feat(idlesleep): support container dependencies, including custom and docker depends_on, code refactor

internal/idlewatcher/handle_http.go

@@ -1,8 +1,6 @@
 package idlewatcher
 
 import (
-	"context"
-	"errors"
 	"net/http"
 	"strconv"
 	"time"
@@ -38,10 +36,6 @@ func (w *Watcher) ServeHTTP(rw http.ResponseWriter, r *http.Request) {
 		return
 	default:
 		f := &ForceCacheControl{expires: w.expires().Format(http.TimeFormat), ResponseWriter: rw}
-		w, ok := watcherMap[w.Key()] // could've been reloaded
-		if !ok {
-			return
-		}
 		w.rp.ServeHTTP(f, r)
 	}
 }
@@ -50,6 +44,14 @@ func isFaviconPath(path string) bool {
 	return path == "/favicon.ico"
 }
 
+func (w *Watcher) redirectToStartEndpoint(rw http.ResponseWriter, r *http.Request) {
+	uri := "/"
+	if w.cfg.StartEndpoint != "" {
+		uri = w.cfg.StartEndpoint
+	}
+	http.Redirect(rw, r, uri, http.StatusTemporaryRedirect)
+}
+
 func (w *Watcher) wakeFromHTTP(rw http.ResponseWriter, r *http.Request) (shouldNext bool) {
 	w.resetIdleTimer()
 
@@ -92,7 +94,7 @@ func (w *Watcher) wakeFromHTTP(rw http.ResponseWriter, r *http.Request) (shouldN
 
 	ctx := r.Context()
 	if w.cancelled(ctx) {
-		gphttp.ServerError(rw, r, context.Cause(ctx), http.StatusServiceUnavailable)
+		w.redirectToStartEndpoint(rw, r)
 		return false
 	}
 
@@ -103,17 +105,19 @@ func (w *Watcher) wakeFromHTTP(rw http.ResponseWriter, r *http.Request) (shouldN
 		return false
 	}
 
-	var ready bool
-
 	for {
 		w.resetIdleTimer()
 
 		if w.cancelled(ctx) {
-			gphttp.ServerError(rw, r, context.Cause(ctx), http.StatusServiceUnavailable)
+			w.redirectToStartEndpoint(rw, r)
 			return false
 		}
 
-		w, ready, err = checkUpdateState(w.Key())
+		if !w.waitStarted(ctx) {
+			return false
+		}
+
+		ready, err := w.checkUpdateState()
 		if err != nil {
 			gphttp.ServerError(rw, r, err)
 			return false