--- /dev/null
+<?php
+
+namespace JsonSchema;
+
+interface SchemaStorageInterface
+{
+ /**
+ * Adds schema with given identifier
+ *
+ * @param string $id
+ * @param object $schema
+ */
+ public function addSchema($id, $schema = null);
+
+ /**
+ * Returns schema for given identifier, or null if it does not exist
+ *
+ * @param string $id
+ *
+ * @return object
+ */
+ public function getSchema($id);
+
+ /**
+ * Returns schema for given reference with all sub-references resolved
+ *
+ * @param string $ref
+ *
+ * @return object
+ */
+ public function resolveRef($ref);
+
+ /**
+ * Returns schema referenced by '$ref' property
+ *
+ * @param mixed $refSchema
+ *
+ * @return object
+ */
+ public function resolveRefSchema($refSchema);
+}