feat: add custom errors

src/util/errors/HttpError.ts

@@ -0,0 +1,19 @@
+/**
+ * An abstract class for all errors that could be thrown by Solid.
+ * All errors inheriting from this should fix the status code thereby hiding the HTTP internals from other components.
+ */
+export abstract class HttpError extends Error {
+  public statusCode: number;
+
+  /**
+   * Creates a new HTTP error. Subclasses should call this with their fixed status code.
+   * @param statusCode - HTTP status code needed for the HTTP response.
+   * @param name - Error name. Useful for logging and stack tracing.
+   * @param message - Message to be thrown.
+   */
+  protected constructor (statusCode: number, name: string, message: string) {
+    super(message);
+    this.statusCode = statusCode;
+    this.name = name;
+  }
+}

src/util/errors/UnsupportedHttpError.ts

@@ -0,0 +1,15 @@
+import { HttpError } from './HttpError';
+
+/**
+ * An error thrown when incoming data is not supported.
+ * Probably because an {@link AsyncHandler} returns false on the canHandle call.
+ */
+export class UnsupportedHttpError extends HttpError {
+  /**
+   * Default message is 'The given input is not supported by the server configuration.'.
+   * @param message - Optional, more specific, message.
+   */
+  public constructor (message?: string) {
+    super(400, 'UnsupportedHttpError', message || 'The given input is not supported by the server configuration.');
+  }
+}

test/unit/util/errors/UnsupportedHttpError.test.ts

@@ -0,0 +1,17 @@
+import { UnsupportedHttpError } from '../../../../src/util/errors/UnsupportedHttpError';
+
+describe('An UnsupportedHttpError', (): void => {
+  it('has status code 400.', async (): Promise<void> => {
+    const error = new UnsupportedHttpError('test');
+
+    expect(error.statusCode).toEqual(400);
+    expect(error.message).toEqual('test');
+    expect(error.name).toEqual('UnsupportedHttpError');
+  });
+
+  it('has a default message if none was provided.', async (): Promise<void> => {
+    const error = new UnsupportedHttpError();
+
+    expect(error.message).toEqual('The given input is not supported by the server configuration.');
+  });
+});