feat(connector): add compile-time checks for connector interfaces (#4591)

Signed-off-by: maksim.nabokikh <max.nabokih@gmail.com>

connector/atlassiancrowd/atlassiancrowd.go

@@ -87,16 +87,16 @@ func (c *Config) Open(id string, logger *slog.Logger) (connector.Connector, erro
 	return &crowdConnector{Config: *c, logger: logger.With(slog.Group("connector", "type", "atlassiancrowd", "id", id))}, nil
 }
 
-type crowdConnector struct {
-	Config
-	logger *slog.Logger
-}
-
 var (
 	_ connector.PasswordConnector = (*crowdConnector)(nil)
 	_ connector.RefreshConnector  = (*crowdConnector)(nil)
 )
 
+type crowdConnector struct {
+	Config
+	logger *slog.Logger
+}
+
 type refreshData struct {
 	Username string `json:"username"`
 }

connector/authproxy/authproxy.go

@@ -68,6 +68,8 @@ func (c *Config) Open(id string, logger *slog.Logger) (connector.Connector, erro
 	}, nil
 }
 
+var _ connector.CallbackConnector = (*callback)(nil)
+
 // Callback is a connector which returns an identity with the HTTP header
 // X-Remote-User as verified email.
 type callback struct {

connector/keystone/keystone.go

@@ -15,6 +15,11 @@ import (
 	"github.com/dexidp/dex/connector"
 )
 
+var (
+	_ connector.PasswordConnector = (*conn)(nil)
+	_ connector.RefreshConnector  = (*conn)(nil)
+)
+
 type conn struct {
 	Domain        domainKeystone
 	Host          string
@@ -103,11 +108,6 @@ type userResponse struct {
 	} `json:"user"`
 }
 
-var (
-	_ connector.PasswordConnector = &conn{}
-	_ connector.RefreshConnector  = &conn{}
-)
-
 // Open returns an authentication strategy using Keystone.
 func (c *Config) Open(id string, logger *slog.Logger) (connector.Connector, error) {
 	_, err := uuid.Parse(c.Domain)

connector/ldap/ldap.go

@@ -301,6 +301,11 @@ func (c *Config) openConnector(logger *slog.Logger) (*ldapConnector, error) {
 	return &ldapConnector{*c, userSearchScope, groupSearchScope, tlsConfig, logger}, nil
 }
 
+var (
+	_ connector.PasswordConnector = (*ldapConnector)(nil)
+	_ connector.RefreshConnector  = (*ldapConnector)(nil)
+)
+
 type ldapConnector struct {
 	Config
 
@@ -312,11 +317,6 @@ type ldapConnector struct {
 	logger *slog.Logger
 }
 
-var (
-	_ connector.PasswordConnector = (*ldapConnector)(nil)
-	_ connector.RefreshConnector  = (*ldapConnector)(nil)
-)
-
 // do initializes a connection to the LDAP directory and passes it to the
 // provided function. It then performs appropriate teardown or reuse before
 // returning.

connector/linkedin/linkedin.go

@@ -49,18 +49,16 @@ type connectorData struct {
 	AccessToken string `json:"accessToken"`
 }
 
-type linkedInConnector struct {
-	oauth2Config *oauth2.Config
-	logger       *slog.Logger
-}
-
-// LinkedIn doesn't provide refresh tokens, so refresh tokens issued by Dex
-// will expire in 60 days (default LinkedIn token lifetime).
 var (
 	_ connector.CallbackConnector = (*linkedInConnector)(nil)
 	_ connector.RefreshConnector  = (*linkedInConnector)(nil)
 )
 
+type linkedInConnector struct {
+	oauth2Config *oauth2.Config
+	logger       *slog.Logger
+}
+
 // LoginURL returns an access token request URL
 func (c *linkedInConnector) LoginURL(scopes connector.Scopes, callbackURL, state string) (string, []byte, error) {
 	if c.oauth2Config.RedirectURL != callbackURL {

connector/mock/connectortest.go

@@ -29,10 +29,9 @@ func NewCallbackConnector(logger *slog.Logger) connector.Connector {
 }
 
 var (
-	_ connector.CallbackConnector = &Callback{}
-
-	_ connector.PasswordConnector = passwordConnector{}
-	_ connector.RefreshConnector  = passwordConnector{}
+	_ connector.CallbackConnector      = &Callback{}
+	_ connector.RefreshConnector       = &Callback{}
+	_ connector.TokenIdentityConnector = &Callback{}
 )
 
 // Callback is a connector that requires no user interaction and always returns the same identity.
@@ -97,6 +96,11 @@ func (c *PasswordConfig) Open(id string, logger *slog.Logger) (connector.Connect
 	return &passwordConnector{c.Username, c.Password, logger}, nil
 }
 
+var (
+	_ connector.PasswordConnector = passwordConnector{}
+	_ connector.RefreshConnector  = passwordConnector{}
+)
+
 type passwordConnector struct {
 	username string
 	password string

connector/oauth/oauth.go

@@ -16,6 +16,8 @@ import (
 	"github.com/dexidp/dex/pkg/httpclient"
 )
 
+var _ connector.CallbackConnector = (*oauthConnector)(nil)
+
 type oauthConnector struct {
 	clientID             string
 	clientSecret         string

connector/oidc/oidc.go

@@ -379,8 +379,9 @@ func (c *Config) Open(id string, logger *slog.Logger) (conn connector.Connector,
 }
 
 var (
-	_ connector.CallbackConnector = (*oidcConnector)(nil)
-	_ connector.RefreshConnector  = (*oidcConnector)(nil)
+	_ connector.CallbackConnector      = (*oidcConnector)(nil)
+	_ connector.RefreshConnector       = (*oidcConnector)(nil)
+	_ connector.TokenIdentityConnector = (*oidcConnector)(nil)
 )
 
 type oidcConnector struct {

connector/saml/saml.go

@@ -232,6 +232,11 @@ func (c *Config) openConnector(logger *slog.Logger) (*provider, error) {
 	return p, nil
 }
 
+var (
+	_ connector.SAMLConnector    = (*provider)(nil)
+	_ connector.RefreshConnector = (*provider)(nil)
+)
+
 type provider struct {
 	entityIssuer string
 	ssoIssuer    string
@@ -257,9 +262,6 @@ type provider struct {
 	logger *slog.Logger
 }
 
-// Compile-time check that provider implements RefreshConnector
-var _ connector.RefreshConnector = (*provider)(nil)
-
 // cachedIdentity stores the identity from SAML assertion for refresh token support.
 // Since SAML has no native refresh mechanism, we cache the identity obtained during
 // the initial authentication and return it on subsequent refresh requests.