diff options
Diffstat (limited to 'vendor/google.golang.org/grpc/grpclb_util.go')
| -rw-r--r-- | vendor/google.golang.org/grpc/grpclb_util.go | 214 |
1 files changed, 0 insertions, 214 deletions
diff --git a/vendor/google.golang.org/grpc/grpclb_util.go b/vendor/google.golang.org/grpc/grpclb_util.go deleted file mode 100644 index 063ba9d85..000000000 --- a/vendor/google.golang.org/grpc/grpclb_util.go +++ /dev/null @@ -1,214 +0,0 @@ -/* - * - * Copyright 2016 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 grpc - -import ( - "fmt" - "sync" - "time" - - "google.golang.org/grpc/balancer" - "google.golang.org/grpc/connectivity" - "google.golang.org/grpc/resolver" -) - -// The parent ClientConn should re-resolve when grpclb loses connection to the -// remote balancer. When the ClientConn inside grpclb gets a TransientFailure, -// it calls lbManualResolver.ResolveNow(), which calls parent ClientConn's -// ResolveNow, and eventually results in re-resolve happening in parent -// ClientConn's resolver (DNS for example). -// -// parent -// ClientConn -// +-----------------------------------------------------------------+ -// | parent +---------------------------------+ | -// | DNS ClientConn | grpclb | | -// | resolver balancerWrapper | | | -// | + + | grpclb grpclb | | -// | | | | ManualResolver ClientConn | | -// | | | | + + | | -// | | | | | | Transient | | -// | | | | | | Failure | | -// | | | | | <--------- | | | -// | | | <--------------- | ResolveNow | | | -// | | <--------- | ResolveNow | | | | | -// | | ResolveNow | | | | | | -// | | | | | | | | -// | + + | + + | | -// | +---------------------------------+ | -// +-----------------------------------------------------------------+ - -// lbManualResolver is used by the ClientConn inside grpclb. It's a manual -// resolver with a special ResolveNow() function. -// -// When ResolveNow() is called, it calls ResolveNow() on the parent ClientConn, -// so when grpclb client lose contact with remote balancers, the parent -// ClientConn's resolver will re-resolve. -type lbManualResolver struct { - scheme string - ccr resolver.ClientConn - - ccb balancer.ClientConn -} - -func (r *lbManualResolver) Build(_ resolver.Target, cc resolver.ClientConn, _ resolver.BuildOption) (resolver.Resolver, error) { - r.ccr = cc - return r, nil -} - -func (r *lbManualResolver) Scheme() string { - return r.scheme -} - -// ResolveNow calls resolveNow on the parent ClientConn. -func (r *lbManualResolver) ResolveNow(o resolver.ResolveNowOption) { - r.ccb.ResolveNow(o) -} - -// Close is a noop for Resolver. -func (*lbManualResolver) Close() {} - -// NewAddress calls cc.NewAddress. -func (r *lbManualResolver) NewAddress(addrs []resolver.Address) { - r.ccr.NewAddress(addrs) -} - -// NewServiceConfig calls cc.NewServiceConfig. -func (r *lbManualResolver) NewServiceConfig(sc string) { - r.ccr.NewServiceConfig(sc) -} - -const subConnCacheTime = time.Second * 10 - -// lbCacheClientConn is a wrapper balancer.ClientConn with a SubConn cache. -// SubConns will be kept in cache for subConnCacheTime before being removed. -// -// Its new and remove methods are updated to do cache first. -type lbCacheClientConn struct { - cc balancer.ClientConn - timeout time.Duration - - mu sync.Mutex - // subConnCache only keeps subConns that are being deleted. - subConnCache map[resolver.Address]*subConnCacheEntry - subConnToAddr map[balancer.SubConn]resolver.Address -} - -type subConnCacheEntry struct { - sc balancer.SubConn - - cancel func() - abortDeleting bool -} - -func newLBCacheClientConn(cc balancer.ClientConn) *lbCacheClientConn { - return &lbCacheClientConn{ - cc: cc, - timeout: subConnCacheTime, - subConnCache: make(map[resolver.Address]*subConnCacheEntry), - subConnToAddr: make(map[balancer.SubConn]resolver.Address), - } -} - -func (ccc *lbCacheClientConn) NewSubConn(addrs []resolver.Address, opts balancer.NewSubConnOptions) (balancer.SubConn, error) { - if len(addrs) != 1 { - return nil, fmt.Errorf("grpclb calling NewSubConn with addrs of length %v", len(addrs)) - } - addrWithoutMD := addrs[0] - addrWithoutMD.Metadata = nil - - ccc.mu.Lock() - defer ccc.mu.Unlock() - if entry, ok := ccc.subConnCache[addrWithoutMD]; ok { - // If entry is in subConnCache, the SubConn was being deleted. - // cancel function will never be nil. - entry.cancel() - delete(ccc.subConnCache, addrWithoutMD) - return entry.sc, nil - } - - scNew, err := ccc.cc.NewSubConn(addrs, opts) - if err != nil { - return nil, err - } - - ccc.subConnToAddr[scNew] = addrWithoutMD - return scNew, nil -} - -func (ccc *lbCacheClientConn) RemoveSubConn(sc balancer.SubConn) { - ccc.mu.Lock() - defer ccc.mu.Unlock() - addr, ok := ccc.subConnToAddr[sc] - if !ok { - return - } - - if entry, ok := ccc.subConnCache[addr]; ok { - if entry.sc != sc { - // This could happen if NewSubConn was called multiple times for the - // same address, and those SubConns are all removed. We remove sc - // immediately here. - delete(ccc.subConnToAddr, sc) - ccc.cc.RemoveSubConn(sc) - } - return - } - - entry := &subConnCacheEntry{ - sc: sc, - } - ccc.subConnCache[addr] = entry - - timer := time.AfterFunc(ccc.timeout, func() { - ccc.mu.Lock() - if entry.abortDeleting { - return - } - ccc.cc.RemoveSubConn(sc) - delete(ccc.subConnToAddr, sc) - delete(ccc.subConnCache, addr) - ccc.mu.Unlock() - }) - entry.cancel = func() { - if !timer.Stop() { - // If stop was not successful, the timer has fired (this can only - // happen in a race). But the deleting function is blocked on ccc.mu - // because the mutex was held by the caller of this function. - // - // Set abortDeleting to true to abort the deleting function. When - // the lock is released, the deleting function will acquire the - // lock, check the value of abortDeleting and return. - entry.abortDeleting = true - } - } -} - -func (ccc *lbCacheClientConn) UpdateBalancerState(s connectivity.State, p balancer.Picker) { - ccc.cc.UpdateBalancerState(s, p) -} - -func (ccc *lbCacheClientConn) close() { - ccc.mu.Lock() - // Only cancel all existing timers. There's no need to remove SubConns. - for _, entry := range ccc.subConnCache { - entry.cancel() - } - ccc.mu.Unlock() -} |