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-rw-r--r--vendor/google.golang.org/grpc/balancer/balancer.go274
-rw-r--r--vendor/google.golang.org/grpc/balancer/base/balancer.go208
-rw-r--r--vendor/google.golang.org/grpc/balancer/base/base.go52
-rw-r--r--vendor/google.golang.org/grpc/balancer/roundrobin/roundrobin.go79
4 files changed, 0 insertions, 613 deletions
diff --git a/vendor/google.golang.org/grpc/balancer/balancer.go b/vendor/google.golang.org/grpc/balancer/balancer.go
deleted file mode 100644
index 069feb1..0000000
--- a/vendor/google.golang.org/grpc/balancer/balancer.go
+++ /dev/null
@@ -1,274 +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 balancer defines APIs for load balancing in gRPC.
-// All APIs in this package are experimental.
-package balancer
-
-import (
- "errors"
- "net"
- "strings"
-
- "golang.org/x/net/context"
- "google.golang.org/grpc/connectivity"
- "google.golang.org/grpc/credentials"
- "google.golang.org/grpc/resolver"
-)
-
-var (
- // m is a map from name to balancer builder.
- m = make(map[string]Builder)
-)
-
-// Register registers the balancer builder to the balancer map. b.Name
-// (lowercased) will be used as the name 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 Balancers are
-// registered with the same name, the one registered last will take effect.
-func Register(b Builder) {
- m[strings.ToLower(b.Name())] = b
-}
-
-// Get returns the resolver builder registered with the given name.
-// Note that the compare is done in a case-insenstive fashion.
-// If no builder is register with the name, nil will be returned.
-func Get(name string) Builder {
- if b, ok := m[strings.ToLower(name)]; ok {
- return b
- }
- return nil
-}
-
-// SubConn represents a gRPC sub connection.
-// Each sub connection contains a list of addresses. gRPC will
-// try to connect to them (in sequence), and stop trying the
-// remainder once one connection is successful.
-//
-// The reconnect backoff will be applied on the list, not a single address.
-// For example, try_on_all_addresses -> backoff -> try_on_all_addresses.
-//
-// All SubConns start in IDLE, and will not try to connect. To trigger
-// the connecting, Balancers must call Connect.
-// When the connection encounters an error, it will reconnect immediately.
-// When the connection becomes IDLE, it will not reconnect unless Connect is
-// called.
-//
-// 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 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.
- UpdateAddresses([]resolver.Address)
- // Connect starts the connecting for this SubConn.
- Connect()
-}
-
-// NewSubConnOptions contains options to create new SubConn.
-type NewSubConnOptions struct{}
-
-// 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.
- NewSubConn([]resolver.Address, NewSubConnOptions) (SubConn, error)
- // RemoveSubConn removes the SubConn from ClientConn.
- // The SubConn will be shutdown.
- RemoveSubConn(SubConn)
-
- // UpdateBalancerState is called by balancer to nofity gRPC that some internal
- // state in balancer has changed.
- //
- // gRPC will update the connectivity state of the ClientConn, and will call pick
- // on the new picker to pick new SubConn.
- UpdateBalancerState(s connectivity.State, p Picker)
-
- // ResolveNow is called by balancer to notify gRPC to do a name resolving.
- ResolveNow(resolver.ResolveNowOption)
-
- // Target returns the dial target for this ClientConn.
- Target() string
-}
-
-// BuildOptions contains additional information for Build.
-type BuildOptions struct {
- // DialCreds is the transport credential the Balancer implementation can
- // use to dial to a remote load balancer server. The Balancer implementations
- // can ignore this if it does not need to talk to another party securely.
- DialCreds credentials.TransportCredentials
- // Dialer is the custom dialer the Balancer implementation can use to dial
- // to a remote load balancer server. The Balancer implementations
- // can ignore this if it doesn't need to talk to remote balancer.
- Dialer func(context.Context, string) (net.Conn, error)
- // ChannelzParentID is the entity parent's channelz unique identification number.
- ChannelzParentID int64
-}
-
-// 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
-}
-
-// PickOptions contains addition information for the Pick operation.
-type PickOptions struct {
- // FullMethodName is the method name that NewClientStream() is called
- // with. The canonical format is /service/Method.
- FullMethodName string
-}
-
-// DoneInfo contains additional information for done.
-type DoneInfo struct {
- // Err is the rpc error the RPC finished with. It could be nil.
- Err error
- // 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
-}
-
-var (
- // ErrNoSubConnAvailable indicates no SubConn is available for pick().
- // gRPC will block the RPC until a new picker is available via UpdateBalancerState().
- ErrNoSubConnAvailable = errors.New("no SubConn is available")
- // ErrTransientFailure indicates all SubConns are in TransientFailure.
- // WaitForReady RPCs will block, non-WaitForReady RPCs will fail.
- ErrTransientFailure = errors.New("all SubConns are in TransientFailure")
-)
-
-// 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.UpdateBalancerState().
-type Picker interface {
- // Pick returns the SubConn to be used to send the RPC.
- // The returned SubConn must be one returned by NewSubConn().
- //
- // This functions is expected to return:
- // - a SubConn that is known to be READY;
- // - ErrNoSubConnAvailable if no SubConn is available, but progress is being
- // made (for example, some SubConn is in CONNECTING mode);
- // - other errors if no active connecting is happening (for example, all SubConn
- // are in TRANSIENT_FAILURE mode).
- //
- // If a SubConn is returned:
- // - If it is READY, gRPC will send the RPC on it;
- // - If it is not ready, or becomes not ready after it's returned, gRPC will block
- // until UpdateBalancerState() is called and will call pick on the new picker.
- //
- // If the returned error is not nil:
- // - If the error is ErrNoSubConnAvailable, gRPC will block until UpdateBalancerState()
- // - If the error is ErrTransientFailure:
- // - If the RPC is wait-for-ready, gRPC will block until UpdateBalancerState()
- // is called to pick again;
- // - Otherwise, RPC will fail with unavailable error.
- // - Else (error is other non-nil error):
- // - The RPC will fail with unavailable error.
- //
- // The returned done() function will be called once the rpc has finished, with the
- // final status of that RPC.
- // done may be nil if balancer doesn't care about the RPC status.
- Pick(ctx context.Context, opts PickOptions) (conn SubConn, done func(DoneInfo), err 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.
-//
-// HandleSubConnectionStateChange, HandleResolvedAddrs 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 {
- // HandleSubConnStateChange is called by gRPC when the connectivity state
- // of sc has changed.
- // Balancer is expected to aggregate all the state of SubConn and report
- // that back to gRPC.
- // Balancer should also generate and update Pickers when its internal state has
- // been changed by the new state.
- HandleSubConnStateChange(sc SubConn, state connectivity.State)
- // HandleResolvedAddrs is called by gRPC to send updated resolved addresses to
- // balancers.
- // Balancer can create new SubConn or remove SubConn with the addresses.
- // An empty address slice and a non-nil error will be passed if the resolver returns
- // non-nil error to gRPC.
- HandleResolvedAddrs([]resolver.Address, error)
- // Close closes the balancer. The balancer is not required to call
- // ClientConn.RemoveSubConn for its existing SubConns.
- Close()
-}
-
-// 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 transientFailure.
-}
-
-// 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 the aggregated state is TransientFailure.
-//
-// Idle and Shutdown are 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
- }
- }
-
- // Evaluate.
- if cse.numReady > 0 {
- return connectivity.Ready
- }
- if cse.numConnecting > 0 {
- return connectivity.Connecting
- }
- return connectivity.TransientFailure
-}
diff --git a/vendor/google.golang.org/grpc/balancer/base/balancer.go b/vendor/google.golang.org/grpc/balancer/base/balancer.go
deleted file mode 100644
index 23d1351..0000000
--- a/vendor/google.golang.org/grpc/balancer/base/balancer.go
+++ /dev/null
@@ -1,208 +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 base
-
-import (
- "golang.org/x/net/context"
- "google.golang.org/grpc/balancer"
- "google.golang.org/grpc/connectivity"
- "google.golang.org/grpc/grpclog"
- "google.golang.org/grpc/resolver"
-)
-
-type baseBuilder struct {
- name string
- pickerBuilder PickerBuilder
-}
-
-func (bb *baseBuilder) Build(cc balancer.ClientConn, opt balancer.BuildOptions) balancer.Balancer {
- return &baseBalancer{
- cc: cc,
- pickerBuilder: bb.pickerBuilder,
-
- subConns: make(map[resolver.Address]balancer.SubConn),
- scStates: make(map[balancer.SubConn]connectivity.State),
- csEvltr: &connectivityStateEvaluator{},
- // Initialize picker to a picker that always return
- // ErrNoSubConnAvailable, because when state of a SubConn changes, we
- // may call UpdateBalancerState with this picker.
- picker: NewErrPicker(balancer.ErrNoSubConnAvailable),
- }
-}
-
-func (bb *baseBuilder) Name() string {
- return bb.name
-}
-
-type baseBalancer struct {
- cc balancer.ClientConn
- pickerBuilder PickerBuilder
-
- csEvltr *connectivityStateEvaluator
- state connectivity.State
-
- subConns map[resolver.Address]balancer.SubConn
- scStates map[balancer.SubConn]connectivity.State
- picker balancer.Picker
-}
-
-func (b *baseBalancer) HandleResolvedAddrs(addrs []resolver.Address, err error) {
- if err != nil {
- grpclog.Infof("base.baseBalancer: HandleResolvedAddrs called with error %v", err)
- return
- }
- grpclog.Infoln("base.baseBalancer: got new resolved addresses: ", addrs)
- // addrsSet is the set converted from addrs, it's used for quick lookup of an address.
- addrsSet := make(map[resolver.Address]struct{})
- for _, a := range addrs {
- addrsSet[a] = struct{}{}
- if _, ok := b.subConns[a]; !ok {
- // a is a new address (not existing in b.subConns).
- sc, err := b.cc.NewSubConn([]resolver.Address{a}, balancer.NewSubConnOptions{})
- if err != nil {
- grpclog.Warningf("base.baseBalancer: failed to create new SubConn: %v", err)
- continue
- }
- b.subConns[a] = sc
- b.scStates[sc] = connectivity.Idle
- sc.Connect()
- }
- }
- for a, sc := range b.subConns {
- // a was removed by resolver.
- if _, ok := addrsSet[a]; !ok {
- b.cc.RemoveSubConn(sc)
- delete(b.subConns, a)
- // Keep the state of this sc in b.scStates until sc's state becomes Shutdown.
- // The entry will be deleted in HandleSubConnStateChange.
- }
- }
-}
-
-// regeneratePicker takes a snapshot of the balancer, and generates a picker
-// from it. The picker is
-// - errPicker with ErrTransientFailure 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(balancer.ErrTransientFailure)
- return
- }
- readySCs := make(map[resolver.Address]balancer.SubConn)
-
- // Filter out all ready SCs from full subConn map.
- for addr, sc := range b.subConns {
- if st, ok := b.scStates[sc]; ok && st == connectivity.Ready {
- readySCs[addr] = sc
- }
- }
- b.picker = b.pickerBuilder.Build(readySCs)
-}
-
-func (b *baseBalancer) HandleSubConnStateChange(sc balancer.SubConn, s connectivity.State) {
- grpclog.Infof("base.baseBalancer: handle SubConn state change: %p, %v", sc, s)
- oldS, ok := b.scStates[sc]
- if !ok {
- grpclog.Infof("base.baseBalancer: got state changes for an unknown SubConn: %p, %v", sc, s)
- return
- }
- b.scStates[sc] = s
- switch s {
- case connectivity.Idle:
- sc.Connect()
- case connectivity.Shutdown:
- // When an address was removed by resolver, b called RemoveSubConn but
- // kept the sc's state in scStates. Remove state for this sc here.
- delete(b.scStates, sc)
- }
-
- oldAggrState := b.state
- b.state = b.csEvltr.recordTransition(oldS, s)
-
- // Regenerate picker when one of the following happens:
- // - this sc became ready from not-ready
- // - this sc became not-ready from ready
- // - the aggregated state of balancer became TransientFailure from non-TransientFailure
- // - the aggregated state of balancer became non-TransientFailure from TransientFailure
- if (s == connectivity.Ready) != (oldS == connectivity.Ready) ||
- (b.state == connectivity.TransientFailure) != (oldAggrState == connectivity.TransientFailure) {
- b.regeneratePicker()
- }
-
- b.cc.UpdateBalancerState(b.state, b.picker)
-}
-
-// Close is a nop because base balancer doesn't have internal state to clean up,
-// and it doesn't need to call RemoveSubConn for the SubConns.
-func (b *baseBalancer) Close() {
-}
-
-// NewErrPicker returns a picker that always returns err on Pick().
-func NewErrPicker(err error) balancer.Picker {
- return &errPicker{err: err}
-}
-
-type errPicker struct {
- err error // Pick() always returns this err.
-}
-
-func (p *errPicker) Pick(ctx context.Context, opts balancer.PickOptions) (balancer.SubConn, func(balancer.DoneInfo), error) {
- return nil, nil, p.err
-}
-
-// connectivityStateEvaluator gets updated by addrConns when their
-// states transition, based on which it evaluates the state of
-// ClientConn.
-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 transientFailure.
-}
-
-// recordTransition records state change happening in every subConn and based on
-// that it evaluates what aggregated state should be.
-// It can only transition between Ready, Connecting and TransientFailure. Other states,
-// Idle and Shutdown are transitioned into by ClientConn; in the beginning of the connection
-// before any subConn is created ClientConn is in idle state. In the end when ClientConn
-// closes it is in Shutdown state.
-//
-// recordTransition should only be called synchronously from the same goroutine.
-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
- }
- }
-
- // Evaluate.
- if cse.numReady > 0 {
- return connectivity.Ready
- }
- if cse.numConnecting > 0 {
- return connectivity.Connecting
- }
- return connectivity.TransientFailure
-}
diff --git a/vendor/google.golang.org/grpc/balancer/base/base.go b/vendor/google.golang.org/grpc/balancer/base/base.go
deleted file mode 100644
index 012ace2..0000000
--- a/vendor/google.golang.org/grpc/balancer/base/base.go
+++ /dev/null
@@ -1,52 +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 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 takes a slice of ready SubConns, and returns a picker that will be
- // used by gRPC to pick a SubConn.
- Build(readySCs map[resolver.Address]balancer.SubConn) balancer.Picker
-}
-
-// NewBalancerBuilder returns a balancer builder. The balancers
-// built by this builder will use the picker builder to build pickers.
-func NewBalancerBuilder(name string, pb PickerBuilder) balancer.Builder {
- return &baseBuilder{
- name: name,
- pickerBuilder: pb,
- }
-}
diff --git a/vendor/google.golang.org/grpc/balancer/roundrobin/roundrobin.go b/vendor/google.golang.org/grpc/balancer/roundrobin/roundrobin.go
deleted file mode 100644
index 2eda0a1..0000000
--- a/vendor/google.golang.org/grpc/balancer/roundrobin/roundrobin.go
+++ /dev/null
@@ -1,79 +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 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 (
- "sync"
-
- "golang.org/x/net/context"
- "google.golang.org/grpc/balancer"
- "google.golang.org/grpc/balancer/base"
- "google.golang.org/grpc/grpclog"
- "google.golang.org/grpc/resolver"
-)
-
-// Name is the name of round_robin balancer.
-const Name = "round_robin"
-
-// newBuilder creates a new roundrobin balancer builder.
-func newBuilder() balancer.Builder {
- return base.NewBalancerBuilder(Name, &rrPickerBuilder{})
-}
-
-func init() {
- balancer.Register(newBuilder())
-}
-
-type rrPickerBuilder struct{}
-
-func (*rrPickerBuilder) Build(readySCs map[resolver.Address]balancer.SubConn) balancer.Picker {
- grpclog.Infof("roundrobinPicker: newPicker called with readySCs: %v", readySCs)
- var scs []balancer.SubConn
- for _, sc := range readySCs {
- scs = append(scs, sc)
- }
- return &rrPicker{
- subConns: 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
-
- mu sync.Mutex
- next int
-}
-
-func (p *rrPicker) Pick(ctx context.Context, opts balancer.PickOptions) (balancer.SubConn, func(balancer.DoneInfo), error) {
- if len(p.subConns) <= 0 {
- return nil, nil, balancer.ErrNoSubConnAvailable
- }
-
- p.mu.Lock()
- sc := p.subConns[p.next]
- p.next = (p.next + 1) % len(p.subConns)
- p.mu.Unlock()
- return sc, nil, nil
-}