Initial

5 files changed, 153 insertions, 0 deletions

diff --git a/channels/doc.go b/channels/doc.go
new file mode 100644
index 0000000..0ac1c76
--- /dev/null
+++ b/channels/doc.go
@@ -0,0 +1,2 @@
+// Функции работы над каналами
+package channels
diff --git a/channels/fanin.go b/channels/fanin.go
new file mode 100644
index 0000000..679aeee
--- /dev/null
+++ b/channels/fanin.go
@@ -0,0 +1,23 @@
+package channels
+
+import "sync/atomic"
+
+// FanIn сливает несколько каналов в один
+func FanIn[T any](chans ...chan T) chan T {
+	out := make(chan T)
+	workers := int64(len(chans))
+	for _, ch := range chans {
+		func(ch chan T) {
+			go func() {
+				for t := range ch {
+					out <- t
+				}
+				atomic.AddInt64(&workers, -1)
+				if workers == 0 {
+					close(out)
+				}
+			}()
+		}(ch)
+	}
+	return out
+}
diff --git a/channels/fanin_test.go b/channels/fanin_test.go
new file mode 100644
index 0000000..dd0c889
--- /dev/null
+++ b/channels/fanin_test.go
@@ -0,0 +1,57 @@
+package channels
+
+import (
+	"reflect"
+	"sort"
+	"testing"
+)
+
+func TestFanIn(t *testing.T) {
+	type args struct {
+		chans [][]int
+	}
+	tests := []struct {
+		name string
+		args args
+		want []int
+	}{
+		{
+			name: "test fanin",
+			args: args{
+				chans: [][]int{
+					{1, 2, 3},
+					{4, 5, 6},
+					{7, 8, 9},
+				},
+			},
+			want: []int{1, 2, 3, 4, 5, 6, 7, 8, 9},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			got := []int{}
+			chans := make([]chan int, len(tt.args.chans))
+			for i, v := range tt.args.chans {
+				func(i int, v []int) {
+					chans[i] = make(chan int, len(v))
+					go func(i int, v []int) {
+						for _, v2 := range v {
+							chans[i] <- v2
+						}
+						close(chans[i])
+					}(i, v)
+				}(i, v)
+			}
+
+			ch := FanIn(chans...)
+
+			for o := range ch {
+				got = append(got, o)
+			}
+			sort.Ints(got)
+			if !reflect.DeepEqual(got, tt.want) {
+				t.Errorf("FanIn() = %v, want %v", got, tt.want)
+			}
+		})
+	}
+}
diff --git a/channels/fanout.go b/channels/fanout.go
new file mode 100644
index 0000000..23a32b4
--- /dev/null
+++ b/channels/fanout.go
@@ -0,0 +1,23 @@
+package channels
+
+// FanOut раскидывает очередь канала на несколько каналов равномерно
+func FanOut[T any](in chan T, workers int) []chan T {
+	out := make([]chan T, workers)
+	for i := 0; i < workers; i++ {
+		out[i] = make(chan T)
+	}
+	go func() {
+		i := 0
+		for t := range in {
+			out[i] <- t
+			i++
+			if i == workers {
+				i = 0
+			}
+		}
+		for i := 0; i < workers; i++ {
+			close(out[i])
+		}
+	}()
+	return out
+}
diff --git a/channels/fanout_test.go b/channels/fanout_test.go
new file mode 100644
index 0000000..f8b0380
--- /dev/null
+++ b/channels/fanout_test.go
@@ -0,0 +1,48 @@
+package channels
+
+import (
+	"reflect"
+	"sort"
+	"testing"
+)
+
+func TestFanOut(t *testing.T) {
+	type args struct {
+		in      []int
+		workers int
+	}
+	tests := []struct {
+		name string
+		args args
+	}{
+		{
+			name: "test fanout - fanin",
+			args: args{
+				in:      []int{1, 2, 3, 4, 5, 6, 7, 8, 9},
+				workers: 2,
+			},
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			in := make(chan int)
+			go func() {
+				for _, v := range tt.args.in {
+					in <- v
+				}
+				close(in)
+			}()
+
+			ch := FanOut(in, tt.args.workers)
+			gotCh := FanIn(ch...)
+			got := []int{}
+			for v := range gotCh {
+				got = append(got, v)
+			}
+			sort.Ints(got)
+			if !reflect.DeepEqual(got, tt.args.in) {
+				t.Errorf("FanIn() = %v, want %v", got, tt.args.in)
+			}
+		})
+	}
+}