NetworkInterceptor

The NetworkInterceptor intercepts and mocks outgoing fetch() calls. Useful for testing, offline scenarios, and CORS avoidance.

Quick start

const container = boot();

// Static mock
container.mockFetch("/api/users", { json: [{ name: "Alice" }] });

// Dynamic handler
container.onFetch(url => {
  if (url.includes("/health")) return { json: { ok: true } };
  return null; // pass through
});

`MockResponse`

interface MockResponse {
  status?: number; // default: 200
  headers?: Record<string, string>;
  body?: string;
  json?: unknown; // auto-serialized, overrides body
}

Container methods

Method	Description
`mockFetch(pattern, response)`	Register static mock (string or RegExp)
`onFetch(handler)`	Register dynamic handler
`network.clear()`	Remove all rules and handlers
`network.ruleCount`	Number of static rules
`network.handlerCount`	Number of dynamic handlers

Matching order

Static rules are checked first (first match wins)
Dynamic handlers are checked in registration order
If nothing matches, the request passes through to the real network

`mockResponseToFetchResponse`

Converts a MockResponse to a fetch-compatible object:

import { mockResponseToFetchResponse } from "@run0/jiki";

const resp = mockResponseToFetchResponse({ json: { ok: true } });
await resp.json(); // { ok: true }