Add repo-sync-releases admin command (#3254)

* Add repo-sync-releases admin command

Will help recovering corrupted database, see #3247

* Load repos in chunks of 10, exit with error if unable to get a list, scan private repos, fix typo

* Fix debug output about num releases

* Introduce RepositoryListDefaultPageSize constant, set to 64

Use it from the new admin command

* Use RepositoryListDefaultPageSize in more places

* Document RepositoryListDefaultPageSize

models/issue_indexer.go

@@ -29,7 +29,7 @@ func populateIssueIndexer() error {
 	for page := 1; ; page++ {
 		repos, _, err := SearchRepositoryByName(&SearchRepoOptions{
 			Page:        page,
-			PageSize:    10,
+			PageSize:    RepositoryListDefaultPageSize,
 			OrderBy:     SearchOrderByID,
 			Private:     true,
 			Collaborate: util.OptionalBoolFalse,

models/migrations/v39.go

@@ -31,7 +31,7 @@ func releaseAddColumnIsTagAndSyncTags(x *xorm.Engine) error {
 
 	// For the sake of SQLite3, we can't use x.Iterate here.
 	offset := 0
-	pageSize := 20
+	pageSize := models.RepositoryListDefaultPageSize
 	for {
 		repos := make([]*models.Repository, 0, pageSize)
 		if err := x.Table("repository").Asc("id").Limit(pageSize, offset).Find(&repos); err != nil {

models/repo_indexer.go

@@ -81,7 +81,7 @@ func populateRepoIndexer() error {
 	for page := 1; ; page++ {
 		repos, _, err := SearchRepositoryByName(&SearchRepoOptions{
 			Page:     page,
-			PageSize: 10,
+			PageSize: RepositoryListDefaultPageSize,
 			OrderBy:  SearchOrderByID,
 			Private:  true,
 		})

models/repo_list.go

@@ -13,6 +13,13 @@ import (
 	"github.com/go-xorm/builder"
 )
 
+// RepositoryListDefaultPageSize is the default number of repositories
+// to load in memory when running administrative tasks on all (or almost
+// all) of them.
+// The number should be low enough to avoid filling up all RAM with
+// repository data...
+const RepositoryListDefaultPageSize = 64
+
 // RepositoryList contains a list of repositories
 type RepositoryList []*Repository