| // Copyright 2017 The LUCI 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 utils |
| |
| import ( |
| "context" |
| "fmt" |
| |
| "go.chromium.org/luci/server/auth/signing" |
| ) |
| |
| // ServiceVersion returns a string that identifies the app and the version. |
| // |
| // It is put in some server responses. The function extracts this information |
| // from the given signer. |
| // |
| // This function almost never returns errors. It can return an error only when |
| // called for the first time during the process lifetime. It gets cached after |
| // first successful return. |
| func ServiceVersion(c context.Context, s signing.Signer) (string, error) { |
| inf, err := s.ServiceInfo(c) // cached |
| if err != nil { |
| return "", err |
| } |
| return fmt.Sprintf("%s/%s", inf.AppID, inf.AppVersion), nil |
| } |
