blob: c86530ffec3b87d2cce79e448cf9fcf612c01072 [file] [log] [blame]
/*
* Copyright 2018-present Open Networking Foundation
* 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 afrouter
import (
"fmt"
"github.com/golang/protobuf/proto"
"github.com/opencord/voltha-go/common/log"
"google.golang.org/grpc"
"regexp"
"strconv"
)
// TODO: Used in multiple routers, should move to common file
const (
PKG_MTHD_PKG int = 1
PKG_MTHD_MTHD int = 2
)
type AffinityRouter struct {
name string
association associationType
grpcService string
methodMap map[string]byte
nbBindingMethodMap map[string]byte
cluster *cluster
affinity map[string]*backend
currentBackend **backend
}
func newAffinityRouter(rconf *RouterConfig, config *RouteConfig) (Router, error) {
var err error
var rtrn_err = false
var pkg_re = regexp.MustCompile(`^(\.[^.]+\.)(.+)$`)
// Validate the configuration
// A name must exist
if config.Name == "" {
log.Error("A router 'name' must be specified")
rtrn_err = true
}
if rconf.ProtoPackage == "" {
log.Error("A 'package' must be specified")
rtrn_err = true
}
if rconf.ProtoService == "" {
log.Error("A 'service' must be specified")
rtrn_err = true
}
//if config.RouteField == "" {
// log.Error("A 'routing_field' must be specified")
// rtrn_err = true
//}
// TODO The overrieds section is currently not being used
// so the router will route all methods based on the
// routing_field. This needs to be added so that methods
// can have different routing fields.
var bptr *backend
dr := AffinityRouter{
name: config.Name,
grpcService: rconf.ProtoService,
affinity: make(map[string]*backend),
methodMap: make(map[string]byte),
nbBindingMethodMap: make(map[string]byte),
currentBackend: &bptr,
}
// An association must exist
dr.association = config.Association
if dr.association == AssociationUndefined {
log.Error("An association must be specified")
rtrn_err = true
}
// Build the routing structure based on the loaded protobuf
// descriptor file and the config information.
type key struct {
method string
field string
}
var fieldNumberLookup = make(map[key]byte)
for _, f := range rconf.protoDescriptor.File {
// Build a temporary map of message types by name.
for _, m := range f.MessageType {
for _, fld := range m.Field {
log.Debugf("Processing message '%s', field '%s'", *m.Name, *fld.Name)
fieldNumberLookup[key{*m.Name, *fld.Name}] = byte(*fld.Number)
}
}
}
for _, f := range rconf.protoDescriptor.File {
if *f.Package == rconf.ProtoPackage {
for _, s := range f.Service {
if *s.Name == rconf.ProtoService {
log.Debugf("Loading package data '%s' for service '%s' for router '%s'", *f.Package, *s.Name, dr.name)
// Now create a map keyed by method name with the value being the
// field number of the route selector.
var ok bool
for _, m := range s.Method {
// Find the input type in the messages and extract the
// field number and save it for future reference.
log.Debugf("Processing method '%s'", *m.Name)
// Determine if this is a method we're supposed to be processing.
if needMethod(*m.Name, config) {
log.Debugf("Enabling method '%s'", *m.Name)
pkg_methd := pkg_re.FindStringSubmatch(*m.InputType)
if pkg_methd == nil {
log.Errorf("Regular expression didn't match input type '%s'", *m.InputType)
rtrn_err = true
}
// The input type has the package name prepended to it. Remove it.
//in := (*m.InputType)[len(rconf.ProtoPackage)+2:]
in := pkg_methd[PKG_MTHD_MTHD]
dr.methodMap[*m.Name], ok = fieldNumberLookup[key{in, config.RouteField}]
if !ok {
log.Errorf("Method '%s' has no field named '%s' in it's parameter message '%s'",
*m.Name, config.RouteField, in)
rtrn_err = true
}
}
// The sb method is always included in the methods so we can check it here too.
if needNbBindingMethod(*m.Name, config) {
log.Debugf("Enabling southbound method '%s'", *m.Name)
// The output type has the package name prepended to it. Remove it.
out := (*m.OutputType)[len(rconf.ProtoPackage)+2:]
dr.nbBindingMethodMap[*m.Name], ok = fieldNumberLookup[key{out, config.RouteField}]
if !ok {
log.Errorf("Method '%s' has no field named '%s' in it's parameter message '%s'",
*m.Name, config.RouteField, out)
rtrn_err = true
}
}
}
}
}
}
}
// Create the backend cluster or link to an existing one
var ok bool
if dr.cluster, ok = clusters[config.backendCluster.Name]; !ok {
if dr.cluster, err = newBackendCluster(config.backendCluster); err != nil {
log.Errorf("Could not create a backend for router %s", config.Name)
rtrn_err = true
}
}
if rtrn_err {
return dr, fmt.Errorf("Failed to create a new router '%s'", dr.name)
}
return dr, nil
}
func needNbBindingMethod(mthd string, conf *RouteConfig) bool {
for _, m := range conf.NbBindingMethods {
if mthd == m {
return true
}
}
return false
}
// TODO: Used in multiple routers, should move to common file
func needMethod(mthd string, conf *RouteConfig) bool {
for _, m := range conf.Methods {
if mthd == m {
return true
}
}
return false
}
func (ar AffinityRouter) Service() string {
return ar.grpcService
}
func (ar AffinityRouter) Name() string {
return ar.name
}
func (ar AffinityRouter) skipField(data *[]byte, idx *int) error {
switch (*data)[*idx] & 3 {
case 0: // Varint
// skip the field number/type
*idx++
// if the msb is set, then more bytes to follow
for (*data)[*idx] >= 128 {
*idx++
}
// the last byte doesn't have the msb set
*idx++
case 1: // 64 bit
*idx += 9
case 2: // Length delimited
*idx++
b := proto.NewBuffer((*data)[*idx:])
t, _ := b.DecodeVarint()
*idx += int(t) + 1
case 3: // Deprecated
case 4: // Deprecated
case 5: // 32 bit
*idx += 5
}
return nil
}
func (ar AffinityRouter) decodeProtoField(payload []byte, fieldId byte) (string, error) {
idx := 0
b := proto.NewBuffer([]byte{})
//b.DebugPrint("The Buffer", payload)
for { // Find the route selector field
if idx >= len(payload) {
err := fmt.Errorf("At end of message, attribute %d not found", fieldId)
return "", err
}
log.Debugf("Decoding afinity value attributeNumber: %d from %v at index %d", fieldId, payload, idx)
log.Debugf("Attempting match with payload: %d, methodTable: %d", payload[idx], fieldId)
if payload[idx]>>3 == fieldId {
log.Debugf("Method match with payload: %d, methodTable: %d", payload[idx], fieldId)
// TODO: Consider supporting other selector types.... Way, way in the future
// ok, the future is now, support strings as well... ugh.
var selector string
switch payload[idx] & 3 {
case 0: // Integer
b.SetBuf(payload[idx+1:])
v, e := b.DecodeVarint()
if e == nil {
log.Debugf("Decoded the ing field: %v", v)
selector = strconv.Itoa(int(v))
} else {
log.Errorf("Failed to decode varint %v", e)
return "", e
}
case 2: // Length delimited AKA string
b.SetBuf(payload[idx+1:])
v, e := b.DecodeStringBytes()
if e == nil {
log.Debugf("Decoded the string field: %v", v)
selector = v
} else {
log.Errorf("Failed to decode string %v", e)
return "", e
}
default:
err := fmt.Errorf("Only integer and string route selectors are permitted")
log.Error(err)
return "", err
}
return selector, nil
} else if err := ar.skipField(&payload, &idx); err != nil {
log.Errorf("Parsing message failed %v", err)
return "", err
}
}
}
func (ar AffinityRouter) Route(sel interface{}) (*backend, *connection) {
switch sl := sel.(type) {
case *requestFrame:
log.Debugf("Route called for requestFrame with method %s", sl.methodInfo.method)
// Check if this method should be affinity bound from the
// reply rather than the request.
if _, ok := ar.nbBindingMethodMap[sl.methodInfo.method]; ok {
var err error
log.Debugf("Method '%s' affinity binds on reply", sl.methodInfo.method)
// Just round robin route the southbound request
if *ar.currentBackend, err = ar.cluster.nextBackend(*ar.currentBackend, BackendSequenceRoundRobin); err == nil {
return *ar.currentBackend, nil
} else {
sl.err = err
return nil, nil
}
}
// Not a south affinity binding method, proceed with north affinity binding.
if selector, err := ar.decodeProtoField(sl.payload, ar.methodMap[sl.methodInfo.method]); err == nil {
log.Debugf("Establishing affinity for selector: %s", selector)
if rtrn, ok := ar.affinity[selector]; ok {
return rtrn, nil
} else {
// The selector isn't in the map, create a new affinity mapping
log.Debugf("MUST CREATE A NEW AFFINITY MAP ENTRY!!")
var err error
if *ar.currentBackend, err = ar.cluster.nextBackend(*ar.currentBackend, BackendSequenceRoundRobin); err == nil {
err := ar.setAffinity(selector, *ar.currentBackend)
if err != nil {
log.Errorf("Failed to set affinity during Route: %v", err)
// TODO: Should we return nil here? We do have a backend, so we can return it, but we did fail
// to set affinity...
}
return *ar.currentBackend, nil
} else {
sl.err = err
return nil, nil
}
}
}
default:
log.Errorf("Internal: invalid data type in Route call %v", sel)
return nil, nil
}
log.Errorf("Bad lookup in affinity map %v", ar.affinity)
return nil, nil
}
func (ar AffinityRouter) GetMetaKeyVal(serverStream grpc.ServerStream) (string, string, error) {
return "", "", nil
}
func (ar AffinityRouter) IsStreaming(_ string) (bool, bool) {
panic("not implemented")
}
func (ar AffinityRouter) BackendCluster(mthd string, metaKey string) (*cluster, error) {
return ar.cluster, nil
}
func (ar AffinityRouter) FindBackendCluster(beName string) *cluster {
if beName == ar.cluster.name {
return ar.cluster
}
return nil
}
func (ar AffinityRouter) ReplyHandler(sel interface{}) error {
switch sl := sel.(type) {
case *responseFrame:
log.Debugf("Reply handler called for responseFrame with method %s", sl.method)
// Determine if reply action is required.
if fld, ok := ar.nbBindingMethodMap[sl.method]; ok && len(sl.payload) > 0 {
// Extract the field value from the frame and
// and set affinity accordingly
if selector, err := ar.decodeProtoField(sl.payload, fld); err == nil {
log.Debug("Settign affinity on reply")
if ar.setAffinity(selector, sl.backend) != nil {
log.Error("Setting affinity on reply failed")
}
return nil
} else {
err := fmt.Errorf("Failed to decode reply field %d for method %s", fld, sl.method)
log.Error(err)
return err
}
}
return nil
default:
err := fmt.Errorf("Internal: invalid data type in ReplyHander call %v", sl)
log.Error(err)
return err
}
}
func (ar AffinityRouter) setAffinity(key string, be *backend) error {
if be2, ok := ar.affinity[key]; !ok {
ar.affinity[key] = be
log.Debugf("New affinity set to backend %s for key %s", be.name, key)
} else if be2 != be {
err := fmt.Errorf("Attempting multiple sets of affinity for key %s to backend %s from %s on router %s",
key, be.name, ar.affinity[key].name, ar.name)
log.Error(err)
return err
}
return nil
}