From 1d51515945e950f8bbe8b40e8da0b4ff437a7f62 Mon Sep 17 00:00:00 2001
From: Bruce Marriner <bruce@sqls.net>
Date: Wed, 10 Apr 2019 01:02:19 +0000
Subject: [PATCH 1/7] An attempt at catching race issues

---
 snowflake_test.go | 20 ++++++++++++++++++++
 1 file changed, 20 insertions(+)

diff --git a/snowflake_test.go b/snowflake_test.go
index 2f25f22..a454e5a 100644
--- a/snowflake_test.go
+++ b/snowflake_test.go
@@ -6,6 +6,25 @@ import (
 	"testing"
 )
 
+// I feel like there's probably a better way
+func TestRace(t *testing.T) {
+
+	node, _ := NewNode(1)
+
+	go func() {
+		for i := 0; i < 1000000000; i++ {
+
+			NewNode(1)
+		}
+	}()
+
+	for i := 0; i < 4000; i++ {
+
+		node.Generate()
+	}
+
+}
+
 func TestMarshalJSON(t *testing.T) {
 	id := ID(13587)
 	expected := "\"13587\""
@@ -112,6 +131,7 @@ func TestBase58(t *testing.T) {
 		}
 	}
 }
+
 func BenchmarkParseBase58(b *testing.B) {
 
 	node, _ := NewNode(1)

From c3f55288095a0daf0d267bcf68f8f80799dd4e0e Mon Sep 17 00:00:00 2001
From: Bruce Marriner <bruce@sqls.net>
Date: Wed, 10 Apr 2019 01:06:02 +0000
Subject: [PATCH 2/7] Check more, Check against Go 11.x/12.x

---
 .travis.yml | 13 ++++++++-----
 1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/.travis.yml b/.travis.yml
index 0ce1bba..d817401 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,8 +1,11 @@
 language: go
 go:
-    - 1.4
-    - 1.5
-    - 1.6
+    - 1.11.x
+    - 1.12.x
 install:
-      - go get github.com/bwmarrin/flake
-      - go get -v .
+    - go get -v .
+script:
+    - diff <(gofmt -d .) <(echo -n)
+    - go vet -x ./...
+    - golint -set_exit_status ./...
+    - go test -v -race ./...

From 272c8fb2159cd0d0a451433bb1613944508bd679 Mon Sep 17 00:00:00 2001
From: Bruce Marriner <bruce@sqls.net>
Date: Wed, 10 Apr 2019 01:12:21 +0000
Subject: [PATCH 3/7] =?UTF-8?q?=F0=9F=91=8CLinting?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

---
 snowflake.go      | 12 ++++++------
 snowflake_test.go |  6 +++---
 2 files changed, 9 insertions(+), 9 deletions(-)

diff --git a/snowflake.go b/snowflake.go
index f112a05..0462cd7 100644
--- a/snowflake.go
+++ b/snowflake.go
@@ -16,19 +16,19 @@ var (
 	// You may customize this to set a different epoch for your application.
 	Epoch int64 = 1288834974657
 
-	// Number of bits to use for Node
+	// NodeBits holds the number of bits to use for Node
 	// Remember, you have a total 22 bits to share between Node/Step
 	NodeBits uint8 = 10
 
-	// Number of bits to use for Step
+	// StepBits holds the number of bits to use for Step
 	// Remember, you have a total 22 bits to share between Node/Step
 	StepBits uint8 = 12
 
 	nodeMax   int64 = -1 ^ (-1 << NodeBits)
-	nodeMask  int64 = nodeMax << StepBits
+	nodeMask        = nodeMax << StepBits
 	stepMask  int64 = -1 ^ (-1 << StepBits)
-	timeShift uint8 = NodeBits + StepBits
-	nodeShift uint8 = StepBits
+	timeShift       = NodeBits + StepBits
+	nodeShift       = StepBits
 )
 
 const encodeBase32Map = "ybndrfg8ejkmcpqxot1uwisza345h769"
@@ -95,7 +95,7 @@ func NewNode(node int64) (*Node, error) {
 	stepMask = -1 ^ (-1 << StepBits)
 	timeShift = NodeBits + StepBits
 	nodeShift = StepBits
-	
+
 	if node < 0 || node > nodeMax {
 		return nil, errors.New("Node number must be between 0 and " + strconv.FormatInt(nodeMax, 10))
 	}
diff --git a/snowflake_test.go b/snowflake_test.go
index a454e5a..18f5d9f 100644
--- a/snowflake_test.go
+++ b/snowflake_test.go
@@ -50,7 +50,7 @@ func TestMarshalsIntBytes(t *testing.T) {
 func TestUnmarshalJSON(t *testing.T) {
 	tt := []struct {
 		json        string
-		expectedId  ID
+		expectedID  ID
 		expectedErr error
 	}{
 		{`"13587"`, 13587, nil},
@@ -65,8 +65,8 @@ func TestUnmarshalJSON(t *testing.T) {
 			t.Errorf("Expected to get error '%s' decoding JSON, but got '%s'", tc.expectedErr, err)
 		}
 
-		if id != tc.expectedId {
-			t.Errorf("Expected to get ID '%s' decoding JSON, but got '%s'", tc.expectedId, id)
+		if id != tc.expectedID {
+			t.Errorf("Expected to get ID '%s' decoding JSON, but got '%s'", tc.expectedID, id)
 		}
 	}
 }

From 0de6e0c0745b50e7bc88c91219d482ad92c4d255 Mon Sep 17 00:00:00 2001
From: Bruce Marriner <bruce@sqls.net>
Date: Wed, 10 Apr 2019 01:21:34 +0000
Subject: [PATCH 4/7] Don't let tests skew benchmark

---
 README.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/README.md b/README.md
index cc029d6..0e6623c 100644
--- a/README.md
+++ b/README.md
@@ -135,7 +135,7 @@ To benchmark the generator on your system run the following command inside the
 snowflake package directory.
 
 ```sh
-go test -bench=.
+go test -run=^$ -bench=.
 ```
 
 If your curious, check out this commit that shows benchmarks that compare a few 

From 267d02f8b9813a5375a1b8b58ff051a8c245ca8b Mon Sep 17 00:00:00 2001
From: Bruce Marriner <bruce@sqls.net>
Date: Wed, 10 Apr 2019 01:32:30 +0000
Subject: [PATCH 5/7] Add BenchmarkGenerateMaxSequence func

This allows a benchmark showing how fast ids can be generated with 21
bits assigned to the sequence number
---
 snowflake_test.go | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/snowflake_test.go b/snowflake_test.go
index 18f5d9f..3d84763 100644
--- a/snowflake_test.go
+++ b/snowflake_test.go
@@ -169,6 +169,20 @@ func BenchmarkGenerate(b *testing.B) {
 	}
 }
 
+func BenchmarkGenerateMaxSequence(b *testing.B) {
+
+	NodeBits = 1
+	StepBits = 21
+	node, _ := NewNode(1)
+
+	b.ReportAllocs()
+
+	b.ResetTimer()
+	for n := 0; n < b.N; n++ {
+		_ = node.Generate()
+	}
+}
+
 func BenchmarkUnmarshal(b *testing.B) {
 	// Generate the ID to unmarshal
 	node, _ := NewNode(1)

From 20ab5dc6a45e1c57b60936ea1d26f9c72d22ade9 Mon Sep 17 00:00:00 2001
From: Bruce Marriner <bruce@sqls.net>
Date: Wed, 10 Apr 2019 01:33:37 +0000
Subject: [PATCH 6/7] Deprecate several global variables

This allows better data race protection and makes it more possible to
have multi nodes running on the same program with different options. A
temp global mutex was added to protect data races caused by NewNode
until the deprecated variables are removed. fixed #15
---
 snowflake.go | 38 ++++++++++++++++++++++++++++----------
 1 file changed, 28 insertions(+), 10 deletions(-)

diff --git a/snowflake.go b/snowflake.go
index 0462cd7..a5952a9 100644
--- a/snowflake.go
+++ b/snowflake.go
@@ -24,6 +24,8 @@ var (
 	// Remember, you have a total 22 bits to share between Node/Step
 	StepBits uint8 = 12
 
+	// DEPRECATED: the below four variables will be removed in a future release.
+	mu        sync.Mutex
 	nodeMax   int64 = -1 ^ (-1 << NodeBits)
 	nodeMask        = nodeMax << StepBits
 	stepMask  int64 = -1 ^ (-1 << StepBits)
@@ -79,6 +81,12 @@ type Node struct {
 	time int64
 	node int64
 	step int64
+
+	nodeMax   int64
+	nodeMask  int64
+	stepMask  int64
+	timeShift uint8
+	nodeShift uint8
 }
 
 // An ID is a custom type used for a snowflake ID.  This is used so we can
@@ -90,21 +98,28 @@ type ID int64
 func NewNode(node int64) (*Node, error) {
 
 	// re-calc in case custom NodeBits or StepBits were set
+	// DEPRECATED: the below block will be removed in a future release.
+	mu.Lock()
 	nodeMax = -1 ^ (-1 << NodeBits)
 	nodeMask = nodeMax << StepBits
 	stepMask = -1 ^ (-1 << StepBits)
 	timeShift = NodeBits + StepBits
 	nodeShift = StepBits
+	mu.Unlock()
 
-	if node < 0 || node > nodeMax {
-		return nil, errors.New("Node number must be between 0 and " + strconv.FormatInt(nodeMax, 10))
+	n := Node{}
+	n.node = node
+	n.nodeMax = -1 ^ (-1 << NodeBits)
+	n.nodeMask = n.nodeMax << StepBits
+	n.stepMask = -1 ^ (-1 << StepBits)
+	n.timeShift = NodeBits + StepBits
+	n.nodeShift = StepBits
+
+	if n.node < 0 || n.node > n.nodeMax {
+		return nil, errors.New("Node number must be between 0 and " + strconv.FormatInt(n.nodeMax, 10))
 	}
 
-	return &Node{
-		time: 0,
-		node: node,
-		step: 0,
-	}, nil
+	return &n, nil
 }
 
 // Generate creates and returns a unique snowflake ID
@@ -115,7 +130,7 @@ func (n *Node) Generate() ID {
 	now := time.Now().UnixNano() / 1000000
 
 	if n.time == now {
-		n.step = (n.step + 1) & stepMask
+		n.step = (n.step + 1) & n.stepMask
 
 		if n.step == 0 {
 			for now <= n.time {
@@ -128,8 +143,8 @@ func (n *Node) Generate() ID {
 
 	n.time = now
 
-	r := ID((now-Epoch)<<timeShift |
-		(n.node << nodeShift) |
+	r := ID((now-Epoch)<<n.timeShift |
+		(n.node << n.nodeShift) |
 		(n.step),
 	)
 
@@ -253,16 +268,19 @@ func (f ID) IntBytes() [8]byte {
 }
 
 // Time returns an int64 unix timestamp of the snowflake ID time
+// DEPRECATED: the below function will be removed in a future release.
 func (f ID) Time() int64 {
 	return (int64(f) >> timeShift) + Epoch
 }
 
 // Node returns an int64 of the snowflake ID node number
+// DEPRECATED: the below function will be removed in a future release.
 func (f ID) Node() int64 {
 	return int64(f) & nodeMask >> nodeShift
 }
 
 // Step returns an int64 of the snowflake step (or sequence) number
+// DEPRECATED: the below function will be removed in a future release.
 func (f ID) Step() int64 {
 	return int64(f) & stepMask
 }

From 74a8a18aca3be8b9df1532dc1ee0ddaa38d5dc49 Mon Sep 17 00:00:00 2001
From: Bruce Marriner <bruce@sqls.net>
Date: Wed, 10 Apr 2019 01:41:37 +0000
Subject: [PATCH 7/7] Install golint:)

---
 .travis.yml | 1 +
 1 file changed, 1 insertion(+)

diff --git a/.travis.yml b/.travis.yml
index d817401..75d9f5c 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -4,6 +4,7 @@ go:
     - 1.12.x
 install:
     - go get -v .
+    - go get -v golang.org/x/lint/golint
 script:
     - diff <(gofmt -d .) <(echo -n)
     - go vet -x ./...