storage: Surface "already exists" errors.

storage/sql/config.go

@@ -8,6 +8,13 @@ import (
 
 	"github.com/Sirupsen/logrus"
 	"github.com/coreos/dex/storage"
+	"github.com/lib/pq"
+	sqlite3 "github.com/mattn/go-sqlite3"
+)
+
+const (
+	// postgres error codes
+	pgErrUniqueViolation = "23505" // unique_violation
 )
 
 // SQLite3 options for creating an SQL db.
@@ -35,7 +42,16 @@ func (s *SQLite3) open(logger logrus.FieldLogger) (*conn, error) {
 		// doesn't support this, so limit the number of connections to 1.
 		db.SetMaxOpenConns(1)
 	}
-	c := &conn{db, flavorSQLite3, logger}
+
+	errCheck := func(err error) bool {
+		sqlErr, ok := err.(sqlite3.Error)
+		if !ok {
+			return false
+		}
+		return sqlErr.ExtendedCode == sqlite3.ErrConstraintPrimaryKey
+	}
+
+	c := &conn{db, flavorSQLite3, logger, errCheck}
 	if _, err := c.migrate(); err != nil {
 		return nil, fmt.Errorf("failed to perform migrations: %v", err)
 	}
@@ -114,7 +130,16 @@ func (p *Postgres) open(logger logrus.FieldLogger) (*conn, error) {
 	if err != nil {
 		return nil, err
 	}
-	c := &conn{db, flavorPostgres, logger}
+
+	errCheck := func(err error) bool {
+		sqlErr, ok := err.(*pq.Error)
+		if !ok {
+			return false
+		}
+		return sqlErr.Code == pgErrUniqueViolation
+	}
+
+	c := &conn{db, flavorPostgres, logger, errCheck}
 	if _, err := c.migrate(); err != nil {
 		return nil, fmt.Errorf("failed to perform migrations: %v", err)
 	}

storage/sql/crud.go

@@ -125,6 +125,9 @@ func (c *conn) CreateAuthRequest(a storage.AuthRequest) error {
 		a.Expiry,
 	)
 	if err != nil {
+		if c.alreadyExistsCheck(err) {
+			return storage.ErrAlreadyExists
+		}
 		return fmt.Errorf("insert auth request: %v", err)
 	}
 	return nil
@@ -212,7 +215,14 @@ func (c *conn) CreateAuthCode(a storage.AuthCode) error {
 		a.Claims.Username, a.Claims.Email, a.Claims.EmailVerified, encoder(a.Claims.Groups),
 		a.ConnectorID, a.ConnectorData, a.Expiry,
 	)
-	return err
+
+	if err != nil {
+		if c.alreadyExistsCheck(err) {
+			return storage.ErrAlreadyExists
+		}
+		return fmt.Errorf("insert auth code: %v", err)
+	}
+	return nil
 }
 
 func (c *conn) GetAuthCode(id string) (a storage.AuthCode, err error) {
@@ -256,6 +266,9 @@ func (c *conn) CreateRefresh(r storage.RefreshToken) error {
 		r.Token, r.CreatedAt, r.LastUsed,
 	)
 	if err != nil {
+		if c.alreadyExistsCheck(err) {
+			return storage.ErrAlreadyExists
+		}
 		return fmt.Errorf("insert refresh_token: %v", err)
 	}
 	return nil
@@ -477,6 +490,9 @@ func (c *conn) CreateClient(cli storage.Client) error {
 		cli.Public, cli.Name, cli.LogoURL,
 	)
 	if err != nil {
+		if c.alreadyExistsCheck(err) {
+			return storage.ErrAlreadyExists
+		}
 		return fmt.Errorf("insert client: %v", err)
 	}
 	return nil
@@ -544,6 +560,9 @@ func (c *conn) CreatePassword(p storage.Password) error {
 		p.Email, p.Hash, p.Username, p.UserID,
 	)
 	if err != nil {
+		if c.alreadyExistsCheck(err) {
+			return storage.ErrAlreadyExists
+		}
 		return fmt.Errorf("insert password: %v", err)
 	}
 	return nil
@@ -636,6 +655,9 @@ func (c *conn) CreateOfflineSessions(s storage.OfflineSessions) error {
 		s.UserID, s.ConnID, encoder(s.Refresh),
 	)
 	if err != nil {
+		if c.alreadyExistsCheck(err) {
+			return storage.ErrAlreadyExists
+		}
 		return fmt.Errorf("insert offline session: %v", err)
 	}
 	return nil

storage/sql/migrate_test.go

@@ -6,6 +6,7 @@ import (
 	"testing"
 
 	"github.com/Sirupsen/logrus"
+	sqlite3 "github.com/mattn/go-sqlite3"
 )
 
 func TestMigrate(t *testing.T) {
@@ -21,7 +22,15 @@ func TestMigrate(t *testing.T) {
 		Level:     logrus.DebugLevel,
 	}
 
-	c := &conn{db, flavorSQLite3, logger}
+	errCheck := func(err error) bool {
+		sqlErr, ok := err.(sqlite3.Error)
+		if !ok {
+			return false
+		}
+		return sqlErr.ExtendedCode == sqlite3.ErrConstraintUnique
+	}
+
+	c := &conn{db, flavorSQLite3, logger, errCheck}
 	for _, want := range []int{len(migrations), 0} {
 		got, err := c.migrate()
 		if err != nil {

storage/sql/sql.go

@@ -131,9 +131,10 @@ func (c *conn) translateArgs(args []interface{}) []interface{} {
 
 // conn is the main database connection.
 type conn struct {
-	db     *sql.DB
-	flavor flavor
-	logger logrus.FieldLogger
+	db                 *sql.DB
+	flavor             flavor
+	logger             logrus.FieldLogger
+	alreadyExistsCheck func(err error) bool
 }
 
 func (c *conn) Close() error {