Simplify how git repositories are opened (#28937)

## Purpose
This is a refactor toward building an abstraction over managing git
repositories.
Afterwards, it does not matter anymore if they are stored on the local
disk or somewhere remote.

## What this PR changes
We used `git.OpenRepository` everywhere previously.
Now, we should split them into two distinct functions:

Firstly, there are temporary repositories which do not change:

```go
git.OpenRepository(ctx, diskPath)
```

Gitea managed repositories having a record in the database in the
`repository` table are moved into the new package `gitrepo`:

```go
gitrepo.OpenRepository(ctx, repo_model.Repo)
```

Why is `repo_model.Repository` the second parameter instead of file
path?
Because then we can easily adapt our repository storage strategy.
The repositories can be stored locally, however, they could just as well
be stored on a remote server.

## Further changes in other PRs
- A Git Command wrapper on package `gitrepo` could be created. i.e.
`NewCommand(ctx, repo_model.Repository, commands...)`. `git.RunOpts{Dir:
repo.RepoPath()}`, the directory should be empty before invoking this
method and it can be filled in the function only. #28940
- Remove the `RepoPath()`/`WikiPath()` functions to reduce the
possibility of mistakes.

---------

Co-authored-by: delvh <dev.lh@web.de>

6 files changed, 22 insertions, 16 deletions

diff --git a/routers/web/repo/commit.go b/routers/web/repo/commit.go
index 00157d44c9..32fa973ef6 100644
--- a/routers/web/repo/commit.go
+++ b/routers/web/repo/commit.go
@@ -22,6 +22,7 @@ import (
 	"code.gitea.io/gitea/modules/context"
 	"code.gitea.io/gitea/modules/git"
 	"code.gitea.io/gitea/modules/gitgraph"
+	"code.gitea.io/gitea/modules/gitrepo"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/markup"
 	"code.gitea.io/gitea/modules/setting"
@@ -279,7 +280,7 @@ func Diff(ctx *context.Context) {
 	)
 
 	if ctx.Data["PageIsWiki"] != nil {
-		gitRepo, err = git.OpenRepository(ctx, ctx.Repo.Repository.WikiPath())
+		gitRepo, err = gitrepo.OpenWikiRepository(ctx, ctx.Repo.Repository)
 		if err != nil {
 			ctx.ServerError("Repo.GitRepo.GetCommit", err)
 			return
@@ -404,7 +405,7 @@ func Diff(ctx *context.Context) {
 func RawDiff(ctx *context.Context) {
 	var gitRepo *git.Repository
 	if ctx.Data["PageIsWiki"] != nil {
-		wikiRepo, err := git.OpenRepository(ctx, ctx.Repo.Repository.WikiPath())
+		wikiRepo, err := gitrepo.OpenWikiRepository(ctx, ctx.Repo.Repository)
 		if err != nil {
 			ctx.ServerError("OpenRepository", err)
 			return
diff --git a/routers/web/repo/compare.go b/routers/web/repo/compare.go
index 5ae48e1ce8..a3593815b8 100644
--- a/routers/web/repo/compare.go
+++ b/routers/web/repo/compare.go
@@ -28,6 +28,7 @@ import (
 	"code.gitea.io/gitea/modules/context"
 	csv_module "code.gitea.io/gitea/modules/csv"
 	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/gitrepo"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/markup"
 	"code.gitea.io/gitea/modules/setting"
@@ -408,7 +409,7 @@ func ParseCompareInfo(ctx *context.Context) *CompareInfo {
 		ci.HeadRepo = ctx.Repo.Repository
 		ci.HeadGitRepo = ctx.Repo.GitRepo
 	} else if has {
-		ci.HeadGitRepo, err = git.OpenRepository(ctx, ci.HeadRepo.RepoPath())
+		ci.HeadGitRepo, err = gitrepo.OpenRepository(ctx, ci.HeadRepo)
 		if err != nil {
 			ctx.ServerError("OpenRepository", err)
 			return nil
@@ -688,7 +689,7 @@ func PrepareCompareDiff(
 }
 
 func getBranchesAndTagsForRepo(ctx gocontext.Context, repo *repo_model.Repository) (branches, tags []string, err error) {
-	gitRepo, err := git.OpenRepository(ctx, repo.RepoPath())
+	gitRepo, err := gitrepo.OpenRepository(ctx, repo)
 	if err != nil {
 		return nil, nil, err
 	}
@@ -876,7 +877,7 @@ func ExcerptBlob(ctx *context.Context) {
 	gitRepo := ctx.Repo.GitRepo
 	if ctx.FormBool("wiki") {
 		var err error
-		gitRepo, err = git.OpenRepository(ctx, ctx.Repo.Repository.WikiPath())
+		gitRepo, err = gitrepo.OpenWikiRepository(ctx, ctx.Repo.Repository)
 		if err != nil {
 			ctx.ServerError("OpenRepository", err)
 			return
diff --git a/routers/web/repo/editor_test.go b/routers/web/repo/editor_test.go
index 67fb277d5c..c28c3ef1d6 100644
--- a/routers/web/repo/editor_test.go
+++ b/routers/web/repo/editor_test.go
@@ -9,6 +9,7 @@ import (
 	"code.gitea.io/gitea/models/unittest"
 	"code.gitea.io/gitea/modules/contexttest"
 	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/gitrepo"
 
 	"github.com/stretchr/testify/assert"
 )
@@ -66,7 +67,7 @@ func TestGetClosestParentWithFiles(t *testing.T) {
 
 	repo := ctx.Repo.Repository
 	branch := repo.DefaultBranch
-	gitRepo, _ := git.OpenRepository(git.DefaultContext, repo.RepoPath())
+	gitRepo, _ := gitrepo.OpenRepository(git.DefaultContext, repo)
 	defer gitRepo.Close()
 	commit, _ := gitRepo.GetBranchCommit(branch)
 	var expectedTreePath string // Should return the root dir, empty string, since there are no subdirs in this repo
diff --git a/routers/web/repo/pull.go b/routers/web/repo/pull.go
index e36d7092af..b265cf4754 100644
--- a/routers/web/repo/pull.go
+++ b/routers/web/repo/pull.go
@@ -29,6 +29,7 @@ import (
 	"code.gitea.io/gitea/modules/base"
 	"code.gitea.io/gitea/modules/context"
 	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/gitrepo"
 	issue_template "code.gitea.io/gitea/modules/issue/template"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/setting"
@@ -530,7 +531,7 @@ func PrepareViewPullInfo(ctx *context.Context, issue *issues_model.Issue) *git.C
 	if pull.BaseRepoID == ctx.Repo.Repository.ID && ctx.Repo.GitRepo != nil {
 		baseGitRepo = ctx.Repo.GitRepo
 	} else {
-		baseGitRepo, err := git.OpenRepository(ctx, pull.BaseRepo.RepoPath())
+		baseGitRepo, err := gitrepo.OpenRepository(ctx, pull.BaseRepo)
 		if err != nil {
 			ctx.ServerError("OpenRepository", err)
 			return nil
@@ -582,7 +583,7 @@ func PrepareViewPullInfo(ctx *context.Context, issue *issues_model.Issue) *git.C
 	var headBranchSha string
 	// HeadRepo may be missing
 	if pull.HeadRepo != nil {
-		headGitRepo, err := git.OpenRepository(ctx, pull.HeadRepo.RepoPath())
+		headGitRepo, err := gitrepo.OpenRepository(ctx, pull.HeadRepo)
 		if err != nil {
 			ctx.ServerError("OpenRepository", err)
 			return nil
@@ -1314,9 +1315,9 @@ func MergePullRequest(ctx *context.Context) {
 		if ctx.Repo != nil && ctx.Repo.Repository != nil && pr.HeadRepoID == ctx.Repo.Repository.ID && ctx.Repo.GitRepo != nil {
 			headRepo = ctx.Repo.GitRepo
 		} else {
-			headRepo, err = git.OpenRepository(ctx, pr.HeadRepo.RepoPath())
+			headRepo, err = gitrepo.OpenRepository(ctx, pr.HeadRepo)
 			if err != nil {
-				ctx.ServerError(fmt.Sprintf("OpenRepository[%s]", pr.HeadRepo.RepoPath()), err)
+				ctx.ServerError(fmt.Sprintf("OpenRepository[%s]", pr.HeadRepo.FullName()), err)
 				return
 			}
 			defer headRepo.Close()
@@ -1537,9 +1538,9 @@ func CleanUpPullRequest(ctx *context.Context) {
 		gitBaseRepo = ctx.Repo.GitRepo
 	} else {
 		// If not just open it
-		gitBaseRepo, err = git.OpenRepository(ctx, pr.BaseRepo.RepoPath())
+		gitBaseRepo, err = gitrepo.OpenRepository(ctx, pr.BaseRepo)
 		if err != nil {
-			ctx.ServerError(fmt.Sprintf("OpenRepository[%s]", pr.BaseRepo.RepoPath()), err)
+			ctx.ServerError(fmt.Sprintf("OpenRepository[%s]", pr.BaseRepo.FullName()), err)
 			return
 		}
 		defer gitBaseRepo.Close()
@@ -1552,9 +1553,9 @@ func CleanUpPullRequest(ctx *context.Context) {
 		gitRepo = ctx.Repo.GitRepo
 	} else if pr.BaseRepoID != pr.HeadRepoID {
 		// Otherwise just load it up
-		gitRepo, err = git.OpenRepository(ctx, pr.HeadRepo.RepoPath())
+		gitRepo, err = gitrepo.OpenRepository(ctx, pr.HeadRepo)
 		if err != nil {
-			ctx.ServerError(fmt.Sprintf("OpenRepository[%s]", pr.HeadRepo.RepoPath()), err)
+			ctx.ServerError(fmt.Sprintf("OpenRepository[%s]", pr.HeadRepo.FullName()), err)
 			return
 		}
 		defer gitRepo.Close()
diff --git a/routers/web/repo/wiki.go b/routers/web/repo/wiki.go
index 4e09f046cf..5e7b971e67 100644
--- a/routers/web/repo/wiki.go
+++ b/routers/web/repo/wiki.go
@@ -20,6 +20,7 @@ import (
 	"code.gitea.io/gitea/modules/charset"
 	"code.gitea.io/gitea/modules/context"
 	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/gitrepo"
 	"code.gitea.io/gitea/modules/log"
 	"code.gitea.io/gitea/modules/markup"
 	"code.gitea.io/gitea/modules/markup/markdown"
@@ -92,7 +93,7 @@ func findEntryForFile(commit *git.Commit, target string) (*git.TreeEntry, error)
 }
 
 func findWikiRepoCommit(ctx *context.Context) (*git.Repository, *git.Commit, error) {
-	wikiRepo, err := git.OpenRepository(ctx, ctx.Repo.Repository.WikiPath())
+	wikiRepo, err := gitrepo.OpenWikiRepository(ctx, ctx.Repo.Repository)
 	if err != nil {
 		ctx.ServerError("OpenRepository", err)
 		return nil, nil, err
diff --git a/routers/web/repo/wiki_test.go b/routers/web/repo/wiki_test.go
index ae050df967..d3decdae2d 100644
--- a/routers/web/repo/wiki_test.go
+++ b/routers/web/repo/wiki_test.go
@@ -13,6 +13,7 @@ import (
 	"code.gitea.io/gitea/models/unittest"
 	"code.gitea.io/gitea/modules/contexttest"
 	"code.gitea.io/gitea/modules/git"
+	"code.gitea.io/gitea/modules/gitrepo"
 	"code.gitea.io/gitea/modules/web"
 	"code.gitea.io/gitea/services/forms"
 	wiki_service "code.gitea.io/gitea/services/wiki"
@@ -26,7 +27,7 @@ const (
 )
 
 func wikiEntry(t *testing.T, repo *repo_model.Repository, wikiName wiki_service.WebPath) *git.TreeEntry {
-	wikiRepo, err := git.OpenRepository(git.DefaultContext, repo.WikiPath())
+	wikiRepo, err := gitrepo.OpenWikiRepository(git.DefaultContext, repo)
 	assert.NoError(t, err)
 	defer wikiRepo.Close()
 	commit, err := wikiRepo.GetBranchCommit("master")