sslobodr | 392ebd5 | 2019-01-18 12:41:49 -0500 | [diff] [blame^] | 1 | /* |
| 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 | // gRPC affinity router with active/active backends |
| 17 | |
| 18 | package afrouter |
| 19 | |
| 20 | import ( |
| 21 | "fmt" |
| 22 | "errors" |
| 23 | "google.golang.org/grpc" |
| 24 | "google.golang.org/grpc/metadata" |
| 25 | "github.com/opencord/voltha-go/common/log" |
| 26 | ) |
| 27 | |
| 28 | const NoMeta = "nometa" |
| 29 | |
| 30 | type MethodRouter struct { |
| 31 | name string |
| 32 | service string |
| 33 | mthdRt map[string]map[string]Router // map of [metadata][method] |
| 34 | } |
| 35 | |
| 36 | func newMethodRouter(config *RouterConfig) (Router, error) { |
| 37 | mr := MethodRouter{name:config.Name,service:config.ProtoService,mthdRt:make(map[string]map[string]Router)} |
| 38 | mr.mthdRt[NoMeta] = make(map[string]Router) // For routes not needing metadata (all expcept binding at this time) |
| 39 | if len(config.Routes) == 0 { |
| 40 | return nil, errors.New(fmt.Sprintf("Router %s must have at least one route", config.Name)) |
| 41 | } |
| 42 | for _,rtv := range(config.Routes) { |
| 43 | var idx1 string |
| 44 | r,err := newRouter(config, &rtv) |
| 45 | if err != nil { |
| 46 | return nil, err |
| 47 | } |
| 48 | if rtv.Type == "binding" { |
| 49 | idx1 = rtv.Binding.Field |
| 50 | if _,ok := mr.mthdRt[idx1]; ok == false { // /First attempt on this key |
| 51 | mr.mthdRt[idx1] = make(map[string]Router) |
| 52 | } |
| 53 | } else { |
| 54 | idx1 = NoMeta |
| 55 | } |
| 56 | switch len(rtv.Methods) { |
| 57 | case 0: |
| 58 | return nil, errors.New(fmt.Sprintf("Route for router %s must have at least one method", config.Name)) |
| 59 | case 1: |
| 60 | if rtv.Methods[0] == "*" { |
| 61 | return r, nil |
| 62 | } else { |
| 63 | log.Debugf("Setting router '%s' for single method '%s'",r.Name(),rtv.Methods[0]) |
| 64 | if _,ok := mr.mthdRt[""][rtv.Methods[0]]; ok == false { |
| 65 | mr.mthdRt[idx1][rtv.Methods[0]] = r |
| 66 | } else { |
| 67 | err := errors.New(fmt.Sprintf("Attempt to define method %s for 2 routes: %s & %s", rtv.Methods[0], |
| 68 | r.Name(), mr.mthdRt[idx1][rtv.Methods[0]].Name())) |
| 69 | log.Debug(err) |
| 70 | return mr, err |
| 71 | } |
| 72 | } |
| 73 | default: |
| 74 | for _,m := range(rtv.Methods) { |
| 75 | log.Debugf("Setting router '%s' for method '%s'",r.Name(),m) |
| 76 | if _,ok := mr.mthdRt[idx1][m]; ok == false { |
| 77 | mr.mthdRt[idx1][m] = r |
| 78 | } else { |
| 79 | err := errors.New(fmt.Sprintf("Attempt to define method %s for 2 routes: %s & %s", rtv.Methods[0], |
| 80 | r.Name(), mr.mthdRt[idx1][m].Name())) |
| 81 | log.Debug(err) |
| 82 | return mr, err |
| 83 | } |
| 84 | } |
| 85 | } |
| 86 | } |
| 87 | |
| 88 | return mr, nil |
| 89 | } |
| 90 | |
| 91 | func (mr MethodRouter) Name() string { |
| 92 | return mr.name |
| 93 | } |
| 94 | |
| 95 | func (mr MethodRouter) Service() string { |
| 96 | return mr.service |
| 97 | } |
| 98 | |
| 99 | func (mr MethodRouter) GetMetaKeyVal(serverStream grpc.ServerStream) (string,string,error) { |
| 100 | var rtrnK string = NoMeta |
| 101 | var rtrnV string = "" |
| 102 | |
| 103 | // Get the metadata from the server stream |
| 104 | md, ok := metadata.FromIncomingContext(serverStream.Context()) |
| 105 | if !ok { |
| 106 | return rtrnK, rtrnV, errors.New("Could not get a server stream metadata") |
| 107 | } |
| 108 | |
| 109 | // Determine if one of the method routing keys exists in the metadata |
| 110 | for k,_ := range(mr.mthdRt) { |
| 111 | if _,ok := md[k]; ok == true { |
| 112 | rtrnV = md[k][0] |
| 113 | rtrnK = k |
| 114 | break |
| 115 | } |
| 116 | } |
| 117 | return rtrnK,rtrnV,nil |
| 118 | |
| 119 | } |
| 120 | |
| 121 | func (mr MethodRouter) ReplyHandler(sel interface{}) error { |
| 122 | switch sl := sel.(type) { |
| 123 | case *sbFrame: |
| 124 | if r,ok := mr.mthdRt[NoMeta][sl.method]; ok == true { |
| 125 | return r.ReplyHandler(sel) |
| 126 | } |
| 127 | // TODO: this case should also be an error |
| 128 | default: //TODO: This should really be a big error |
| 129 | // A reply handler should only be called on the sbFrame |
| 130 | return nil |
| 131 | } |
| 132 | return nil |
| 133 | } |
| 134 | |
| 135 | func (mr MethodRouter) Route(sel interface{}) *backend { |
| 136 | switch sl := sel.(type) { |
| 137 | case *nbFrame: |
| 138 | if r,ok := mr.mthdRt[sl.metaKey][sl.mthdSlice[REQ_METHOD]]; ok == true { |
| 139 | return r.Route(sel) |
| 140 | } |
| 141 | log.Errorf("Attept to route on non-existent method '%s'", sl.mthdSlice[REQ_METHOD]) |
| 142 | return nil |
| 143 | default: |
| 144 | return nil |
| 145 | } |
| 146 | return nil |
| 147 | } |
| 148 | |
| 149 | func (mr MethodRouter) BackendCluster(mthd string, metaKey string) (*backendCluster,error) { |
| 150 | if r,ok := mr.mthdRt[metaKey][mthd]; ok == true { |
| 151 | return r.BackendCluster(mthd, metaKey) |
| 152 | } |
| 153 | err := errors.New(fmt.Sprintf("No backend cluster exists for method '%s' using meta key '%s'", mthd,metaKey)) |
| 154 | log.Error(err) |
| 155 | return nil, err |
| 156 | } |
| 157 | |
| 158 | func (mr MethodRouter) FindBackendCluster(beName string) *backendCluster { |
| 159 | for _,meta := range mr.mthdRt { |
| 160 | for _,r := range meta { |
| 161 | if rtrn := r.FindBackendCluster(beName); rtrn != nil { |
| 162 | return rtrn |
| 163 | } |
| 164 | } |
| 165 | } |
| 166 | return nil |
| 167 | } |