mirror of https://github.com/perkeep/perkeep.git
99 lines
2.7 KiB
Go
99 lines
2.7 KiB
Go
/*
|
|
Copyright 2014 The Perkeep 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.
|
|
*/
|
|
|
|
// The hello application serves as an example on how to make stand-alone
|
|
// server applications, interacting with a Perkeep server.
|
|
package main // import "perkeep.org/app/hello"
|
|
|
|
import (
|
|
"context"
|
|
"flag"
|
|
"fmt"
|
|
"log"
|
|
"net/http"
|
|
"os"
|
|
"runtime"
|
|
|
|
"perkeep.org/pkg/app"
|
|
"perkeep.org/pkg/buildinfo"
|
|
"perkeep.org/pkg/webserver"
|
|
)
|
|
|
|
var (
|
|
flagVersion = flag.Bool("version", false, "show version")
|
|
)
|
|
|
|
// config is used to unmarshal the application configuration JSON
|
|
// that we get from Perkeep when we request it at $CAMLI_APP_CONFIG_URL.
|
|
type config struct {
|
|
Word string `json:"word,omitempty"` // Argument printed after "Hello " in the helloHandler response.
|
|
}
|
|
|
|
func appConfig() *config {
|
|
configURL := os.Getenv("CAMLI_APP_CONFIG_URL")
|
|
if configURL == "" {
|
|
log.Fatalf("Hello application needs a CAMLI_APP_CONFIG_URL env var")
|
|
}
|
|
cl, err := app.Client()
|
|
if err != nil {
|
|
log.Fatalf("could not get a client to fetch extra config: %v", err)
|
|
}
|
|
conf := &config{}
|
|
if err := cl.GetJSON(context.TODO(), configURL, conf); err != nil {
|
|
log.Fatalf("could not get app config at %v: %v", configURL, err)
|
|
}
|
|
return conf
|
|
}
|
|
|
|
type helloHandler struct {
|
|
who string // who to say hello to.
|
|
}
|
|
|
|
func (h *helloHandler) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
|
|
rw.Header().Set("Content-Type", "text/plain; charset=utf-8")
|
|
rw.WriteHeader(200)
|
|
fmt.Fprintf(rw, "Hello %s\n", h.who)
|
|
}
|
|
|
|
func main() {
|
|
flag.Parse()
|
|
|
|
if *flagVersion {
|
|
fmt.Fprintf(os.Stderr, "hello version: %s\nGo version: %s (%s/%s)\n",
|
|
buildinfo.Summary(), runtime.Version(), runtime.GOOS, runtime.GOARCH)
|
|
return
|
|
}
|
|
|
|
log.Printf("Starting hello version %s; Go %s (%s/%s)", buildinfo.Summary(), runtime.Version(),
|
|
runtime.GOOS, runtime.GOARCH)
|
|
|
|
listenAddr, err := app.ListenAddress()
|
|
if err != nil {
|
|
log.Fatalf("Listen address: %v", err)
|
|
}
|
|
conf := appConfig()
|
|
ws := webserver.New()
|
|
ws.Handle("/", &helloHandler{who: conf.Word})
|
|
// TODO(mpl): handle status requests too. Perkeep will send an auth
|
|
// token in the extra config that should be used as the "password" for
|
|
// subsequent status requests.
|
|
if err := ws.Listen(listenAddr); err != nil {
|
|
log.Fatalf("Listen: %v", err)
|
|
}
|
|
|
|
ws.Serve()
|
|
}
|