GET /flaky

Returns a failure response with probability p, otherwise 200. Both outcomes include X-Chaos-Flaky-Failed and X-Chaos-Flaky-Probability headers so clients can distinguish a chaos failure from a real one.

p Failure probability. Range: 0.0–1.0. Default: 0.5.

status HTTP status code returned on failure. Range: 100–599. Default: 500.

build a request:

failure probability 0.0–1.0 failure status 100–599 (101 excluded)

expect: Either 200 OK or the chosen failure status, decided by probability. Both responses carry X-Chaos-Flaky-Failed (true/false) and X-Chaos-Flaky-Probability.

bash

# Single call — succeeds or fails based on probability
curl -i 'https://chaos.catastrophic.io/flaky?p=0.5&status=500'

# Retry loop, stop on first success
for attempt in 1 2 3 4 5; do
    code=$(curl -s -o /dev/null -w '%{http_code}' 'https://chaos.catastrophic.io/flaky?p=0.5&status=500')
    if [ "$code" = "200" ]; then
        echo "Succeeded on attempt $attempt"
        break
    fi
    echo "Attempt $attempt failed with $code"
done

# Retry up to 5 times, stop on first success.
import urllib.request, urllib.error
url = "https://chaos.catastrophic.io/flaky?p=0.5&status=500"
for attempt in range(1, 6):
    try:
        urllib.request.urlopen(url)
        print(f"Succeeded on attempt {attempt}")
        break
    except urllib.error.HTTPError as e:
        print(f"Attempt {attempt} failed with {e.code}")

const url = "https://chaos.catastrophic.io/flaky?p=0.5&status=500";
for (let attempt = 1; attempt <= 5; attempt++) {
    const res = await fetch(url);
    if (res.ok) {
        console.log(`Succeeded on attempt ${attempt}`);
        break;
    }
    console.log(`Attempt ${attempt} failed with ${res.status}`);
}

package main

import (
    "fmt"
    "net/http"
)

func main() {
    url := "https://chaos.catastrophic.io/flaky?p=0.5&status=500"
    for attempt := 1; attempt <= 5; attempt++ {
        resp, _ := http.Get(url)
        resp.Body.Close()
        if resp.StatusCode == 200 {
            fmt.Printf("Succeeded on attempt %d\n", attempt)
            break
        }
        fmt.Printf("Attempt %d failed with %d\n", attempt, resp.StatusCode)
    }
}

// Cargo.toml: reqwest = { version = "0.12", features = ["blocking"] }
fn main() -> Result<(), Box> {
    let url = "https://chaos.catastrophic.io/flaky?p=0.5&status=500";
    let client = reqwest::blocking::Client::new();
    for attempt in 1..=5 {
        let resp = client.get(url).send()?;
        if resp.status().is_success() {
            println!("Succeeded on attempt {attempt}");
            break;
        }
        println!("Attempt {attempt} failed with {}", resp.status());
    }
    Ok(())
}

// Java 11+ HttpClient
import java.net.URI;
import java.net.http.*;

public class Flaky {
    public static void main(String[] args) throws Exception {
        var client = HttpClient.newHttpClient();
        var req = HttpRequest.newBuilder(URI.create("https://chaos.catastrophic.io/flaky?p=0.5&status=500")).build();
        for (int attempt = 1; attempt <= 5; attempt++) {
            var resp = client.send(req, HttpResponse.BodyHandlers.discarding());
            if (resp.statusCode() == 200) {
                System.out.println("Succeeded on attempt " + attempt);
                break;
            }
            System.out.println("Attempt " + attempt + " failed with " + resp.statusCode());
        }
    }
}

// .NET 6+
using var client = new HttpClient();
var url = "https://chaos.catastrophic.io/flaky?p=0.5&status=500";
for (int attempt = 1; attempt <= 5; attempt++) {
    var resp = await client.GetAsync(url);
    if (resp.IsSuccessStatusCode) {
        Console.WriteLine($"Succeeded on attempt {attempt}");
        break;
    }
    Console.WriteLine($"Attempt {attempt} failed with {(int)resp.StatusCode}");
}

require "net/http"
uri = URI("https://chaos.catastrophic.io/flaky?p=0.5&status=500")
1.upto(5) do |attempt|
    res = Net::HTTP.get_response(uri)
    if res.code == "200"
        puts "Succeeded on attempt #{attempt}"
        break
    end
    puts "Attempt #{attempt} failed with #{res.code}"
end

# Retry up to 5 times, stopping on first success.
$attempts = 0
do {
    $attempts++
    try {
        $r = Invoke-WebRequest -Uri 'https://chaos.catastrophic.io/flaky?p=0.5&status=500'
        Write-Host "Succeeded on attempt $attempts"
        break
    } catch {
        $code = $_.Exception.Response.StatusCode.value__
        Write-Host "Attempt $attempts failed with $code"
    }
} while ($attempts -lt 5)