diff --git a/models/ssh_key.go b/models/ssh_key.go
index 98fb2dcdbf..53a31f6f8d 100644
--- a/models/ssh_key.go
+++ b/models/ssh_key.go
@@ -33,10 +33,13 @@ const (
 
 var sshOpLocker sync.Mutex
 
+// KeyType specifies the key type
 type KeyType int
 
 const (
+	// KeyTypeUser specifies the user key
 	KeyTypeUser = iota + 1
+	// KeyTypeDeploy specifies the deploy key
 	KeyTypeDeploy
 )
 
@@ -58,28 +61,31 @@ type PublicKey struct {
 	HasUsed           bool `xorm:"-"`
 }
 
-func (k *PublicKey) BeforeInsert() {
-	k.CreatedUnix = time.Now().Unix()
+// BeforeInsert will be invoked by XORM before inserting a record
+func (key *PublicKey) BeforeInsert() {
+	key.CreatedUnix = time.Now().Unix()
 }
 
-func (k *PublicKey) BeforeUpdate() {
-	k.UpdatedUnix = time.Now().Unix()
+// BeforeUpdate is invoked from XORM before updating this object.
+func (key *PublicKey) BeforeUpdate() {
+	key.UpdatedUnix = time.Now().Unix()
 }
 
-func (k *PublicKey) AfterSet(colName string, _ xorm.Cell) {
+// AfterSet is invoked from XORM after setting the value of a field of this object.
+func (key *PublicKey) AfterSet(colName string, _ xorm.Cell) {
 	switch colName {
 	case "created_unix":
-		k.Created = time.Unix(k.CreatedUnix, 0).Local()
+		key.Created = time.Unix(key.CreatedUnix, 0).Local()
 	case "updated_unix":
-		k.Updated = time.Unix(k.UpdatedUnix, 0).Local()
-		k.HasUsed = k.Updated.After(k.Created)
-		k.HasRecentActivity = k.Updated.Add(7 * 24 * time.Hour).After(time.Now())
+		key.Updated = time.Unix(key.UpdatedUnix, 0).Local()
+		key.HasUsed = key.Updated.After(key.Created)
+		key.HasRecentActivity = key.Updated.Add(7 * 24 * time.Hour).After(time.Now())
 	}
 }
 
 // OmitEmail returns content of public key without email address.
-func (k *PublicKey) OmitEmail() string {
-	return strings.Join(strings.Split(k.Content, " ")[:2], " ")
+func (key *PublicKey) OmitEmail() string {
+	return strings.Join(strings.Split(key.Content, " ")[:2], " ")
 }
 
 // AuthorizedString returns formatted public key string for authorized_keys file.
@@ -573,32 +579,35 @@ type DeployKey struct {
 	HasUsed           bool `xorm:"-"`
 }
 
-func (k *DeployKey) BeforeInsert() {
-	k.CreatedUnix = time.Now().Unix()
+// BeforeInsert will be invoked by XORM before inserting a record
+func (key *DeployKey) BeforeInsert() {
+	key.CreatedUnix = time.Now().Unix()
 }
 
-func (k *DeployKey) BeforeUpdate() {
-	k.UpdatedUnix = time.Now().Unix()
+// BeforeUpdate is invoked from XORM before updating this object.
+func (key *DeployKey) BeforeUpdate() {
+	key.UpdatedUnix = time.Now().Unix()
 }
 
-func (k *DeployKey) AfterSet(colName string, _ xorm.Cell) {
+// AfterSet is invoked from XORM after setting the value of a field of this object.
+func (key *DeployKey) AfterSet(colName string, _ xorm.Cell) {
 	switch colName {
 	case "created_unix":
-		k.Created = time.Unix(k.CreatedUnix, 0).Local()
+		key.Created = time.Unix(key.CreatedUnix, 0).Local()
 	case "updated_unix":
-		k.Updated = time.Unix(k.UpdatedUnix, 0).Local()
-		k.HasUsed = k.Updated.After(k.Created)
-		k.HasRecentActivity = k.Updated.Add(7 * 24 * time.Hour).After(time.Now())
+		key.Updated = time.Unix(key.UpdatedUnix, 0).Local()
+		key.HasUsed = key.Updated.After(key.Created)
+		key.HasRecentActivity = key.Updated.Add(7 * 24 * time.Hour).After(time.Now())
 	}
 }
 
 // GetContent gets associated public key content.
-func (k *DeployKey) GetContent() error {
-	pkey, err := GetPublicKeyByID(k.KeyID)
+func (key *DeployKey) GetContent() error {
+	pkey, err := GetPublicKeyByID(key.KeyID)
 	if err != nil {
 		return err
 	}
-	k.Content = pkey.Content
+	key.Content = pkey.Content
 	return nil
 }