[FEAT] Restrict file size of blame operation

- Currently there exists a restriction to not render and show files that
are larger than what's configured in `[UI].MAX_DISPLAY_FILE_SIZE`.
- Apply the same restriction to the blame operation as well, as the
blame operation can be seen as displaying a file.
- Add integration test.
- Ref: #2394

routers/web/repo/blame.go

@@ -16,6 +16,7 @@ import (
 	"code.gitea.io/gitea/modules/git"
 	"code.gitea.io/gitea/modules/highlight"
 	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/templates"
 	"code.gitea.io/gitea/modules/timeutil"
 	"code.gitea.io/gitea/modules/util"
@@ -69,6 +70,14 @@ func RefBlame(ctx *context.Context) {
 	ctx.Data["FileSize"] = blob.Size()
 	ctx.Data["FileName"] = blob.Name()
 
+	// Do not display a blame view if the size of the file is
+	// larger than what is configured as the maximum.
+	if blob.Size() >= setting.UI.MaxDisplayFileSize {
+		ctx.Data["IsFileTooLarge"] = true
+		ctx.HTML(http.StatusOK, tplRepoHome)
+		return
+	}
+
 	ctx.Data["NumLinesSet"] = true
 	ctx.Data["NumLines"], err = blob.GetBlobLineCount()
 	if err != nil {

templates/repo/blame.tmpl

@@ -30,6 +30,15 @@
 	</h4>
 	<div class="ui attached table unstackable segment">
 		<div class="file-view code-view unicode-escaped">
+			{{if .IsFileTooLarge}}
+				<table>
+					<tbody>
+						<tr>
+							<td class="gt-text-center gt-p-1"><strong>{{ctx.Locale.Tr "repo.file_too_large"}}</strong></td>
+						</tr>
+					</tbody>
+				</table>
+			{{else}}
 			<table>
 				<tbody>
 					{{range $row := .BlameRows}}
@@ -75,6 +84,7 @@
 					{{end}}
 				</tbody>
 			</table>
+			{{end}}
 		</div>
 	</div>
 </div>

tests/integration/repo_test.go

@@ -15,13 +15,16 @@ import (
 	repo_model "code.gitea.io/gitea/models/repo"
 	unit_model "code.gitea.io/gitea/models/unit"
 	"code.gitea.io/gitea/models/unittest"
+	"code.gitea.io/gitea/modules/git"
 	"code.gitea.io/gitea/modules/setting"
 	"code.gitea.io/gitea/modules/test"
+	"code.gitea.io/gitea/modules/translation"
 	repo_service "code.gitea.io/gitea/services/repository"
 	"code.gitea.io/gitea/tests"
 
 	"github.com/PuerkitoBio/goquery"
 	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/require"
 )
 
 func TestViewRepo(t *testing.T) {
@@ -447,6 +450,9 @@ func TestBlameFileInRepo(t *testing.T) {
 
 	session := loginUser(t, "user2")
 
+	t.Run("Assert", func(t *testing.T) {
+		defer tests.PrintCurrentTest(t)()
+
 		req := NewRequest(t, "GET", "/user2/repo1/blame/branch/master/README.md")
 		resp := session.MakeRequest(t, req, http.StatusOK)
 
@@ -458,6 +464,47 @@ func TestBlameFileInRepo(t *testing.T) {
 		assert.EqualValues(t, 0, description.Length())
 		assert.EqualValues(t, 0, repoTopics.Length())
 		assert.EqualValues(t, 0, repoSummary.Length())
+	})
+
+	t.Run("File size", func(t *testing.T) {
+		defer tests.PrintCurrentTest(t)()
+
+		repo := unittest.AssertExistsAndLoadBean(t, &repo_model.Repository{ID: 1})
+		gitRepo, err := git.OpenRepository(git.DefaultContext, repo.RepoPath())
+		require.NoError(t, err)
+		defer gitRepo.Close()
+
+		commit, err := gitRepo.GetCommit("HEAD")
+		require.NoError(t, err)
+
+		blob, err := commit.GetBlobByPath("README.md")
+		require.NoError(t, err)
+
+		fileSize := blob.Size()
+		require.NotZero(t, fileSize)
+
+		t.Run("Above maximum", func(t *testing.T) {
+			defer tests.PrintCurrentTest(t)()
+			defer test.MockVariableValue(&setting.UI.MaxDisplayFileSize, fileSize)()
+
+			req := NewRequest(t, "GET", "/user2/repo1/blame/branch/master/README.md")
+			resp := session.MakeRequest(t, req, http.StatusOK)
+
+			htmlDoc := NewHTMLParser(t, resp.Body)
+			assert.Contains(t, htmlDoc.Find(".code-view").Text(), translation.NewLocale("en-US").Tr("repo.file_too_large"))
+		})
+
+		t.Run("Under maximum", func(t *testing.T) {
+			defer tests.PrintCurrentTest(t)()
+			defer test.MockVariableValue(&setting.UI.MaxDisplayFileSize, fileSize+1)()
+
+			req := NewRequest(t, "GET", "/user2/repo1/blame/branch/master/README.md")
+			resp := session.MakeRequest(t, req, http.StatusOK)
+
+			htmlDoc := NewHTMLParser(t, resp.Body)
+			assert.NotContains(t, htmlDoc.Find(".code-view").Text(), translation.NewLocale("en-US").Tr("repo.file_too_large"))
+		})
+	})
 }
 
 // TestViewRepoDirectory repo description, topics and summary should not be displayed when within a directory