mirror of https://github.com/docker/compose.git
86 lines
1.9 KiB
Go
86 lines
1.9 KiB
Go
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/*
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Copyright 2020 Docker Compose CLI authors
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Licensed under the Apache License, Version 2.0 (the "License");
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you may not use this file except in compliance with the License.
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You may obtain a copy of the License at
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http://www.apache.org/licenses/LICENSE-2.0
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Unless required by applicable law or agreed to in writing, software
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distributed under the License is distributed on an "AS IS" BASIS,
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WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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See the License for the specific language governing permissions and
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limitations under the License.
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*/
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package main
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import (
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"fmt"
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"io/ioutil"
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"log"
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"math/rand"
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"net"
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"net/http"
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"time"
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)
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func main() {
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rand.Seed(time.Now().UnixNano())
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fwd := &forwarder{"words", 8080}
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http.Handle("/words/", http.StripPrefix("/words", fwd))
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http.Handle("/", http.FileServer(http.Dir("static")))
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fmt.Println("Listening on port 80")
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err := http.ListenAndServe(":80", nil)
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if err != nil {
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fmt.Printf("Error while starting server: %v", err)
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}
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}
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type forwarder struct {
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host string
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port int
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}
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func (f *forwarder) ServeHTTP(w http.ResponseWriter, r *http.Request) {
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addrs, err := net.LookupHost(f.host)
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if err != nil {
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log.Println("Error", err)
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http.Error(w, err.Error(), 500)
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return
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}
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log.Printf("%s %d available ips: %v", r.URL.Path, len(addrs), addrs)
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ip := addrs[rand.Intn(len(addrs))]
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log.Printf("%s I choose %s", r.URL.Path, ip)
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url := fmt.Sprintf("http://%s:%d%s", ip, f.port, r.URL.Path)
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log.Printf("%s Calling %s", r.URL.Path, url)
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if err = copy(url, ip, w); err != nil {
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log.Println("Error", err)
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http.Error(w, err.Error(), 500)
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return
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}
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}
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func copy(url, ip string, w http.ResponseWriter) error {
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resp, err := http.Get(url)
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if err != nil {
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return err
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}
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w.Header().Set("source", ip)
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buf, err := ioutil.ReadAll(resp.Body)
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if err != nil {
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return err
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}
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_, err = w.Write(buf)
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return err
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}
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