chore: Deglobalize oneclickexporter instance (#64066)

This PR removes the requirement that a global variable is initialized in
the frontend main function. Instead, we create a data exporter where
it's used.

Test plan: CI passes, code review.

cmd/frontend/internal/app/one_click_export.go

@@ -30,7 +30,7 @@ func oneClickExportHandler(db database.DB, logger log.Logger) http.HandlerFunc {
 			return
 		}
 
-		archive, err := oce.GlobalExporter.Export(ctx, request)
+		archive, err := oce.NewDataExporter(db, logger).Export(ctx, request)
 		if err != nil {
 			logger.Error("OneClickExport", log.Error(err))
 			w.WriteHeader(http.StatusInternalServerError)

cmd/frontend/internal/app/one_click_export_test.go

@@ -10,6 +10,7 @@ import (
 	"testing"
 
 	"github.com/sourcegraph/log/logtest"
+
 	oce "github.com/sourcegraph/sourcegraph/cmd/frontend/oneclickexport"
 
 	"github.com/sourcegraph/sourcegraph/internal/actor"
@@ -32,11 +33,6 @@ func TestOneClickExportHandler(t *testing.T) {
 	})
 
 	t.Run("admins can download the archive", func(t *testing.T) {
-		oce.GlobalExporter = oce.NewDataExporter(db, logger)
-		t.Cleanup(func() {
-			oce.GlobalExporter = nil
-		})
-
 		request := oce.ExportRequest{
 			IncludeSiteConfig:     true,
 			IncludeCodeHostConfig: true,

cmd/frontend/internal/cli/BUILD.bazel

@@ -33,7 +33,6 @@ go_library(
         "//cmd/frontend/internal/cli/middleware",
         "//cmd/frontend/internal/highlight",
         "//cmd/frontend/internal/httpapi",
-        "//cmd/frontend/oneclickexport",
         "//internal/actor",
         "//internal/api",
         "//internal/auth",

cmd/frontend/internal/cli/serve_cmd.go

@@ -26,7 +26,6 @@ import (
 	"github.com/sourcegraph/sourcegraph/cmd/frontend/internal/bg"
 	"github.com/sourcegraph/sourcegraph/cmd/frontend/internal/highlight"
 	"github.com/sourcegraph/sourcegraph/cmd/frontend/internal/httpapi"
-	oce "github.com/sourcegraph/sourcegraph/cmd/frontend/oneclickexport"
 	"github.com/sourcegraph/sourcegraph/internal/api"
 	"github.com/sourcegraph/sourcegraph/internal/authz/providers"
 	"github.com/sourcegraph/sourcegraph/internal/conf"
@@ -244,8 +243,6 @@ func Main(ctx context.Context, observationCtx *observation.Context, ready servic
 		routines = append(routines, internalAPI)
 	}
 
-	oce.GlobalExporter = oce.NewDataExporter(db, logger)
-
 	debugserverEndpoints.GlobalRateLimiterState = http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
 		info, err := ratelimit.GetGlobalLimiterState(r.Context())
 		if err != nil {

cmd/frontend/oneclickexport/export.go

@@ -9,6 +9,7 @@ import (
 	"path/filepath"
 
 	"github.com/sourcegraph/log"
+
 	"github.com/sourcegraph/sourcegraph/internal/database"
 )
 
@@ -20,8 +21,6 @@ type Exporter interface {
 
 var _ Exporter = &DataExporter{}
 
-var GlobalExporter Exporter
-
 type DataExporter struct {
 	logger           log.Logger
 	configProcessors map[string]Processor[ConfigRequest]