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Diffstat (limited to 'vendor/google.golang.org/grpc/internal/resolver')
-rw-r--r--vendor/google.golang.org/grpc/internal/resolver/dns/dns_resolver.go74
1 files changed, 43 insertions, 31 deletions
diff --git a/vendor/google.golang.org/grpc/internal/resolver/dns/dns_resolver.go b/vendor/google.golang.org/grpc/internal/resolver/dns/dns_resolver.go
index 09a667f33..99e1e5b36 100644
--- a/vendor/google.golang.org/grpc/internal/resolver/dns/dns_resolver.go
+++ b/vendor/google.golang.org/grpc/internal/resolver/dns/dns_resolver.go
@@ -62,7 +62,8 @@ const (
defaultPort = "443"
defaultDNSSvrPort = "53"
golang = "GO"
- // txtPrefix is the prefix string to be prepended to the host name for txt record lookup.
+ // txtPrefix is the prefix string to be prepended to the host name for txt
+ // record lookup.
txtPrefix = "_grpc_config."
// In DNS, service config is encoded in a TXT record via the mechanism
// described in RFC-1464 using the attribute name grpc_config.
@@ -86,14 +87,14 @@ var (
minDNSResRate = 30 * time.Second
)
-var customAuthorityDialler = func(authority string) func(ctx context.Context, network, address string) (net.Conn, error) {
- return func(ctx context.Context, network, address string) (net.Conn, error) {
+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
- return dialer.DialContext(ctx, network, authority)
+ return dialer.DialContext(ctx, network, address)
}
}
-var customAuthorityResolver = func(authority string) (netResolver, error) {
+var newNetResolver = func(authority string) (netResolver, error) {
host, port, err := parseTarget(authority, defaultDNSSvrPort)
if err != nil {
return nil, err
@@ -103,7 +104,7 @@ var customAuthorityResolver = func(authority string) (netResolver, error) {
return &net.Resolver{
PreferGo: true,
- Dial: customAuthorityDialler(authorityWithPort),
+ Dial: addressDialer(authorityWithPort),
}, nil
}
@@ -114,7 +115,8 @@ func NewBuilder() resolver.Builder {
type dnsBuilder struct{}
-// Build creates and starts a DNS resolver that watches the name resolution of the target.
+// Build creates and starts a DNS resolver that watches the name resolution of
+// the target.
func (b *dnsBuilder) Build(target resolver.Target, cc resolver.ClientConn, opts resolver.BuildOptions) (resolver.Resolver, error) {
host, port, err := parseTarget(target.Endpoint(), defaultPort)
if err != nil {
@@ -143,7 +145,7 @@ func (b *dnsBuilder) Build(target resolver.Target, cc resolver.ClientConn, opts
if target.URL.Host == "" {
d.resolver = defaultResolver
} else {
- d.resolver, err = customAuthorityResolver(target.URL.Host)
+ d.resolver, err = newNetResolver(target.URL.Host)
if err != nil {
return nil, err
}
@@ -180,19 +182,22 @@ type dnsResolver struct {
ctx context.Context
cancel context.CancelFunc
cc resolver.ClientConn
- // rn channel is used by ResolveNow() to force an immediate resolution of the target.
+ // rn channel is used by ResolveNow() to force an immediate resolution of the
+ // target.
rn chan struct{}
- // wg is used to enforce Close() to return after the watcher() goroutine has finished.
- // Otherwise, data race will be possible. [Race Example] in dns_resolver_test we
- // replace the real lookup functions with mocked ones to facilitate testing.
- // If Close() doesn't wait for watcher() goroutine finishes, race detector sometimes
- // will warns lookup (READ the lookup function pointers) inside watcher() goroutine
- // has data race with replaceNetFunc (WRITE the lookup function pointers).
+ // wg is used to enforce Close() to return after the watcher() goroutine has
+ // finished. Otherwise, data race will be possible. [Race Example] in
+ // dns_resolver_test we replace the real lookup functions with mocked ones to
+ // facilitate testing. If Close() doesn't wait for watcher() goroutine
+ // finishes, race detector sometimes will warns lookup (READ the lookup
+ // function pointers) inside watcher() goroutine has data race with
+ // replaceNetFunc (WRITE the lookup function pointers).
wg sync.WaitGroup
disableServiceConfig bool
}
-// ResolveNow invoke an immediate resolution of the target that this dnsResolver watches.
+// ResolveNow invoke an immediate resolution of the target that this
+// dnsResolver watches.
func (d *dnsResolver) ResolveNow(resolver.ResolveNowOptions) {
select {
case d.rn <- struct{}{}:
@@ -220,8 +225,8 @@ func (d *dnsResolver) watcher() {
var timer *time.Timer
if err == nil {
- // Success resolving, wait for the next ResolveNow. However, also wait 30 seconds at the very least
- // to prevent constantly re-resolving.
+ // 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)
select {
@@ -231,7 +236,8 @@ func (d *dnsResolver) watcher() {
case <-d.rn:
}
} else {
- // Poll on an error found in DNS Resolver or an error received from ClientConn.
+ // Poll on an error found in DNS Resolver or an error received from
+ // ClientConn.
timer = newTimer(backoff.DefaultExponential.Backoff(backoffIndex))
backoffIndex++
}
@@ -278,7 +284,8 @@ func (d *dnsResolver) lookupSRV() ([]resolver.Address, error) {
}
func handleDNSError(err error, lookupType string) error {
- if dnsErr, ok := err.(*net.DNSError); ok && !dnsErr.IsTimeout && !dnsErr.IsTemporary {
+ dnsErr, ok := err.(*net.DNSError)
+ if ok && !dnsErr.IsTimeout && !dnsErr.IsTemporary {
// Timeouts and temporary errors should be communicated to gRPC to
// attempt another DNS query (with backoff). Other errors should be
// suppressed (they may represent the absence of a TXT record).
@@ -307,10 +314,12 @@ func (d *dnsResolver) lookupTXT() *serviceconfig.ParseResult {
res += s
}
- // TXT record must have "grpc_config=" attribute in order to be used as service config.
+ // TXT record must have "grpc_config=" attribute in order to be used as
+ // service config.
if !strings.HasPrefix(res, txtAttribute) {
logger.Warningf("dns: TXT record %v missing %v attribute", res, txtAttribute)
- // This is not an error; it is the equivalent of not having a service config.
+ // This is not an error; it is the equivalent of not having a service
+ // config.
return nil
}
sc := canaryingSC(strings.TrimPrefix(res, txtAttribute))
@@ -352,9 +361,10 @@ func (d *dnsResolver) lookup() (*resolver.State, error) {
return &state, nil
}
-// formatIP returns ok = false if addr is not a valid textual representation of an IP address.
-// If addr is an IPv4 address, return the addr and ok = true.
-// If addr is an IPv6 address, return the addr enclosed in square brackets and ok = true.
+// formatIP returns ok = false if addr is not a valid textual representation of
+// an IP address. If addr is an IPv4 address, return the addr and ok = true.
+// If addr is an IPv6 address, return the addr enclosed in square brackets and
+// ok = true.
func formatIP(addr string) (addrIP string, ok bool) {
ip := net.ParseIP(addr)
if ip == nil {
@@ -366,10 +376,10 @@ func formatIP(addr string) (addrIP string, ok bool) {
return "[" + addr + "]", true
}
-// parseTarget takes the user input target string and default port, returns formatted host and port info.
-// If target doesn't specify a port, set the port to be the defaultPort.
-// If target is in IPv6 format and host-name is enclosed in square brackets, brackets
-// are stripped when setting the host.
+// parseTarget takes the user input target string and default port, returns
+// formatted host and port info. If target doesn't specify a port, set the port
+// to be the defaultPort. If target is in IPv6 format and host-name is enclosed
+// in square brackets, brackets are stripped when setting the host.
// examples:
// target: "www.google.com" defaultPort: "443" returns host: "www.google.com", port: "443"
// target: "ipv4-host:80" defaultPort: "443" returns host: "ipv4-host", port: "80"
@@ -385,12 +395,14 @@ func parseTarget(target, defaultPort string) (host, port string, err error) {
}
if host, port, err = net.SplitHostPort(target); err == nil {
if port == "" {
- // If the port field is empty (target ends with colon), e.g. "[::1]:", this is an error.
+ // If the port field is empty (target ends with colon), e.g. "[::1]:",
+ // this is an error.
return "", "", errEndsWithColon
}
// target has port, i.e ipv4-host:port, [ipv6-host]:port, host-name:port
if host == "" {
- // Keep consistent with net.Dial(): If the host is empty, as in ":80", the local system is assumed.
+ // Keep consistent with net.Dial(): If the host is empty, as in ":80",
+ // the local system is assumed.
host = "localhost"
}
return host, port, nil
generated by cgit v1.2.3 (git 2.46.0) at 2025-07-13 16:06:48 +0000