refactor: tidy structure of source files

Fixes #79

src/protocol/error.ts

@@ -0,0 +1,56 @@
+/*
+ * Copyright (C) 2019 StApps
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation, version 3.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
+/**
+ * A generic error that can be returned by the backend if somethings fails during the processing of a request
+ *
+ * @validatable
+ */
+export interface SCErrorResponse extends Error {
+  /**
+   * Additional data that describes the error
+   */
+  additionalData?: unknown;
+
+  /**
+   * HTTP status code to return this error with
+   */
+  statusCode: number;
+}
+
+/**
+ * An error that can be created by the backend during the processing of a request
+ */
+export abstract class SCError implements SCErrorResponse {
+  /**
+   * Call stack of the error
+   */
+  stack?: string;
+
+  /**
+   * Instatiate an SCError
+   *
+   * @param name Name of the error
+   * @param message Message of the error
+   * @param statusCode  HTTP status code to return this error with
+   * @param stack Set to true if a stack trace should be created
+   */
+  constructor(public name: string, public message: string, public statusCode: number, stack = false) {
+    // generate stacktrace if needed
+    if (stack) {
+      this.stack = (new Error()).stack;
+    }
+  }
+}