Bug? looping over variables seems to break logging

[jcollum-nutrien]

Version info:

VERSION INFO:

Artillery: 2.0.24
Node.js:   v22.15.1
OS:        darwin

Running this command:

DEBUG=http* npx artillery run tmp/loop-debug-bug.ts

DEBUG=http* npx artillery run tmp/loop-debug.ts

output from loop-debug-bug.ts:

Test run id: tkgd6_dm9f437xxh5frf7kmnfjwm6brmac5_prxn
Phase started: Warm up phase (index: 0, duration: 5s) 13:15:55(-0700)

Phase completed: Warm up phase (index: 0, duration: 5s) 13:16:00(-0700)

Phase started: Ramp up load (index: 1, duration: 5s) 13:16:00(-0700)

Phase completed: Ramp up load (index: 1, duration: 5s) 13:16:05(-0700)

--------------------------------------
Metrics for period to: 13:16:00(-0700) (width: 3.154s)
--------------------------------------

vusers.completed: .............................................................. 10
vusers.created: ................................................................ 10
vusers.created_by_name.0: ...................................................... 10

from loop-debug.ts

Test run id: tngng_drz8e9qqknx9jt8j35qhymdt9qnb7_eztr
Phase started: Warm up phase (index: 0, duration: 5s) 13:17:23(-0700)

⠸ *** GET path /dino
2025-08-27T20:17:24.180Z http:request request start: /dino
⠏ 2025-08-27T20:17:24.670Z http request: {
  "url": "http://asciiart.artillery.io:8080/dino",
  "method": "GET",
  "headers": {
    "user-agent": "Artillery (https://artillery.io)"
  }
}
*** GET path /dino
2025-08-27T20:17:24.670Z http:response {
  "server": "awselb/2.0",
  "date": "Wed, 27 Aug 2025 20:17:24 GMT",
  "content-type": "text/plain; charset=utf-8",
  "content-length": "545",
  "connection": "keep-alive"
}

[... etc]

Expected:

For some reason adding the loop seems to break the log output. I'm doing this to attempt to figure out why a POST (in a different file) isn't working, so I created this as a sample to see where the config starts breaking.

I've spent about an hour with ChatGPT and Claude to try to resolve this and it's still not working. I need to be able to loop over a list of variables, send a POST and log the output from the POST, like I would see with curl (just the basic output).

Files being used:

loop-debug.ts

export const config = {
  target: 'http://asciiart.artillery.io:8080',
  phases: [
    { duration: 5, arrivalRate: 1, rampTo: 5, name: 'Warm up phase' },
    { duration: 5, arrivalRate: 5, rampTo: 10, name: 'Ramp up load' },
    // { duration: 30, arrivalRate: 10, rampTo: 30, name: "Spike phase" },
  ],
  variables: {
    path: ['/dino', '/pony', '/armadillo'],
  },
  plugins: {
    ensure: {
      thresholds: [
        { 'http.response_time.p99': 100 },
        { 'http.response_time.p95': 75 },
      ],
    },
    apdex: { threshold: 100 },
    'metrics-by-endpoint': {},
  },
};

export const scenarios = [
  {
    flow: [
      {
        loop: [
          {
            log: '*** GET path {{ path }}',
          },
          {
            get: {
              // pick one path from variables
              url: '{{ path }}',
            },
          },
        ],
        count: 5,
      },
    ],
  },
];

loop-debug-bug.ts

export const config = {
  target: 'http://asciiart.artillery.io:8080',
  phases: [
    { duration: 5, arrivalRate: 1, rampTo: 5, name: 'Warm up phase' },
    { duration: 5, arrivalRate: 5, rampTo: 10, name: 'Ramp up load' },
    // { duration: 30, arrivalRate: 10, rampTo: 30, name: "Spike phase" },
  ],
  variables: {
    paths: ['/dino', '/pony', '/armadillo'],
  },
  plugins: {
    ensure: {
      thresholds: [
        { 'http.response_time.p99': 100 },
        { 'http.response_time.p95': 75 },
      ],
    },
    apdex: { threshold: 100 },
    'metrics-by-endpoint': {},
  },
};

export const scenarios = [
  {
    flow: [
      {
        loop: [
          { log: '*** GET path {{ $loopElement }}' },
          { get: { url: '{{ $loopElement }}' } },
        ],
        over: 'paths',
      },
    ],
  },
];