'OAuth Client (Single Sign On)' WordPress Plugin Patch which diplays error on Login Page occurred During oAuth Authorization.

oauth-login-error.patch

diff -Naurw single-sign-on-client/includes/callback.php single-sign-on-client-modified/includes/callback.php
--- single-sign-on-client/includes/callback.php	2018-04-12 13:54:50.000000000 +0530
+++ single-sign-on-client-modified/includes/callback.php	2018-08-01 16:32:47.515616000 +0530
@@ -18,6 +18,23 @@
 $options       = get_option( 'wposso_options' );
 $user_redirect = wpssoc_get_user_redirect_url();
 
+// If error is present in the url, pass that error to login page
+$error_code        = isset( $_REQUEST['error'] ) ? $_REQUEST['error'] : '';
+$error_description = isset( $_REQUEST['error_description'] ) ? $_REQUEST['error_description'] : __( 'Error occurred during login. Error Code: ' ) . strtoupper( $error_code );
+
+if ( ! empty( trim( $error_code ) ) ) {
+	wp_redirect(
+		add_query_arg(
+			array(
+				'oauth_login_error_code'        => urlencode( $error_code ),
+				'oauth_login_error_description' => urlencode( $error_description ),
+			),
+			wp_login_url()
+		)
+	);
+	exit;
+}
+
 // Authenticate Check and Redirect
 if ( ! isset( $_GET['code'] ) ) {
 	$params = array(
@@ -25,7 +42,7 @@
 		'response_type' => 'code',
 		'client_id'     => $options['client_id'],
 		'client_secret' => $options['client_secret'],
-		'redirect_uri'  => site_url( '?auth=sso' )
+		'redirect_uri'  => site_url( '?auth=sso' ),
 	);
 	$params = http_build_query( $params );
 	wp_redirect( $options['server_url'] . '?' . $params );
@@ -37,7 +54,8 @@
 
 	$code       = sanitize_text_field( $_GET['code'] );
 	$server_url = $options['server_url'] . '?oauth=token';
-	$response   = wp_remote_post( $server_url, array(
+	$response   = wp_remote_post(
+		$server_url, array(
 		'method'      => 'POST',
 		'timeout'     => 45,
 		'redirection' => 5,
@@ -49,11 +67,12 @@
 			'code'          => $code,
 			'client_id'     => $options['client_id'],
 			'client_secret' => $options['client_secret'],
-			'redirect_uri'  => site_url( '?auth=sso' )
+				'redirect_uri'  => site_url( '?auth=sso' ),
 		),
 		'cookies'     => array(),
-		'sslverify'   => false
-	) );
+			'sslverify'   => false,
+		)
+	);
 
 	$tokens = json_decode( $response['body'] );
 
@@ -62,14 +81,16 @@
 	}
 
 	$server_url = $options['server_url'] . '?oauth=me&access_token=' . $tokens->access_token;
-	$response   = wp_remote_get( $server_url, array(
+	$response   = wp_remote_get(
+		$server_url, array(
 		'timeout'     => 45,
 		'redirection' => 5,
 		'httpversion' => '1.0',
 		'blocking'    => true,
 		'headers'     => array(),
-		'sslverify'   => false
-	) );
+			'sslverify'   => false,
+		)
+	);
 
 	$user_info = json_decode( $response['body'] );
 	$user_id   = username_exists( $user_info->user_login );
@@ -91,7 +112,6 @@
 			wp_redirect( $user_redirect );
 			exit;
 		}
-
 	} else {
 
 		// Already Registered... Log the User In
@@ -116,7 +136,6 @@
 			wp_redirect( $user_redirect );
 			exit;
 		}
-
 	}
 
 	exit( 'Single Sign On Failed.' );
diff -Naurw single-sign-on-client/includes/filters.php single-sign-on-client-modified/includes/filters.php
--- single-sign-on-client/includes/filters.php	2016-09-12 13:54:10.000000000 +0530
+++ single-sign-on-client-modified/includes/filters.php	2018-08-01 16:04:21.088907000 +0530
@@ -4,3 +4,4 @@
  */
 
 defined( 'ABSPATH' ) or die( 'No script kiddies please!' );
\ No newline at end of file
+
diff -Naurw single-sign-on-client/includes/functions.php single-sign-on-client-modified/includes/functions.php
--- single-sign-on-client/includes/functions.php	2018-04-12 13:54:50.000000000 +0530
+++ single-sign-on-client-modified/includes/functions.php	2018-08-01 16:38:06.894949000 +0530
@@ -34,13 +34,15 @@
  * @return [type]       [description]
  */
 function single_sign_on_login_button_shortcode( $atts ) {
-	$a = shortcode_atts( array(
+	$a = shortcode_atts(
+		array(
 		'type'   => 'primary',
 		'title'  => 'Login using Single Sign On',
 		'class'  => 'sso-button',
 		'target' => '_blank',
-		'text'   => 'Single Sign On'
-	), $atts );
+			'text'   => 'Single Sign On',
+		), $atts
+	);
 
 	return '<a class="' . $a['class'] . '" href="' . site_url( '?auth=sso' ) . '" title="' . $a['title'] . '" target="' . $a['target'] . '">' . $a['text'] . '</a>';
 }
@@ -57,3 +59,16 @@
 
 	return $user_redirect;
 }
\ No newline at end of file
+
+
+/**
+ * Display Error Message on Login page occurred during oAuth Authorization
+ */
+function wp_sso_login_errors( $errors ) {
+
+	if ( isset( $_GET['oauth_login_error_code'] ) && ! empty( $_GET['oauth_login_error_code'] ) ) {
+		$errors->add( urldecode( $_GET['oauth_login_error_code'] ), '<strong>' . $_GET['oauth_login_error_description'] . '</strong>', 'error' );
+	}
+	return $errors;
+}
+add_filter( 'wp_login_errors', 'wp_sso_login_errors', 10, 1 );
diff -Naurw single-sign-on-client/library/class-wposso-client.php single-sign-on-client-modified/library/class-wposso-client.php
--- single-sign-on-client/library/class-wposso-client.php	2018-04-12 13:54:50.000000000 +0530
+++ single-sign-on-client-modified/library/class-wposso-client.php	2018-08-01 16:11:36.180501000 +0530
@@ -17,7 +17,7 @@
 	public static $_instance = null;
 
 	/** Default Settings */
-	protected $defualt_settings = array(
+	protected $default_settings = array(
 		'client_id'            => '',
 		'client_secret'        => '',
 		'server_url'           => '',
@@ -62,7 +62,7 @@
 
 		$options = get_option( "wposso_options" );
 		if ( ! isset( $options["server_url"] ) ) {
-			update_option( "wposso_options", $this->defualt_settings );
+			update_option( "wposso_options", $this->default_settings );
 		}
 
 		$this->install();