add option for forcing each worker to have separate connection

.golangci.yml

@@ -39,7 +39,8 @@ linters-settings:
     - '^ @.*' # swaggo comments like // @title
     - '^ (\d+)(\.|\)).*' # enumeration comments like // 1. or // 1)
   gosec:
-    global:
-      audit: true
+    config:
+      global:
+        audit: true
     excludes:
     - G104

cmd/root.go

@@ -152,6 +152,10 @@ func init() {
 		"If the file does not exist, the file will be created.").
 		Default(dnsbench.DefaultRequestLogPath).StringVar(&benchmark.RequestLogPath)
 
+	pApp.Flag("separate-worker-connections", "Controls whether the concurrent workers will try to share connections to the server or not. When enabled "+
+		"the workers will use separate connections. Disabled by default.").
+		Default("false").BoolVar(&benchmark.SeparateWorkerConnections)
+
 	pApp.Arg("queries", "Queries to issue. It can be a local file referenced using @<file-path>, for example @data/2-domains. "+
 		"It can also be resource accessible using HTTP, like https://raw.githubusercontent.com/Tantalor93/dnspyre/master/data/1000-domains, in that "+
 		"case, the file will be downloaded and saved in-memory. "+

docs/doh.md

@@ -5,8 +5,6 @@ parent: Examples
 ---
 
 # DoH
-{: .no_toc }
-
 *dnspyre* supports running benchmarks against [RFC-8484](https://www.rfc-editor.org/rfc/rfc8484) compatible DNS over HTTPS servers
 
 ```

docs/dot.md

@@ -5,8 +5,6 @@ parent: Examples
 ---
 
 # DoT
-{: .no_toc }
-
 *dnspyre* supports running benchmarks against [RFC-7858](https://datatracker.ietf.org/doc/html/rfc7858) compatible DNS over TLS servers
 
 ```

docs/workerconnections.md

@@ -0,0 +1,22 @@
+---
+title: Configuring connection sharing
+layout: default
+parent: Examples
+---
+
+# Configuring connection sharing
+v3.3.0
+{: .label .label-yellow }
+*dnspyre* by default tries to share connections between spawned concurrent workers as much as possible, so for example 
+if DoH benchmark over HTTPS/2 with multiple concurrent workers is executed, then all the workers will share same single HTTPS/2 connection 
+to the DNS server
+
+```
+dnspyre --server https://1.1.1.1 google.com -c 5 --doh-protocol 2
+```
+
+If you want to avoid sharing connection between concurrent workers, you can use `--separate-worker-connections` flag
+
+```
+dnspyre --server https://1.1.1.1 google.com -c 5 --doh-protocol 2 --separate-worker-connections
+```

pkg/dnsbench/benchmark.go

@@ -190,6 +190,10 @@ type Benchmark struct {
 	// If it exists, the request logs are appended to the file.
 	RequestLogPath string
 
+	// SeparateWorkerConnections controls whether the concurrent workers will try to share connections to the server or not. When set true,
+	// the workers will NOT share connections and each worker will have separate connection.
+	SeparateWorkerConnections bool
+
 	// Writer used for writing benchmark execution logs and results. Default is os.Stdout.
 	Writer io.Writer
 
@@ -200,8 +204,8 @@ type Benchmark struct {
 
 type queryFunc func(context.Context, string, *dns.Msg) (*dns.Msg, error)
 
-// prepare validates and normalizes Benchmark settings.
-func (b *Benchmark) prepare() error {
+// init validates and normalizes Benchmark settings.
+func (b *Benchmark) init() error {
 	if b.Writer == nil {
 		b.Writer = os.Stdout
 	}
@@ -259,7 +263,7 @@ func (b *Benchmark) prepare() error {
 		}
 	}
 
-	if b.RequestLogEnabled {
+	if b.RequestLogEnabled && len(b.RequestLogPath) == 0 {
 		b.RequestLogPath = DefaultRequestLogPath
 	}
 
@@ -268,6 +272,12 @@ func (b *Benchmark) prepare() error {
 
 // Run executes benchmark, if benchmark is unable to start the error is returned, otherwise array of results from parallel benchmark goroutines is returned.
 func (b *Benchmark) Run(ctx context.Context) ([]*ResultStats, error) {
+	color.NoColor = !b.Color
+
+	if err := b.init(); err != nil {
+		return nil, err
+	}
+
 	if b.RequestLogEnabled {
 		file, err := os.OpenFile(b.RequestLogPath, os.O_CREATE|os.O_WRONLY|os.O_APPEND, 0o644)
 		if err != nil {
@@ -277,12 +287,6 @@ func (b *Benchmark) Run(ctx context.Context) ([]*ResultStats, error) {
 		log.SetOutput(file)
 	}
 
-	color.NoColor = !b.Color
-
-	if err := b.prepare(); err != nil {
-		return nil, err
-	}
-
 	questions, err := b.prepareQuestions()
 	if err != nil {
 		return nil, err
@@ -499,13 +503,32 @@ func (b *Benchmark) queryFactory() func() queryFunc {
 	// and granular control of the connection
 	switch {
 	case b.useDoH:
+		if b.SeparateWorkerConnections {
+			return func() queryFunc {
+				dohQuery := b.dohQuery()
+				return dohQuery
+			}
+		}
 		dohQuery := b.dohQuery()
-		queryFactory := func() queryFunc {
+		return func() queryFunc {
 			return dohQuery
 		}
-		return queryFactory
 	case b.useQuic:
 		h, _, _ := net.SplitHostPort(b.Server)
+		if b.SeparateWorkerConnections {
+			return func() queryFunc {
+				// nolint:gosec
+				quicClient := doq.NewClient(b.Server, doq.Options{
+					TLSConfig:      &tls.Config{ServerName: h, InsecureSkipVerify: b.Insecure},
+					ReadTimeout:    b.ReadTimeout,
+					WriteTimeout:   b.WriteTimeout,
+					ConnectTimeout: b.ConnectTimeout,
+				})
+				return func(ctx context.Context, _ string, msg *dns.Msg) (*dns.Msg, error) {
+					return quicClient.Send(ctx, msg)
+				}
+			}
+		}
 		// nolint:gosec
 		quicClient := doq.NewClient(b.Server, doq.Options{
 			TLSConfig:      &tls.Config{ServerName: h, InsecureSkipVerify: b.Insecure},

pkg/dnsbench/benchmark_api_test.go

@@ -15,10 +15,12 @@ import (
 	"os"
 	"regexp"
 	"strconv"
+	"sync"
 	"testing"
 	"time"
 
 	"github.com/miekg/dns"
+	"github.com/quic-go/quic-go"
 	"github.com/stretchr/testify/assert"
 	"github.com/stretchr/testify/require"
 	"github.com/tantalor93/dnspyre/v3/pkg/dnsbench"
@@ -726,7 +728,7 @@ func TestBenchmark_Run_PlainDNS_default_count(t *testing.T) {
 }
 
 func TestBenchmark_Run_DoQ(t *testing.T) {
-	server := newDoQServer(func(r *dns.Msg) *dns.Msg {
+	server := newDoQServer(func(_ quic.Connection, r *dns.Msg) *dns.Msg {
 		ret := new(dns.Msg)
 		ret.SetReply(r)
 		ret.Answer = append(ret.Answer, A("example.org. IN A 127.0.0.1"))
@@ -1033,7 +1035,7 @@ func TestBenchmark_Run_DoH_error(t *testing.T) {
 }
 
 func TestBenchmark_Run_DoQ_error(t *testing.T) {
-	server := newDoQServer(func(_ *dns.Msg) *dns.Msg {
+	server := newDoQServer(func(_ quic.Connection, _ *dns.Msg) *dns.Msg {
 		return nil
 	})
 	server.start()
@@ -1238,7 +1240,7 @@ func TestBenchmark_Run_DoH_truncated(t *testing.T) {
 }
 
 func TestBenchmark_Run_DoQ_truncated(t *testing.T) {
-	server := newDoQServer(func(r *dns.Msg) *dns.Msg {
+	server := newDoQServer(func(_ quic.Connection, r *dns.Msg) *dns.Msg {
 		ret := new(dns.Msg)
 		ret.SetReply(r)
 		ret.Answer = append(ret.Answer, A("example.org. IN A 127.0.0.1"))
@@ -1359,6 +1361,192 @@ func TestBenchmark_Requestlog(t *testing.T) {
 	assert.Equal(t, map[string]int{"AAAA": 2, "A": 2}, qtypes)
 }
 
+func TestBenchmark_Run_DoH_separate_connections(t *testing.T) {
+	tests := []struct {
+		name                    string
+		separateConnections     bool
+		wantNumberOfConnections int
+	}{
+		{
+			name:                    "separate connections",
+			separateConnections:     true,
+			wantNumberOfConnections: 5,
+		},
+		{
+			name:                    "shared connections",
+			separateConnections:     false,
+			wantNumberOfConnections: 1,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			cert, err := tls.LoadX509KeyPair("testdata/test.crt", "testdata/test.key")
+			require.NoError(t, err)
+
+			certs, err := os.ReadFile("testdata/test.crt")
+			require.NoError(t, err)
+
+			pool, err := x509.SystemCertPool()
+			require.NoError(t, err)
+
+			pool.AppendCertsFromPEM(certs)
+			config := tls.Config{
+				ServerName:   "localhost",
+				RootCAs:      pool,
+				Certificates: []tls.Certificate{cert},
+				MinVersion:   tls.VersionTLS12,
+			}
+
+			mutex := sync.Mutex{}
+			remoteAddrs := make(map[string]int)
+
+			ts := httptest.NewUnstartedServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+				mutex.Lock()
+				remoteAddrs[r.RemoteAddr]++
+				mutex.Unlock()
+
+				bd, err := io.ReadAll(r.Body)
+				if err != nil {
+					panic(err)
+				}
+
+				msg := dns.Msg{}
+				err = msg.Unpack(bd)
+				if err != nil {
+					panic(err)
+				}
+
+				msg.Answer = append(msg.Answer, A("example.org. IN A 127.0.0.1"))
+
+				pack, err := msg.Pack()
+				if err != nil {
+					panic(err)
+				}
+
+				_, err = w.Write(pack)
+				if err != nil {
+					panic(err)
+				}
+			}))
+			ts.EnableHTTP2 = true
+			ts.TLS = &config
+			ts.StartTLS()
+			defer ts.Close()
+
+			buf := bytes.Buffer{}
+			bench := dnsbench.Benchmark{
+				Queries:                   []string{"example.org"},
+				Types:                     []string{"A"},
+				Server:                    ts.URL,
+				DohProtocol:               "2",
+				TCP:                       true,
+				Concurrency:               5,
+				Count:                     2,
+				Probability:               1,
+				WriteTimeout:              1 * time.Second,
+				ReadTimeout:               3 * time.Second,
+				ConnectTimeout:            1 * time.Second,
+				RequestTimeout:            5 * time.Second,
+				Rcodes:                    true,
+				Recurse:                   true,
+				DohMethod:                 dnsbench.PostHTTPMethod,
+				Writer:                    &buf,
+				SeparateWorkerConnections: tt.separateConnections,
+				Insecure:                  true,
+			}
+
+			ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+			defer cancel()
+			rs, err := bench.Run(ctx)
+
+			// close right away to mitigate race detector failures
+			ts.Close()
+
+			require.NoError(t, err, "expected no error from benchmark run")
+			assert.Len(t, rs, 5)
+			for _, v := range rs {
+				assert.Empty(t, v.Errors)
+			}
+			assert.Len(t, remoteAddrs, tt.wantNumberOfConnections)
+			assert.Equal(t, fmt.Sprintf("Using 1 hostnames\nBenchmarking %s/dns-query via https/2 (POST) with 5 concurrent requests \n", ts.URL), buf.String())
+		})
+	}
+}
+
+func TestBenchmark_Run_DoQ_separate_connections(t *testing.T) {
+	tests := []struct {
+		name                    string
+		separateConnections     bool
+		wantNumberOfConnections int
+	}{
+		{
+			name:                    "separate connections",
+			separateConnections:     true,
+			wantNumberOfConnections: 5,
+		},
+		{
+			name:                    "shared connections",
+			separateConnections:     false,
+			wantNumberOfConnections: 1,
+		},
+	}
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			mutex := sync.Mutex{}
+			remoteAddrs := make(map[string]int)
+
+			server := newDoQServer(func(c quic.Connection, r *dns.Msg) *dns.Msg {
+				mutex.Lock()
+				remoteAddrs[c.RemoteAddr().String()]++
+				mutex.Unlock()
+
+				ret := new(dns.Msg)
+				ret.SetReply(r)
+				ret.Answer = append(ret.Answer, A("example.org. IN A 127.0.0.1"))
+				return ret
+			})
+			server.start()
+			defer server.stop()
+
+			buf := bytes.Buffer{}
+			bench := dnsbench.Benchmark{
+				Queries:                   []string{"example.org"},
+				Types:                     []string{"A"},
+				Server:                    "quic://" + server.addr,
+				TCP:                       true,
+				Concurrency:               5,
+				Count:                     2,
+				Probability:               1,
+				WriteTimeout:              1 * time.Second,
+				ReadTimeout:               3 * time.Second,
+				ConnectTimeout:            1 * time.Second,
+				RequestTimeout:            5 * time.Second,
+				Rcodes:                    true,
+				Recurse:                   true,
+				DohMethod:                 dnsbench.PostHTTPMethod,
+				Writer:                    &buf,
+				SeparateWorkerConnections: tt.separateConnections,
+				Insecure:                  true,
+			}
+
+			ctx, cancel := context.WithTimeout(context.Background(), 30*time.Second)
+			defer cancel()
+			rs, err := bench.Run(ctx)
+
+			// stop right away to mitigate race detector failures
+			server.stop()
+
+			require.NoError(t, err, "expected no error from benchmark run")
+			assert.Len(t, rs, 5)
+			for _, v := range rs {
+				assert.Empty(t, v.Errors)
+			}
+			assert.Len(t, remoteAddrs, tt.wantNumberOfConnections)
+			assert.Equal(t, fmt.Sprintf("Using 1 hostnames\nBenchmarking %s via quic with 5 concurrent requests \n", server.addr), buf.String())
+		})
+	}
+}
+
 func parseRequestLogs(t *testing.T, reader io.Reader) []requestLog {
 	pattern := `.*worker:\[(.*)\] reqid:\[(.*)\] qname:\[(.*)\] qtype:\[(.*)\] respid:\[(.*)\] rcode:\[(.*)\] respflags:\[(.*)\] err:\[(.*)\] duration:\[(.*)\]$`
 	regex := regexp.MustCompile(pattern)