Remove GetByBean method because sometimes it's danger when query condition parameter is zero and also introduce new generic methods (go-gitea#28220)

The function `GetByBean` has an obvious defect that when the fields are
empty values, it will be ignored. Then users will get a wrong result
which is possibly used to make a security problem.

To avoid the possibility, this PR removed function `GetByBean` and all
references.
And some new generic functions have been introduced to be used.

The recommand usage like below.

```go
// if query an object according id
obj, err := db.GetByID[Object](ctx, id)
// query with other conditions
obj, err := db.Get[Object](ctx, builder.Eq{"a": a, "b":b})
```

Author: lunny

models/asymkey/ssh_key_deploy.go

@@ -131,24 +131,22 @@ func AddDeployKey(ctx context.Context, repoID int64, name, content string, readO
 	}
 	defer committer.Close()
 
-	pkey := &PublicKey{
-		Fingerprint: fingerprint,
-	}
-	has, err := db.GetByBean(ctx, pkey)
+	pkey, exist, err := db.Get[PublicKey](ctx, builder.Eq{"fingerprint": fingerprint})
 	if err != nil {
 		return nil, err
-	}
-
-	if has {
+	} else if exist {
 		if pkey.Type != KeyTypeDeploy {
 			return nil, ErrKeyAlreadyExist{0, fingerprint, ""}
 		}
 	} else {
 		// First time use this deploy key.
-		pkey.Mode = accessMode
-		pkey.Type = KeyTypeDeploy
-		pkey.Content = content
-		pkey.Name = name
+		pkey = &PublicKey{
+			Fingerprint: fingerprint,
+			Mode:        accessMode,
+			Type:        KeyTypeDeploy,
+			Content:     content,
+			Name:        name,
+		}
 		if err = addKey(ctx, pkey); err != nil {
 			return nil, fmt.Errorf("addKey: %w", err)
 		}
@@ -164,26 +162,21 @@ func AddDeployKey(ctx context.Context, repoID int64, name, content string, readO
 
 // GetDeployKeyByID returns deploy key by given ID.
 func GetDeployKeyByID(ctx context.Context, id int64) (*DeployKey, error) {
-	key := new(DeployKey)
-	has, err := db.GetEngine(ctx).ID(id).Get(key)
+	key, exist, err := db.GetByID[DeployKey](ctx, id)
 	if err != nil {
 		return nil, err
-	} else if !has {
+	} else if !exist {
 		return nil, ErrDeployKeyNotExist{id, 0, 0}
 	}
 	return key, nil
 }
 
 // GetDeployKeyByRepo returns deploy key by given public key ID and repository ID.
 func GetDeployKeyByRepo(ctx context.Context, keyID, repoID int64) (*DeployKey, error) {
-	key := &DeployKey{
-		KeyID:  keyID,
-		RepoID: repoID,
-	}
-	has, err := db.GetByBean(ctx, key)
+	key, exist, err := db.Get[DeployKey](ctx, builder.Eq{"key_id": keyID, "repo_id": repoID})
 	if err != nil {
 		return nil, err
-	} else if !has {
+	} else if !exist {
 		return nil, ErrDeployKeyNotExist{0, keyID, repoID}
 	}
 	return key, nil

models/asymkey/ssh_key_fingerprint.go

@@ -15,6 +15,7 @@ import (
 	"code.gitea.io/gitea/modules/util"
 
 	"golang.org/x/crypto/ssh"
+	"xorm.io/builder"
 )
 
 // ___________.__                                         .__        __
@@ -31,9 +32,7 @@ import (
 // checkKeyFingerprint only checks if key fingerprint has been used as public key,
 // it is OK to use same key as deploy key for multiple repositories/users.
 func checkKeyFingerprint(ctx context.Context, fingerprint string) error {
-	has, err := db.GetByBean(ctx, &PublicKey{
-		Fingerprint: fingerprint,
-	})
+	has, err := db.Exist[PublicKey](ctx, builder.Eq{"fingerprint": fingerprint})
 	if err != nil {
 		return err
 	} else if has {

models/auth/session.go

@@ -9,6 +9,8 @@ import (
 
 	"code.gitea.io/gitea/models/db"
 	"code.gitea.io/gitea/modules/timeutil"
+
+	"xorm.io/builder"
 )
 
 // Session represents a session compatible for go-chi session
@@ -33,34 +35,28 @@ func UpdateSession(ctx context.Context, key string, data []byte) error {
 
 // ReadSession reads the data for the provided session
 func ReadSession(ctx context.Context, key string) (*Session, error) {
-	session := Session{
-		Key: key,
-	}
-
 	ctx, committer, err := db.TxContext(ctx)
 	if err != nil {
 		return nil, err
 	}
 	defer committer.Close()
 
-	if has, err := db.GetByBean(ctx, &session); err != nil {
+	session, exist, err := db.Get[Session](ctx, builder.Eq{"key": key})
+	if err != nil {
 		return nil, err
-	} else if !has {
+	} else if !exist {
 		session.Expiry = timeutil.TimeStampNow()
 		if err := db.Insert(ctx, &session); err != nil {
 			return nil, err
 		}
 	}
 
-	return &session, committer.Commit()
+	return session, committer.Commit()
 }
 
 // ExistSession checks if a session exists
 func ExistSession(ctx context.Context, key string) (bool, error) {
-	session := Session{
-		Key: key,
-	}
-	return db.GetEngine(ctx).Get(&session)
+	return db.Exist[Session](ctx, builder.Eq{"key": key})
 }
 
 // DestroySession destroys a session
@@ -79,17 +75,13 @@ func RegenerateSession(ctx context.Context, oldKey, newKey string) (*Session, er
 	}
 	defer committer.Close()
 
-	if has, err := db.GetByBean(ctx, &Session{
-		Key: newKey,
-	}); err != nil {
+	if has, err := db.Exist[Session](ctx, builder.Eq{"key": newKey}); err != nil {
 		return nil, err
 	} else if has {
 		return nil, fmt.Errorf("session Key: %s already exists", newKey)
 	}
 
-	if has, err := db.GetByBean(ctx, &Session{
-		Key: oldKey,
-	}); err != nil {
+	if has, err := db.Exist[Session](ctx, builder.Eq{"key": oldKey}); err != nil {
 		return nil, err
 	} else if !has {
 		if err := db.Insert(ctx, &Session{
@@ -104,14 +96,13 @@ func RegenerateSession(ctx context.Context, oldKey, newKey string) (*Session, er
 		return nil, err
 	}
 
-	s := Session{
-		Key: newKey,
-	}
-	if _, err := db.GetByBean(ctx, &s); err != nil {
+	s, _, err := db.Get[Session](ctx, builder.Eq{"key": newKey})
+	if err != nil {
+		// is not exist, it should be impossible
 		return nil, err
 	}
 
-	return &s, committer.Commit()
+	return s, committer.Commit()
 }
 
 // CountSessions returns the number of sessions

models/auth/source.go

@@ -265,10 +265,10 @@ func IsSSPIEnabled(ctx context.Context) bool {
 		return false
 	}
 
-	exist, err := db.Exists[Source](ctx, FindSourcesOptions{
+	exist, err := db.Exist[Source](ctx, FindSourcesOptions{
 		IsActive:  util.OptionalBoolTrue,
 		LoginType: SSPI,
-	})
+	}.ToConds())
 	if err != nil {
 		log.Error("Active SSPI Sources: %v", err)
 		return false

models/db/context.go

@@ -173,9 +173,44 @@ func Exec(ctx context.Context, sqlAndArgs ...any) (sql.Result, error) {
 	return GetEngine(ctx).Exec(sqlAndArgs...)
 }
 
-// GetByBean filled empty fields of the bean according non-empty fields to query in database.
-func GetByBean(ctx context.Context, bean any) (bool, error) {
-	return GetEngine(ctx).Get(bean)
+func Get[T any](ctx context.Context, cond builder.Cond) (object *T, exist bool, err error) {
+	if !cond.IsValid() {
+		return nil, false, ErrConditionRequired{}
+	}
+
+	var bean T
+	has, err := GetEngine(ctx).Where(cond).NoAutoCondition().Get(&bean)
+	if err != nil {
+		return nil, false, err
+	} else if !has {
+		return nil, false, nil
+	}
+	return &bean, true, nil
+}
+
+func GetByID[T any](ctx context.Context, id int64) (object *T, exist bool, err error) {
+	var bean T
+	has, err := GetEngine(ctx).ID(id).NoAutoCondition().Get(&bean)
+	if err != nil {
+		return nil, false, err
+	} else if !has {
+		return nil, false, nil
+	}
+	return &bean, true, nil
+}
+
+func Exist[T any](ctx context.Context, cond builder.Cond) (bool, error) {
+	if !cond.IsValid() {
+		return false, ErrConditionRequired{}
+	}
+
+	var bean T
+	return GetEngine(ctx).Where(cond).NoAutoCondition().Exist(&bean)
+}
+
+func ExistByID[T any](ctx context.Context, id int64) (bool, error) {
+	var bean T
+	return GetEngine(ctx).ID(id).NoAutoCondition().Exist(&bean)
 }
 
 // DeleteByBean deletes all records according non-empty fields of the bean as conditions.
@@ -264,8 +299,3 @@ func inTransaction(ctx context.Context) (*xorm.Session, bool) {
 		return nil, false
 	}
 }
-
-func Exists[T any](ctx context.Context, opts FindOptions) (bool, error) {
-	var bean T
-	return GetEngine(ctx).Where(opts.ToConds()).Exist(&bean)
-}

models/db/error.go

@@ -72,3 +72,21 @@ func (err ErrNotExist) Error() string {
 func (err ErrNotExist) Unwrap() error {
 	return util.ErrNotExist
 }
+
+// ErrConditionRequired represents an error which require condition.
+type ErrConditionRequired struct{}
+
+// IsErrConditionRequired checks if an error is an ErrConditionRequired
+func IsErrConditionRequired(err error) bool {
+	_, ok := err.(ErrConditionRequired)
+	return ok
+}
+
+func (err ErrConditionRequired) Error() string {
+	return "condition is required"
+}
+
+// Unwrap unwraps this as a ErrNotExist err
+func (err ErrConditionRequired) Unwrap() error {
+	return util.ErrInvalidArgument
+}

models/db/iterate_test.go

@@ -31,11 +31,11 @@ func TestIterate(t *testing.T) {
 	assert.EqualValues(t, cnt, repoUnitCnt)
 
 	err = db.Iterate(db.DefaultContext, nil, func(ctx context.Context, repoUnit *repo_model.RepoUnit) error {
-		reopUnit2 := repo_model.RepoUnit{ID: repoUnit.ID}
-		has, err := db.GetByBean(ctx, &reopUnit2)
+		has, err := db.ExistByID[repo_model.RepoUnit](ctx, repoUnit.ID)
 		if err != nil {
 			return err
-		} else if !has {
+		}
+		if !has {
 			return db.ErrNotExist{Resource: "repo_unit", ID: repoUnit.ID}
 		}
 		assert.EqualValues(t, repoUnit.RepoID, repoUnit.RepoID)

models/git/lfs.go

@@ -135,7 +135,7 @@ var ErrLFSObjectNotExist = db.ErrNotExist{Resource: "LFS Meta object"}
 
 // NewLFSMetaObject stores a given populated LFSMetaObject structure in the database
 // if it is not already present.
-func NewLFSMetaObject(ctx context.Context, m *LFSMetaObject) (*LFSMetaObject, error) {
+func NewLFSMetaObject(ctx context.Context, repoID int64, p lfs.Pointer) (*LFSMetaObject, error) {
 	var err error
 
 	ctx, committer, err := db.TxContext(ctx)
@@ -144,16 +144,15 @@ func NewLFSMetaObject(ctx context.Context, m *LFSMetaObject) (*LFSMetaObject, er
 	}
 	defer committer.Close()
 
-	has, err := db.GetByBean(ctx, m)
+	m, exist, err := db.Get[LFSMetaObject](ctx, builder.Eq{"repository_id": repoID, "oid": p.Oid})
 	if err != nil {
 		return nil, err
-	}
-
-	if has {
+	} else if exist {
 		m.Existing = true
 		return m, committer.Commit()
 	}
 
+	m = &LFSMetaObject{Pointer: p, RepositoryID: repoID}
 	if err = db.Insert(ctx, m); err != nil {
 		return nil, err
 	}

models/git/protected_branch.go

@@ -24,6 +24,7 @@ import (
 
 	"github.com/gobwas/glob"
 	"github.com/gobwas/glob/syntax"
+	"xorm.io/builder"
 )
 
 var ErrBranchIsProtected = errors.New("branch is protected")
@@ -274,25 +275,22 @@ func (protectBranch *ProtectedBranch) IsUnprotectedFile(patterns []glob.Glob, pa
 
 // GetProtectedBranchRuleByName getting protected branch rule by name
 func GetProtectedBranchRuleByName(ctx context.Context, repoID int64, ruleName string) (*ProtectedBranch, error) {
-	rel := &ProtectedBranch{RepoID: repoID, RuleName: ruleName}
-	has, err := db.GetByBean(ctx, rel)
+	// branch_name is legacy name, it actually is rule name
+	rel, exist, err := db.Get[ProtectedBranch](ctx, builder.Eq{"repo_id": repoID, "branch_name": ruleName})
 	if err != nil {
 		return nil, err
-	}
-	if !has {
+	} else if !exist {
 		return nil, nil
 	}
 	return rel, nil
 }
 
 // GetProtectedBranchRuleByID getting protected branch rule by rule ID
 func GetProtectedBranchRuleByID(ctx context.Context, repoID, ruleID int64) (*ProtectedBranch, error) {
-	rel := &ProtectedBranch{ID: ruleID, RepoID: repoID}
-	has, err := db.GetByBean(ctx, rel)
+	rel, exist, err := db.Get[ProtectedBranch](ctx, builder.Eq{"repo_id": repoID, "id": ruleID})
 	if err != nil {
 		return nil, err
-	}
-	if !has {
+	} else if !exist {
 		return nil, nil
 	}
 	return rel, nil

models/issues/assignees.go

@@ -10,6 +10,8 @@ import (
 	"code.gitea.io/gitea/models/db"
 	user_model "code.gitea.io/gitea/models/user"
 	"code.gitea.io/gitea/modules/util"
+
+	"xorm.io/builder"
 )
 
 // IssueAssignees saves all issue assignees
@@ -59,7 +61,7 @@ func GetAssigneeIDsByIssue(ctx context.Context, issueID int64) ([]int64, error)
 
 // IsUserAssignedToIssue returns true when the user is assigned to the issue
 func IsUserAssignedToIssue(ctx context.Context, issue *Issue, user *user_model.User) (isAssigned bool, err error) {
-	return db.GetByBean(ctx, &IssueAssignees{IssueID: issue.ID, AssigneeID: user.ID})
+	return db.Exist[IssueAssignees](ctx, builder.Eq{"assignee_id": user.ID, "issue_id": issue.ID})
 }
 
 // ToggleIssueAssignee changes a user between assigned and not assigned for this issue, and make issue comment for it.