diff options
Diffstat (limited to 'vendor/google.golang.org/grpc/resolver/resolver.go')
| -rw-r--r-- | vendor/google.golang.org/grpc/resolver/resolver.go | 350 |
1 files changed, 0 insertions, 350 deletions
diff --git a/vendor/google.golang.org/grpc/resolver/resolver.go b/vendor/google.golang.org/grpc/resolver/resolver.go deleted file mode 100644 index 8eb1cf3bc..000000000 --- a/vendor/google.golang.org/grpc/resolver/resolver.go +++ /dev/null @@ -1,350 +0,0 @@ -/* - * - * 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" - "errors" - "fmt" - "net" - "net/url" - "strings" - - "google.golang.org/grpc/attributes" - "google.golang.org/grpc/credentials" - "google.golang.org/grpc/internal" - "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. The registry is case -// sensitive, and schemes should not contain any uppercase characters. -// -// 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 -// scheme is initially set to "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 - internal.UserSetDefaultScheme = true -} - -// GetDefaultScheme gets the default scheme that will be used by grpc.Dial. If -// SetDefaultScheme is never called, the default scheme used by grpc.NewClient is "dns" instead. -func GetDefaultScheme() string { - return defaultScheme -} - -// 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. - // - // 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 SubConn. - Attributes *attributes.Attributes - - // BalancerAttributes contains arbitrary data about this address intended - // for consumption by the LB policy. These attributes do not affect SubConn - // creation, connection establishment, handshaking, etc. - // - // Deprecated: when an Address is inside an Endpoint, this field should not - // be used, and it will eventually be removed entirely. - BalancerAttributes *attributes.Attributes - - // Metadata is the information associated with Addr, which may be used - // to make load balancing decision. - // - // Deprecated: use Attributes instead. - Metadata any -} - -// Equal returns whether a and o are identical. Metadata is compared directly, -// not with any recursive introspection. -// -// This method compares all fields of the address. When used to tell apart -// addresses during subchannel creation or connection establishment, it might be -// more appropriate for the caller to implement custom equality logic. -func (a Address) Equal(o Address) bool { - return a.Addr == o.Addr && a.ServerName == o.ServerName && - a.Attributes.Equal(o.Attributes) && - a.BalancerAttributes.Equal(o.BalancerAttributes) && - a.Metadata == o.Metadata -} - -// String returns JSON formatted string representation of the address. -func (a Address) String() string { - var sb strings.Builder - sb.WriteString(fmt.Sprintf("{Addr: %q, ", a.Addr)) - sb.WriteString(fmt.Sprintf("ServerName: %q, ", a.ServerName)) - if a.Attributes != nil { - sb.WriteString(fmt.Sprintf("Attributes: %v, ", a.Attributes.String())) - } - if a.BalancerAttributes != nil { - sb.WriteString(fmt.Sprintf("BalancerAttributes: %v", a.BalancerAttributes.String())) - } - sb.WriteString("}") - return sb.String() -} - -// 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) - // Authority is the effective authority of the clientconn for which the - // resolver is built. - Authority string -} - -// An Endpoint is one network endpoint, or server, which may have multiple -// addresses with which it can be accessed. -type Endpoint struct { - // Addresses contains a list of addresses used to access this endpoint. - Addresses []Address - - // Attributes contains arbitrary data about this endpoint intended for - // consumption by the LB policy. - Attributes *attributes.Attributes -} - -// State contains the current Resolver state relevant to the ClientConn. -type State struct { - // Addresses is the latest set of resolved addresses for the target. - // - // If a resolver sets Addresses but does not set Endpoints, one Endpoint - // will be created for each Address before the State is passed to the LB - // policy. The BalancerAttributes of each entry in Addresses will be set - // in Endpoints.Attributes, and be cleared in the Endpoint's Address's - // BalancerAttributes. - // - // Soon, Addresses will be deprecated and replaced fully by Endpoints. - Addresses []Address - - // Endpoints is the latest set of resolved endpoints for the target. - // - // If a resolver produces a State containing Endpoints but not Addresses, - // it must take care to ensure the LB policies it selects will support - // Endpoints. - Endpoints []Endpoint - - // 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. - // - // If an error is returned, the resolver should try to resolve the - // target again. The resolver should use a backoff timer to prevent - // overloading the server with requests. If a resolver is certain that - // reresolving will not change the result, e.g. because it is - // a watch-based resolver, returned errors can be ignored. - // - // If the resolved State is the same as the last reported one, calling - // UpdateState can be omitted. - UpdateState(State) error - // ReportError notifies the ClientConn that the Resolver encountered an - // error. The ClientConn then forwards this error to the load balancing - // policy. - 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) - // 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. If the -// target does not contain a scheme or if the parsed scheme is not registered -// (i.e. no corresponding resolver available to resolve the endpoint), we will -// apply the default scheme, and will attempt to reparse it. -type Target struct { - // URL contains the parsed dial target with an optional default scheme added - // to it if the original dial target contained no scheme or contained an - // unregistered scheme. Any query params specified in the original dial - // target can be accessed from here. - URL url.URL -} - -// Endpoint retrieves endpoint without leading "/" from either `URL.Path` -// or `URL.Opaque`. The latter is used when the former is empty. -func (t Target) Endpoint() string { - endpoint := t.URL.Path - if endpoint == "" { - endpoint = t.URL.Opaque - } - // For targets of the form "[scheme]://[authority]/endpoint, the endpoint - // value returned from url.Parse() contains a leading "/". Although this is - // in accordance with RFC 3986, we do not want to break existing resolver - // implementations which expect the endpoint without the leading "/". So, we - // end up stripping the leading "/" here. But this will result in an - // incorrect parsing for something like "unix:///path/to/socket". Since we - // own the "unix" resolver, we can workaround in the unix resolver by using - // the `URL` field. - return strings.TrimPrefix(endpoint, "/") -} - -// String returns the canonical string representation of Target. -func (t Target) String() string { - return t.URL.Scheme + "://" + t.URL.Host + "/" + t.Endpoint() -} - -// 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. The returned - // string should not contain uppercase characters, as they will not match - // the parsed target's scheme as defined in RFC 3986. - 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() -} - -// AuthorityOverrider is implemented by Builders that wish to override the -// default authority for the ClientConn. -// By default, the authority used is target.Endpoint(). -type AuthorityOverrider interface { - // OverrideAuthority returns the authority to use for a ClientConn with the - // given target. The implementation must generate it without blocking, - // typically in line, and must keep it unchanged. - OverrideAuthority(Target) string -} - -// ValidateEndpoints validates endpoints from a petiole policy's perspective. -// Petiole policies should call this before calling into their children. See -// [gRPC A61](https://github.com/grpc/proposal/blob/master/A61-IPv4-IPv6-dualstack-backends.md) -// for details. -func ValidateEndpoints(endpoints []Endpoint) error { - if len(endpoints) == 0 { - return errors.New("endpoints list is empty") - } - - for _, endpoint := range endpoints { - for range endpoint.Addresses { - return nil - } - } - return errors.New("endpoints list contains no addresses") -} |