Add extension-point infrastructure

src/SAML11/XML/ExtensionPointInterface.php

@@ -0,0 +1,44 @@
+<?php
+
+declare(strict_types=1);
+
+namespace SimpleSAML\SAML11\XML;
+
+/**
+ * Interface for several extension points objects.
+ *
+ * @package simplesamlphp/saml11
+ */
+interface ExtensionPointInterface
+{
+    /**
+     * Get the local name for the element's xsi:type.
+     *
+     * @return string
+     */
+    public static function getXsiTypeName(): string;
+
+
+    /**
+     * Get the namespace for the element's xsi:type.
+     *
+     * @return string
+     */
+    public static function getXsiTypeNamespaceURI(): string;
+
+
+    /**
+     * Get the namespace-prefix for the element's xsi:type.
+     *
+     * @return string
+     */
+    public static function getXsiTypePrefix(): string;
+
+
+    /**
+     * Return the xsi:type value corresponding this element.
+     *
+     * @return string
+     */
+    public function getXsiType(): string;
+}

src/SAML11/XML/ExtensionPointTrait.php

@@ -0,0 +1,75 @@
+<?php
+
+declare(strict_types=1);
+
+namespace SimpleSAML\SAML11\XML;
+
+use RuntimeException;
+use SimpleSAML\Assert\Assert;
+use SimpleSAML\XML\Exception\SchemaViolationException;
+
+/**
+ * Trait for several extension points objects.
+ *
+ * @package simplesamlphp/saml11
+ */
+trait ExtensionPointTrait
+{
+    /**
+     * Get the local name for the element's xsi:type.
+     *
+     * @return string
+     */
+    public static function getXsiTypeName(): string
+    {
+        Assert::true(
+            defined('static::XSI_TYPE_NAME'),
+            self::getClassName(static::class)
+            . '::XSI_TYPE_NAME constant must be defined and set to unprefixed type for the xsi:type it represents.',
+            RuntimeException::class,
+        );
+
+        Assert::validNCName(static::XSI_TYPE_NAME, SchemaViolationException::class);
+        return static::XSI_TYPE_NAME;
+    }
+
+
+    /**
+     * Get the namespace for the element's xsi:type.
+     *
+     * @return string
+     */
+    public static function getXsiTypeNamespaceURI(): string
+    {
+        Assert::true(
+            defined('static::XSI_TYPE_NAMESPACE'),
+            self::getClassName(static::class)
+            . '::XSI_TYPE_NAMESPACE constant must be defined and set to the namespace for the xsi:type it represents.',
+            RuntimeException::class,
+        );
+
+        Assert::validURI(static::XSI_TYPE_NAMESPACE, SchemaViolationException::class);
+        return static::XSI_TYPE_NAMESPACE;
+    }
+
+
+    /**
+     * Get the namespace-prefix for the element's xsi:type.
+     *
+     * @return string
+     */
+    public static function getXsiTypePrefix(): string
+    {
+        Assert::true(
+            defined('static::XSI_TYPE_PREFIX'),
+            sprintf(
+                '%s::XSI_TYPE_PREFIX constant must be defined and set to the namespace for the xsi:type it represents.',
+                self::getClassName(static::class),
+            ),
+            RuntimeException::class,
+        );
+
+        Assert::validNCName(static::XSI_TYPE_PREFIX, SchemaViolationException::class);
+        return static::XSI_TYPE_PREFIX;
+    }
+}

src/SAML11/XML/saml/AbstractAuthorityBindingType.php

@@ -6,7 +6,7 @@
 
 use DOMElement;
 use SimpleSAML\Assert\Assert;
-use SimpleSAML\XML\Constants as C;
+use SimpleSAML\SAML11\Constants as C;
 use SimpleSAML\XML\Exception\InvalidDOMElementException;
 
 /**