| package config |
| |
| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you 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. |
| */ |
| |
| import ( |
| "bytes" |
| "fmt" |
| "math" |
| "os" |
| "os/exec" |
| "path/filepath" |
| "time" |
| ) |
| |
| // StaticAppData encapsulates data about the app available at startup |
| type StaticAppData struct { |
| StartTime time.Time |
| GitRevision string |
| FreeMemoryMB uint64 |
| Version string |
| WorkingDir string |
| Name string |
| BuildTimestamp string |
| Hostname string |
| UserAgent string |
| } |
| |
| // getStaticAppData returns app data available at start time. |
| // This should be called immediately, as it includes calculating when the app was started. |
| func GetStaticAppData(version, gitRevision, buildTimestamp string) (StaticAppData, error) { |
| var d StaticAppData |
| var err error |
| d.StartTime = time.Now() |
| d.GitRevision = gitRevision |
| d.FreeMemoryMB = math.MaxUint64 // TODO remove if/when nothing needs this |
| d.Version = version |
| if d.WorkingDir, err = os.Getwd(); err != nil { |
| return StaticAppData{}, err |
| } |
| d.Name = os.Args[0] |
| d.BuildTimestamp = buildTimestamp |
| if d.Hostname, err = getHostNameWithoutDomain(); err != nil { |
| return StaticAppData{}, err |
| } |
| |
| d.UserAgent = fmt.Sprintf("%s/%s", filepath.Base(d.Name), d.Version) |
| return d, nil |
| } |
| |
| // getHostNameWithoutDomain returns the machine hostname, without domain information. |
| // Modified from http://stackoverflow.com/a/34331660/292623 |
| func getHostNameWithoutDomain() (string, error) { |
| cmd := exec.Command("/bin/hostname", "-s") |
| var out bytes.Buffer |
| cmd.Stdout = &out |
| err := cmd.Run() |
| if err != nil { |
| return "", err |
| } |
| hostname := out.String() |
| if len(hostname) < 1 { |
| return "", fmt.Errorf("OS returned empty hostname") |
| } |
| hostname = hostname[:len(hostname)-1] // removing EOL |
| return hostname, nil |
| } |