services/boot/server.go

   1 package main
   2
   3 import (
   4         "encoding/json"
   5         "flag"
   6         "log"
   7         "net/http"
   8         "os"
   9         "strconv"
  10         "time"
  11
  12         "git.curoverse.com/arvados.git/sdk/go/config"
  13 )
  14
  15 const defaultCfgPath = "/etc/arvados/boot/boot.yml"
  16
  17 var cfg Config
  18
  19 func main() {
  20         cfgPath := flag.String("config", defaultCfgPath, "`path` to config file")
  21         flag.Parse()
  22
  23         if err := config.LoadFile(&cfg, *cfgPath); os.IsNotExist(err) && *cfgPath == defaultCfgPath {
  24                 log.Printf("WARNING: No config file specified or found, starting fresh!")
  25         } else if err != nil {
  26                 log.Fatal(err)
  27         }
  28         cfg.SetDefaults()
  29         go func() {
  30                 log.Printf("starting server at %s", cfg.WebListen)
  31                 log.Fatal(http.ListenAndServe(cfg.WebListen, stack(logger, apiOrAssets)))
  32         }()
  33         go func() {
  34                 ticker := time.NewTicker(5 * time.Second)
  35                 for {
  36                         runTasks(&cfg, ctlTasks)
  37                         <-ticker.C
  38                 }
  39         }()
  40         <-(chan struct{})(nil)
  41 }
  42
  43 type middleware func(http.Handler) http.Handler
  44
  45 var notFound = http.NotFoundHandler()
  46
  47 // returns a handler that implements a stack of middlewares.
  48 func stack(m ...middleware) http.Handler {
  49         if len(m) == 0 {
  50                 return notFound
  51         }
  52         return m[0](stack(m[1:]...))
  53 }
  54
  55 // logs each request.
  56 func logger(next http.Handler) http.Handler {
  57         return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
  58                 t := time.Now()
  59                 next.ServeHTTP(w, r)
  60                 log.Printf("%.6f %q %q %q", time.Since(t).Seconds(), r.RemoteAddr, r.Method, r.URL.Path)
  61         })
  62 }
  63
  64 // dispatches /api/ to the API stack, everything else to the static
  65 // assets stack.
  66 func apiOrAssets(next http.Handler) http.Handler {
  67         mux := http.NewServeMux()
  68         mux.Handle("/api/", stack(apiHeaders, apiRoutes))
  69         mux.Handle("/", http.FileServer(assetFS()))
  70         return mux
  71 }
  72
  73 // adds response headers suitable for API responses
  74 func apiHeaders(next http.Handler) http.Handler {
  75         return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
  76                 w.Header().Set("Content-Type", "application/json")
  77                 next.ServeHTTP(w, r)
  78         })
  79 }
  80
  81 // dispatches API routes
  82 func apiRoutes(http.Handler) http.Handler {
  83         mux := http.NewServeMux()
  84         mux.HandleFunc("/api/ping", func(w http.ResponseWriter, r *http.Request) {
  85                 json.NewEncoder(w).Encode(map[string]interface{}{"time": time.Now().UTC()})
  86         })
  87         mux.HandleFunc("/api/tasks/ctl", func(w http.ResponseWriter, r *http.Request) {
  88                 timeout := time.Minute
  89                 if v, err := strconv.ParseInt(r.FormValue("timeout"), 10, 64); err == nil {
  90                         timeout = time.Duration(v) * time.Second
  91                 }
  92                 if v, err := strconv.ParseInt(r.FormValue("newerThan"), 10, 64); err == nil {
  93                         TaskState.Wait(version(v), timeout, r.Context())
  94                 }
  95                 rep, v := report(ctlTasks)
  96                 json.NewEncoder(w).Encode(map[string]interface{}{
  97                         "Version": v,
  98                         "Tasks":   rep,
  99                 })
 100         })
 101         mux.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
 102                 w.WriteHeader(http.StatusNotFound)
 103                 json.NewEncoder(w).Encode(map[string]string{"error": "not found"})
 104         })
 105         return mux
 106 }