Chaos Types

Chaos Maker applies browser-side chaos to APIs your frontend already uses.

Network

Type	Config key	Effect
Failure	network.failures	Returns a configured HTTP status and body.
Latency	network.latencies	Delays matched requests by delayMs.
Abort	network.aborts	Aborts immediately or after timeout.
Corruption	network.corruptions	Rewrites response text with truncate, malformed-json, empty, or wrong-type.
CORS	network.cors	Simulates a browser network/CORS failure.

Network rules match by urlPattern substring and optional methods.

GraphQL operations can be matched inside the same network rules with graphqlOperation.

network: {
  failures: [{
    urlPattern: '/graphql',
    graphqlOperation: 'GetUser',
    statusCode: 503,
    probability: 1,
  }],
}

UI

ui.assaults targets DOM nodes by CSS selector and applies disable, hide, or remove.

ui: {
  assaults: [{ selector: 'button[type="submit"]', action: 'disable', probability: 0.5 }],
}

WebSocket

Type	Config key	Effect
Drop	websocket.drops	Drops inbound, outbound, or both directions.
Delay	websocket.delays	Delays matched messages.
Corrupt	websocket.corruptions	Rewrites text/binary payloads where supported.
Close	websocket.closes	Closes a matched socket with code, reason, and optional delay.

All probability-driven decisions use the seeded PRNG.

Service Worker

Service Worker chaos applies the same network rules inside self.fetch. Add the SW bundle to the worker, then send config from your adapter with injectSWChaos.

// classic sw.js
importScripts('/chaos-maker-sw.js');

See Service Worker Chaos for adapter-specific setup and limitations.

Server-Sent Events

Type	Config key	Effect
Drop	sse.drops	Skips inbound EventSource events.
Delay	sse.delays	Delays inbound events by delayMs.
Corrupt	sse.corruptions	Rewrites event.data.
Close	sse.closes	Closes the EventSource after optional afterMs.

SSE rules match by urlPattern; drop, delay, and corruption rules can also target eventType.