grpc-go/xds/internal/xdsclient/callback.go

317 lines
10 KiB
Go

/*
*
* 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 xdsclient
import "google.golang.org/grpc/internal/pretty"
type watcherInfoWithUpdate struct {
wi *watchInfo
update interface{}
err error
}
// scheduleCallback should only be called by methods of watchInfo, which checks
// for watcher states and maintain consistency.
func (c *clientImpl) scheduleCallback(wi *watchInfo, update interface{}, err error) {
c.updateCh.Put(&watcherInfoWithUpdate{
wi: wi,
update: update,
err: err,
})
}
func (c *clientImpl) callCallback(wiu *watcherInfoWithUpdate) {
c.mu.Lock()
// Use a closure to capture the callback and type assertion, to save one
// more switch case.
//
// The callback must be called without c.mu. Otherwise if the callback calls
// another watch() inline, it will cause a deadlock. This leaves a small
// window that a watcher's callback could be called after the watcher is
// canceled, and the user needs to take care of it.
var ccb func()
switch wiu.wi.rType {
case ListenerResource:
if s, ok := c.ldsWatchers[wiu.wi.target]; ok && s[wiu.wi] {
ccb = func() { wiu.wi.ldsCallback(wiu.update.(ListenerUpdate), wiu.err) }
}
case RouteConfigResource:
if s, ok := c.rdsWatchers[wiu.wi.target]; ok && s[wiu.wi] {
ccb = func() { wiu.wi.rdsCallback(wiu.update.(RouteConfigUpdate), wiu.err) }
}
case ClusterResource:
if s, ok := c.cdsWatchers[wiu.wi.target]; ok && s[wiu.wi] {
ccb = func() { wiu.wi.cdsCallback(wiu.update.(ClusterUpdate), wiu.err) }
}
case EndpointsResource:
if s, ok := c.edsWatchers[wiu.wi.target]; ok && s[wiu.wi] {
ccb = func() { wiu.wi.edsCallback(wiu.update.(EndpointsUpdate), wiu.err) }
}
}
c.mu.Unlock()
if ccb != nil {
ccb()
}
}
// NewListeners is called by the underlying xdsAPIClient when it receives an
// xDS response.
//
// A response can contain multiple resources. They will be parsed and put in a
// map from resource name to the resource content.
func (c *clientImpl) NewListeners(updates map[string]ListenerUpdateErrTuple, metadata UpdateMetadata) {
c.mu.Lock()
defer c.mu.Unlock()
c.ldsVersion = metadata.Version
if metadata.ErrState != nil {
c.ldsVersion = metadata.ErrState.Version
}
for name, uErr := range updates {
if s, ok := c.ldsWatchers[name]; ok {
if uErr.Err != nil {
// On error, keep previous version for each resource. But update
// status and error.
mdCopy := c.ldsMD[name]
mdCopy.ErrState = metadata.ErrState
mdCopy.Status = metadata.Status
c.ldsMD[name] = mdCopy
for wi := range s {
wi.newError(uErr.Err)
}
continue
}
// If the resource is valid, send the update.
for wi := range s {
wi.newUpdate(uErr.Update)
}
// Sync cache.
c.logger.Debugf("LDS resource with name %v, value %+v added to cache", name, pretty.ToJSON(uErr))
c.ldsCache[name] = uErr.Update
// Set status to ACK, and clear error state. The metadata might be a
// NACK metadata because some other resources in the same response
// are invalid.
mdCopy := metadata
mdCopy.Status = ServiceStatusACKed
mdCopy.ErrState = nil
if metadata.ErrState != nil {
mdCopy.Version = metadata.ErrState.Version
}
c.ldsMD[name] = mdCopy
}
}
// Resources not in the new update were removed by the server, so delete
// them.
for name := range c.ldsCache {
if _, ok := updates[name]; !ok {
// If resource exists in cache, but not in the new update, delete
// the resource from cache, and also send an resource not found
// error to indicate resource removed.
delete(c.ldsCache, name)
c.ldsMD[name] = UpdateMetadata{Status: ServiceStatusNotExist}
for wi := range c.ldsWatchers[name] {
wi.resourceNotFound()
}
}
}
// When LDS resource is removed, we don't delete corresponding RDS cached
// data. The RDS watch will be canceled, and cache entry is removed when the
// last watch is canceled.
}
// NewRouteConfigs is called by the underlying xdsAPIClient when it receives an
// xDS response.
//
// A response can contain multiple resources. They will be parsed and put in a
// map from resource name to the resource content.
func (c *clientImpl) NewRouteConfigs(updates map[string]RouteConfigUpdateErrTuple, metadata UpdateMetadata) {
c.mu.Lock()
defer c.mu.Unlock()
// If no error received, the status is ACK.
c.rdsVersion = metadata.Version
if metadata.ErrState != nil {
c.rdsVersion = metadata.ErrState.Version
}
for name, uErr := range updates {
if s, ok := c.rdsWatchers[name]; ok {
if uErr.Err != nil {
// On error, keep previous version for each resource. But update
// status and error.
mdCopy := c.rdsMD[name]
mdCopy.ErrState = metadata.ErrState
mdCopy.Status = metadata.Status
c.rdsMD[name] = mdCopy
for wi := range s {
wi.newError(uErr.Err)
}
continue
}
// If the resource is valid, send the update.
for wi := range s {
wi.newUpdate(uErr.Update)
}
// Sync cache.
c.logger.Debugf("RDS resource with name %v, value %+v added to cache", name, pretty.ToJSON(uErr))
c.rdsCache[name] = uErr.Update
// Set status to ACK, and clear error state. The metadata might be a
// NACK metadata because some other resources in the same response
// are invalid.
mdCopy := metadata
mdCopy.Status = ServiceStatusACKed
mdCopy.ErrState = nil
if metadata.ErrState != nil {
mdCopy.Version = metadata.ErrState.Version
}
c.rdsMD[name] = mdCopy
}
}
}
// NewClusters is called by the underlying xdsAPIClient when it receives an xDS
// response.
//
// A response can contain multiple resources. They will be parsed and put in a
// map from resource name to the resource content.
func (c *clientImpl) NewClusters(updates map[string]ClusterUpdateErrTuple, metadata UpdateMetadata) {
c.mu.Lock()
defer c.mu.Unlock()
c.cdsVersion = metadata.Version
if metadata.ErrState != nil {
c.cdsVersion = metadata.ErrState.Version
}
for name, uErr := range updates {
if s, ok := c.cdsWatchers[name]; ok {
if uErr.Err != nil {
// On error, keep previous version for each resource. But update
// status and error.
mdCopy := c.cdsMD[name]
mdCopy.ErrState = metadata.ErrState
mdCopy.Status = metadata.Status
c.cdsMD[name] = mdCopy
for wi := range s {
// Send the watcher the individual error, instead of the
// overall combined error from the metadata.ErrState.
wi.newError(uErr.Err)
}
continue
}
// If the resource is valid, send the update.
for wi := range s {
wi.newUpdate(uErr.Update)
}
// Sync cache.
c.logger.Debugf("CDS resource with name %v, value %+v added to cache", name, pretty.ToJSON(uErr))
c.cdsCache[name] = uErr.Update
// Set status to ACK, and clear error state. The metadata might be a
// NACK metadata because some other resources in the same response
// are invalid.
mdCopy := metadata
mdCopy.Status = ServiceStatusACKed
mdCopy.ErrState = nil
if metadata.ErrState != nil {
mdCopy.Version = metadata.ErrState.Version
}
c.cdsMD[name] = mdCopy
}
}
// Resources not in the new update were removed by the server, so delete
// them.
for name := range c.cdsCache {
if _, ok := updates[name]; !ok {
// If resource exists in cache, but not in the new update, delete it
// from cache, and also send an resource not found error to indicate
// resource removed.
delete(c.cdsCache, name)
c.ldsMD[name] = UpdateMetadata{Status: ServiceStatusNotExist}
for wi := range c.cdsWatchers[name] {
wi.resourceNotFound()
}
}
}
// When CDS resource is removed, we don't delete corresponding EDS cached
// data. The EDS watch will be canceled, and cache entry is removed when the
// last watch is canceled.
}
// NewEndpoints is called by the underlying xdsAPIClient when it receives an
// xDS response.
//
// A response can contain multiple resources. They will be parsed and put in a
// map from resource name to the resource content.
func (c *clientImpl) NewEndpoints(updates map[string]EndpointsUpdateErrTuple, metadata UpdateMetadata) {
c.mu.Lock()
defer c.mu.Unlock()
c.edsVersion = metadata.Version
if metadata.ErrState != nil {
c.edsVersion = metadata.ErrState.Version
}
for name, uErr := range updates {
if s, ok := c.edsWatchers[name]; ok {
if uErr.Err != nil {
// On error, keep previous version for each resource. But update
// status and error.
mdCopy := c.edsMD[name]
mdCopy.ErrState = metadata.ErrState
mdCopy.Status = metadata.Status
c.edsMD[name] = mdCopy
for wi := range s {
// Send the watcher the individual error, instead of the
// overall combined error from the metadata.ErrState.
wi.newError(uErr.Err)
}
continue
}
// If the resource is valid, send the update.
for wi := range s {
wi.newUpdate(uErr.Update)
}
// Sync cache.
c.logger.Debugf("EDS resource with name %v, value %+v added to cache", name, pretty.ToJSON(uErr))
c.edsCache[name] = uErr.Update
// Set status to ACK, and clear error state. The metadata might be a
// NACK metadata because some other resources in the same response
// are invalid.
mdCopy := metadata
mdCopy.Status = ServiceStatusACKed
mdCopy.ErrState = nil
if metadata.ErrState != nil {
mdCopy.Version = metadata.ErrState.Version
}
c.edsMD[name] = mdCopy
}
}
}
// NewConnectionError is called by the underlying xdsAPIClient when it receives
// a connection error. The error will be forwarded to all the resource watchers.
func (c *clientImpl) NewConnectionError(err error) {
c.mu.Lock()
defer c.mu.Unlock()
for _, s := range c.edsWatchers {
for wi := range s {
wi.newError(NewErrorf(ErrorTypeConnection, "xds: error received from xDS stream: %v", err))
}
}
}