khenaidoo | 5fc5cea | 2021-08-11 17:39:16 -0400 | [diff] [blame] | 1 | /* |
| 2 | * |
| 3 | * Copyright 2020 gRPC authors. |
| 4 | * |
| 5 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 6 | * you may not use this file except in compliance with the License. |
| 7 | * You may obtain a copy of the License at |
| 8 | * |
| 9 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 10 | * |
| 11 | * Unless required by applicable law or agreed to in writing, software |
| 12 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 13 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 14 | * See the License for the specific language governing permissions and |
| 15 | * limitations under the License. |
| 16 | * |
| 17 | */ |
| 18 | |
| 19 | // Package unix implements a resolver for unix targets. |
| 20 | package unix |
| 21 | |
| 22 | import ( |
| 23 | "fmt" |
| 24 | |
| 25 | "google.golang.org/grpc/internal/transport/networktype" |
| 26 | "google.golang.org/grpc/resolver" |
| 27 | ) |
| 28 | |
| 29 | const unixScheme = "unix" |
| 30 | const unixAbstractScheme = "unix-abstract" |
| 31 | |
| 32 | type builder struct { |
| 33 | scheme string |
| 34 | } |
| 35 | |
| 36 | func (b *builder) Build(target resolver.Target, cc resolver.ClientConn, _ resolver.BuildOptions) (resolver.Resolver, error) { |
| 37 | if target.Authority != "" { |
| 38 | return nil, fmt.Errorf("invalid (non-empty) authority: %v", target.Authority) |
| 39 | } |
khenaidoo | 5cb0d40 | 2021-12-08 14:09:16 -0500 | [diff] [blame] | 40 | |
| 41 | // gRPC was parsing the dial target manually before PR #4817, and we |
| 42 | // switched to using url.Parse() in that PR. To avoid breaking existing |
| 43 | // resolver implementations we ended up stripping the leading "/" from the |
| 44 | // endpoint. This obviously does not work for the "unix" scheme. Hence we |
| 45 | // end up using the parsed URL instead. |
| 46 | endpoint := target.URL.Path |
| 47 | if endpoint == "" { |
| 48 | endpoint = target.URL.Opaque |
| 49 | } |
| 50 | addr := resolver.Address{Addr: endpoint} |
khenaidoo | 5fc5cea | 2021-08-11 17:39:16 -0400 | [diff] [blame] | 51 | if b.scheme == unixAbstractScheme { |
| 52 | // prepend "\x00" to address for unix-abstract |
| 53 | addr.Addr = "\x00" + addr.Addr |
| 54 | } |
| 55 | cc.UpdateState(resolver.State{Addresses: []resolver.Address{networktype.Set(addr, "unix")}}) |
| 56 | return &nopResolver{}, nil |
| 57 | } |
| 58 | |
| 59 | func (b *builder) Scheme() string { |
| 60 | return b.scheme |
| 61 | } |
| 62 | |
| 63 | type nopResolver struct { |
| 64 | } |
| 65 | |
| 66 | func (*nopResolver) ResolveNow(resolver.ResolveNowOptions) {} |
| 67 | |
| 68 | func (*nopResolver) Close() {} |
| 69 | |
| 70 | func init() { |
| 71 | resolver.Register(&builder{scheme: unixScheme}) |
| 72 | resolver.Register(&builder{scheme: unixAbstractScheme}) |
| 73 | } |