Fix transitions for image_download and activation
Change-Id: I713ada52eef9d275c7d7596026e178c7382e8335
diff --git a/vendor/google.golang.org/grpc/resolver/dns/dns_resolver.go b/vendor/google.golang.org/grpc/resolver/dns/dns_resolver.go
index 297492e..14aa6f2 100644
--- a/vendor/google.golang.org/grpc/resolver/dns/dns_resolver.go
+++ b/vendor/google.golang.org/grpc/resolver/dns/dns_resolver.go
@@ -18,440 +18,19 @@
// Package dns implements a dns resolver to be installed as the default resolver
// in grpc.
+//
+// Deprecated: this package is imported by grpc and should not need to be
+// imported directly by users.
package dns
import (
- "context"
- "encoding/json"
- "errors"
- "fmt"
- "net"
- "os"
- "strconv"
- "strings"
- "sync"
- "time"
-
- "google.golang.org/grpc/grpclog"
- "google.golang.org/grpc/internal/backoff"
- "google.golang.org/grpc/internal/grpcrand"
+ "google.golang.org/grpc/internal/resolver/dns"
"google.golang.org/grpc/resolver"
)
-func init() {
- resolver.Register(NewBuilder())
-}
-
-const (
- defaultPort = "443"
- defaultFreq = time.Minute * 30
- defaultDNSSvrPort = "53"
- golang = "GO"
- // 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.
- 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 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 dialer net.Dialer
- return dialer.DialContext(ctx, network, authority)
- }
-}
-
-var customAuthorityResolver = func(authority string) (netResolver, error) {
- host, port, err := parseTarget(authority, defaultDNSSvrPort)
- if err != nil {
- return nil, err
- }
-
- authorityWithPort := net.JoinHostPort(host, port)
-
- return &net.Resolver{
- PreferGo: true,
- Dial: customAuthorityDialler(authorityWithPort),
- }, nil
-}
-
// NewBuilder creates a dnsBuilder which is used to factory DNS resolvers.
+//
+// Deprecated: import grpc and use resolver.Get("dns") instead.
func NewBuilder() resolver.Builder {
- return &dnsBuilder{minFreq: defaultFreq}
-}
-
-type dnsBuilder struct {
- // minimum frequency of polling the DNS server.
- minFreq time.Duration
-}
-
-// 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.BuildOption) (resolver.Resolver, error) {
- host, port, err := parseTarget(target.Endpoint, defaultPort)
- if err != nil {
- return nil, err
- }
-
- // IP address.
- if net.ParseIP(host) != nil {
- host, _ = formatIP(host)
- addr := []resolver.Address{{Addr: host + ":" + port}}
- i := &ipResolver{
- cc: cc,
- ip: addr,
- rn: make(chan struct{}, 1),
- q: make(chan struct{}),
- }
- cc.NewAddress(addr)
- go i.watcher()
- return i, nil
- }
-
- // DNS address (non-IP).
- ctx, cancel := context.WithCancel(context.Background())
- d := &dnsResolver{
- freq: b.minFreq,
- backoff: backoff.Exponential{MaxDelay: b.minFreq},
- host: host,
- port: port,
- ctx: ctx,
- cancel: cancel,
- cc: cc,
- t: time.NewTimer(0),
- rn: make(chan struct{}, 1),
- disableServiceConfig: opts.DisableServiceConfig,
- }
-
- if target.Authority == "" {
- d.resolver = defaultResolver
- } else {
- d.resolver, err = customAuthorityResolver(target.Authority)
- if err != nil {
- return nil, err
- }
- }
-
- d.wg.Add(1)
- go d.watcher()
- return d, nil
-}
-
-// Scheme returns the naming scheme of this resolver builder, which is "dns".
-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)
-}
-
-// ipResolver watches for the name resolution update for an IP address.
-type ipResolver struct {
- cc resolver.ClientConn
- ip []resolver.Address
- // rn channel is used by ResolveNow() to force an immediate resolution of the target.
- rn chan struct{}
- q chan struct{}
-}
-
-// ResolveNow resend the address it stores, no resolution is needed.
-func (i *ipResolver) ResolveNow(opt resolver.ResolveNowOption) {
- select {
- case i.rn <- struct{}{}:
- default:
- }
-}
-
-// Close closes the ipResolver.
-func (i *ipResolver) Close() {
- close(i.q)
-}
-
-func (i *ipResolver) watcher() {
- for {
- select {
- case <-i.rn:
- i.cc.NewAddress(i.ip)
- case <-i.q:
- return
- }
- }
-}
-
-// dnsResolver watches for the name resolution update for a non-IP target.
-type dnsResolver struct {
- freq time.Duration
- backoff backoff.Exponential
- retryCount int
- host string
- port string
- resolver netResolver
- ctx context.Context
- cancel context.CancelFunc
- cc resolver.ClientConn
- // rn channel is used by ResolveNow() to force an immediate resolution of the target.
- rn chan struct{}
- t *time.Timer
- // 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.
-func (d *dnsResolver) ResolveNow(opt resolver.ResolveNowOption) {
- select {
- case d.rn <- struct{}{}:
- default:
- }
-}
-
-// Close closes the dnsResolver.
-func (d *dnsResolver) Close() {
- d.cancel()
- d.wg.Wait()
- d.t.Stop()
-}
-
-func (d *dnsResolver) watcher() {
- defer d.wg.Done()
- for {
- select {
- case <-d.ctx.Done():
- return
- case <-d.t.C:
- case <-d.rn:
- if !d.t.Stop() {
- // Before resetting a timer, it should be stopped to prevent racing with
- // reads on it's channel.
- <-d.t.C
- }
- }
-
- result, sc := d.lookup()
- // Next lookup should happen within an interval defined by d.freq. It may be
- // more often due to exponential retry on empty address list.
- if len(result) == 0 {
- d.retryCount++
- d.t.Reset(d.backoff.Backoff(d.retryCount))
- } else {
- d.retryCount = 0
- d.t.Reset(d.freq)
- }
- d.cc.NewServiceConfig(sc)
- d.cc.NewAddress(result)
-
- // Sleep to prevent excessive re-resolutions. Incoming resolution requests
- // will be queued in d.rn.
- t := time.NewTimer(minDNSResRate)
- select {
- case <-t.C:
- case <-d.ctx.Done():
- t.Stop()
- return
- }
- }
-}
-
-func (d *dnsResolver) lookupSRV() []resolver.Address {
- var newAddrs []resolver.Address
- _, srvs, err := d.resolver.LookupSRV(d.ctx, "grpclb", "tcp", d.host)
- if err != nil {
- grpclog.Infof("grpc: failed dns SRV record lookup due to %v.\n", err)
- return nil
- }
- for _, s := range srvs {
- lbAddrs, err := d.resolver.LookupHost(d.ctx, s.Target)
- if err != nil {
- grpclog.Infof("grpc: failed load balancer address dns lookup due to %v.\n", err)
- continue
- }
- for _, a := range lbAddrs {
- a, ok := formatIP(a)
- if !ok {
- grpclog.Errorf("grpc: failed IP parsing due to %v.\n", err)
- continue
- }
- addr := a + ":" + strconv.Itoa(int(s.Port))
- newAddrs = append(newAddrs, resolver.Address{Addr: addr, Type: resolver.GRPCLB, ServerName: s.Target})
- }
- }
- return newAddrs
-}
-
-func (d *dnsResolver) lookupTXT() string {
- ss, err := d.resolver.LookupTXT(d.ctx, txtPrefix+d.host)
- if err != nil {
- grpclog.Infof("grpc: failed dns TXT record lookup due to %v.\n", err)
- return ""
- }
- var res string
- for _, s := range ss {
- res += s
- }
-
- // TXT record must have "grpc_config=" attribute in order to be used as service config.
- if !strings.HasPrefix(res, txtAttribute) {
- grpclog.Warningf("grpc: TXT record %v missing %v attribute", res, txtAttribute)
- return ""
- }
- return strings.TrimPrefix(res, txtAttribute)
-}
-
-func (d *dnsResolver) lookupHost() []resolver.Address {
- var newAddrs []resolver.Address
- addrs, err := d.resolver.LookupHost(d.ctx, d.host)
- if err != nil {
- grpclog.Warningf("grpc: failed dns A record lookup due to %v.\n", err)
- return nil
- }
- for _, a := range addrs {
- a, ok := formatIP(a)
- if !ok {
- grpclog.Errorf("grpc: failed IP parsing due to %v.\n", err)
- continue
- }
- addr := a + ":" + d.port
- newAddrs = append(newAddrs, resolver.Address{Addr: addr})
- }
- return newAddrs
-}
-
-func (d *dnsResolver) lookup() ([]resolver.Address, string) {
- newAddrs := d.lookupSRV()
- // Support fallback to non-balancer address.
- newAddrs = append(newAddrs, d.lookupHost()...)
- if d.disableServiceConfig {
- return newAddrs, ""
- }
- sc := d.lookupTXT()
- return newAddrs, canaryingSC(sc)
-}
-
-// 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 {
- return "", false
- }
- if ip.To4() != nil {
- return addr, true
- }
- 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.
-// 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"
-// target: "[ipv6-host]" defaultPort: "443" returns host: "ipv6-host", port: "443"
-// target: ":80" defaultPort: "443" returns host: "localhost", port: "80"
-func parseTarget(target, defaultPort string) (host, port string, err error) {
- if target == "" {
- return "", "", errMissingAddr
- }
- if ip := net.ParseIP(target); ip != nil {
- // target is an IPv4 or IPv6(without brackets) address
- return target, defaultPort, nil
- }
- 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.
- 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.
- host = "localhost"
- }
- return host, port, nil
- }
- if host, port, err = net.SplitHostPort(target + ":" + defaultPort); err == nil {
- // target doesn't have port
- return host, port, nil
- }
- return "", "", fmt.Errorf("invalid target address %v, error info: %v", target, err)
-}
-
-type rawChoice struct {
- ClientLanguage *[]string `json:"clientLanguage,omitempty"`
- Percentage *int `json:"percentage,omitempty"`
- ClientHostName *[]string `json:"clientHostName,omitempty"`
- ServiceConfig *json.RawMessage `json:"serviceConfig,omitempty"`
-}
-
-func containsString(a *[]string, b string) bool {
- if a == nil {
- return true
- }
- for _, c := range *a {
- if c == b {
- return true
- }
- }
- return false
-}
-
-func chosenByPercentage(a *int) bool {
- if a == nil {
- return true
- }
- return grpcrand.Intn(100)+1 <= *a
-}
-
-func canaryingSC(js string) string {
- if js == "" {
- return ""
- }
- var rcs []rawChoice
- err := json.Unmarshal([]byte(js), &rcs)
- if err != nil {
- grpclog.Warningf("grpc: failed to parse service config json string due to %v.\n", err)
- return ""
- }
- cliHostname, err := os.Hostname()
- if err != nil {
- grpclog.Warningf("grpc: failed to get client hostname due to %v.\n", err)
- return ""
- }
- var sc string
- for _, c := range rcs {
- if !containsString(c.ClientLanguage, golang) ||
- !chosenByPercentage(c.Percentage) ||
- !containsString(c.ClientHostName, cliHostname) ||
- c.ServiceConfig == nil {
- continue
- }
- sc = string(*c.ServiceConfig)
- break
- }
- return sc
+ return dns.NewBuilder()
}