1 files changed, 33 insertions, 0 deletions
diff --git a/u/server/filter/mod.ts b/u/server/filter/mod.ts
new file mode 100644
index 0000000..bbf37df
--- /dev/null
+++ b/u/server/filter/mod.ts
@@ -0,0 +1,33 @@
+import {
+  type IEither,
+  type ITraceable,
+  LogLevel,
+  type PenguenoRequest,
+  type ServerTrace,
+} from "@emprespresso/pengueno";
+
+export enum ErrorSource {
+  USER = LogLevel.WARN,
+  SYSTEM = LogLevel.ERROR,
+}
+
+export class PenguenoError extends Error {
+  public readonly source: ErrorSource;
+  constructor(message: string, public readonly status: number) {
+    super(message);
+    this.source = Math.floor(status / 100) === 4
+      ? ErrorSource.USER
+      : ErrorSource.SYSTEM;
+  }
+}
+
+export interface RequestFilter<
+  T,
+  Err extends PenguenoError = PenguenoError,
+  RIn = ITraceable<PenguenoRequest, ServerTrace>,
+> {
+  (req: RIn): Promise<IEither<Err, T>>;
+}
+
+export * from "./method.ts";
+export * from "./json.ts";