[VOL-4289] Proto changes for gRPC migration
Change-Id: I317a0a865ccf78d0c37aa229c50d293a3f66c8bb
diff --git a/vendor/google.golang.org/grpc/resolver/resolver.go b/vendor/google.golang.org/grpc/resolver/resolver.go
new file mode 100644
index 0000000..6a9d234
--- /dev/null
+++ b/vendor/google.golang.org/grpc/resolver/resolver.go
@@ -0,0 +1,260 @@
+/*
+ *
+ * Copyright 2017 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 resolver defines APIs for name resolution in gRPC.
+// All APIs in this package are experimental.
+package resolver
+
+import (
+ "context"
+ "net"
+
+ "google.golang.org/grpc/attributes"
+ "google.golang.org/grpc/credentials"
+ "google.golang.org/grpc/serviceconfig"
+)
+
+var (
+ // m is a map from scheme to resolver builder.
+ m = make(map[string]Builder)
+ // defaultScheme is the default scheme to use.
+ defaultScheme = "passthrough"
+)
+
+// TODO(bar) install dns resolver in init(){}.
+
+// Register registers the resolver builder to the resolver map. b.Scheme will be
+// used as the scheme registered with this builder.
+//
+// NOTE: this function must only be called during initialization time (i.e. in
+// an init() function), and is not thread-safe. If multiple Resolvers are
+// registered with the same name, the one registered last will take effect.
+func Register(b Builder) {
+ m[b.Scheme()] = b
+}
+
+// Get returns the resolver builder registered with the given scheme.
+//
+// If no builder is register with the scheme, nil will be returned.
+func Get(scheme string) Builder {
+ if b, ok := m[scheme]; ok {
+ return b
+ }
+ return nil
+}
+
+// SetDefaultScheme sets the default scheme that will be used. The default
+// default scheme is "passthrough".
+//
+// NOTE: this function must only be called during initialization time (i.e. in
+// an init() function), and is not thread-safe. The scheme set last overrides
+// previously set values.
+func SetDefaultScheme(scheme string) {
+ defaultScheme = scheme
+}
+
+// GetDefaultScheme gets the default scheme that will be used.
+func GetDefaultScheme() string {
+ return defaultScheme
+}
+
+// AddressType indicates the address type returned by name resolution.
+//
+// Deprecated: use Attributes in Address instead.
+type AddressType uint8
+
+const (
+ // Backend indicates the address is for a backend server.
+ //
+ // Deprecated: use Attributes in Address instead.
+ Backend AddressType = iota
+ // GRPCLB indicates the address is for a grpclb load balancer.
+ //
+ // Deprecated: to select the GRPCLB load balancing policy, use a service
+ // config with a corresponding loadBalancingConfig. To supply balancer
+ // addresses to the GRPCLB load balancing policy, set State.Attributes
+ // using balancer/grpclb/state.Set.
+ GRPCLB
+)
+
+// Address represents a server the client connects to.
+//
+// Experimental
+//
+// Notice: This type is EXPERIMENTAL and may be changed or removed in a
+// later release.
+type Address struct {
+ // Addr is the server address on which a connection will be established.
+ Addr string
+
+ // ServerName is the name of this address.
+ // If non-empty, the ServerName is used as the transport certification authority for
+ // the address, instead of the hostname from the Dial target string. In most cases,
+ // this should not be set.
+ //
+ // If Type is GRPCLB, ServerName should be the name of the remote load
+ // balancer, not the name of the backend.
+ //
+ // WARNING: ServerName must only be populated with trusted values. It
+ // is insecure to populate it with data from untrusted inputs since untrusted
+ // values could be used to bypass the authority checks performed by TLS.
+ ServerName string
+
+ // Attributes contains arbitrary data about this address intended for
+ // consumption by the load balancing policy.
+ Attributes *attributes.Attributes
+
+ // Type is the type of this address.
+ //
+ // Deprecated: use Attributes instead.
+ Type AddressType
+
+ // Metadata is the information associated with Addr, which may be used
+ // to make load balancing decision.
+ //
+ // Deprecated: use Attributes instead.
+ Metadata interface{}
+}
+
+// BuildOptions includes additional information for the builder to create
+// the resolver.
+type BuildOptions struct {
+ // DisableServiceConfig indicates whether a resolver implementation should
+ // fetch service config data.
+ DisableServiceConfig bool
+ // DialCreds is the transport credentials used by the ClientConn for
+ // communicating with the target gRPC service (set via
+ // WithTransportCredentials). In cases where a name resolution service
+ // requires the same credentials, the resolver may use this field. In most
+ // cases though, it is not appropriate, and this field may be ignored.
+ DialCreds credentials.TransportCredentials
+ // CredsBundle is the credentials bundle used by the ClientConn for
+ // communicating with the target gRPC service (set via
+ // WithCredentialsBundle). In cases where a name resolution service
+ // requires the same credentials, the resolver may use this field. In most
+ // cases though, it is not appropriate, and this field may be ignored.
+ CredsBundle credentials.Bundle
+ // Dialer is the custom dialer used by the ClientConn for dialling the
+ // target gRPC service (set via WithDialer). In cases where a name
+ // resolution service requires the same dialer, the resolver may use this
+ // field. In most cases though, it is not appropriate, and this field may
+ // be ignored.
+ Dialer func(context.Context, string) (net.Conn, error)
+}
+
+// State contains the current Resolver state relevant to the ClientConn.
+type State struct {
+ // Addresses is the latest set of resolved addresses for the target.
+ Addresses []Address
+
+ // ServiceConfig contains the result from parsing the latest service
+ // config. If it is nil, it indicates no service config is present or the
+ // resolver does not provide service configs.
+ ServiceConfig *serviceconfig.ParseResult
+
+ // Attributes contains arbitrary data about the resolver intended for
+ // consumption by the load balancing policy.
+ Attributes *attributes.Attributes
+}
+
+// ClientConn contains the callbacks for resolver to notify any updates
+// to the gRPC ClientConn.
+//
+// This interface is to be implemented by gRPC. Users should not need a
+// brand new implementation of this interface. For the situations like
+// testing, the new implementation should embed this interface. This allows
+// gRPC to add new methods to this interface.
+type ClientConn interface {
+ // UpdateState updates the state of the ClientConn appropriately.
+ UpdateState(State) error
+ // ReportError notifies the ClientConn that the Resolver encountered an
+ // error. The ClientConn will notify the load balancer and begin calling
+ // ResolveNow on the Resolver with exponential backoff.
+ ReportError(error)
+ // NewAddress is called by resolver to notify ClientConn a new list
+ // of resolved addresses.
+ // The address list should be the complete list of resolved addresses.
+ //
+ // Deprecated: Use UpdateState instead.
+ NewAddress(addresses []Address)
+ // NewServiceConfig is called by resolver to notify ClientConn a new
+ // service config. The service config should be provided as a json string.
+ //
+ // Deprecated: Use UpdateState instead.
+ NewServiceConfig(serviceConfig string)
+ // ParseServiceConfig parses the provided service config and returns an
+ // object that provides the parsed config.
+ ParseServiceConfig(serviceConfigJSON string) *serviceconfig.ParseResult
+}
+
+// Target represents a target for gRPC, as specified in:
+// https://github.com/grpc/grpc/blob/master/doc/naming.md.
+// It is parsed from the target string that gets passed into Dial or DialContext by the user. And
+// grpc passes it to the resolver and the balancer.
+//
+// If the target follows the naming spec, and the parsed scheme is registered with grpc, we will
+// parse the target string according to the spec. e.g. "dns://some_authority/foo.bar" will be parsed
+// into &Target{Scheme: "dns", Authority: "some_authority", Endpoint: "foo.bar"}
+//
+// If the target does not contain a scheme, we will apply the default scheme, and set the Target to
+// be the full target string. e.g. "foo.bar" will be parsed into
+// &Target{Scheme: resolver.GetDefaultScheme(), Endpoint: "foo.bar"}.
+//
+// If the parsed scheme is not registered (i.e. no corresponding resolver available to resolve the
+// endpoint), we set the Scheme to be the default scheme, and set the Endpoint to be the full target
+// string. e.g. target string "unknown_scheme://authority/endpoint" will be parsed into
+// &Target{Scheme: resolver.GetDefaultScheme(), Endpoint: "unknown_scheme://authority/endpoint"}.
+type Target struct {
+ Scheme string
+ Authority string
+ Endpoint string
+}
+
+// Builder creates a resolver that will be used to watch name resolution updates.
+type Builder interface {
+ // Build creates a new resolver for the given target.
+ //
+ // gRPC dial calls Build synchronously, and fails if the returned error is
+ // not nil.
+ Build(target Target, cc ClientConn, opts BuildOptions) (Resolver, error)
+ // Scheme returns the scheme supported by this resolver.
+ // Scheme is defined at https://github.com/grpc/grpc/blob/master/doc/naming.md.
+ Scheme() string
+}
+
+// ResolveNowOptions includes additional information for ResolveNow.
+type ResolveNowOptions struct{}
+
+// Resolver watches for the updates on the specified target.
+// Updates include address updates and service config updates.
+type Resolver interface {
+ // ResolveNow will be called by gRPC to try to resolve the target name
+ // again. It's just a hint, resolver can ignore this if it's not necessary.
+ //
+ // It could be called multiple times concurrently.
+ ResolveNow(ResolveNowOptions)
+ // Close closes the resolver.
+ Close()
+}
+
+// UnregisterForTesting removes the resolver builder with the given scheme from the
+// resolver map.
+// This function is for testing only.
+func UnregisterForTesting(scheme string) {
+ delete(m, scheme)
+}