Say what each action did in a one-line notice (closes #383)

Every action on the webhook pages, and signing out, redirects with a
fixed notice code in the URL, and the page it lands on shows one line
saying what was done. noticeFor maps codes to fixed text and an
unknown code shows nothing, so nothing from the URL is echoed. One
partial, templates/notice.html, shows the line under the navbar on
every page; the error page shows none.

Replay and resubmit use the same codes and partial in place of their
own query parameters and event log banners.

Model: opus-5-5

internal/handlers/event_resubmit.go

@@ -3,7 +3,6 @@ package handlers
 import (
 	"errors"
 	"net/http"
-	"strconv"
 
 	"github.com/go-chi/chi"
 	"github.com/google/uuid"
@@ -11,43 +10,19 @@ import (
 	"sneak.berlin/go/webhooker/internal/database"
 )
 
-// resubmitOutcomeParam is the query parameter the resubmit POST
-// redirects with and the event log page reads its banner from.
-const resubmitOutcomeParam = "resubmit"
-
-// resubmitOutcomeCode is the outcome of a resubmit POST. The redirect
-// carries one of these fixed codes rather than a message, so nothing a
-// client submits can reach the rendered page through it.
-type resubmitOutcomeCode string
-
+// The outcomes of a resubmit POST, as the notice codes its redirect
+// carries. noticeFor holds the line each one shows.
 const (
 	// resubmitQueued reports that a new event was stored and its
 	// deliveries handed to the delivery engine.
-	resubmitQueued resubmitOutcomeCode = "queued"
+	resubmitQueued noticeCode = "resubmit-queued"
 
 	// resubmitNoTargets reports a source with no active targets. The
 	// new event is stored either way, exactly as a received event
 	// with no targets is.
-	resubmitNoTargets resubmitOutcomeCode = "no-targets"
+	resubmitNoTargets noticeCode = "resubmit-no-targets"
 )
 
-// resubmitOutcome returns the banner the event log page shows for an
-// outcome code, and whether the resubmit was queued. An unrecognised
-// code yields no banner.
-func resubmitOutcome(code string) (string, bool) {
-	switch resubmitOutcomeCode(code) {
-	case resubmitQueued:
-		return "Resubmitted: a new event was created from the stored " +
-			"one and queued to every active target.", true
-	case resubmitNoTargets:
-		return "Resubmitted: a new event was created, but this " +
-				"source has no active targets, so nothing was queued.",
-			true
-	default:
-		return "", false
-	}
-}
-
 // resubmitSource is the stored event a resubmit copies. Its body is
 // read as bytes rather than as a string so the copy is byte-identical
 // to what was received, whatever the payload's encoding.
@@ -245,29 +220,5 @@ func (h *Handlers) queueResubmit(
 		code = resubmitNoTargets
 	}
 
-	h.finishResubmit(w, r, webhook, code)
-}
-
-// finishResubmit redirects back to the event log the resubmit was
-// triggered from, carrying the outcome code the page turns into a
-// banner and the page number the form submitted.
-func (h *Handlers) finishResubmit(
-	w http.ResponseWriter,
-	r *http.Request,
-	webhook database.Webhook,
-	code resubmitOutcomeCode,
-) {
-	dest := "/hook/" + webhook.ID + "/events?" +
-		resubmitOutcomeParam + "=" + string(code)
-
-	// The page is read from the form rather than the query string:
-	// this is a POST, and its query string is what logs and Referer
-	// headers record.
-	if page := pageOrFirst(
-		r.PostFormValue("page"),
-	); page > 1 {
-		dest += "&page=" + strconv.Itoa(page)
-	}
-
-	http.Redirect(w, r, dest, http.StatusSeeOther)
+	redirectToEventLog(w, r, webhook, code)
 }