Name each database target's archive for its webhook and target (closes #376)

Each database target now has its own archive file,
archive-WEBHOOKNAME-TARGETNAME-TARGETID.db, instead of one
archive-WEBHOOKID.db per webhook. delivery.ArchiveFileName builds the
name: each name is lowercased, keeps ASCII letters and digits, turns
every other run of characters into one dash, and is cut to 40
characters.

A change of webhook or target name renames its archive files under the
archive writer's lock, before the new name is saved, and back again if
the save fails. A rename never replaces a file: if one already has the
new name, the edit is refused. Deleting a target evicts only that
target's writer. Archive files are never deleted, and nothing looks for
files under the old name.

Model: opus-5-5

internal/delivery/engine_lifecycle_test.go

@@ -2,7 +2,6 @@ package delivery_test
 
 import (
 	"context"
-	"fmt"
 	"path/filepath"
 	"testing"
 	"time"
@@ -10,6 +9,7 @@ import (
 	"github.com/google/uuid"
 	"github.com/stretchr/testify/require"
 	"go.uber.org/fx"
+	"gorm.io/gorm/clause"
 	"sneak.berlin/go/webhooker/internal/database"
 	"sneak.berlin/go/webhooker/internal/delivery"
 )
@@ -272,22 +272,35 @@ func TestEngine_StopHookHonoursStopTimeout(t *testing.T) {
 	requireStopHookExpires(t, lc.hooks[0], "delivery engine")
 }
 
-// deliverToArchive runs one delivery to a database target through
-// the running engine and returns the webhook's archive file path.
-// The archive writer holds the file open afterwards.
-func deliverToArchive(t *testing.T, s iSetup) string {
+// deliverToArchive gives the setup's webhook a database target,
+// runs one delivery to it through the running engine, and returns
+// the target's ID and archive file path. The archive writer holds
+// the file open afterwards.
+func deliverToArchive(t *testing.T, s iSetup) (string, string) {
 	t.Helper()
 
+	iCreateWebhook(t, s.MainDB, s.WebhookID, "hook")
+
+	tgt := &database.Target{
+		WebhookID: s.WebhookID,
+		Name:      "archive",
+		Type:      database.TargetTypeDatabase,
+	}
+	require.NoError(
+		t, s.MainDB.Omit(clause.Associations).Create(tgt).Error,
+	)
+
 	deliveryID, task := seedLogTask(t, s)
+	task.TargetID = tgt.ID
 	task.TargetType = database.TargetTypeDatabase
 
 	s.Engine.Notify([]delivery.Task{task})
 
 	iWaitForDelivered(t, s.WebhookDB, deliveryID)
 
-	return filepath.Join(
+	return tgt.ID, filepath.Join(
 		filepath.Dir(s.DBMgr.DBPath(s.WebhookID)),
-		fmt.Sprintf("archive-%s.db", s.WebhookID),
+		"archive-hook-archive-"+tgt.ID+".db",
 	)
 }
 
@@ -304,7 +317,7 @@ func TestEngine_StopHookClosesArchives(t *testing.T) {
 
 	lc := startEngineViaHook(t, s.Engine)
 
-	path := deliverToArchive(t, s)
+	_, path := deliverToArchive(t, s)
 	require.FileExists(
 		t, path+"-wal",
 		"an open archive should have a -wal for the stop to remove",
@@ -338,7 +351,7 @@ func TestEngine_StopHookTimeoutLeavesArchivesOpen(t *testing.T) {
 
 	lc := startEngineViaHook(t, s.Engine)
 
-	deliverToArchive(t, s)
+	targetID, _ := deliverToArchive(t, s)
 
 	release := make(chan struct{})
 
@@ -352,7 +365,7 @@ func TestEngine_StopHookTimeoutLeavesArchivesOpen(t *testing.T) {
 	requireStopHookExpires(t, lc.hooks[0], "delivery engine")
 
 	require.True(
-		t, s.Engine.ExportArchiveHandleOpen(s.WebhookID),
+		t, s.Engine.ExportArchiveHandleOpen(targetID),
 		"a stop that timed out must not close archive writers",
 	)
 }