TUN-5138: Switch to QUIC on auto protocol based on threshold

cmd/cloudflared/tunnel/configuration.go

@@ -238,7 +238,7 @@ func prepareTunnelConfig(
 		log.Info().Msgf("Warp-routing is enabled")
 	}
 
-	protocolSelector, err := connection.NewProtocolSelector(c.String("protocol"), warpRoutingEnabled, namedTunnel, edgediscovery.HTTP2Percentage, origin.ResolveTTL, log)
+	protocolSelector, err := connection.NewProtocolSelector(c.String("protocol"), warpRoutingEnabled, namedTunnel, edgediscovery.ProtocolPercentage, origin.ResolveTTL, log)
 	if err != nil {
 		return nil, ingress.Ingress{}, err
 	}

connection/protocol.go

@@ -7,6 +7,8 @@ import (
 	"time"
 
 	"github.com/rs/zerolog"
+
+	"github.com/cloudflare/cloudflared/edgediscovery"
 )
 
 const (
@@ -24,7 +26,7 @@ const (
 
 var (
 	// ProtocolList represents a list of supported protocols for communication with the edge.
-	ProtocolList = []Protocol{H2mux, HTTP2, QUIC}
+	ProtocolList = []Protocol{H2mux, HTTP2, HTTP2Warp, QUIC, QUICWarp}
 )
 
 type Protocol int64
@@ -36,6 +38,12 @@ const (
 	HTTP2
 	// QUIC is used only with named tunnels.
 	QUIC
+	// HTTP2Warp is used only with named tunnels. It's useful for warp-routing where we don't want to fallback to
+	// H2mux on HTTP2 failure to connect.
+	HTTP2Warp
+	//QUICWarp is used only with named tunnels. It's useful for warp-routing where we want to fallback to HTTP2 but
+	// dont' want HTTP2 to fallback to H2mux
+	QUICWarp
 )
 
 // Fallback returns the fallback protocol and whether the protocol has a fallback
@@ -45,8 +53,12 @@ func (p Protocol) fallback() (Protocol, bool) {
 		return 0, false
 	case HTTP2:
 		return H2mux, true
+	case HTTP2Warp:
+		return 0, false
 	case QUIC:
 		return HTTP2, true
+	case QUICWarp:
+		return HTTP2Warp, true
 	default:
 		return 0, false
 	}
@@ -56,9 +68,9 @@ func (p Protocol) String() string {
 	switch p {
 	case H2mux:
 		return "h2mux"
-	case HTTP2:
+	case HTTP2, HTTP2Warp:
 		return "http2"
-	case QUIC:
+	case QUIC, QUICWarp:
 		return "quic"
 	default:
 		return fmt.Sprintf("unknown protocol")
@@ -71,11 +83,11 @@ func (p Protocol) TLSSettings() *TLSSettings {
 		return &TLSSettings{
 			ServerName: edgeH2muxTLSServerName,
 		}
-	case HTTP2:
+	case HTTP2, HTTP2Warp:
 		return &TLSSettings{
 			ServerName: edgeH2TLSServerName,
 		}
-	case QUIC:
+	case QUIC, QUICWarp:
 		return &TLSSettings{
 			ServerName: edgeQUICServerName,
 			NextProtos: []string{"argotunnel"},
@@ -109,8 +121,13 @@ func (s *staticProtocolSelector) Fallback() (Protocol, bool) {
 
 type autoProtocolSelector struct {
 	lock sync.RWMutex
+
 	current Protocol
-	switchThrehold int32
+
+	// protocolPool is desired protocols in the order of priority they should be picked in.
+	protocolPool []Protocol
+
+	switchThreshold int32
 	fetchFunc       PercentageFetcher
 	refreshAfter    time.Time
 	ttl             time.Duration
@@ -119,14 +136,16 @@ type autoProtocolSelector struct {
 
 func newAutoProtocolSelector(
 	current Protocol,
-	switchThrehold int32,
+	protocolPool []Protocol,
+	switchThreshold int32,
 	fetchFunc PercentageFetcher,
 	ttl time.Duration,
 	log *zerolog.Logger,
 ) *autoProtocolSelector {
 	return &autoProtocolSelector{
 		current:         current,
-		switchThrehold: switchThrehold,
+		protocolPool:    protocolPool,
+		switchThreshold: switchThreshold,
 		fetchFunc:       fetchFunc,
 		refreshAfter:    time.Now().Add(ttl),
 		ttl:             ttl,
@@ -141,28 +160,39 @@ func (s *autoProtocolSelector) Current() Protocol {
 		return s.current
 	}
 
-	percentage, err := s.fetchFunc()
+	protocol, err := getProtocol(s.protocolPool, s.fetchFunc, s.switchThreshold)
 	if err != nil {
 		s.log.Err(err).Msg("Failed to refresh protocol")
 		return s.current
 	}
+	s.current = protocol
 
-	if s.switchThrehold < percentage {
-		s.current = HTTP2
-	} else {
-		s.current = H2mux
-	}
 	s.refreshAfter = time.Now().Add(s.ttl)
 	return s.current
 }
 
+func getProtocol(protocolPool []Protocol, fetchFunc PercentageFetcher, switchThreshold int32) (Protocol, error) {
+	protocolPercentages, err := fetchFunc()
+	if err != nil {
+		return 0, err
+	}
+	for _, protocol := range protocolPool {
+		protocolPercentage := protocolPercentages.GetPercentage(protocol.String())
+		if protocolPercentage > switchThreshold {
+			return protocol, nil
+		}
+	}
+
+	return protocolPool[len(protocolPool)-1], nil
+}
+
 func (s *autoProtocolSelector) Fallback() (Protocol, bool) {
 	s.lock.RLock()
 	defer s.lock.RUnlock()
 	return s.current.fallback()
 }
 
-type PercentageFetcher func() (int32, error)
+type PercentageFetcher func() (edgediscovery.ProtocolPercents, error)
 
 func NewProtocolSelector(
 	protocolFlag string,
@@ -179,22 +209,34 @@ func NewProtocolSelector(
 		}, nil
 	}
 
-	// warp routing cannot be served over h2mux connections
+	threshold := switchThreshold(namedTunnel.Credentials.AccountTag)
-	if warpRoutingEnabled {
+	fetchedProtocol, err := getProtocol([]Protocol{QUIC, HTTP2}, fetchFunc, threshold)
-		if protocolFlag == H2mux.String() {
+	if err != nil {
-			log.Warn().Msg("Warp routing is not supported in h2mux protocol. Upgrading to http2 to allow it.")
+		log.Err(err).Msg("Unable to lookup protocol. Defaulting to `http2`. If this fails, you can set `--protocol h2mux` in your cloudflared command.")
-		}
-
-		if protocolFlag == QUIC.String() {
-			return &staticProtocolSelector{
-				current: QUIC,
-			}, nil
-		}
 		return &staticProtocolSelector{
 			current: HTTP2,
 		}, nil
 	}
+	if warpRoutingEnabled {
+		if protocolFlag == H2mux.String() || fetchedProtocol == H2mux {
+			log.Warn().Msg("Warp routing is not supported in h2mux protocol. Upgrading to http2 to allow it.")
+			protocolFlag = HTTP2.String()
+			fetchedProtocol = HTTP2Warp
+		}
+		return selectWarpRoutingProtocols(protocolFlag, fetchFunc, ttl, log, threshold, fetchedProtocol)
+	}
 
+	return selectNamedTunnelProtocols(protocolFlag, fetchFunc, ttl, log, threshold, fetchedProtocol)
+}
+
+func selectNamedTunnelProtocols(
+	protocolFlag string,
+	fetchFunc PercentageFetcher,
+	ttl time.Duration,
+	log *zerolog.Logger,
+	threshold int32,
+	protocol Protocol,
+) (ProtocolSelector, error) {
 	if protocolFlag == H2mux.String() {
 		return &staticProtocolSelector{
 			current: H2mux,
@@ -202,31 +244,41 @@ func NewProtocolSelector(
 	}
 
 	if protocolFlag == QUIC.String() {
-		return newAutoProtocolSelector(QUIC, explicitHTTP2FallbackThreshold, fetchFunc, ttl, log), nil
+		return newAutoProtocolSelector(QUIC, []Protocol{QUIC, HTTP2, H2mux}, explicitHTTP2FallbackThreshold, fetchFunc, ttl, log), nil
 	}
 
-	http2Percentage, err := fetchFunc()
-	if err != nil {
-		log.Err(err).Msg("Unable to lookup protocol. Defaulting to `http2`. If this fails, you can set `--protocol h2mux` in your cloudflared command.")
-		return &staticProtocolSelector{
-			current: HTTP2,
-		}, nil
-	}
 	if protocolFlag == HTTP2.String() {
-		if http2Percentage < 0 {
+		return newAutoProtocolSelector(HTTP2, []Protocol{HTTP2, H2mux}, explicitHTTP2FallbackThreshold, fetchFunc, ttl, log), nil
-			return newAutoProtocolSelector(H2mux, explicitHTTP2FallbackThreshold, fetchFunc, ttl, log), nil
-		}
-		return newAutoProtocolSelector(HTTP2, explicitHTTP2FallbackThreshold, fetchFunc, ttl, log), nil
 	}
 
 	if protocolFlag != autoSelectFlag {
 		return nil, fmt.Errorf("Unknown protocol %s, %s", protocolFlag, AvailableProtocolFlagMessage)
 	}
-	threshold := switchThreshold(namedTunnel.Credentials.AccountTag)
+
-	if threshold < http2Percentage {
+	return newAutoProtocolSelector(protocol, []Protocol{QUIC, HTTP2, H2mux}, threshold, fetchFunc, ttl, log), nil
-		return newAutoProtocolSelector(HTTP2, threshold, fetchFunc, ttl, log), nil
+}
+
+func selectWarpRoutingProtocols(
+	protocolFlag string,
+	fetchFunc PercentageFetcher,
+	ttl time.Duration,
+	log *zerolog.Logger,
+	threshold int32,
+	protocol Protocol,
+) (ProtocolSelector, error) {
+	if protocolFlag == QUIC.String() {
+		return newAutoProtocolSelector(QUICWarp, []Protocol{QUICWarp, HTTP2Warp}, explicitHTTP2FallbackThreshold, fetchFunc, ttl, log), nil
 	}
-	return newAutoProtocolSelector(H2mux, threshold, fetchFunc, ttl, log), nil
+
+	if protocolFlag == HTTP2.String() {
+		return newAutoProtocolSelector(HTTP2Warp, []Protocol{HTTP2Warp}, explicitHTTP2FallbackThreshold, fetchFunc, ttl, log), nil
+	}
+
+	if protocolFlag != autoSelectFlag {
+		return nil, fmt.Errorf("Unknown protocol %s, %s", protocolFlag, AvailableProtocolFlagMessage)
+	}
+
+	return newAutoProtocolSelector(protocol, []Protocol{QUICWarp, HTTP2Warp}, threshold, fetchFunc, ttl, log), nil
 }
 
 func switchThreshold(accountTag string) int32 {

connection/protocol_test.go

@@ -6,6 +6,8 @@ import (
 	"time"
 
 	"github.com/stretchr/testify/assert"
+
+	"github.com/cloudflare/cloudflared/edgediscovery"
 )
 
 const (
@@ -21,29 +23,23 @@ var (
 	}
 )
 
-func mockFetcher(percentage int32) PercentageFetcher {
+func mockFetcher(getError bool, protocolPercent ...edgediscovery.ProtocolPercent) PercentageFetcher {
-	return func() (int32, error) {
+	return func() (edgediscovery.ProtocolPercents, error) {
-		return percentage, nil
+		if getError {
+			return nil, fmt.Errorf("failed to fetch precentage")
 		}
-}
+		return protocolPercent, nil
-
-func mockFetcherWithError() PercentageFetcher {
-	return func() (int32, error) {
-		return 0, fmt.Errorf("failed to fetch precentage")
 	}
 }
 
 type dynamicMockFetcher struct {
-	percentage int32
+	protocolPercents edgediscovery.ProtocolPercents
 	err              error
 }
 
 func (dmf *dynamicMockFetcher) fetch() PercentageFetcher {
-	return func() (int32, error) {
+	return func() (edgediscovery.ProtocolPercents, error) {
-		if dmf.err != nil {
+		return dmf.protocolPercents, dmf.err
-			return 0, dmf.err
-		}
-		return dmf.percentage, nil
 	}
 }
 
@@ -69,6 +65,7 @@ func TestNewProtocolSelector(t *testing.T) {
 			name:              "named tunnel over h2mux",
 			protocol:          "h2mux",
 			expectedProtocol:  H2mux,
+			fetchFunc:         func() (edgediscovery.ProtocolPercents, error) { return nil, nil },
 			namedTunnelConfig: testNamedTunnelConfig,
 		},
 		{
@@ -77,28 +74,38 @@ func TestNewProtocolSelector(t *testing.T) {
 			expectedProtocol:  HTTP2,
 			hasFallback:       true,
 			expectedFallback:  H2mux,
-			fetchFunc:         mockFetcher(0),
+			fetchFunc:         mockFetcher(false, edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: 0}),
 			namedTunnelConfig: testNamedTunnelConfig,
 		},
 		{
 			name:              "named tunnel http2 disabled",
 			protocol:          "http2",
 			expectedProtocol:  H2mux,
-			fetchFunc:         mockFetcher(-1),
+			fetchFunc:         mockFetcher(false, edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: -1}),
+			namedTunnelConfig: testNamedTunnelConfig,
+		},
+		{
+			name:             "named tunnel quic disabled",
+			protocol:         "quic",
+			expectedProtocol: HTTP2,
+			// Hasfallback true is because if http2 fails, then we further fallback to h2mux.
+			hasFallback:       true,
+			expectedFallback:  H2mux,
+			fetchFunc:         mockFetcher(false, edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: 100}, edgediscovery.ProtocolPercent{Protocol: "quic", Percentage: -1}),
 			namedTunnelConfig: testNamedTunnelConfig,
 		},
 		{
 			name:              "named tunnel auto all http2 disabled",
 			protocol:          "auto",
 			expectedProtocol:  H2mux,
-			fetchFunc:         mockFetcher(-1),
+			fetchFunc:         mockFetcher(false, edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: -1}),
 			namedTunnelConfig: testNamedTunnelConfig,
 		},
 		{
 			name:              "named tunnel auto to h2mux",
 			protocol:          "auto",
 			expectedProtocol:  H2mux,
-			fetchFunc:         mockFetcher(0),
+			fetchFunc:         mockFetcher(false, edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: 0}),
 			namedTunnelConfig: testNamedTunnelConfig,
 		},
 		{
@@ -107,36 +114,71 @@ func TestNewProtocolSelector(t *testing.T) {
 			expectedProtocol:  HTTP2,
 			hasFallback:       true,
 			expectedFallback:  H2mux,
-			fetchFunc:         mockFetcher(100),
+			fetchFunc:         mockFetcher(false, edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: 100}),
+			namedTunnelConfig: testNamedTunnelConfig,
+		},
+		{
+			name:              "named tunnel auto to quic",
+			protocol:          "auto",
+			expectedProtocol:  QUIC,
+			hasFallback:       true,
+			expectedFallback:  HTTP2,
+			fetchFunc:         mockFetcher(false, edgediscovery.ProtocolPercent{Protocol: "quic", Percentage: 100}),
 			namedTunnelConfig: testNamedTunnelConfig,
 		},
 		{
 			name:               "warp routing requesting h2mux",
 			protocol:           "h2mux",
-			expectedProtocol:   HTTP2,
+			expectedProtocol:   HTTP2Warp,
 			hasFallback:        false,
-			expectedFallback:   H2mux,
+			fetchFunc:          mockFetcher(false, edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: 100}),
-			fetchFunc:          mockFetcher(100),
+			warpRoutingEnabled: true,
+			namedTunnelConfig:  testNamedTunnelConfig,
+		},
+		{
+			name:               "warp routing requesting h2mux picks HTTP2 even if http2 percent is -1",
+			protocol:           "h2mux",
+			expectedProtocol:   HTTP2Warp,
+			hasFallback:        false,
+			fetchFunc:          mockFetcher(false, edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: -1}),
 			warpRoutingEnabled: true,
 			namedTunnelConfig:  testNamedTunnelConfig,
 		},
 		{
 			name:               "warp routing http2",
 			protocol:           "http2",
-			expectedProtocol:   HTTP2,
+			expectedProtocol:   HTTP2Warp,
 			hasFallback:        false,
-			expectedFallback:   H2mux,
+			fetchFunc:          mockFetcher(false, edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: 100}),
-			fetchFunc:          mockFetcher(100),
+			warpRoutingEnabled: true,
+			namedTunnelConfig:  testNamedTunnelConfig,
+		},
+		{
+			name:               "warp routing quic",
+			protocol:           "quic",
+			expectedProtocol:   QUICWarp,
+			hasFallback:        true,
+			expectedFallback:   HTTP2Warp,
+			fetchFunc:          mockFetcher(false, edgediscovery.ProtocolPercent{Protocol: "quic", Percentage: 100}),
 			warpRoutingEnabled: true,
 			namedTunnelConfig:  testNamedTunnelConfig,
 		},
 		{
 			name:               "warp routing auto",
 			protocol:           "auto",
-			expectedProtocol:   HTTP2,
+			expectedProtocol:   HTTP2Warp,
 			hasFallback:        false,
-			expectedFallback:   H2mux,
+			fetchFunc:          mockFetcher(false, edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: 100}),
-			fetchFunc:          mockFetcher(100),
+			warpRoutingEnabled: true,
+			namedTunnelConfig:  testNamedTunnelConfig,
+		},
+		{
+			name:               "warp routing auto- quic",
+			protocol:           "auto",
+			expectedProtocol:   QUICWarp,
+			hasFallback:        true,
+			expectedFallback:   HTTP2Warp,
+			fetchFunc:          mockFetcher(false, edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: 100}, edgediscovery.ProtocolPercent{Protocol: "quic", Percentage: 100}),
 			warpRoutingEnabled: true,
 			namedTunnelConfig:  testNamedTunnelConfig,
 		},
@@ -149,14 +191,14 @@ func TestNewProtocolSelector(t *testing.T) {
 		{
 			name:              "named tunnel unknown protocol",
 			protocol:          "unknown",
-			fetchFunc:         mockFetcher(100),
+			fetchFunc:         mockFetcher(false, edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: 100}),
 			namedTunnelConfig: testNamedTunnelConfig,
 			wantErr:           true,
 		},
 		{
 			name:              "named tunnel fetch error",
-			protocol:          "unknown",
+			protocol:          "auto",
-			fetchFunc:         mockFetcherWithError(),
+			fetchFunc:         mockFetcher(true),
 			namedTunnelConfig: testNamedTunnelConfig,
 			expectedProtocol:  HTTP2,
 			wantErr:           false,
@@ -164,6 +206,7 @@ func TestNewProtocolSelector(t *testing.T) {
 	}
 
 	for _, test := range tests {
+		t.Run(test.name, func(t *testing.T) {
 			selector, err := NewProtocolSelector(test.protocol, test.warpRoutingEnabled, test.namedTunnelConfig, test.fetchFunc, testNoTTL, &log)
 			if test.wantErr {
 				assert.Error(t, err, fmt.Sprintf("test %s failed", test.name))
@@ -176,6 +219,7 @@ func TestNewProtocolSelector(t *testing.T) {
 					assert.Equal(t, test.expectedFallback, fallback, fmt.Sprintf("test %s failed", test.name))
 				}
 			}
+		})
 	}
 }
 
@@ -185,27 +229,27 @@ func TestAutoProtocolSelectorRefresh(t *testing.T) {
 	assert.NoError(t, err)
 	assert.Equal(t, H2mux, selector.Current())
 
-	fetcher.percentage = 100
+	fetcher.protocolPercents = edgediscovery.ProtocolPercents{edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: 100}}
 	assert.Equal(t, HTTP2, selector.Current())
 
-	fetcher.percentage = 0
+	fetcher.protocolPercents = edgediscovery.ProtocolPercents{edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: 0}}
 	assert.Equal(t, H2mux, selector.Current())
 
-	fetcher.percentage = 100
+	fetcher.protocolPercents = edgediscovery.ProtocolPercents{edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: 100}}
 	assert.Equal(t, HTTP2, selector.Current())
 
 	fetcher.err = fmt.Errorf("failed to fetch")
 	assert.Equal(t, HTTP2, selector.Current())
 
-	fetcher.percentage = -1
+	fetcher.protocolPercents = edgediscovery.ProtocolPercents{edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: -1}}
 	fetcher.err = nil
 	assert.Equal(t, H2mux, selector.Current())
 
-	fetcher.percentage = 0
+	fetcher.protocolPercents = edgediscovery.ProtocolPercents{edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: 0}}
 	assert.Equal(t, H2mux, selector.Current())
 
-	fetcher.percentage = 100
+	fetcher.protocolPercents = edgediscovery.ProtocolPercents{edgediscovery.ProtocolPercent{Protocol: "quic", Percentage: 100}}
-	assert.Equal(t, HTTP2, selector.Current())
+	assert.Equal(t, QUIC, selector.Current())
 }
 
 func TestHTTP2ProtocolSelectorRefresh(t *testing.T) {
@@ -214,35 +258,36 @@ func TestHTTP2ProtocolSelectorRefresh(t *testing.T) {
 	assert.NoError(t, err)
 	assert.Equal(t, HTTP2, selector.Current())
 
-	fetcher.percentage = 100
+	fetcher.protocolPercents = edgediscovery.ProtocolPercents{edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: 100}}
 	assert.Equal(t, HTTP2, selector.Current())
 
-	fetcher.percentage = 0
+	fetcher.protocolPercents = edgediscovery.ProtocolPercents{edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: 0}}
 	assert.Equal(t, HTTP2, selector.Current())
 
 	fetcher.err = fmt.Errorf("failed to fetch")
 	assert.Equal(t, HTTP2, selector.Current())
 
-	fetcher.percentage = -1
+	fetcher.protocolPercents = edgediscovery.ProtocolPercents{edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: -1}}
 	fetcher.err = nil
 	assert.Equal(t, H2mux, selector.Current())
 
-	fetcher.percentage = 0
+	fetcher.protocolPercents = edgediscovery.ProtocolPercents{edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: 0}}
 	assert.Equal(t, HTTP2, selector.Current())
 
-	fetcher.percentage = 100
+	fetcher.protocolPercents = edgediscovery.ProtocolPercents{edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: 100}}
 	assert.Equal(t, HTTP2, selector.Current())
 
-	fetcher.percentage = -1
+	fetcher.protocolPercents = edgediscovery.ProtocolPercents{edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: -1}}
 	assert.Equal(t, H2mux, selector.Current())
 }
 
 func TestProtocolSelectorRefreshTTL(t *testing.T) {
-	fetcher := dynamicMockFetcher{percentage: 100}
+	fetcher := dynamicMockFetcher{}
+	fetcher.protocolPercents = edgediscovery.ProtocolPercents{edgediscovery.ProtocolPercent{Protocol: "quic", Percentage: 100}}
 	selector, err := NewProtocolSelector("auto", noWarpRoutingEnabled, testNamedTunnelConfig, fetcher.fetch(), time.Hour, &log)
 	assert.NoError(t, err)
-	assert.Equal(t, HTTP2, selector.Current())
+	assert.Equal(t, QUIC, selector.Current())
 
-	fetcher.percentage = 0
+	fetcher.protocolPercents = edgediscovery.ProtocolPercents{edgediscovery.ProtocolPercent{Protocol: "quic", Percentage: 0}}
-	assert.Equal(t, HTTP2, selector.Current())
+	assert.Equal(t, QUIC, selector.Current())
 }

edgediscovery/protocol.go

@@ -1,45 +1,50 @@
 package edgediscovery
 
 import (
+	"encoding/json"
 	"fmt"
 	"net"
-	"strconv"
 	"strings"
 )
 
 const (
-	protocolRecord = "protocol.argotunnel.com"
+	protocolRecord = "protocol-v2.argotunnel.com"
 )
 
 var (
 	errNoProtocolRecord = fmt.Errorf("No TXT record found for %s to determine connection protocol", protocolRecord)
 )
 
-func HTTP2Percentage() (int32, error) {
+// ProtocolPercent represents a single Protocol Percentage combination.
+type ProtocolPercent struct {
+	Protocol   string `json:"protocol"`
+	Percentage int32  `json:"percentage"`
+}
+
+// ProtocolPercents represents the preferred distribution ratio of protocols when protocol isn't specified.
+type ProtocolPercents []ProtocolPercent
+
+// GetPercentage returns the threshold percentage of a single protocol.
+func (p ProtocolPercents) GetPercentage(protocol string) int32 {
+	for _, protocolPercent := range p {
+		if strings.ToLower(protocolPercent.Protocol) == strings.ToLower(protocol) {
+			return protocolPercent.Percentage
+		}
+	}
+	return 0
+}
+
+// ProtocolPercentage returns the ratio of protocols and a specification ratio for their selection.
+func ProtocolPercentage() (ProtocolPercents, error) {
 	records, err := net.LookupTXT(protocolRecord)
 	if err != nil {
-		return 0, err
+		return nil, err
 	}
 	if len(records) == 0 {
-		return 0, errNoProtocolRecord
+		return nil, errNoProtocolRecord
 	}
-	return parseHTTP2Precentage(records[0])
-}
-
-// The record looks like http2=percentage
-func parseHTTP2Precentage(record string) (int32, error) {
-	const key = "http2"
-	slices := strings.Split(record, "=")
-	if len(slices) != 2 {
-		return 0, fmt.Errorf("Malformed TXT record %s, expect http2=percentage", record)
-	}
-	if slices[0] != key {
-		return 0, fmt.Errorf("Incorrect key %s, expect %s", slices[0], key)
-	}
-	percentage, err := strconv.ParseInt(slices[1], 10, 32)
-	if err != nil {
-		return 0, err
-	}
-	return int32(percentage), nil
 
+	var protocolsWithPercent ProtocolPercents
+	err = json.Unmarshal([]byte(records[0]), &protocolsWithPercent)
+	return protocolsWithPercent, err
 }

edgediscovery/protocol_test.go

@@ -6,75 +6,7 @@ import (
 	"github.com/stretchr/testify/assert"
 )
 
-func TestHTTP2Percentage(t *testing.T) {
+func TestProtocolPercentage(t *testing.T) {
-	_, err := HTTP2Percentage()
+	_, err := ProtocolPercentage()
 	assert.NoError(t, err)
 }
-
-func TestParseHTTP2Precentage(t *testing.T) {
-	tests := []struct {
-		record     string
-		percentage int32
-		wantErr    bool
-	}{
-		{
-			record:     "http2=-1",
-			percentage: -1,
-			wantErr:    false,
-		},
-		{
-			record:     "http2=0",
-			percentage: 0,
-			wantErr:    false,
-		},
-		{
-			record:     "http2=50",
-			percentage: 50,
-			wantErr:    false,
-		},
-		{
-			record:     "http2=100",
-			percentage: 100,
-			wantErr:    false,
-		},
-		{
-			record:     "http2=1000",
-			percentage: 1000,
-			wantErr:    false,
-		},
-		{
-			record:  "http2=10.5",
-			wantErr: true,
-		},
-		{
-			record:  "http2=10 h2mux=90",
-			wantErr: true,
-		},
-		{
-			record:  "http2=ten",
-			wantErr: true,
-		},
-
-		{
-			record:  "h2mux=100",
-			wantErr: true,
-		},
-		{
-			record:  "http2",
-			wantErr: true,
-		},
-		{
-			record:  "http2=",
-			wantErr: true,
-		},
-	}
-
-	for _, test := range tests {
-		p, err := parseHTTP2Precentage(test.record)
-		if test.wantErr {
-			assert.Error(t, err)
-		} else {
-			assert.Equal(t, test.percentage, p)
-		}
-	}
-}

origin/tunnel_test.go

@@ -8,20 +8,18 @@ import (
 	"github.com/stretchr/testify/assert"
 
 	"github.com/cloudflare/cloudflared/connection"
+	"github.com/cloudflare/cloudflared/edgediscovery"
 	"github.com/cloudflare/cloudflared/retry"
 )
 
 type dynamicMockFetcher struct {
-	percentage int32
+	protocolPercents edgediscovery.ProtocolPercents
 	err              error
 }
 
 func (dmf *dynamicMockFetcher) fetch() connection.PercentageFetcher {
-	return func() (int32, error) {
+	return func() (edgediscovery.ProtocolPercents, error) {
-		if dmf.err != nil {
+		return dmf.protocolPercents, dmf.err
-			return 0, dmf.err
-		}
-		return dmf.percentage, nil
 	}
 }
 
@@ -39,7 +37,7 @@ func TestWaitForBackoffFallback(t *testing.T) {
 		},
 	}
 	mockFetcher := dynamicMockFetcher{
-		percentage: 0,
+		protocolPercents: edgediscovery.ProtocolPercents{edgediscovery.ProtocolPercent{Protocol: "http2", Percentage: 100}},
 	}
 	warpRoutingEnabled := false
 	protocolSelector, err := connection.NewProtocolSelector(