TUN-3458: Upgrade to http2 when available, fallback to h2mux when we reach max retries

origin/tunnel_test.go

@@ -0,0 +1,90 @@
+package origin
+
+import (
+	"context"
+	"fmt"
+	"testing"
+	"time"
+
+	"github.com/cloudflare/cloudflared/connection"
+	"github.com/cloudflare/cloudflared/logger"
+	"github.com/cloudflare/cloudflared/tunnelrpc/pogs"
+	"github.com/stretchr/testify/assert"
+)
+
+type dynamicMockFetcher struct {
+	percentage int32
+	err        error
+}
+
+func (dmf *dynamicMockFetcher) fetch() connection.PercentageFetcher {
+	return func() (int32, error) {
+		if dmf.err != nil {
+			return 0, dmf.err
+		}
+		return dmf.percentage, nil
+	}
+}
+func TestWaitForBackoffFallback(t *testing.T) {
+	maxRetries := uint(3)
+	backoff := BackoffHandler{
+		MaxRetries: maxRetries,
+		BaseTime:   time.Millisecond * 10,
+	}
+	ctx := context.Background()
+	logger, err := logger.New()
+	assert.NoError(t, err)
+	resolveTTL := time.Duration(0)
+	namedTunnel := &connection.NamedTunnelConfig{
+		Auth: pogs.TunnelAuth{
+			AccountTag: "test-account",
+		},
+	}
+	mockFetcher := dynamicMockFetcher{
+		percentage: 0,
+	}
+	protocolSelector, err := connection.NewProtocolSelector(connection.HTTP2.String(), namedTunnel, mockFetcher.fetch(), resolveTTL, logger)
+	assert.NoError(t, err)
+	config := &TunnelConfig{
+		Logger:           logger,
+		ProtocolSelector: protocolSelector,
+	}
+	connIndex := uint8(1)
+
+	initProtocol := protocolSelector.Current()
+	assert.Equal(t, connection.HTTP2, initProtocol)
+
+	protocallFallback := &protocallFallback{
+		backoff,
+		initProtocol,
+		false,
+	}
+
+	// Retry #0 and #1. At retry #2, we switch protocol, so the fallback loop has one more retry than this
+	for i := 0; i < int(maxRetries-1); i++ {
+		err := waitForBackoff(ctx, protocallFallback, config, connIndex, fmt.Errorf("Some error"))
+		assert.NoError(t, err)
+		assert.Equal(t, initProtocol, protocallFallback.protocol)
+	}
+
+	// Retry fallback protocol
+	for i := 0; i < int(maxRetries); i++ {
+		err := waitForBackoff(ctx, protocallFallback, config, connIndex, fmt.Errorf("Some error"))
+		assert.NoError(t, err)
+		fallback, ok := protocolSelector.Fallback()
+		assert.True(t, ok)
+		assert.Equal(t, fallback, protocallFallback.protocol)
+	}
+
+	currentGlobalProtocol := protocolSelector.Current()
+	assert.Equal(t, initProtocol, currentGlobalProtocol)
+
+	// No protocol to fallback, return error
+	err = waitForBackoff(ctx, protocallFallback, config, connIndex, fmt.Errorf("Some error"))
+	assert.Error(t, err)
+
+	protocallFallback.reset()
+	err = waitForBackoff(ctx, protocallFallback, config, connIndex, fmt.Errorf("New error"))
+	assert.NoError(t, err)
+	assert.Equal(t, initProtocol, protocallFallback.protocol)
+}