Merge pull request #23 from hurbcom/feature/add-thread-helper

add thread helper

lib/thread.go

@@ -0,0 +1,23 @@
+package lib
+
+import (
+	"context"
+
+	"golang.org/x/sync/errgroup"
+)
+
+// ErrorGroup resolves all go routines. It fails at first error encountered
+// warning: Creating goroutines in the args will cause them to run in background
+func ErrorGroup(ctx context.Context, args ...func() error) error {
+	g, _ := errgroup.WithContext(ctx)
+
+	for _, fn := range args {
+		g.Go(fn)
+	}
+
+	if err := g.Wait(); err != nil {
+		return err
+	}
+
+	return nil
+}

lib/thread_test.go

@@ -0,0 +1,56 @@
+package lib
+
+import (
+	"context"
+	"errors"
+	"testing"
+)
+
+func TestErrorGroup(t *testing.T) {
+	type args struct {
+		ctx  context.Context
+		args []func() error
+	}
+	tests := []struct {
+		name    string
+		args    args
+		wantErr bool
+	}{
+		{
+			name: "Should run successfully when all go routines complete successfully",
+			args: args{
+				ctx: context.Background(),
+				args: []func() error{
+					func() error {
+						return nil
+					},
+					func() error {
+						return nil
+					},
+				},
+			},
+		},
+		{
+			name: "Should fail when first go routine fails",
+			args: args{
+				ctx: context.Background(),
+				args: []func() error{
+					func() error {
+						return errors.New("Oops, you received an error")
+					},
+					func() error {
+						return nil
+					},
+				},
+			},
+			wantErr: true,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			if err := ErrorGroup(tt.args.ctx, tt.args.args...); (err != nil) != tt.wantErr {
+				t.Errorf("ErrorGroup() error = %v, wantErr %v", err, tt.wantErr)
+			}
+		})
+	}
+}