an item from the cache. Does nothing if the key is not in the cache.
func (c *cache) Delete(k string) {
c.mu.Lock()
v, evicted := c.delete(k)
c.mu.Unlock()
if evicted {
c.onEvicted(k, v)
}
}
func (c *cache) delete(k string) (interface{}, bool) {
if c.onEvicted != nil {
if v, found := c.items[k]; found {
delete(c.items, k)
return v.Object, true
}
}
delete(c.items, k)
return nil, false
}
type keyAndValue struct {
key string
value interface{}
}
// Delete all expired items from the cache.
func (c *cache) DeleteExpired() {
var evictedItems []keyAndValue
now := time.Now().UnixNano()
c.mu.Lock()
for k, v := range c.items {
// "Inlining" of expired
if v.Expiration > 0 && now > v.Expiration {
ov, evicted := c.delete(k)
if evicted {
evictedItems = append(evictedItems, keyAndValue{k, ov})
}
}
}
c.mu.Unlock()
for _, v := range evictedItems {
c.onEvicted(v.key, v.value)
}
}
// Sets an (optional) function that is called with the key and value when an
// item is evicted from the cache. (Including when it is deleted manually, but
// not when it is overwritten.) Set to nil to disable.
func (c *cache) OnEvicted(f func(string, interface{})) {
c.mu.Lock()
c.onEvicted = f
c.mu.Unlock()
}
// Write the cache's items (using Gob) to an io.Writer.
//
// NOTE: This method is deprecated in favor of c.Items() and NewFrom() (see the
// documentation for NewFrom().)
func (c *cache) Save(w io.Writer) (err error) {
enc := gob.NewEncoder(w)
defer func() {
if x := recover(); x != nil {
err = fmt.Errorf("Error registering item types with Gob library")
}
}()
c.mu.RLock()
defer c.mu.RUnlock()
for _, v := range c.items {
gob.Register(v.Object)
}
err = enc.Encode(&c.items)
return
}
// Save the cache's items to the given filename, creating the file if it
// doesn't exist, and overwriting it if it does.
//
// NOTE: This method is deprecated in favor of c.Items() and NewFrom() (see the
// documentation for NewFrom().)
func (c *cache) SaveFile(fname string) error {
fp, err := os.Create(fname)
if err != nil {
return err
}
err = c.Save(fp)
if err != nil {
fp.Close()
return err
}
return fp.Close()
}
// Add (Gob-serialized) cache items from an io.Reader, excluding any items with
// keys that already exist (and haven't expired) in the current cache.
//
// NOTE: This method is deprecated in favor of c.Items() and NewFrom() (see the
// documentation for NewFrom().)
func (c *cache) Load(r io.Reader) error {
dec := gob.NewDecoder(r)
items := map[string]Item{}
err := dec.Decode(&items)
if err == nil {
c.mu.Lock()
defer c.mu.Unlock()
for k, v := range items {
ov, found := c.items[k]
if !found || ov.Expired() {
c.items[k] = v
}
}
}
return err
}
// Load and add cache items from the given filename, excluding any items with
// keys that already exist in the current cache.
//
// NOTE: This method is deprecated in favor of c.Items() and NewFrom() (see the
// documentation for NewFrom().)
func (c *cache) LoadFile(fname string) error {
fp, err := os.Open(fname)
if err != nil {
return err
}
err = c.Load(fp)
if err != nil {
fp.Close()
return err
}
return fp.Close()
}
// Copies all unexpired items in the cache into a new map and returns it.
func (c *cache) Items() map[string]Item {
c.mu.RLock()
defer c.mu.RUnlock()
m := make(map[string]Item, len(c.items))
now := time.Now().UnixNano()
for k, v := range c.items {
// "Inlining" of Expired
if v.Expiration > 0 {
if now > v.Expiration {
continue
}
}
m[k] = v
}
return m
}
// Returns the number of items in the cache. This may include items that have
// expired, but have not yet been cleaned up.
func (c *cache) ItemCount() int {
c.mu.RLock()
n := len(c.items)
c.mu.RUnlock()
return n
}
// Delete all items from the cache.
func (c *cache) Flush() {
c.mu.Lock()
c.items = map[string]Item{}
c.mu.Unlock()
}
type janitor struct {
Interval time.Duration
stop chan bool
}
func (j *janitor) Run(c *cache) {
j.stop = make(chan bool)
ticker := time.NewTicker(j.Interval)
for {
select {
case <-ticker.C:
c.DeleteExpired()
case <-j.stop:
ticker.Stop()
return
}
}
}
func stopJanitor(c *Cache) {
c.janitor.stop <- true
}
func runJanitor(c *cache, ci time.Duration) {
j := &janitor{
Interval: ci,
}
c.janitor = j
go j.Run(c)
}
func newCache(de time.Duration, m map[string]Item) *cache {
if de == 0 {
de = -1
}
c := &cache{
defaultExpiration: de,
items: m,
}
return c
}
func newCacheWithJanitor(de time.Duration, ci time.Duration, m map[string]Item) *Cache {
c := newCache(de, m)
// This trick ensures that the janitor goroutine (which--granted it
// was enabled--is running DeleteExpired on c forever) does not keep
// the returned C object from being garbage collected. When it is
// garbage collected, the finalizer stops the janitor goroutine, after
// which c can be collected.
C := &Cache{c}
if ci > 0 {
runJanitor(c, ci)
runtime.SetFinalizer(C, stopJanitor)
}
return C
}
// Return a new cache with a given default expiration duration and cleanup
// interval. If the expiration duration is less than one (or NoExpiration),
// the items in the cache never expire (by default), and must be deleted
// manually. If the cleanup interval is less than one, expired items are not
// deleted from the cache before calling c.DeleteExpired().
func New(defaultExpiration, cleanupInterval time.Duration) *Cache {
items := make(map[string]Item)
return newCacheWithJanitor(defaultExpiration, cleanupInterval, items)
}
// Return a new cache with a given default expiration duration and cleanup
// interval. If the expiration duration is less than one (or NoExpiration),
// the items in the cache never expire (by default), and must be deleted
// manually. If the cleanup interval is less than one, expired items are not
// deleted from the cache before calling c.DeleteExpired().
//
// NewFrom() also accepts an items map which will serve as the underlying map
// for the cache. This is useful for starting from a deserialized cache
// (serialized using e.g. gob.Encode() on c.Items()), or passing in e.g.
// make(map[string]Item, 500) to improve startup performance when the cache
// is expected to reach a certain minimum size.
//
// Only the cache's methods synchronize access to this map, so it is not
// recommended to keep any references to the map around after creating a cache.
// If need be, the map can be accessed at a later point using c.Items() (subject
// to the same caveat.)
//
// Note regarding serialization: When using e.g. gob, make sure to
// gob.Register() the individual types stored in the cache before encoding a
// map retrieved with c.Items(), and to register those same types before
// decoding a blob containing an items map.
func NewFrom(defaultExpiration, cleanupInterval time.Duration, items map[string]Item) *Cache {
return newCacheWithJanitor(defaultExpiration, cleanupInterval, items)
}
vendor/github.com/patrickmn/go-cache/sharded.go 0 → 100644
package cache
import (
"crypto/rand"
"math"
"math/big"
insecurerand "math/rand"
"os"
"runtime"
"time"
)
// This is an experimental and unexported (for now) attempt at making a cache
// with better algorithmic complexity than the standard one, namely by
// preventing write locks of the entire cache when an item is added. As of the
// time of writing, the overhead of selecting buckets results in cache
// operations being about twice as slow as for the standard cache with small
// total cache sizes, and faster for larger ones.
//
// See cache_test.go for a few benchmarks.
type unexportedShardedCache struct {
*shardedCache
}
type shardedCache struct {
seed uint32
m uint32
cs []*cache
janitor *shardedJanitor
}
// djb2 with better shuffling. 5x faster than FNV with the hash.Hash overhead.
func djb33(seed uint32, k string) uint32 {
var (
l = uint32(len(k))
d = 5381 + seed + l
i = uint32(0)
)
// Why is all this 5x faster than a for loop?
if l >= 4 {
for i < l-4 {
d = (d * 33) ^ uint32(k[i])
d = (d * 33) ^ uint32(k[i+1])
d = (d * 33) ^ uint32(k[i+2])
d = (d * 33) ^ uint32(k[i+3])
i += 4
}
}
switch l - i {
case 1:
case 2:
d = (d * 33) ^ uint32(k[i])
case 3:
d = (d * 33) ^ uint32(k[i])
d = (d * 33) ^ uint32(k[i+1])
case 4:
d = (d * 33) ^ uint32(k[i])
d = (d * 33) ^ uint32(k[i+1])
d = (d * 33) ^ uint32(k[i+2])
}
return d ^ (d >> 16)
}
func (sc *shardedCache) bucket(k string) *cache {
return sc.cs[djb33(sc.seed, k)%sc.m]
}
func (sc *shardedCache) Set(k string, x interface{}, d time.Duration) {
sc.bucket(k).Set(k, x, d)
}
func (sc *shardedCache) Add(k string, x interface{}, d time.Duration) error {
return sc.bucket(k).Add(k, x, d)
}
func (sc *shardedCache) Replace(k string, x interface{}, d time.Duration) error {
return sc.bucket(k).Replace(k, x, d)
}
func (sc *shardedCache) Get(k string) (interface{}, bool) {
return sc.bucket(k).Get(k)
}
func (sc *shardedCache) Increment(k string, n int64) error {
return sc.bucket(k).Increment(k, n)
}
func (sc *shardedCache) IncrementFloat(k string, n float64) error {
return sc.bucket(k).IncrementFloat(k, n)
}
func (sc *shardedCache) Decrement(k string, n int64) error {
return sc.bucket(k).Decrement(k, n)
}
func (sc *shardedCache) Delete(k string) {
sc.bucket(k).Delete(k)
}
func (sc *shardedCache) DeleteExpired() {
for _, v := range sc.cs {
v.DeleteExpired()
}
}
// Returns the items in the cache. This may include items that have expired,
// but have not yet been cleaned up. If this is significant, the Expiration
// fields of the items should be checked. Note that explicit synchronization
// is needed to use a cache and its corresponding Items() return values at
// the same time, as the maps are shared.
func (sc *shardedCache) Items() []map[string]Item {
res := make([]map[string]Item, len(sc.cs))
for i, v := range sc.cs {
res[i] = v.Items()
}
return res
}
func (sc *shardedCache) Flush() {
for _, v := range sc.cs {
v.Flush()
}
}
type shardedJanitor struct {
Interval time.Duration
stop chan bool
}
func (j *shardedJanitor) Run(sc *shardedCache) {
j.stop = make(chan bool)
tick := time.Tick(j.Interval)
for {
select {
case <-tick:
sc.DeleteExpired()
case <-j.stop:
return
}
}
}
func stopShardedJanitor(sc *unexportedShardedCache) {
sc.janitor.stop <- true
}
func runShardedJanitor(sc *shardedCache, ci time.Duration) {
j := &shardedJanitor{
Interval: ci,
}
sc.janitor = j
go j.Run(sc)
}
func newShardedCache(n int, de time.Duration) *shardedCache {
max := big.NewInt(0).SetUint64(uint64(math.MaxUint32))
rnd, err := rand.Int(rand.Reader, max)
var seed uint32
if err != nil {
os.Stderr.Write([]byte("WARNING: go-cache's newShardedCache failed to read from the system CSPRNG (/dev/urandom or equivalent.) Your system's security may be compromised. Continuing with an insecure seed.\n"))
seed = insecurerand.Uint32()
} else {
seed = uint32(rnd.Uint64())
}
sc := &shardedCache{
seed: seed,
m: uint32(n),
cs: make([]*cache, n),
}
for i := 0; i < n; i++ {
c := &cache{
defaultExpiration: de,
items: map[string]Item{},
}
sc.cs[i] = c
}
return sc
}
func unexportedNewSharded(defaultExpiration, cleanupInterval time.Duration, shards int) *unexportedShardedCache {
if defaultExpiration == 0 {
defaultExpiration = -1
}
sc := newShardedCache(shards, defaultExpiration)
SC := &unexportedShardedCache{sc}
if cleanupInterval > 0 {
runShardedJanitor(sc, cleanupInterval)
runtime.SetFinalizer(SC, stopShardedJanitor)
}
return SC
}
vendor/vendor.json
......@@ -315,6 +315,12 @@
"versionExact": "v1.21.1"
},
{
"checksumSHA1": "8z32QKTSDusa4QQyunKE4kyYXZ8=",
"path": "github.com/patrickmn/go-cache",
"revision": "e7a9def80f35fe1b170b7b8b68871d59dea117e1",
"revisionTime": "2016-11-25T23:48:19Z"
},
{
"checksumSHA1": "SMUvX2B8eoFd9wnPofwBKlN6btE=",
"path": "github.com/prometheus/client_golang/api/prometheus",
"revision": "5636dc67ae776adf5590da7349e70fbb9559972d",
......
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