update OpenTelemetry dependencies and grpc

This update dropped the otelgrpc → cloud.google.com/go/compute dependency,
among others. This dropped out because genproto cleaned up it's dependencies
on google cloud libraries, and otel updated - details in #113366.

Signed-off-by: Davanum Srinivas <davanum@gmail.com>
Co-Authored-By: David Ashpole <dashpole@google.com>

vendor/google.golang.org/grpc/internal/resolver/dns/dns_resolver.go

@@ -23,8 +23,8 @@ package dns
 import (
 	"context"
 	"encoding/json"
-	"errors"
 	"fmt"
+	"math/rand"
 	"net"
 	"os"
 	"strconv"
@@ -36,26 +36,37 @@ import (
 	"google.golang.org/grpc/grpclog"
 	"google.golang.org/grpc/internal/backoff"
 	"google.golang.org/grpc/internal/envconfig"
-	"google.golang.org/grpc/internal/grpcrand"
+	"google.golang.org/grpc/internal/resolver/dns/internal"
 	"google.golang.org/grpc/resolver"
 	"google.golang.org/grpc/serviceconfig"
 )
 
-// EnableSRVLookups controls whether the DNS resolver attempts to fetch gRPCLB
-// addresses from SRV records.  Must not be changed after init time.
-var EnableSRVLookups = false
-
-var logger = grpclog.Component("dns")
-
-// Globals to stub out in tests. TODO: Perhaps these two can be combined into a
-// single variable for testing the resolver?
 var (
-	newTimer           = time.NewTimer
-	newTimerDNSResRate = time.NewTimer
+	// EnableSRVLookups controls whether the DNS resolver attempts to fetch gRPCLB
+	// addresses from SRV records.  Must not be changed after init time.
+	EnableSRVLookups = false
+
+	// MinResolutionInterval is the minimum interval at which re-resolutions are
+	// allowed. This helps to prevent excessive re-resolution.
+	MinResolutionInterval = 30 * time.Second
+
+	// ResolvingTimeout specifies the maximum duration for a DNS resolution request.
+	// If the timeout expires before a response is received, the request will be canceled.
+	//
+	// It is recommended to set this value at application startup. Avoid modifying this variable
+	// after initialization as it's not thread-safe for concurrent modification.
+	ResolvingTimeout = 30 * time.Second
+
+	logger = grpclog.Component("dns")
 )
 
 func init() {
 	resolver.Register(NewBuilder())
+	internal.TimeAfterFunc = time.After
+	internal.TimeNowFunc = time.Now
+	internal.TimeUntilFunc = time.Until
+	internal.NewNetResolver = newNetResolver
+	internal.AddressDialer = addressDialer
 }
 
 const (
@@ -70,23 +81,6 @@ const (
 	txtAttribute = "grpc_config="
 )
 
-var (
-	errMissingAddr = errors.New("dns resolver: missing address")
-
-	// Addresses ending with a colon that is supposed to be the separator
-	// between host and port is not allowed.  E.g. "::" is a valid address as
-	// it is an IPv6 address (host only) and "[::]:" is invalid as it ends with
-	// a colon as the host and port separator
-	errEndsWithColon = errors.New("dns resolver: missing port after port-separator colon")
-)
-
-var (
-	defaultResolver netResolver = net.DefaultResolver
-	// To prevent excessive re-resolution, we enforce a rate limit on DNS
-	// resolution requests.
-	minDNSResRate = 30 * time.Second
-)
-
 var addressDialer = func(address string) func(context.Context, string, string) (net.Conn, error) {
 	return func(ctx context.Context, network, _ string) (net.Conn, error) {
 		var dialer net.Dialer
@@ -94,7 +88,11 @@ var addressDialer = func(address string) func(context.Context, string, string) (
 	}
 }
 
-var newNetResolver = func(authority string) (netResolver, error) {
+var newNetResolver = func(authority string) (internal.NetResolver, error) {
+	if authority == "" {
+		return net.DefaultResolver, nil
+	}
+
 	host, port, err := parseTarget(authority, defaultDNSSvrPort)
 	if err != nil {
 		return nil, err
@@ -104,7 +102,7 @@ var newNetResolver = func(authority string) (netResolver, error) {
 
 	return &net.Resolver{
 		PreferGo: true,
-		Dial:     addressDialer(authorityWithPort),
+		Dial:     internal.AddressDialer(authorityWithPort),
 	}, nil
 }
 
@@ -142,13 +140,9 @@ func (b *dnsBuilder) Build(target resolver.Target, cc resolver.ClientConn, opts
 		disableServiceConfig: opts.DisableServiceConfig,
 	}
 
-	if target.URL.Host == "" {
-		d.resolver = defaultResolver
-	} else {
-		d.resolver, err = newNetResolver(target.URL.Host)
-		if err != nil {
-			return nil, err
-		}
+	d.resolver, err = internal.NewNetResolver(target.URL.Host)
+	if err != nil {
+		return nil, err
 	}
 
 	d.wg.Add(1)
@@ -161,12 +155,6 @@ func (b *dnsBuilder) Scheme() string {
 	return "dns"
 }
 
-type netResolver interface {
-	LookupHost(ctx context.Context, host string) (addrs []string, err error)
-	LookupSRV(ctx context.Context, service, proto, name string) (cname string, addrs []*net.SRV, err error)
-	LookupTXT(ctx context.Context, name string) (txts []string, err error)
-}
-
 // deadResolver is a resolver that does nothing.
 type deadResolver struct{}
 
@@ -178,7 +166,7 @@ func (deadResolver) Close() {}
 type dnsResolver struct {
 	host     string
 	port     string
-	resolver netResolver
+	resolver internal.NetResolver
 	ctx      context.Context
 	cancel   context.CancelFunc
 	cc       resolver.ClientConn
@@ -223,45 +211,43 @@ func (d *dnsResolver) watcher() {
 			err = d.cc.UpdateState(*state)
 		}
 
-		var timer *time.Timer
+		var nextResolutionTime time.Time
 		if err == nil {
 			// Success resolving, wait for the next ResolveNow. However, also wait 30
 			// seconds at the very least to prevent constantly re-resolving.
 			backoffIndex = 1
-			timer = newTimerDNSResRate(minDNSResRate)
+			nextResolutionTime = internal.TimeNowFunc().Add(MinResolutionInterval)
 			select {
 			case <-d.ctx.Done():
-				timer.Stop()
 				return
 			case <-d.rn:
 			}
 		} else {
 			// Poll on an error found in DNS Resolver or an error received from
 			// ClientConn.
-			timer = newTimer(backoff.DefaultExponential.Backoff(backoffIndex))
+			nextResolutionTime = internal.TimeNowFunc().Add(backoff.DefaultExponential.Backoff(backoffIndex))
 			backoffIndex++
 		}
 		select {
 		case <-d.ctx.Done():
-			timer.Stop()
 			return
-		case <-timer.C:
+		case <-internal.TimeAfterFunc(internal.TimeUntilFunc(nextResolutionTime)):
 		}
 	}
 }
 
-func (d *dnsResolver) lookupSRV() ([]resolver.Address, error) {
+func (d *dnsResolver) lookupSRV(ctx context.Context) ([]resolver.Address, error) {
 	if !EnableSRVLookups {
 		return nil, nil
 	}
 	var newAddrs []resolver.Address
-	_, srvs, err := d.resolver.LookupSRV(d.ctx, "grpclb", "tcp", d.host)
+	_, srvs, err := d.resolver.LookupSRV(ctx, "grpclb", "tcp", d.host)
 	if err != nil {
 		err = handleDNSError(err, "SRV") // may become nil
 		return nil, err
 	}
 	for _, s := range srvs {
-		lbAddrs, err := d.resolver.LookupHost(d.ctx, s.Target)
+		lbAddrs, err := d.resolver.LookupHost(ctx, s.Target)
 		if err != nil {
 			err = handleDNSError(err, "A") // may become nil
 			if err == nil {
@@ -298,8 +284,8 @@ func handleDNSError(err error, lookupType string) error {
 	return err
 }
 
-func (d *dnsResolver) lookupTXT() *serviceconfig.ParseResult {
-	ss, err := d.resolver.LookupTXT(d.ctx, txtPrefix+d.host)
+func (d *dnsResolver) lookupTXT(ctx context.Context) *serviceconfig.ParseResult {
+	ss, err := d.resolver.LookupTXT(ctx, txtPrefix+d.host)
 	if err != nil {
 		if envconfig.TXTErrIgnore {
 			return nil
@@ -326,8 +312,8 @@ func (d *dnsResolver) lookupTXT() *serviceconfig.ParseResult {
 	return d.cc.ParseServiceConfig(sc)
 }
 
-func (d *dnsResolver) lookupHost() ([]resolver.Address, error) {
-	addrs, err := d.resolver.LookupHost(d.ctx, d.host)
+func (d *dnsResolver) lookupHost(ctx context.Context) ([]resolver.Address, error) {
+	addrs, err := d.resolver.LookupHost(ctx, d.host)
 	if err != nil {
 		err = handleDNSError(err, "A")
 		return nil, err
@@ -345,8 +331,10 @@ func (d *dnsResolver) lookupHost() ([]resolver.Address, error) {
 }
 
 func (d *dnsResolver) lookup() (*resolver.State, error) {
-	srv, srvErr := d.lookupSRV()
-	addrs, hostErr := d.lookupHost()
+	ctx, cancel := context.WithTimeout(d.ctx, ResolvingTimeout)
+	defer cancel()
+	srv, srvErr := d.lookupSRV(ctx)
+	addrs, hostErr := d.lookupHost(ctx)
 	if hostErr != nil && (srvErr != nil || len(srv) == 0) {
 		return nil, hostErr
 	}
@@ -356,7 +344,7 @@ func (d *dnsResolver) lookup() (*resolver.State, error) {
 		state = grpclbstate.Set(state, &grpclbstate.State{BalancerAddresses: srv})
 	}
 	if !d.disableServiceConfig {
-		state.ServiceConfig = d.lookupTXT()
+		state.ServiceConfig = d.lookupTXT(ctx)
 	}
 	return &state, nil
 }
@@ -387,7 +375,7 @@ func formatIP(addr string) (addrIP string, ok bool) {
 // target: ":80" defaultPort: "443" returns host: "localhost", port: "80"
 func parseTarget(target, defaultPort string) (host, port string, err error) {
 	if target == "" {
-		return "", "", errMissingAddr
+		return "", "", internal.ErrMissingAddr
 	}
 	if ip := net.ParseIP(target); ip != nil {
 		// target is an IPv4 or IPv6(without brackets) address
@@ -397,7 +385,7 @@ func parseTarget(target, defaultPort string) (host, port string, err error) {
 		if port == "" {
 			// If the port field is empty (target ends with colon), e.g. "[::1]:",
 			// this is an error.
-			return "", "", errEndsWithColon
+			return "", "", internal.ErrEndsWithColon
 		}
 		// target has port, i.e ipv4-host:port, [ipv6-host]:port, host-name:port
 		if host == "" {
@@ -437,7 +425,7 @@ func chosenByPercentage(a *int) bool {
 	if a == nil {
 		return true
 	}
-	return grpcrand.Intn(100)+1 <= *a
+	return rand.Intn(100)+1 <= *a
 }
 
 func canaryingSC(js string) string {

vendor/google.golang.org/grpc/internal/resolver/dns/internal/internal.go

@@ -0,0 +1,77 @@
+/*
+ *
+ * Copyright 2023 gRPC authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ *
+ */
+
+// Package internal contains functionality internal to the dns resolver package.
+package internal
+
+import (
+	"context"
+	"errors"
+	"net"
+	"time"
+)
+
+// NetResolver groups the methods on net.Resolver that are used by the DNS
+// resolver implementation. This allows the default net.Resolver instance to be
+// overridden from tests.
+type NetResolver interface {
+	LookupHost(ctx context.Context, host string) (addrs []string, err error)
+	LookupSRV(ctx context.Context, service, proto, name string) (cname string, addrs []*net.SRV, err error)
+	LookupTXT(ctx context.Context, name string) (txts []string, err error)
+}
+
+var (
+	// ErrMissingAddr is the error returned when building a DNS resolver when
+	// the provided target name is empty.
+	ErrMissingAddr = errors.New("dns resolver: missing address")
+
+	// ErrEndsWithColon is the error returned when building a DNS resolver when
+	// the provided target name ends with a colon that is supposed to be the
+	// separator between host and port.  E.g. "::" is a valid address as it is
+	// an IPv6 address (host only) and "[::]:" is invalid as it ends with a
+	// colon as the host and port separator
+	ErrEndsWithColon = errors.New("dns resolver: missing port after port-separator colon")
+)
+
+// The following vars are overridden from tests.
+var (
+	// TimeAfterFunc is used by the DNS resolver to wait for the given duration
+	// to elapse. In non-test code, this is implemented by time.After. In test
+	// code, this can be used to control the amount of time the resolver is
+	// blocked waiting for the duration to elapse.
+	TimeAfterFunc func(time.Duration) <-chan time.Time
+
+	// TimeNowFunc is used by the DNS resolver to get the current time.
+	// In non-test code, this is implemented by time.Now. In test code,
+	// this can be used to control the current time for the resolver.
+	TimeNowFunc func() time.Time
+
+	// TimeUntilFunc is used by the DNS resolver to calculate the remaining
+	// wait time for re-resolution. In non-test code, this is implemented by
+	// time.Until. In test code, this can be used to control the remaining
+	// time for resolver to wait for re-resolution.
+	TimeUntilFunc func(time.Time) time.Duration
+
+	// NewNetResolver returns the net.Resolver instance for the given target.
+	NewNetResolver func(string) (NetResolver, error)
+
+	// AddressDialer is the dialer used to dial the DNS server. It accepts the
+	// Host portion of the URL corresponding to the user's dial target and
+	// returns a dial function.
+	AddressDialer func(address string) func(context.Context, string, string) (net.Conn, error)
+)

vendor/google.golang.org/grpc/internal/resolver/unix/unix.go

@@ -61,6 +61,10 @@ func (b *builder) Scheme() string {
 	return b.scheme
 }
 
+func (b *builder) OverrideAuthority(resolver.Target) string {
+	return "localhost"
+}
+
 type nopResolver struct {
 }