add validation check on unique constraint on different index kinds in client

Author: fimac

lib/cipherstash/client.rb

@@ -145,6 +145,8 @@ def collections
     #
     # @raise [CipherStash::Client::Error::DecryptionFailure] if there was a problem decrypting the naming key.
     #
+    # @raise [CipherStash::Client::Error::InvalidSchemaError] if there was a problem with the format of the schema.
+    #
     def create_collection(name, schema)
       @metrics.measure_client_call("create_collection") do
         metadata = {
@@ -153,6 +155,10 @@ def create_collection(name, schema)
         }
 
         indexes = schema.fetch("indexes", {}).map do |idx_name, idx_settings|
+          if Index.invalid_unique_constraint?(idx_settings["unique"], idx_settings["kind"])
+            raise CipherStash::Client::Error::InvalidSchemaError, "Unique constraint not allowed on type #{idx_settings["kind"].inspect}" 
+          end
+
           # New match, dynamic-match, and field-dynamic-match indexes should use filter indexes.
           # ORE match indexes require specifically using a *-ore-match index.
           idx_settings["kind"] = case idx_settings["kind"]