Fix a bug where lfs gc never worked. (#35198) (#35255)

Backport #35198 by @lunny

Fix #31113

After #22385 introduced LFS GC, it never worked due to a bug in the INI
library: fields in structs embedded more than one level deep are not
populated from the INI file.

This PR fixes the issue by replacing the multi-level embedded struct
with a single-level struct for parsing the cron.gc_lfs configuration.

Added a new test for retrieving cron settings to demonstrate the bug in
the INI package.

Co-authored-by: Lunny Xiao <xiaolunwen@gmail.com>

modules/setting/cron_test.go

@@ -41,3 +41,56 @@ EXTEND = true
 	assert.Equal(t, "white rabbit", extended.Second)
 	assert.True(t, extended.Extend)
 }
+
+// Test_getCronSettings2 tests that getCronSettings can not handle two levels of embedding
+func Test_getCronSettings2(t *testing.T) {
+	type BaseStruct struct {
+		Enabled    bool
+		RunAtStart bool
+		Schedule   string
+	}
+
+	type Extended struct {
+		BaseStruct
+		Extend bool
+	}
+	type Extended2 struct {
+		Extended
+		Third string
+	}
+
+	iniStr := `
+[cron.test]
+ENABLED = TRUE
+RUN_AT_START = TRUE
+SCHEDULE = @every 1h
+EXTEND = true
+THIRD = white rabbit
+`
+	cfg, err := NewConfigProviderFromData(iniStr)
+	assert.NoError(t, err)
+
+	extended := &Extended2{
+		Extended: Extended{
+			BaseStruct: BaseStruct{
+				Enabled:    false,
+				RunAtStart: false,
+				Schedule:   "@every 72h",
+			},
+			Extend: false,
+		},
+		Third: "black rabbit",
+	}
+
+	_, err = getCronSettings(cfg, "test", extended)
+	assert.NoError(t, err)
+
+	// This confirms the first level of embedding works
+	assert.Equal(t, "white rabbit", extended.Third)
+	assert.True(t, extended.Extend)
+
+	// This confirms 2 levels of embedding doesn't work
+	assert.False(t, extended.Enabled)
+	assert.False(t, extended.RunAtStart)
+	assert.Equal(t, "@every 72h", extended.Schedule)
+}

services/cron/tasks_extended.go

@@ -171,34 +171,35 @@ func registerDeleteOldSystemNotices() {
 	})
 }
 
+type GCLFSConfig struct {
+	BaseConfig
+	OlderThan                time.Duration
+	LastUpdatedMoreThanAgo   time.Duration
+	NumberToCheckPerRepo     int64
+	ProportionToCheckPerRepo float64
+}
+
 func registerGCLFS() {
 	if !setting.LFS.StartServer {
 		return
 	}
-	type GCLFSConfig struct {
-		OlderThanConfig
-		LastUpdatedMoreThanAgo   time.Duration
-		NumberToCheckPerRepo     int64
-		ProportionToCheckPerRepo float64
-	}
 
 	RegisterTaskFatal("gc_lfs", &GCLFSConfig{
-		OlderThanConfig: OlderThanConfig{
-			BaseConfig: BaseConfig{
-				Enabled:    false,
-				RunAtStart: false,
-				Schedule:   "@every 24h",
-			},
-			// Only attempt to garbage collect lfs meta objects older than a week as the order of git lfs upload
-			// and git object upload is not necessarily guaranteed. It's possible to imagine a situation whereby
-			// an LFS object is uploaded but the git branch is not uploaded immediately, or there are some rapid
-			// changes in new branches that might lead to lfs objects becoming temporarily unassociated with git
-			// objects.
-			//
-			// It is likely that a week is potentially excessive but it should definitely be enough that any
-			// unassociated LFS object is genuinely unassociated.
-			OlderThan: 24 * time.Hour * 7,
+		BaseConfig: BaseConfig{
+			Enabled:    false,
+			RunAtStart: false,
+			Schedule:   "@every 24h",
 		},
+		// Only attempt to garbage collect lfs meta objects older than a week as the order of git lfs upload
+		// and git object upload is not necessarily guaranteed. It's possible to imagine a situation whereby
+		// an LFS object is uploaded but the git branch is not uploaded immediately, or there are some rapid
+		// changes in new branches that might lead to lfs objects becoming temporarily unassociated with git
+		// objects.
+		//
+		// It is likely that a week is potentially excessive but it should definitely be enough that any
+		// unassociated LFS object is genuinely unassociated.
+		OlderThan: 24 * time.Hour * 7,
+
 		// Only GC things that haven't been looked at in the past 3 days
 		LastUpdatedMoreThanAgo:   24 * time.Hour * 3,
 		NumberToCheckPerRepo:     100,

services/cron/tasks_extended_test.go

@@ -0,0 +1,51 @@
+// Copyright 2025 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package cron
+
+import (
+	"testing"
+	"time"
+
+	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/test"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func Test_GCLFSConfig(t *testing.T) {
+	cfg, err := setting.NewConfigProviderFromData(`
+[cron.gc_lfs]
+ENABLED = true
+RUN_AT_START = true
+SCHEDULE = "@every 2h"
+OLDER_THAN = "1h"
+LAST_UPDATED_MORE_THAN_AGO = "7h"
+NUMBER_TO_CHECK_PER_REPO = 10
+PROPORTION_TO_CHECK_PER_REPO = 0.1
+`)
+	assert.NoError(t, err)
+	defer test.MockVariableValue(&setting.CfgProvider, cfg)()
+
+	config := &GCLFSConfig{
+		BaseConfig: BaseConfig{
+			Enabled:    false,
+			RunAtStart: false,
+			Schedule:   "@every 24h",
+		},
+		OlderThan:                24 * time.Hour * 7,
+		LastUpdatedMoreThanAgo:   24 * time.Hour * 3,
+		NumberToCheckPerRepo:     100,
+		ProportionToCheckPerRepo: 0.6,
+	}
+
+	_, err = setting.GetCronSettings("gc_lfs", config)
+	assert.NoError(t, err)
+	assert.True(t, config.Enabled)
+	assert.True(t, config.RunAtStart)
+	assert.Equal(t, "@every 2h", config.Schedule)
+	assert.Equal(t, 1*time.Hour, config.OlderThan)
+	assert.Equal(t, 7*time.Hour, config.LastUpdatedMoreThanAgo)
+	assert.Equal(t, int64(10), config.NumberToCheckPerRepo)
+	assert.InDelta(t, 0.1, config.ProportionToCheckPerRepo, 0.001)
+}