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Scott Bakere7144bc2019-10-01 14:16:47 -07001/*
2 * Copyright 2018-present Open Networking Foundation
3
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7
8 * http://www.apache.org/licenses/LICENSE-2.0
9
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package afrouter
18
19import (
20 "errors"
21 "fmt"
22 "github.com/golang/protobuf/proto"
23 "github.com/opencord/voltha-go/common/log"
24 "google.golang.org/grpc"
25 "regexp"
26 "strconv"
27)
28
29// TODO: Used in multiple routers, should move to common file
30const (
31 PKG_MTHD_PKG int = 1
32 PKG_MTHD_MTHD int = 2
33)
34
35type AffinityRouter struct {
36 name string
37 association associationType
38 routingField string
39 grpcService string
40 methodMap map[string]byte
41 nbBindingMethodMap map[string]byte
42 cluster *cluster
43 affinity map[string]*backend
44 currentBackend **backend
45}
46
47func newAffinityRouter(rconf *RouterConfig, config *RouteConfig) (Router, error) {
48 var err error = nil
49 var rtrn_err = false
50 var pkg_re = regexp.MustCompile(`^(\.[^.]+\.)(.+)$`)
51 // Validate the configuration
52
53 // A name must exist
54 if config.Name == "" {
55 log.Error("A router 'name' must be specified")
56 rtrn_err = true
57 }
58
59 if rconf.ProtoPackage == "" {
60 log.Error("A 'package' must be specified")
61 rtrn_err = true
62 }
63
64 if rconf.ProtoService == "" {
65 log.Error("A 'service' must be specified")
66 rtrn_err = true
67 }
68
69 //if config.RouteField == "" {
70 // log.Error("A 'routing_field' must be specified")
71 // rtrn_err = true
72 //}
73
74 // TODO The overrieds section is currently not being used
75 // so the router will route all methods based on the
76 // routing_field. This needs to be added so that methods
77 // can have different routing fields.
78 var bptr *backend
79 bptr = nil
80 dr := AffinityRouter{
81 name: config.Name,
82 grpcService: rconf.ProtoService,
83 affinity: make(map[string]*backend),
84 methodMap: make(map[string]byte),
85 nbBindingMethodMap: make(map[string]byte),
86 currentBackend: &bptr,
87 }
88 // An association must exist
89 dr.association = config.Association
90 if dr.association == AssociationUndefined {
91 log.Error("An association must be specified")
92 rtrn_err = true
93 }
94
95 // Build the routing structure based on the loaded protobuf
96 // descriptor file and the config information.
97 type key struct {
98 method string
99 field string
100 }
101 var fieldNumberLookup = make(map[key]byte)
102 for _, f := range rconf.protoDescriptor.File {
103 // Build a temporary map of message types by name.
104 for _, m := range f.MessageType {
105 for _, fld := range m.Field {
106 log.Debugf("Processing message '%s', field '%s'", *m.Name, *fld.Name)
107 fieldNumberLookup[key{*m.Name, *fld.Name}] = byte(*fld.Number)
108 }
109 }
110 }
111 for _, f := range rconf.protoDescriptor.File {
112 if *f.Package == rconf.ProtoPackage {
113 for _, s := range f.Service {
114 if *s.Name == rconf.ProtoService {
115 log.Debugf("Loading package data '%s' for service '%s' for router '%s'", *f.Package, *s.Name, dr.name)
116 // Now create a map keyed by method name with the value being the
117 // field number of the route selector.
118 var ok bool
119 for _, m := range s.Method {
120 // Find the input type in the messages and extract the
121 // field number and save it for future reference.
122 log.Debugf("Processing method '%s'", *m.Name)
123 // Determine if this is a method we're supposed to be processing.
124 if needMethod(*m.Name, config) {
125 log.Debugf("Enabling method '%s'", *m.Name)
126 pkg_methd := pkg_re.FindStringSubmatch(*m.InputType)
127 if pkg_methd == nil {
128 log.Errorf("Regular expression didn't match input type '%s'", *m.InputType)
129 rtrn_err = true
130 }
131 // The input type has the package name prepended to it. Remove it.
132 //in := (*m.InputType)[len(rconf.ProtoPackage)+2:]
133 in := pkg_methd[PKG_MTHD_MTHD]
134 dr.methodMap[*m.Name], ok = fieldNumberLookup[key{in, config.RouteField}]
135 if !ok {
136 log.Errorf("Method '%s' has no field named '%s' in it's parameter message '%s'",
137 *m.Name, config.RouteField, in)
138 rtrn_err = true
139 }
140 }
141 // The sb method is always included in the methods so we can check it here too.
142 if needNbBindingMethod(*m.Name, config) {
143 log.Debugf("Enabling southbound method '%s'", *m.Name)
144 // The output type has the package name prepended to it. Remove it.
145 out := (*m.OutputType)[len(rconf.ProtoPackage)+2:]
146 dr.nbBindingMethodMap[*m.Name], ok = fieldNumberLookup[key{out, config.RouteField}]
147 if !ok {
148 log.Errorf("Method '%s' has no field named '%s' in it's parameter message '%s'",
149 *m.Name, config.RouteField, out)
150 rtrn_err = true
151 }
152 }
153 }
154 }
155 }
156 }
157 }
158
159 // Create the backend cluster or link to an existing one
160 ok := true
161 if dr.cluster, ok = clusters[config.backendCluster.Name]; !ok {
162 if dr.cluster, err = newBackendCluster(config.backendCluster); err != nil {
163 log.Errorf("Could not create a backend for router %s", config.Name)
164 rtrn_err = true
165 }
166 }
167
168 if rtrn_err {
169 return dr, errors.New(fmt.Sprintf("Failed to create a new router '%s'", dr.name))
170 }
171
172 return dr, nil
173}
174
175func needNbBindingMethod(mthd string, conf *RouteConfig) bool {
176 for _, m := range conf.NbBindingMethods {
177 if mthd == m {
178 return true
179 }
180 }
181 return false
182}
183
184// TODO: Used in multiple routers, should move to common file
185func needMethod(mthd string, conf *RouteConfig) bool {
186 for _, m := range conf.Methods {
187 if mthd == m {
188 return true
189 }
190 }
191 return false
192}
193
194func (ar AffinityRouter) Service() string {
195 return ar.grpcService
196}
197
198func (ar AffinityRouter) Name() string {
199 return ar.name
200}
201
202func (ar AffinityRouter) skipField(data *[]byte, idx *int) error {
203 switch (*data)[*idx] & 3 {
204 case 0: // Varint
205 // skip the field number/type
206 *idx++
207 // if the msb is set, then more bytes to follow
208 for (*data)[*idx] >= 128 {
209 *idx++
210 }
211 // the last byte doesn't have the msb set
212 *idx++
213 case 1: // 64 bit
214 *idx += 9
215 case 2: // Length delimited
216 *idx++
217 b := proto.NewBuffer((*data)[*idx:])
218 t, _ := b.DecodeVarint()
219 *idx += int(t) + 1
220 case 3: // Deprecated
221 case 4: // Deprecated
222 case 5: // 32 bit
223 *idx += 5
224 }
225 return nil
226}
227
228func (ar AffinityRouter) decodeProtoField(payload []byte, fieldId byte) (string, error) {
229 idx := 0
230 b := proto.NewBuffer([]byte{})
231 //b.DebugPrint("The Buffer", payload)
232 for { // Find the route selector field
233 log.Debugf("Decoding afinity value attributeNumber: %d from %v at index %d", fieldId, payload, idx)
234 log.Debugf("Attempting match with payload: %d, methodTable: %d", payload[idx], fieldId)
235 if payload[idx]>>3 == fieldId {
236 log.Debugf("Method match with payload: %d, methodTable: %d", payload[idx], fieldId)
237 // TODO: Consider supporting other selector types.... Way, way in the future
238 // ok, the future is now, support strings as well... ugh.
239 var selector string
240 switch payload[idx] & 3 {
241 case 0: // Integer
242 b.SetBuf(payload[idx+1:])
243 v, e := b.DecodeVarint()
244 if e == nil {
245 log.Debugf("Decoded the ing field: %v", v)
246 selector = strconv.Itoa(int(v))
247 } else {
248 log.Errorf("Failed to decode varint %v", e)
249 return "", e
250 }
251 case 2: // Length delimited AKA string
252 b.SetBuf(payload[idx+1:])
253 v, e := b.DecodeStringBytes()
254 if e == nil {
255 log.Debugf("Decoded the string field: %v", v)
256 selector = v
257 } else {
258 log.Errorf("Failed to decode string %v", e)
259 return "", e
260 }
261 default:
262 err := errors.New(fmt.Sprintf("Only integer and string route selectors are permitted"))
263 log.Error(err)
264 return "", err
265 }
266 return selector, nil
267 } else if err := ar.skipField(&payload, &idx); err != nil {
268 log.Errorf("Parsing message failed %v", err)
269 return "", err
270 }
271 }
272}
273
274func (ar AffinityRouter) Route(sel interface{}) (*backend, *connection) {
275 switch sl := sel.(type) {
276 case *requestFrame:
277 log.Debugf("Route called for requestFrame with method %s", sl.methodInfo.method)
278 // Check if this method should be affinity bound from the
279 // reply rather than the request.
280 if _, ok := ar.nbBindingMethodMap[sl.methodInfo.method]; ok {
281 var err error
282 log.Debugf("Method '%s' affinity binds on reply", sl.methodInfo.method)
283 // Just round robin route the southbound request
284 if *ar.currentBackend, err = ar.cluster.nextBackend(*ar.currentBackend, BackendSequenceRoundRobin); err == nil {
285 return *ar.currentBackend, nil
286 } else {
287 sl.err = err
288 return nil, nil
289 }
290 }
291 // Not a south affinity binding method, proceed with north affinity binding.
292 if selector, err := ar.decodeProtoField(sl.payload, ar.methodMap[sl.methodInfo.method]); err == nil {
293 log.Debugf("Establishing affinity for selector: %s", selector)
294 if rtrn, ok := ar.affinity[selector]; ok {
295 return rtrn, nil
296 } else {
297 // The selector isn't in the map, create a new affinity mapping
298 log.Debugf("MUST CREATE A NEW AFFINITY MAP ENTRY!!")
299 var err error
300 if *ar.currentBackend, err = ar.cluster.nextBackend(*ar.currentBackend, BackendSequenceRoundRobin); err == nil {
301 ar.setAffinity(selector, *ar.currentBackend)
302 //ar.affinity[selector] = *ar.currentBackend
303 //log.Debugf("New affinity set to backend %s",(*ar.currentBackend).name)
304 return *ar.currentBackend, nil
305 } else {
306 sl.err = err
307 return nil, nil
308 }
309 }
310 }
311 default:
312 log.Errorf("Internal: invalid data type in Route call %v", sel)
313 return nil, nil
314 }
315 log.Errorf("Bad lookup in affinity map %v", ar.affinity)
316 return nil, nil
317}
318
319func (ar AffinityRouter) GetMetaKeyVal(serverStream grpc.ServerStream) (string, string, error) {
320 return "", "", nil
321}
322
323func (ar AffinityRouter) IsStreaming(_ string) (bool, bool) {
324 panic("not implemented")
325}
326
327func (ar AffinityRouter) BackendCluster(mthd string, metaKey string) (*cluster, error) {
328 return ar.cluster, nil
329}
330
331func (ar AffinityRouter) FindBackendCluster(beName string) *cluster {
332 if beName == ar.cluster.name {
333 return ar.cluster
334 }
335 return nil
336}
337
338func (ar AffinityRouter) ReplyHandler(sel interface{}) error {
339 switch sl := sel.(type) {
340 case *responseFrame:
341 log.Debugf("Reply handler called for responseFrame with method %s", sl.method)
342 // Determine if reply action is required.
343 if fld, ok := ar.nbBindingMethodMap[sl.method]; ok && len(sl.payload) > 0 {
344 // Extract the field value from the frame and
345 // and set affinity accordingly
346 if selector, err := ar.decodeProtoField(sl.payload, fld); err == nil {
347 log.Debug("Settign affinity on reply")
348 if ar.setAffinity(selector, sl.backend) != nil {
349 log.Error("Setting affinity on reply failed")
350 }
351 return nil
352 } else {
353 err := errors.New(fmt.Sprintf("Failed to decode reply field %d for method %s", fld, sl.method))
354 log.Error(err)
355 return err
356 }
357 }
358 return nil
359 default:
360 err := errors.New(fmt.Sprintf("Internal: invalid data type in ReplyHander call %v", sl))
361 log.Error(err)
362 return err
363 }
364}
365
366func (ar AffinityRouter) setAffinity(key string, be *backend) error {
367 if be2, ok := ar.affinity[key]; !ok {
368 ar.affinity[key] = be
369 log.Debugf("New affinity set to backend %s for key %s", be.name, key)
370 } else if be2 != be {
371 err := errors.New(fmt.Sprintf("Attempting multiple sets of affinity for key %s to backend %s from %s on router %s",
372 key, be.name, ar.affinity[key].name, ar.name))
373 log.Error(err)
374 return err
375 }
376 return nil
377}