Errors

Sloppy exposes an app-level error policy through app.useErrors(...) and typed exception mappings through app.mapError(...).

import { Config, Results, Sloppy } from "sloppy";

const app = Sloppy.create();

class NotFoundError extends Error {}

app.useErrors({
  includeDetails: Config.boolean("Errors:IncludeDetails", false),
});

app.mapError(NotFoundError, (err, ctx) =>
  Results.problem({
    status: 404,
    title: "Not found",
    detail: err.message,
    requestId: ctx.requestId,
  }, { status: 404 })
);

app.useErrors(options?)

Enables the app-host error policy for routes registered on the app.

Option	Default	Behavior
includeDetails	false	Boolean or Config.boolean(...) reference. When true, handler exception messages can be included in generated 500 responses. Provider errors stay redacted.
detail	derived from includeDetails	"never", "development", or "always". This is the lower-level detail policy used by ProblemDetails.defaults(...).
missingRoute	true	In the app test host, missing routes return a ProblemDetails-style 404 instead of plain text.
maxBodyBytes	1048576	In the app test host, larger request bodies return 413 application/problem+json.

When enabled, Sloppy maps framework failures to problem responses: unhandled exceptions use 500, validation uses 400, auth uses 401 or 403, missing routes use 404, oversized bodies use 413, unsupported media types use 415, and provider-shaped errors use a redacted 500.

If RequestId.defaults(...) runs before the error, generated problem bodies include requestId.

app.mapError(type, mapper)

Registers a typed error mapper. type must be an error constructor and mapper must return either a Results.* descriptor or a plain problem object.

Mappings run before the default unhandled-exception mapping. They do not replace the built-in validation/auth/media/body mappings.

Logging

The error policy writes one safe structured request failed log entry when ctx.log.error(...) is available. The log entry carries status, code, request ID, route metadata, and the error name. It does not include exception messages, request bodies, request headers, provider messages, tokens, cookies, or connection strings.