sqlstore: add support for checking if error is constraint validation error

pkg/services/sqlstore/migrator/dialect.go

@@ -44,6 +44,8 @@ type Dialect interface {
 
 	CleanDB() error
 	NoOpSql() string
+
+	IsUniqueConstraintViolation(err error) bool
 }
 
 func NewDialect(engine *xorm.Engine) Dialect {

pkg/services/sqlstore/migrator/mysql_dialect.go

@@ -5,6 +5,8 @@ import (
 	"strconv"
 	"strings"
 
+	"github.com/VividCortex/mysqlerr"
+	"github.com/go-sql-driver/mysql"
 	"github.com/go-xorm/xorm"
 )
 
@@ -125,3 +127,13 @@ func (db *Mysql) CleanDB() error {
 
 	return nil
 }
+
+func (db *Mysql) IsUniqueConstraintViolation(err error) bool {
+	if driverErr, ok := err.(*mysql.MySQLError); ok {
+		if driverErr.Number == mysqlerr.ER_DUP_ENTRY {
+			return true
+		}
+	}
+
+	return false
+}

pkg/services/sqlstore/migrator/postgres_dialect.go

@@ -6,6 +6,7 @@ import (
 	"strings"
 
 	"github.com/go-xorm/xorm"
+	"github.com/lib/pq"
 )
 
 type Postgres struct {
@@ -136,3 +137,13 @@ func (db *Postgres) CleanDB() error {
 
 	return nil
 }
+
+func (db *Postgres) IsUniqueConstraintViolation(err error) bool {
+	if driverErr, ok := err.(*pq.Error); ok {
+		if driverErr.Code == "23505" {
+			return true
+		}
+	}
+
+	return false
+}

pkg/services/sqlstore/migrator/sqlite_dialect.go

@@ -4,6 +4,7 @@ import (
 	"fmt"
 
 	"github.com/go-xorm/xorm"
+	sqlite3 "github.com/mattn/go-sqlite3"
 )
 
 type Sqlite3 struct {
@@ -82,3 +83,13 @@ func (db *Sqlite3) DropIndexSql(tableName string, index *Index) string {
 func (db *Sqlite3) CleanDB() error {
 	return nil
 }
+
+func (db *Sqlite3) IsUniqueConstraintViolation(err error) bool {
+	if driverErr, ok := err.(sqlite3.Error); ok {
+		if driverErr.ExtendedCode == sqlite3.ErrConstraintUnique {
+			return true
+		}
+	}
+
+	return false
+}