Merge branch 'master' of https://github.com/godruoyi/go-snowflake

fix: small typo

.github/FUNDING.yml

@@ -0,0 +1,2 @@
+# These are supported funding model platforms
+custom: ["https://images.godruoyi.com/wechat.png"]

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2021 Godruoyi
+
+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.

example/example.go

@@ -2,13 +2,18 @@ package main
 
 import (
 	"fmt"
+	"time"
 
 	"github.com/godruoyi/go-snowflake"
 )
 
 func main() {
+	// set starttime and machineID for the first time if you wan't to use the default value
+	snowflake.SetStartTime(time.Date(2021, 9, 1, 0, 0, 0, 0, time.UTC))
+	snowflake.SetMachineID(snowflake.PrivateIPToMachineID()) // testing, not to be used in production
+
 	id := snowflake.ID()
-	fmt.Println(id)
+	fmt.Println(id) // 1537200202186752
 
 	sid := snowflake.ParseID(id)
 	// SID {

readme.md

@@ -36,7 +36,7 @@ So if you want use the snowflake algorithm to generate unique ID, You must ensur
 
 Based on this, we created this package and integrated multiple sequence-number providers into it.
 
-* AtomicResolver (base sync/atmoic)
+* AtomicResolver (base sync/atomic)
 
 > Each provider only needs to ensure that the serial number generated in the same millisecond is different. You can get a unique ID.
 
@@ -54,7 +54,7 @@ Based on this, we created this package and integrated multiple sequence-number p
 $ go get github.com/godruoyi/go-snowflake
 ```
 
-## Useage
+## Usage
 
 1. simple to use.
 

snowflake.go

@@ -61,12 +61,12 @@ func NextID() (uint64, error) {
 		}
 	}
 
-	df := int(elapsedTime(startTime))
+	df := int(elapsedTime(c, startTime))
 	if df < 0 || df > MaxTimestamp {
 		return 0, errors.New("The maximum life cycle of the snowflake algorithm is 2^41-1(millis), please check starttime")
 	}
 
-	id := uint64(df<<timestampMoveLength | machineID<<machineIDMoveLength | int(seq))
+	id := uint64((df << timestampMoveLength) | (machineID << machineIDMoveLength) | int(seq))
 	return id, nil
 }
 
@@ -84,12 +84,12 @@ func SetStartTime(s time.Time) {
 		panic("The start time cannot be a zero value")
 	}
 
-	if s.After(time.Now()) {
+	if s.After(time.Now().UTC()) {
 		panic("The s cannot be greater than the current millisecond")
 	}
 
 	// Because s must after now, so the `df` not < 0.
-	df := elapsedTime(s)
+	df := elapsedTime(currentMillis(), s)
 	if df > MaxTimestamp {
 		panic("The maximum life cycle of the snowflake algorithm is 69 years")
 	}
@@ -163,8 +163,8 @@ func callSequenceResolver() SequenceResolver {
 	return resolver
 }
 
-func elapsedTime(s time.Time) int64 {
-	return currentMillis() - s.UTC().UnixNano()/1e6
+func elapsedTime(nowms int64, s time.Time) int64 {
+	return nowms - s.UTC().UnixNano()/1e6
 }
 
 // currentMillis get current millisecond.

snowflake_test.go

@@ -2,6 +2,7 @@ package snowflake_test
 
 import (
 	"errors"
+	"sync"
 	"testing"
 	"time"
 
@@ -14,6 +15,48 @@ func TestID(t *testing.T) {
 	if id <= 0 {
 		t.Error("The snowflake should't < 0.")
 	}
+
+	mp := make(map[uint64]bool)
+	for i := 0; i < 100000; i++ {
+		id, e := snowflake.NextID()
+		if e != nil {
+			t.Error(e)
+			continue
+		}
+		if _, ok := mp[id]; ok {
+			t.Error("ID should't repeat", id)
+			break
+		}
+		mp[id] = true
+	}
+}
+
+func TestID_bitch(t *testing.T) {
+	le := 100000
+	ch := make(chan uint64, le)
+	var wg sync.WaitGroup
+	for i := 0; i < le; i++ {
+		wg.Add(1)
+		go func() {
+			defer wg.Done()
+			id := snowflake.ID()
+			ch <- id
+		}()
+	}
+	wg.Wait()
+	close(ch)
+
+	mp := make(map[uint64]bool)
+	for id := range ch {
+		if _, ok := mp[id]; ok {
+			t.Error("It should not be repeated")
+			break
+		}
+		mp[id] = true
+	}
+	if len(mp) != le {
+		t.Error("map length should be equal", le)
+	}
 }
 
 func TestSetStartTime(t *testing.T) {