Squashed 'third_party/pi/' content from commit d981de122

git-subtree-dir: third_party/pi
git-subtree-split: d981de1229ef899957bbe968bc8dcda02a21f477

packages/server/src/errors.ts

@@ -0,0 +1,57 @@
+import type { RemoteServiceErrorCode } from "@earendil-works/chord";
+
+type ServerOperationErrorCode =
+	| RemoteServiceErrorCode
+	| "wrong_server"
+	| "session_not_found"
+	| "session_ambiguous"
+	| "session_not_attached"
+	| "server_draining";
+
+export const INTERNAL_SERVER_ERROR_MESSAGE = "Internal server error";
+
+/** A host or lifecycle error that can safely cross the protocol boundary. */
+export class ServerError extends Error {
+	readonly code: ServerOperationErrorCode;
+
+	constructor(code: ServerOperationErrorCode, message: string) {
+		super(message);
+		this.name = "ServerError";
+		this.code = code;
+	}
+}
+
+export class WrongServerError extends ServerError {
+	constructor() {
+		super("wrong_server", "Request was addressed to another server");
+		this.name = "WrongServerError";
+	}
+}
+
+export class SessionNotFoundError extends ServerError {
+	constructor(message = "Session was not found") {
+		super("session_not_found", message);
+		this.name = "SessionNotFoundError";
+	}
+}
+
+export class SessionAmbiguousError extends ServerError {
+	constructor() {
+		super("session_ambiguous", "Session ID matches more than one session");
+		this.name = "SessionAmbiguousError";
+	}
+}
+
+export class SessionNotAttachedError extends ServerError {
+	constructor() {
+		super("session_not_attached", "Session is not attached to this client");
+		this.name = "SessionNotAttachedError";
+	}
+}
+
+export class ServerDrainingError extends ServerError {
+	constructor() {
+		super("server_draining", "Server is draining");
+		this.name = "ServerDrainingError";
+	}
+}