chore: vendor

This commit is contained in:
2024-08-04 11:06:58 +02:00
parent 2a5985e44e
commit 04aec8232f
3557 changed files with 981078 additions and 1 deletions

443
vendor/google.golang.org/grpc/balancer/balancer.go generated vendored Normal file
View File

@ -0,0 +1,443 @@
/*
*
* 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 balancer defines APIs for load balancing in gRPC.
// All APIs in this package are experimental.
package balancer
import (
"context"
"encoding/json"
"errors"
"net"
"strings"
"google.golang.org/grpc/channelz"
"google.golang.org/grpc/connectivity"
"google.golang.org/grpc/credentials"
"google.golang.org/grpc/grpclog"
"google.golang.org/grpc/internal"
"google.golang.org/grpc/metadata"
"google.golang.org/grpc/resolver"
"google.golang.org/grpc/serviceconfig"
)
var (
// m is a map from name to balancer builder.
m = make(map[string]Builder)
logger = grpclog.Component("balancer")
)
// Register registers the balancer builder to the balancer map. b.Name
// (lowercased) will be used as the name registered with this builder. If the
// Builder implements ConfigParser, ParseConfig will be called when new service
// configs are received by the resolver, and the result will be provided to the
// Balancer in UpdateClientConnState.
//
// NOTE: this function must only be called during initialization time (i.e. in
// an init() function), and is not thread-safe. If multiple Balancers are
// registered with the same name, the one registered last will take effect.
func Register(b Builder) {
name := strings.ToLower(b.Name())
if name != b.Name() {
// TODO: Skip the use of strings.ToLower() to index the map after v1.59
// is released to switch to case sensitive balancer registry. Also,
// remove this warning and update the docstrings for Register and Get.
logger.Warningf("Balancer registered with name %q. grpc-go will be switching to case sensitive balancer registries soon", b.Name())
}
m[name] = b
}
// unregisterForTesting deletes the balancer with the given name from the
// balancer map.
//
// This function is not thread-safe.
func unregisterForTesting(name string) {
delete(m, name)
}
func init() {
internal.BalancerUnregister = unregisterForTesting
}
// Get returns the resolver builder registered with the given name.
// Note that the compare is done in a case-insensitive fashion.
// If no builder is register with the name, nil will be returned.
func Get(name string) Builder {
if strings.ToLower(name) != name {
// TODO: Skip the use of strings.ToLower() to index the map after v1.59
// is released to switch to case sensitive balancer registry. Also,
// remove this warning and update the docstrings for Register and Get.
logger.Warningf("Balancer retrieved for name %q. grpc-go will be switching to case sensitive balancer registries soon", name)
}
if b, ok := m[strings.ToLower(name)]; ok {
return b
}
return nil
}
// A SubConn represents a single connection to a gRPC backend service.
//
// Each SubConn contains a list of addresses.
//
// All SubConns start in IDLE, and will not try to connect. To trigger the
// connecting, Balancers must call Connect. If a connection re-enters IDLE,
// Balancers must call Connect again to trigger a new connection attempt.
//
// gRPC will try to connect to the addresses in sequence, and stop trying the
// remainder once the first connection is successful. If an attempt to connect
// to all addresses encounters an error, the SubConn will enter
// TRANSIENT_FAILURE for a backoff period, and then transition to IDLE.
//
// Once established, if a connection is lost, the SubConn will transition
// directly to IDLE.
//
// This interface is to be implemented by gRPC. Users should not need their own
// implementation of this interface. For situations like testing, any
// implementations should embed this interface. This allows gRPC to add new
// methods to this interface.
type SubConn interface {
// UpdateAddresses updates the addresses used in this SubConn.
// gRPC checks if currently-connected address is still in the new list.
// If it's in the list, the connection will be kept.
// If it's not in the list, the connection will gracefully closed, and
// a new connection will be created.
//
// This will trigger a state transition for the SubConn.
//
// Deprecated: this method will be removed. Create new SubConns for new
// addresses instead.
UpdateAddresses([]resolver.Address)
// Connect starts the connecting for this SubConn.
Connect()
// GetOrBuildProducer returns a reference to the existing Producer for this
// ProducerBuilder in this SubConn, or, if one does not currently exist,
// creates a new one and returns it. Returns a close function which must
// be called when the Producer is no longer needed.
GetOrBuildProducer(ProducerBuilder) (p Producer, close func())
// Shutdown shuts down the SubConn gracefully. Any started RPCs will be
// allowed to complete. No future calls should be made on the SubConn.
// One final state update will be delivered to the StateListener (or
// UpdateSubConnState; deprecated) with ConnectivityState of Shutdown to
// indicate the shutdown operation. This may be delivered before
// in-progress RPCs are complete and the actual connection is closed.
Shutdown()
}
// NewSubConnOptions contains options to create new SubConn.
type NewSubConnOptions struct {
// CredsBundle is the credentials bundle that will be used in the created
// SubConn. If it's nil, the original creds from grpc DialOptions will be
// used.
//
// Deprecated: Use the Attributes field in resolver.Address to pass
// arbitrary data to the credential handshaker.
CredsBundle credentials.Bundle
// HealthCheckEnabled indicates whether health check service should be
// enabled on this SubConn
HealthCheckEnabled bool
// StateListener is called when the state of the subconn changes. If nil,
// Balancer.UpdateSubConnState will be called instead. Will never be
// invoked until after Connect() is called on the SubConn created with
// these options.
StateListener func(SubConnState)
}
// State contains the balancer's state relevant to the gRPC ClientConn.
type State struct {
// State contains the connectivity state of the balancer, which is used to
// determine the state of the ClientConn.
ConnectivityState connectivity.State
// Picker is used to choose connections (SubConns) for RPCs.
Picker Picker
}
// ClientConn represents a 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 {
// NewSubConn is called by balancer to create a new SubConn.
// It doesn't block and wait for the connections to be established.
// Behaviors of the SubConn can be controlled by options.
//
// Deprecated: please be aware that in a future version, SubConns will only
// support one address per SubConn.
NewSubConn([]resolver.Address, NewSubConnOptions) (SubConn, error)
// RemoveSubConn removes the SubConn from ClientConn.
// The SubConn will be shutdown.
//
// Deprecated: use SubConn.Shutdown instead.
RemoveSubConn(SubConn)
// UpdateAddresses updates the addresses used in the passed in SubConn.
// gRPC checks if the currently connected address is still in the new list.
// If so, the connection will be kept. Else, the connection will be
// gracefully closed, and a new connection will be created.
//
// This may trigger a state transition for the SubConn.
//
// Deprecated: this method will be removed. Create new SubConns for new
// addresses instead.
UpdateAddresses(SubConn, []resolver.Address)
// UpdateState notifies gRPC that the balancer's internal state has
// changed.
//
// gRPC will update the connectivity state of the ClientConn, and will call
// Pick on the new Picker to pick new SubConns.
UpdateState(State)
// ResolveNow is called by balancer to notify gRPC to do a name resolving.
ResolveNow(resolver.ResolveNowOptions)
// Target returns the dial target for this ClientConn.
//
// Deprecated: Use the Target field in the BuildOptions instead.
Target() string
}
// BuildOptions contains additional information for Build.
type BuildOptions struct {
// DialCreds is the transport credentials to use when communicating with a
// remote load balancer server. Balancer implementations which do not
// communicate with a remote load balancer server can ignore this field.
DialCreds credentials.TransportCredentials
// CredsBundle is the credentials bundle to use when communicating with a
// remote load balancer server. Balancer implementations which do not
// communicate with a remote load balancer server can ignore this field.
CredsBundle credentials.Bundle
// Dialer is the custom dialer to use when communicating with a remote load
// balancer server. Balancer implementations which do not communicate with a
// remote load balancer server can ignore this field.
Dialer func(context.Context, string) (net.Conn, error)
// Authority is the server name to use as part of the authentication
// handshake when communicating with a remote load balancer server. Balancer
// implementations which do not communicate with a remote load balancer
// server can ignore this field.
Authority string
// ChannelzParent is the parent ClientConn's channelz channel.
ChannelzParent channelz.Identifier
// CustomUserAgent is the custom user agent set on the parent ClientConn.
// The balancer should set the same custom user agent if it creates a
// ClientConn.
CustomUserAgent string
// Target contains the parsed address info of the dial target. It is the
// same resolver.Target as passed to the resolver. See the documentation for
// the resolver.Target type for details about what it contains.
Target resolver.Target
}
// Builder creates a balancer.
type Builder interface {
// Build creates a new balancer with the ClientConn.
Build(cc ClientConn, opts BuildOptions) Balancer
// Name returns the name of balancers built by this builder.
// It will be used to pick balancers (for example in service config).
Name() string
}
// ConfigParser parses load balancer configs.
type ConfigParser interface {
// ParseConfig parses the JSON load balancer config provided into an
// internal form or returns an error if the config is invalid. For future
// compatibility reasons, unknown fields in the config should be ignored.
ParseConfig(LoadBalancingConfigJSON json.RawMessage) (serviceconfig.LoadBalancingConfig, error)
}
// PickInfo contains additional information for the Pick operation.
type PickInfo struct {
// FullMethodName is the method name that NewClientStream() is called
// with. The canonical format is /service/Method.
FullMethodName string
// Ctx is the RPC's context, and may contain relevant RPC-level information
// like the outgoing header metadata.
Ctx context.Context
}
// DoneInfo contains additional information for done.
type DoneInfo struct {
// Err is the rpc error the RPC finished with. It could be nil.
Err error
// Trailer contains the metadata from the RPC's trailer, if present.
Trailer metadata.MD
// BytesSent indicates if any bytes have been sent to the server.
BytesSent bool
// BytesReceived indicates if any byte has been received from the server.
BytesReceived bool
// ServerLoad is the load received from server. It's usually sent as part of
// trailing metadata.
//
// The only supported type now is *orca_v3.LoadReport.
ServerLoad any
}
var (
// ErrNoSubConnAvailable indicates no SubConn is available for pick().
// gRPC will block the RPC until a new picker is available via UpdateState().
ErrNoSubConnAvailable = errors.New("no SubConn is available")
// ErrTransientFailure indicates all SubConns are in TransientFailure.
// WaitForReady RPCs will block, non-WaitForReady RPCs will fail.
//
// Deprecated: return an appropriate error based on the last resolution or
// connection attempt instead. The behavior is the same for any non-gRPC
// status error.
ErrTransientFailure = errors.New("all SubConns are in TransientFailure")
)
// PickResult contains information related to a connection chosen for an RPC.
type PickResult struct {
// SubConn is the connection to use for this pick, if its state is Ready.
// If the state is not Ready, gRPC will block the RPC until a new Picker is
// provided by the balancer (using ClientConn.UpdateState). The SubConn
// must be one returned by ClientConn.NewSubConn.
SubConn SubConn
// Done is called when the RPC is completed. If the SubConn is not ready,
// this will be called with a nil parameter. If the SubConn is not a valid
// type, Done may not be called. May be nil if the balancer does not wish
// to be notified when the RPC completes.
Done func(DoneInfo)
// Metadata provides a way for LB policies to inject arbitrary per-call
// metadata. Any metadata returned here will be merged with existing
// metadata added by the client application.
//
// LB policies with child policies are responsible for propagating metadata
// injected by their children to the ClientConn, as part of Pick().
Metadata metadata.MD
}
// TransientFailureError returns e. It exists for backward compatibility and
// will be deleted soon.
//
// Deprecated: no longer necessary, picker errors are treated this way by
// default.
func TransientFailureError(e error) error { return e }
// Picker is used by gRPC to pick a SubConn to send an RPC.
// Balancer is expected to generate a new picker from its snapshot every time its
// internal state has changed.
//
// The pickers used by gRPC can be updated by ClientConn.UpdateState().
type Picker interface {
// Pick returns the connection to use for this RPC and related information.
//
// Pick should not block. If the balancer needs to do I/O or any blocking
// or time-consuming work to service this call, it should return
// ErrNoSubConnAvailable, and the Pick call will be repeated by gRPC when
// the Picker is updated (using ClientConn.UpdateState).
//
// If an error is returned:
//
// - If the error is ErrNoSubConnAvailable, gRPC will block until a new
// Picker is provided by the balancer (using ClientConn.UpdateState).
//
// - If the error is a status error (implemented by the grpc/status
// package), gRPC will terminate the RPC with the code and message
// provided.
//
// - For all other errors, wait for ready RPCs will wait, but non-wait for
// ready RPCs will be terminated with this error's Error() string and
// status code Unavailable.
Pick(info PickInfo) (PickResult, error)
}
// Balancer takes input from gRPC, manages SubConns, and collects and aggregates
// the connectivity states.
//
// It also generates and updates the Picker used by gRPC to pick SubConns for RPCs.
//
// UpdateClientConnState, ResolverError, UpdateSubConnState, and Close are
// guaranteed to be called synchronously from the same goroutine. There's no
// guarantee on picker.Pick, it may be called anytime.
type Balancer interface {
// UpdateClientConnState is called by gRPC when the state of the ClientConn
// changes. If the error returned is ErrBadResolverState, the ClientConn
// will begin calling ResolveNow on the active name resolver with
// exponential backoff until a subsequent call to UpdateClientConnState
// returns a nil error. Any other errors are currently ignored.
UpdateClientConnState(ClientConnState) error
// ResolverError is called by gRPC when the name resolver reports an error.
ResolverError(error)
// UpdateSubConnState is called by gRPC when the state of a SubConn
// changes.
//
// Deprecated: Use NewSubConnOptions.StateListener when creating the
// SubConn instead.
UpdateSubConnState(SubConn, SubConnState)
// Close closes the balancer. The balancer is not currently required to
// call SubConn.Shutdown for its existing SubConns; however, this will be
// required in a future release, so it is recommended.
Close()
}
// ExitIdler is an optional interface for balancers to implement. If
// implemented, ExitIdle will be called when ClientConn.Connect is called, if
// the ClientConn is idle. If unimplemented, ClientConn.Connect will cause
// all SubConns to connect.
//
// Notice: it will be required for all balancers to implement this in a future
// release.
type ExitIdler interface {
// ExitIdle instructs the LB policy to reconnect to backends / exit the
// IDLE state, if appropriate and possible. Note that SubConns that enter
// the IDLE state will not reconnect until SubConn.Connect is called.
ExitIdle()
}
// SubConnState describes the state of a SubConn.
type SubConnState struct {
// ConnectivityState is the connectivity state of the SubConn.
ConnectivityState connectivity.State
// ConnectionError is set if the ConnectivityState is TransientFailure,
// describing the reason the SubConn failed. Otherwise, it is nil.
ConnectionError error
}
// ClientConnState describes the state of a ClientConn relevant to the
// balancer.
type ClientConnState struct {
ResolverState resolver.State
// The parsed load balancing configuration returned by the builder's
// ParseConfig method, if implemented.
BalancerConfig serviceconfig.LoadBalancingConfig
}
// ErrBadResolverState may be returned by UpdateClientConnState to indicate a
// problem with the provided name resolver data.
var ErrBadResolverState = errors.New("bad resolver state")
// A ProducerBuilder is a simple constructor for a Producer. It is used by the
// SubConn to create producers when needed.
type ProducerBuilder interface {
// Build creates a Producer. The first parameter is always a
// grpc.ClientConnInterface (a type to allow creating RPCs/streams on the
// associated SubConn), but is declared as `any` to avoid a dependency
// cycle. Should also return a close function that will be called when all
// references to the Producer have been given up.
Build(grpcClientConnInterface any) (p Producer, close func())
}
// A Producer is a type shared among potentially many consumers. It is
// associated with a SubConn, and an implementation will typically contain
// other methods to provide additional functionality, e.g. configuration or
// subscription registration.
type Producer any

264
vendor/google.golang.org/grpc/balancer/base/balancer.go generated vendored Normal file
View File

@ -0,0 +1,264 @@
/*
*
* 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 base
import (
"errors"
"fmt"
"google.golang.org/grpc/balancer"
"google.golang.org/grpc/connectivity"
"google.golang.org/grpc/grpclog"
"google.golang.org/grpc/resolver"
)
var logger = grpclog.Component("balancer")
type baseBuilder struct {
name string
pickerBuilder PickerBuilder
config Config
}
func (bb *baseBuilder) Build(cc balancer.ClientConn, opt balancer.BuildOptions) balancer.Balancer {
bal := &baseBalancer{
cc: cc,
pickerBuilder: bb.pickerBuilder,
subConns: resolver.NewAddressMap(),
scStates: make(map[balancer.SubConn]connectivity.State),
csEvltr: &balancer.ConnectivityStateEvaluator{},
config: bb.config,
state: connectivity.Connecting,
}
// Initialize picker to a picker that always returns
// ErrNoSubConnAvailable, because when state of a SubConn changes, we
// may call UpdateState with this picker.
bal.picker = NewErrPicker(balancer.ErrNoSubConnAvailable)
return bal
}
func (bb *baseBuilder) Name() string {
return bb.name
}
type baseBalancer struct {
cc balancer.ClientConn
pickerBuilder PickerBuilder
csEvltr *balancer.ConnectivityStateEvaluator
state connectivity.State
subConns *resolver.AddressMap
scStates map[balancer.SubConn]connectivity.State
picker balancer.Picker
config Config
resolverErr error // the last error reported by the resolver; cleared on successful resolution
connErr error // the last connection error; cleared upon leaving TransientFailure
}
func (b *baseBalancer) ResolverError(err error) {
b.resolverErr = err
if b.subConns.Len() == 0 {
b.state = connectivity.TransientFailure
}
if b.state != connectivity.TransientFailure {
// The picker will not change since the balancer does not currently
// report an error.
return
}
b.regeneratePicker()
b.cc.UpdateState(balancer.State{
ConnectivityState: b.state,
Picker: b.picker,
})
}
func (b *baseBalancer) UpdateClientConnState(s balancer.ClientConnState) error {
// TODO: handle s.ResolverState.ServiceConfig?
if logger.V(2) {
logger.Info("base.baseBalancer: got new ClientConn state: ", s)
}
// Successful resolution; clear resolver error and ensure we return nil.
b.resolverErr = nil
// addrsSet is the set converted from addrs, it's used for quick lookup of an address.
addrsSet := resolver.NewAddressMap()
for _, a := range s.ResolverState.Addresses {
addrsSet.Set(a, nil)
if _, ok := b.subConns.Get(a); !ok {
// a is a new address (not existing in b.subConns).
var sc balancer.SubConn
opts := balancer.NewSubConnOptions{
HealthCheckEnabled: b.config.HealthCheck,
StateListener: func(scs balancer.SubConnState) { b.updateSubConnState(sc, scs) },
}
sc, err := b.cc.NewSubConn([]resolver.Address{a}, opts)
if err != nil {
logger.Warningf("base.baseBalancer: failed to create new SubConn: %v", err)
continue
}
b.subConns.Set(a, sc)
b.scStates[sc] = connectivity.Idle
b.csEvltr.RecordTransition(connectivity.Shutdown, connectivity.Idle)
sc.Connect()
}
}
for _, a := range b.subConns.Keys() {
sci, _ := b.subConns.Get(a)
sc := sci.(balancer.SubConn)
// a was removed by resolver.
if _, ok := addrsSet.Get(a); !ok {
sc.Shutdown()
b.subConns.Delete(a)
// Keep the state of this sc in b.scStates until sc's state becomes Shutdown.
// The entry will be deleted in updateSubConnState.
}
}
// If resolver state contains no addresses, return an error so ClientConn
// will trigger re-resolve. Also records this as an resolver error, so when
// the overall state turns transient failure, the error message will have
// the zero address information.
if len(s.ResolverState.Addresses) == 0 {
b.ResolverError(errors.New("produced zero addresses"))
return balancer.ErrBadResolverState
}
b.regeneratePicker()
b.cc.UpdateState(balancer.State{ConnectivityState: b.state, Picker: b.picker})
return nil
}
// mergeErrors builds an error from the last connection error and the last
// resolver error. Must only be called if b.state is TransientFailure.
func (b *baseBalancer) mergeErrors() error {
// connErr must always be non-nil unless there are no SubConns, in which
// case resolverErr must be non-nil.
if b.connErr == nil {
return fmt.Errorf("last resolver error: %v", b.resolverErr)
}
if b.resolverErr == nil {
return fmt.Errorf("last connection error: %v", b.connErr)
}
return fmt.Errorf("last connection error: %v; last resolver error: %v", b.connErr, b.resolverErr)
}
// regeneratePicker takes a snapshot of the balancer, and generates a picker
// from it. The picker is
// - errPicker if the balancer is in TransientFailure,
// - built by the pickerBuilder with all READY SubConns otherwise.
func (b *baseBalancer) regeneratePicker() {
if b.state == connectivity.TransientFailure {
b.picker = NewErrPicker(b.mergeErrors())
return
}
readySCs := make(map[balancer.SubConn]SubConnInfo)
// Filter out all ready SCs from full subConn map.
for _, addr := range b.subConns.Keys() {
sci, _ := b.subConns.Get(addr)
sc := sci.(balancer.SubConn)
if st, ok := b.scStates[sc]; ok && st == connectivity.Ready {
readySCs[sc] = SubConnInfo{Address: addr}
}
}
b.picker = b.pickerBuilder.Build(PickerBuildInfo{ReadySCs: readySCs})
}
// UpdateSubConnState is a nop because a StateListener is always set in NewSubConn.
func (b *baseBalancer) UpdateSubConnState(sc balancer.SubConn, state balancer.SubConnState) {
logger.Errorf("base.baseBalancer: UpdateSubConnState(%v, %+v) called unexpectedly", sc, state)
}
func (b *baseBalancer) updateSubConnState(sc balancer.SubConn, state balancer.SubConnState) {
s := state.ConnectivityState
if logger.V(2) {
logger.Infof("base.baseBalancer: handle SubConn state change: %p, %v", sc, s)
}
oldS, ok := b.scStates[sc]
if !ok {
if logger.V(2) {
logger.Infof("base.baseBalancer: got state changes for an unknown SubConn: %p, %v", sc, s)
}
return
}
if oldS == connectivity.TransientFailure &&
(s == connectivity.Connecting || s == connectivity.Idle) {
// Once a subconn enters TRANSIENT_FAILURE, ignore subsequent IDLE or
// CONNECTING transitions to prevent the aggregated state from being
// always CONNECTING when many backends exist but are all down.
if s == connectivity.Idle {
sc.Connect()
}
return
}
b.scStates[sc] = s
switch s {
case connectivity.Idle:
sc.Connect()
case connectivity.Shutdown:
// When an address was removed by resolver, b called Shutdown but kept
// the sc's state in scStates. Remove state for this sc here.
delete(b.scStates, sc)
case connectivity.TransientFailure:
// Save error to be reported via picker.
b.connErr = state.ConnectionError
}
b.state = b.csEvltr.RecordTransition(oldS, s)
// Regenerate picker when one of the following happens:
// - this sc entered or left ready
// - the aggregated state of balancer is TransientFailure
// (may need to update error message)
if (s == connectivity.Ready) != (oldS == connectivity.Ready) ||
b.state == connectivity.TransientFailure {
b.regeneratePicker()
}
b.cc.UpdateState(balancer.State{ConnectivityState: b.state, Picker: b.picker})
}
// Close is a nop because base balancer doesn't have internal state to clean up,
// and it doesn't need to call Shutdown for the SubConns.
func (b *baseBalancer) Close() {
}
// ExitIdle is a nop because the base balancer attempts to stay connected to
// all SubConns at all times.
func (b *baseBalancer) ExitIdle() {
}
// NewErrPicker returns a Picker that always returns err on Pick().
func NewErrPicker(err error) balancer.Picker {
return &errPicker{err: err}
}
// NewErrPickerV2 is temporarily defined for backward compatibility reasons.
//
// Deprecated: use NewErrPicker instead.
var NewErrPickerV2 = NewErrPicker
type errPicker struct {
err error // Pick() always returns this err.
}
func (p *errPicker) Pick(info balancer.PickInfo) (balancer.PickResult, error) {
return balancer.PickResult{}, p.err
}

71
vendor/google.golang.org/grpc/balancer/base/base.go generated vendored Normal file
View File

@ -0,0 +1,71 @@
/*
*
* 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 base defines a balancer base that can be used to build balancers with
// different picking algorithms.
//
// The base balancer creates a new SubConn for each resolved address. The
// provided picker will only be notified about READY SubConns.
//
// This package is the base of round_robin balancer, its purpose is to be used
// to build round_robin like balancers with complex picking algorithms.
// Balancers with more complicated logic should try to implement a balancer
// builder from scratch.
//
// All APIs in this package are experimental.
package base
import (
"google.golang.org/grpc/balancer"
"google.golang.org/grpc/resolver"
)
// PickerBuilder creates balancer.Picker.
type PickerBuilder interface {
// Build returns a picker that will be used by gRPC to pick a SubConn.
Build(info PickerBuildInfo) balancer.Picker
}
// PickerBuildInfo contains information needed by the picker builder to
// construct a picker.
type PickerBuildInfo struct {
// ReadySCs is a map from all ready SubConns to the Addresses used to
// create them.
ReadySCs map[balancer.SubConn]SubConnInfo
}
// SubConnInfo contains information about a SubConn created by the base
// balancer.
type SubConnInfo struct {
Address resolver.Address // the address used to create this SubConn
}
// Config contains the config info about the base balancer builder.
type Config struct {
// HealthCheck indicates whether health checking should be enabled for this specific balancer.
HealthCheck bool
}
// NewBalancerBuilder returns a base balancer builder configured by the provided config.
func NewBalancerBuilder(name string, pb PickerBuilder, config Config) balancer.Builder {
return &baseBuilder{
name: name,
pickerBuilder: pb,
config: config,
}
}

View File

@ -0,0 +1,74 @@
/*
*
* Copyright 2022 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 balancer
import "google.golang.org/grpc/connectivity"
// ConnectivityStateEvaluator takes the connectivity states of multiple SubConns
// and returns one aggregated connectivity state.
//
// It's not thread safe.
type ConnectivityStateEvaluator struct {
numReady uint64 // Number of addrConns in ready state.
numConnecting uint64 // Number of addrConns in connecting state.
numTransientFailure uint64 // Number of addrConns in transient failure state.
numIdle uint64 // Number of addrConns in idle state.
}
// RecordTransition records state change happening in subConn and based on that
// it evaluates what aggregated state should be.
//
// - If at least one SubConn in Ready, the aggregated state is Ready;
// - Else if at least one SubConn in Connecting, the aggregated state is Connecting;
// - Else if at least one SubConn is Idle, the aggregated state is Idle;
// - Else if at least one SubConn is TransientFailure (or there are no SubConns), the aggregated state is Transient Failure.
//
// Shutdown is not considered.
func (cse *ConnectivityStateEvaluator) RecordTransition(oldState, newState connectivity.State) connectivity.State {
// Update counters.
for idx, state := range []connectivity.State{oldState, newState} {
updateVal := 2*uint64(idx) - 1 // -1 for oldState and +1 for new.
switch state {
case connectivity.Ready:
cse.numReady += updateVal
case connectivity.Connecting:
cse.numConnecting += updateVal
case connectivity.TransientFailure:
cse.numTransientFailure += updateVal
case connectivity.Idle:
cse.numIdle += updateVal
}
}
return cse.CurrentState()
}
// CurrentState returns the current aggregate conn state by evaluating the counters
func (cse *ConnectivityStateEvaluator) CurrentState() connectivity.State {
// Evaluate.
if cse.numReady > 0 {
return connectivity.Ready
}
if cse.numConnecting > 0 {
return connectivity.Connecting
}
if cse.numIdle > 0 {
return connectivity.Idle
}
return connectivity.TransientFailure
}

View File

@ -0,0 +1,51 @@
/*
*
* Copyright 2020 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 state declares grpclb types to be set by resolvers wishing to pass
// information to grpclb via resolver.State Attributes.
package state
import (
"google.golang.org/grpc/resolver"
)
// keyType is the key to use for storing State in Attributes.
type keyType string
const key = keyType("grpc.grpclb.state")
// State contains gRPCLB-relevant data passed from the name resolver.
type State struct {
// BalancerAddresses contains the remote load balancer address(es). If
// set, overrides any resolver-provided addresses with Type of GRPCLB.
BalancerAddresses []resolver.Address
}
// Set returns a copy of the provided state with attributes containing s. s's
// data should not be mutated after calling Set.
func Set(state resolver.State, s *State) resolver.State {
state.Attributes = state.Attributes.WithValue(key, s)
return state
}
// Get returns the grpclb State in the resolver.State, or nil if not present.
// The returned data should not be mutated.
func Get(state resolver.State) *State {
s, _ := state.Attributes.Value(key).(*State)
return s
}

View File

@ -0,0 +1,283 @@
/*
*
* 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 pickfirst contains the pick_first load balancing policy.
package pickfirst
import (
"encoding/json"
"errors"
"fmt"
"math/rand"
"google.golang.org/grpc/balancer"
"google.golang.org/grpc/connectivity"
"google.golang.org/grpc/grpclog"
"google.golang.org/grpc/internal"
internalgrpclog "google.golang.org/grpc/internal/grpclog"
"google.golang.org/grpc/internal/pretty"
"google.golang.org/grpc/resolver"
"google.golang.org/grpc/serviceconfig"
)
func init() {
balancer.Register(pickfirstBuilder{})
internal.ShuffleAddressListForTesting = func(n int, swap func(i, j int)) { rand.Shuffle(n, swap) }
}
var logger = grpclog.Component("pick-first-lb")
const (
// Name is the name of the pick_first balancer.
Name = "pick_first"
logPrefix = "[pick-first-lb %p] "
)
type pickfirstBuilder struct{}
func (pickfirstBuilder) Build(cc balancer.ClientConn, opt balancer.BuildOptions) balancer.Balancer {
b := &pickfirstBalancer{cc: cc}
b.logger = internalgrpclog.NewPrefixLogger(logger, fmt.Sprintf(logPrefix, b))
return b
}
func (pickfirstBuilder) Name() string {
return Name
}
type pfConfig struct {
serviceconfig.LoadBalancingConfig `json:"-"`
// If set to true, instructs the LB policy to shuffle the order of the list
// of endpoints received from the name resolver before attempting to
// connect to them.
ShuffleAddressList bool `json:"shuffleAddressList"`
}
func (pickfirstBuilder) ParseConfig(js json.RawMessage) (serviceconfig.LoadBalancingConfig, error) {
var cfg pfConfig
if err := json.Unmarshal(js, &cfg); err != nil {
return nil, fmt.Errorf("pickfirst: unable to unmarshal LB policy config: %s, error: %v", string(js), err)
}
return cfg, nil
}
type pickfirstBalancer struct {
logger *internalgrpclog.PrefixLogger
state connectivity.State
cc balancer.ClientConn
subConn balancer.SubConn
}
func (b *pickfirstBalancer) ResolverError(err error) {
if b.logger.V(2) {
b.logger.Infof("Received error from the name resolver: %v", err)
}
if b.subConn == nil {
b.state = connectivity.TransientFailure
}
if b.state != connectivity.TransientFailure {
// The picker will not change since the balancer does not currently
// report an error.
return
}
b.cc.UpdateState(balancer.State{
ConnectivityState: connectivity.TransientFailure,
Picker: &picker{err: fmt.Errorf("name resolver error: %v", err)},
})
}
type Shuffler interface {
ShuffleAddressListForTesting(n int, swap func(i, j int))
}
func ShuffleAddressListForTesting(n int, swap func(i, j int)) { rand.Shuffle(n, swap) }
func (b *pickfirstBalancer) UpdateClientConnState(state balancer.ClientConnState) error {
if len(state.ResolverState.Addresses) == 0 && len(state.ResolverState.Endpoints) == 0 {
// The resolver reported an empty address list. Treat it like an error by
// calling b.ResolverError.
if b.subConn != nil {
// Shut down the old subConn. All addresses were removed, so it is
// no longer valid.
b.subConn.Shutdown()
b.subConn = nil
}
b.ResolverError(errors.New("produced zero addresses"))
return balancer.ErrBadResolverState
}
// We don't have to guard this block with the env var because ParseConfig
// already does so.
cfg, ok := state.BalancerConfig.(pfConfig)
if state.BalancerConfig != nil && !ok {
return fmt.Errorf("pickfirst: received illegal BalancerConfig (type %T): %v", state.BalancerConfig, state.BalancerConfig)
}
if b.logger.V(2) {
b.logger.Infof("Received new config %s, resolver state %s", pretty.ToJSON(cfg), pretty.ToJSON(state.ResolverState))
}
var addrs []resolver.Address
if endpoints := state.ResolverState.Endpoints; len(endpoints) != 0 {
// Perform the optional shuffling described in gRFC A62. The shuffling will
// change the order of endpoints but not touch the order of the addresses
// within each endpoint. - A61
if cfg.ShuffleAddressList {
endpoints = append([]resolver.Endpoint{}, endpoints...)
internal.ShuffleAddressListForTesting.(func(int, func(int, int)))(len(endpoints), func(i, j int) { endpoints[i], endpoints[j] = endpoints[j], endpoints[i] })
}
// "Flatten the list by concatenating the ordered list of addresses for each
// of the endpoints, in order." - A61
for _, endpoint := range endpoints {
// "In the flattened list, interleave addresses from the two address
// families, as per RFC-8304 section 4." - A61
// TODO: support the above language.
addrs = append(addrs, endpoint.Addresses...)
}
} else {
// Endpoints not set, process addresses until we migrate resolver
// emissions fully to Endpoints. The top channel does wrap emitted
// addresses with endpoints, however some balancers such as weighted
// target do not forwarrd the corresponding correct endpoints down/split
// endpoints properly. Once all balancers correctly forward endpoints
// down, can delete this else conditional.
addrs = state.ResolverState.Addresses
if cfg.ShuffleAddressList {
addrs = append([]resolver.Address{}, addrs...)
rand.Shuffle(len(addrs), func(i, j int) { addrs[i], addrs[j] = addrs[j], addrs[i] })
}
}
if b.subConn != nil {
b.cc.UpdateAddresses(b.subConn, addrs)
return nil
}
var subConn balancer.SubConn
subConn, err := b.cc.NewSubConn(addrs, balancer.NewSubConnOptions{
StateListener: func(state balancer.SubConnState) {
b.updateSubConnState(subConn, state)
},
})
if err != nil {
if b.logger.V(2) {
b.logger.Infof("Failed to create new SubConn: %v", err)
}
b.state = connectivity.TransientFailure
b.cc.UpdateState(balancer.State{
ConnectivityState: connectivity.TransientFailure,
Picker: &picker{err: fmt.Errorf("error creating connection: %v", err)},
})
return balancer.ErrBadResolverState
}
b.subConn = subConn
b.state = connectivity.Idle
b.cc.UpdateState(balancer.State{
ConnectivityState: connectivity.Connecting,
Picker: &picker{err: balancer.ErrNoSubConnAvailable},
})
b.subConn.Connect()
return nil
}
// UpdateSubConnState is unused as a StateListener is always registered when
// creating SubConns.
func (b *pickfirstBalancer) UpdateSubConnState(subConn balancer.SubConn, state balancer.SubConnState) {
b.logger.Errorf("UpdateSubConnState(%v, %+v) called unexpectedly", subConn, state)
}
func (b *pickfirstBalancer) updateSubConnState(subConn balancer.SubConn, state balancer.SubConnState) {
if b.logger.V(2) {
b.logger.Infof("Received SubConn state update: %p, %+v", subConn, state)
}
if b.subConn != subConn {
if b.logger.V(2) {
b.logger.Infof("Ignored state change because subConn is not recognized")
}
return
}
if state.ConnectivityState == connectivity.Shutdown {
b.subConn = nil
return
}
switch state.ConnectivityState {
case connectivity.Ready:
b.cc.UpdateState(balancer.State{
ConnectivityState: state.ConnectivityState,
Picker: &picker{result: balancer.PickResult{SubConn: subConn}},
})
case connectivity.Connecting:
if b.state == connectivity.TransientFailure {
// We stay in TransientFailure until we are Ready. See A62.
return
}
b.cc.UpdateState(balancer.State{
ConnectivityState: state.ConnectivityState,
Picker: &picker{err: balancer.ErrNoSubConnAvailable},
})
case connectivity.Idle:
if b.state == connectivity.TransientFailure {
// We stay in TransientFailure until we are Ready. Also kick the
// subConn out of Idle into Connecting. See A62.
b.subConn.Connect()
return
}
b.cc.UpdateState(balancer.State{
ConnectivityState: state.ConnectivityState,
Picker: &idlePicker{subConn: subConn},
})
case connectivity.TransientFailure:
b.cc.UpdateState(balancer.State{
ConnectivityState: state.ConnectivityState,
Picker: &picker{err: state.ConnectionError},
})
}
b.state = state.ConnectivityState
}
func (b *pickfirstBalancer) Close() {
}
func (b *pickfirstBalancer) ExitIdle() {
if b.subConn != nil && b.state == connectivity.Idle {
b.subConn.Connect()
}
}
type picker struct {
result balancer.PickResult
err error
}
func (p *picker) Pick(balancer.PickInfo) (balancer.PickResult, error) {
return p.result, p.err
}
// idlePicker is used when the SubConn is IDLE and kicks the SubConn into
// CONNECTING when Pick is called.
type idlePicker struct {
subConn balancer.SubConn
}
func (i *idlePicker) Pick(balancer.PickInfo) (balancer.PickResult, error) {
i.subConn.Connect()
return balancer.PickResult{}, balancer.ErrNoSubConnAvailable
}

View File

@ -0,0 +1,81 @@
/*
*
* 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 roundrobin defines a roundrobin balancer. Roundrobin balancer is
// installed as one of the default balancers in gRPC, users don't need to
// explicitly install this balancer.
package roundrobin
import (
"math/rand"
"sync/atomic"
"google.golang.org/grpc/balancer"
"google.golang.org/grpc/balancer/base"
"google.golang.org/grpc/grpclog"
)
// Name is the name of round_robin balancer.
const Name = "round_robin"
var logger = grpclog.Component("roundrobin")
// newBuilder creates a new roundrobin balancer builder.
func newBuilder() balancer.Builder {
return base.NewBalancerBuilder(Name, &rrPickerBuilder{}, base.Config{HealthCheck: true})
}
func init() {
balancer.Register(newBuilder())
}
type rrPickerBuilder struct{}
func (*rrPickerBuilder) Build(info base.PickerBuildInfo) balancer.Picker {
logger.Infof("roundrobinPicker: Build called with info: %v", info)
if len(info.ReadySCs) == 0 {
return base.NewErrPicker(balancer.ErrNoSubConnAvailable)
}
scs := make([]balancer.SubConn, 0, len(info.ReadySCs))
for sc := range info.ReadySCs {
scs = append(scs, sc)
}
return &rrPicker{
subConns: scs,
// Start at a random index, as the same RR balancer rebuilds a new
// picker when SubConn states change, and we don't want to apply excess
// load to the first server in the list.
next: uint32(rand.Intn(len(scs))),
}
}
type rrPicker struct {
// subConns is the snapshot of the roundrobin balancer when this picker was
// created. The slice is immutable. Each Get() will do a round robin
// selection from it and return the selected SubConn.
subConns []balancer.SubConn
next uint32
}
func (p *rrPicker) Pick(balancer.PickInfo) (balancer.PickResult, error) {
subConnsLen := uint32(len(p.subConns))
nextIndex := atomic.AddUint32(&p.next, 1)
sc := p.subConns[nextIndex%subConnsLen]
return balancer.PickResult{SubConn: sc}, nil
}