From e6561572849aa8cb09fed08eb5e8c953f588fec0 Mon Sep 17 00:00:00 2001
From: mfahampshire <maxhampshire@pm.me>
Date: Wed, 1 Apr 2026 10:34:47 +0100
Subject: [PATCH] Make internal-dev less debug specific - Evergreen the drip
 test - Add setup config to MixFetch instance

---
 wasm/mix-fetch/internal-dev/index.html        |  42 +-
 wasm/mix-fetch/internal-dev/index.js          |  42 +-
 wasm/mix-fetch/internal-dev/package-lock.json |   4 +-
 wasm/mix-fetch/internal-dev/package.json      |   6 +-
 wasm/mix-fetch/internal-dev/worker.js         | 480 +++++++++---------
 5 files changed, 300 insertions(+), 274 deletions(-)

diff --git a/wasm/mix-fetch/internal-dev/index.html b/wasm/mix-fetch/internal-dev/index.html
index 55a727ae6c..fc63ee9f7b 100644
--- a/wasm/mix-fetch/internal-dev/index.html
+++ b/wasm/mix-fetch/internal-dev/index.html
@@ -20,6 +20,27 @@
         <label><input type="radio" name="gateway-mode" value="random" />
           Random Gateway</label>
       </div>
+      <details style="margin-top: 8px">
+        <summary style="cursor: pointer; font-size: 0.9em; color: #555">Advanced Options</summary>
+        <div style="margin-top: 6px; padding: 8px; background: #f9f9f9; font-size: 0.9em">
+          <div>
+            <label><input type="checkbox" id="opt-force-tls" checked /> Force TLS</label>
+          </div>
+          <div style="margin-top: 4px">
+            <label>Client ID: <input type="text" id="opt-client-id" value="my-client" size="20" /></label>
+          </div>
+          <div style="margin-top: 4px">
+            <label><input type="checkbox" id="opt-disable-poisson" checked /> Disable Poisson packet distribution</label>
+          </div>
+          <div style="margin-top: 4px">
+            <label><input type="checkbox" id="opt-disable-cover" checked /> Disable cover traffic</label>
+          </div>
+          <div style="margin-top: 4px">
+            <label>Request timeout (ms): <input type="number" id="opt-request-timeout" value="60000" min="1000" max="300000" style="width: 80px" /></label>
+          </div>
+        </div>
+      </details>
+
       <div style="margin-top: 8px">
         <button id="start-mixfetch">Start MixFetch</button>
         <span id="mixfetch-status" style="margin-left: 10px; color: gray">Not started</span>
@@ -79,30 +100,29 @@
       <div id="stress-drip-opts" style="display: none; margin-top: 8px; padding: 8px; background: #f9f9f9">
         <p style="margin: 0 0 4px; font-size: 0.85em; color: #666">
           Uses <code>httpbin.org/drip</code> to slowly drip bytes over a set duration,
-          keeping connections alive for a controlled time. Profiles are designed to
-          straddle the Go timeout boundary &mdash; some will finish just in time,
-          others will be mid-transfer when the timeout fires. This is how we
-          reproduce the Go runtime panic (see DEBUGGING_NOTES.md).
+          keeping connections alive for a controlled time. Profiles are computed from
+          the Go timeout value below, so they always straddle the configured boundary
+          &mdash; some finish well before the timeout, others are mid-transfer when it fires.
         </p>
         <table style="font-size: 0.9em; border-collapse: collapse">
           <tr>
             <td style="padding: 1px 10px 1px 0"><b>safe</b></td>
-            <td>30s</td>
-            <td style="padding-left: 10px; color: #666">well under 60s timeout</td>
+            <td>~50% of timeout</td>
+            <td style="padding-left: 10px; color: #666">well under the limit</td>
           </tr>
           <tr>
             <td style="padding: 1px 10px 1px 0"><b>boundary</b></td>
-            <td>55s</td>
-            <td style="padding-left: 10px; color: #666">55s server + ~10s mixnet latency = over</td>
+            <td>~92% of timeout</td>
+            <td style="padding-left: 10px; color: #666">server-side OK, but mixnet latency pushes it over</td>
           </tr>
           <tr>
             <td style="padding: 1px 10px 1px 0"><b>over</b></td>
-            <td>65s</td>
-            <td style="padding-left: 10px; color: #666">exceeds 60s timeout on its own</td>
+            <td>~108% of timeout</td>
+            <td style="padding-left: 10px; color: #666">exceeds the timeout on its own</td>
           </tr>
           <tr>
             <td style="padding: 1px 10px 1px 0"><b>slow-start</b></td>
-            <td>10s delay + 50s</td>
+            <td>~17% delay + ~83% drip</td>
             <td style="padding-left: 10px; color: #666">late first byte, then long transfer</td>
           </tr>
         </table>
diff --git a/wasm/mix-fetch/internal-dev/index.js b/wasm/mix-fetch/internal-dev/index.js
index ef99c8e98c..097ab041f4 100644
--- a/wasm/mix-fetch/internal-dev/index.js
+++ b/wasm/mix-fetch/internal-dev/index.js
@@ -48,8 +48,8 @@ class WebWorkerClient {
     };
   }
 
-  startMixFetch = (preferredGateway) => {
-    this.worker.postMessage({ kind: "StartMixFetch", args: { preferredGateway } });
+  startMixFetch = (preferredGateway, setupOpts) => {
+    this.worker.postMessage({ kind: "StartMixFetch", args: { preferredGateway, setupOpts } });
   };
 
   doFetch = (target) => {
@@ -82,12 +82,24 @@ async function main() {
     const gatewayMode = document.querySelector('input[name="gateway-mode"]:checked').value;
     const preferredGateway = gatewayMode === "default" ? DEFAULT_GATEWAY : undefined;
 
+    const setupOpts = {
+      forceTls: document.getElementById("opt-force-tls").checked,
+      clientId: document.getElementById("opt-client-id").value,
+      disablePoisson: document.getElementById("opt-disable-poisson").checked,
+      disableCover: document.getElementById("opt-disable-cover").checked,
+      requestTimeoutMs: parseInt(document.getElementById("opt-request-timeout").value, 10),
+    };
+
     document.querySelector("#start-mixfetch").disabled = true;
     document.querySelectorAll('input[name="gateway-mode"]').forEach((r) => (r.disabled = true));
     updateStatus("mixfetch-status", "Starting...", "orange");
 
+    // Sync the stress-test Go timeout to match the configured request timeout
+    document.getElementById("stress-go-timeout").value = setupOpts.requestTimeoutMs;
+
     console.log(`Starting MixFetch (${gatewayMode} gateway${preferredGateway ? `: ${preferredGateway}` : ""})...`);
-    client.startMixFetch(preferredGateway);
+    console.log("Setup options:", setupOpts);
+    client.startMixFetch(preferredGateway, setupOpts);
   };
 
   document.querySelector("#fetch-button-1").onclick = () => doFetch(1);
@@ -109,7 +121,7 @@ async function main() {
     updateStatus("stress-test-status", "Running...", "orange");
     client.setGoTimeout(goTimeoutMs);
 
-    const requests = generateStressRequests(count, mode);
+    const requests = generateStressRequests(count, mode, goTimeoutMs);
     stressTest = {
       count,
       mode,
@@ -184,14 +196,16 @@ const STRESS_PROFILES = [
   { label: "xlarge", bytes: 1048576 },
 ];
 
-const DRIP_PROFILES = [
-  { label: "safe", dripDuration: 30, dripDelay: 0, dripBytes: 100 },
-  { label: "boundary", dripDuration: 55, dripDelay: 0, dripBytes: 100 },
-  { label: "over", dripDuration: 65, dripDelay: 0, dripBytes: 100 },
-  { label: "slow-start", dripDuration: 50, dripDelay: 10, dripBytes: 100 },
-];
+function buildDripProfiles(timeoutSec) {
+  return [
+    { label: "safe",       dripDuration: Math.round(timeoutSec * 0.50), dripDelay: 0, dripBytes: 100 },
+    { label: "boundary",   dripDuration: Math.round(timeoutSec * 0.92), dripDelay: 0, dripBytes: 100 },
+    { label: "over",       dripDuration: Math.round(timeoutSec * 1.08), dripDelay: 0, dripBytes: 100 },
+    { label: "slow-start", dripDuration: Math.round(timeoutSec * 0.83), dripDelay: Math.round(timeoutSec * 0.17), dripBytes: 100 },
+  ];
+}
 
-function generateStressRequests(count, mode) {
+function generateStressRequests(count, mode, timeoutMs) {
   const requests = [];
   if (mode === "uniform") {
     const baseUrl = document.getElementById("stress-test-url").value;
@@ -199,8 +213,9 @@ function generateStressRequests(count, mode) {
       requests.push({ id: i, url: `${baseUrl}${i}`, label: "uniform", bytes: null });
     }
   } else if (mode === "drip") {
+    const dripProfiles = buildDripProfiles(timeoutMs / 1000);
     for (let i = 1; i <= count; i++) {
-      const p = DRIP_PROFILES[Math.floor(Math.random() * DRIP_PROFILES.length)];
+      const p = dripProfiles[Math.floor(Math.random() * dripProfiles.length)];
       requests.push({
         id: i,
         url: `https://httpbin.org/drip?duration=${p.dripDuration}&numbytes=${p.dripBytes}&delay=${p.dripDelay}&code=200`,
@@ -324,7 +339,8 @@ function onStressTestFetchResult(result) {
     console.log("Completion order:", stressTest.completionOrder);
 
     // Per-profile breakdown in console
-    const profileList = stressTest.mode === "drip" ? DRIP_PROFILES : STRESS_PROFILES;
+    const profileLabels = Object.keys(trackerData);
+    const profileList = profileLabels.map((label) => ({ label }));
     if (stressTest.mode === "mixed" || stressTest.mode === "drip") {
       const table = [];
       for (const profile of profileList) {
diff --git a/wasm/mix-fetch/internal-dev/package-lock.json b/wasm/mix-fetch/internal-dev/package-lock.json
index 430233c08b..053dd15a05 100644
--- a/wasm/mix-fetch/internal-dev/package-lock.json
+++ b/wasm/mix-fetch/internal-dev/package-lock.json
@@ -1,11 +1,11 @@
 {
-  "name": "create-wasm-app",
+  "name": "mix-fetch-internal-dev",
   "version": "0.1.0",
   "lockfileVersion": 3,
   "requires": true,
   "packages": {
     "": {
-      "name": "create-wasm-app",
+      "name": "mix-fetch-internal-dev",
       "version": "0.1.0",
       "license": "Apache-2.0",
       "dependencies": {
diff --git a/wasm/mix-fetch/internal-dev/package.json b/wasm/mix-fetch/internal-dev/package.json
index 7f837369f4..8358d4a4ce 100644
--- a/wasm/mix-fetch/internal-dev/package.json
+++ b/wasm/mix-fetch/internal-dev/package.json
@@ -1,7 +1,7 @@
 {
-  "name": "create-wasm-app",
+  "name": "mix-fetch-internal-dev",
   "version": "0.1.0",
-  "description": "create an app to fetch data through the mixnet",
+  "description": "Internal dev/stress-test harness for mix-fetch WASM",
   "main": "index.js",
   "bin": {
     "create-wasm-app": ".bin/create-wasm-app.js"
@@ -13,7 +13,7 @@
   },
   "repository": {
     "type": "git",
-    "url": "git+https://github.com/rustwasm/create-wasm-app.git"
+    "url": "git+https://github.com/nymtech/nym.git"
   },
   "keywords": [
     "webassembly",
diff --git a/wasm/mix-fetch/internal-dev/worker.js b/wasm/mix-fetch/internal-dev/worker.js
index eaf8a8449e..01868a178a 100644
--- a/wasm/mix-fetch/internal-dev/worker.js
+++ b/wasm/mix-fetch/internal-dev/worker.js
@@ -12,31 +12,31 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-const RUST_WASM_URL = "mix_fetch_wasm_bg.wasm"
-const GO_WASM_URL = "go_conn.wasm"
+const RUST_WASM_URL = "mix_fetch_wasm_bg.wasm";
+const GO_WASM_URL = "go_conn.wasm";
 
-importScripts('mix_fetch_wasm.js');
-importScripts('wasm_exec.js');
+importScripts("mix_fetch_wasm.js");
+importScripts("wasm_exec.js");
 
-console.log('Initializing worker');
+console.log("Initializing worker");
 
 // wasm_bindgen creates a global variable (with the exports attached) that is in scope after `importScripts`
 const {
-    default_debug,
-    no_cover_debug,
-    NymClient,
-    set_panic_hook,
-    Config,
-    GatewayEndpointConfig,
-    ClientStorage,
-    MixFetchConfig,
-    send_client_data,
-    start_new_mixnet_connection,
-    setupMixFetch,
-    disconnectMixFetch,
-    setupMixFetchWithConfig,
-    mix_fetch_initialised,
-    finish_mixnet_connection
+  default_debug,
+  no_cover_debug,
+  NymClient,
+  set_panic_hook,
+  Config,
+  GatewayEndpointConfig,
+  ClientStorage,
+  MixFetchConfig,
+  send_client_data,
+  start_new_mixnet_connection,
+  setupMixFetch,
+  disconnectMixFetch,
+  setupMixFetchWithConfig,
+  mix_fetch_initialised,
+  finish_mixnet_connection,
 } = wasm_bindgen;
 
 let client = null;
@@ -45,281 +45,271 @@ const go = new Go(); // Defined in wasm_exec.js
 var goWasm;
 let mixFetchReady = false;
 
-function sendLog(message, level = 'info') {
-    self.postMessage({
-        kind: 'Log',
-        args: { message, level },
-    });
+function sendLog(message, level = "info") {
+  self.postMessage({
+    kind: "Log",
+    args: { message, level },
+  });
 }
 
 function sendReady() {
-    self.postMessage({ kind: 'MixFetchReady' });
+  self.postMessage({ kind: "MixFetchReady" });
 }
 
 function sendError(error) {
-    self.postMessage({
-        kind: 'MixFetchError',
-        args: { error: String(error) },
-    });
+  self.postMessage({
+    kind: "MixFetchError",
+    args: { error: String(error) },
+  });
 }
 
 async function logFetchResult(res) {
-    console.log(res)
-    let text = await res.text()
-    console.log("HEADERS:     ", ...res.headers)
-    console.log("STATUS:      ", res.status)
-    console.log("STATUS TEXT: ", res.statusText)
-    console.log("OK:          ", res.ok)
-    console.log("TYPE:        ", res.type)
-    console.log("URL:         ", res.url)
-    console.log("BODYUSED:    ", res.bodyUsed)
-    console.log("REDIRECTED:  ", res.redirected)
-    console.log("TEXT:        ", text)
+  console.log(res);
+  let text = await res.text();
+  console.log("HEADERS:     ", ...res.headers);
+  console.log("STATUS:      ", res.status);
+  console.log("STATUS TEXT: ", res.statusText);
+  console.log("OK:          ", res.ok);
+  console.log("TYPE:        ", res.type);
+  console.log("URL:         ", res.url);
+  console.log("BODYUSED:    ", res.bodyUsed);
+  console.log("REDIRECTED:  ", res.redirected);
+  console.log("TEXT:        ", text);
 
-    self.postMessage({
-        kind: 'DisplayString',
-        args: {
-            rawString: text,
-        },
-    });
+  self.postMessage({
+    kind: "DisplayString",
+    args: {
+      rawString: text,
+    },
+  });
 }
 
-async function wasm_bindgenSetup() {
-    const preferredGateway = "6qQYb4ArXANU6HJDxzH4PFCUqYb39Dae2Gem2KpxescM";
-    const validator = 'https://qa-nym-api.qa.nymte.ch/api';
+/*
+ * ── Alternative MixFetch setup ──────────────────────────────
+ *
+ * Shows how to pass custom MixFetchConfig options: specific network requester
+ * address, validator URL, or debug overrides.  Uncomment and adapt if you
+ * need non-default setup for local testing.
+ *
+ *  async function wasm_bindgenSetup() {
+ *      const preferredGateway = "6qQYb4ArXANU6HJDxzH4PFCUqYb39Dae2Gem2KpxescM";
+ *      const validator = 'https://qa-nym-api.qa.nymte.ch/api';
+ *
+ *      const mixFetchNetworkRequesterAddress = "2o47bhnXWna6VEyt4mXMGQQAbXfpKmX7BkjkxUz8uQVi...";
+ *
+ *      // MixFetchConfigOpts: { id?, nymApi?, nyxd?, debug? }
+ *      const differentDebug = default_debug()
+ *      differentDebug.traffic.use_extended_packet_size = true
+ *      differentDebug.traffic.average_packet_delay_ms = 666
+ *
+ *      const config = new MixFetchConfig(mixFetchNetworkRequesterAddress, {debug: differentDebug});
+ *
+ *      // MixFetchOptsSimple: { preferredGateway?, storagePassphrase? }
+ *      await setupMixFetchWithConfig(config)
+ *  }
+ */
 
-    // local
-    const mixFetchNetworkRequesterAddress = "2o47bhnXWna6VEyt4mXMGQQAbXfpKmX7BkjkxUz8uQVi.6uQGnCqSczpXwh86NdbsCoDDXuqZQM9Uwko8GE7uC9g8@6qQYb4ArXANU6HJDxzH4PFCUqYb39Dae2Gem2KpxescM";
-    // const mixFetchNetworkRequesterAddress= "GqiGWmKRCbGQFSqH88BzLKijvZgipnqhmbNFsmkZw84t.4L8sXFuAUyUYyHZYgMdM3AtiusKnYUft6Pd8e41rrCHA@6qQYb4ArXANU6HJDxzH4PFCUqYb39Dae2Gem2KpxescM";
+async function nativeSetup(preferredGateway, setupOpts = {}) {
+  sendLog("Setting up MixFetch...");
+  if (preferredGateway) {
+    sendLog(`Using preferred gateway: ${preferredGateway}`);
+  } else {
+    sendLog("Using random gateway selection");
+  }
 
-    // STEP 1. construct config
-    // those are just some examples, there are obviously more permutations;
-    // note, the extra optional argument is of the following type:
-    // /*
-    //     export interface MixFetchConfigOpts {
-    //         id?: string;
-    //         nymApi?: string;
-    //         nyxd?: string;
-    //         debug?: DebugWasm;
-    //     }
-    //  */
-    //
-    // const debug = no_cover_debug()
-    //
-    // #1
-    // const config = new MixFetchConfig(mixFetchNetworkRequesterAddress, { id: 'my-awesome-mix-fetch-client', nymApi: validator, debug: debug} );
-    // #2
-    // const config = new MixFetchConfig(mixFetchNetworkRequesterAddress, { nymApi: validator, debug: debug} );
-    // #3
-    // const config = new MixFetchConfig(mixFetchNetworkRequesterAddress, { id: 'my-awesome-mix-fetch-client' } );
-    //
-    // #4
-    const differentDebug = default_debug()
-    const updatedTraffic = differentDebug.traffic;
-    updatedTraffic.use_extended_packet_size = true
-    updatedTraffic.average_packet_delay_ms = 666;
-    differentDebug.traffic = updatedTraffic;
+  const {
+    forceTls = true,
+    clientId = "my-client",
+    disablePoisson = true,
+    disableCover = true,
+    requestTimeoutMs = 60000,
+  } = setupOpts;
 
-    const config = new MixFetchConfig(mixFetchNetworkRequesterAddress, {debug: differentDebug});
-    //
-    // // STEP 2. setup the client
-    // // note, the extra optional argument is of the following type:
-    // /*
-    //     export interface MixFetchOptsSimple {
-    //         preferredGateway?: string;
-    //         storagePassphrase?: string;
-    //     }
-    //  */
-    // #1
-    await setupMixFetchWithConfig(config)
-    //
-    // #2
-    // await setupMixFetchWithConfig(config, { storagePassphrase: "foomp" })
-    //
-    // #3
-    // await setupMixFetchWithConfig(config, { storagePassphrase: "foomp", preferredGateway })
+  const noCoverTrafficOverride = {
+    traffic: { disableMainPoissonPacketDistribution: disablePoisson },
+    coverTraffic: { disableLoopCoverTrafficStream: disableCover },
+  };
+  const mixFetchOverride = {
+    requestTimeoutMs,
+  };
+
+  const opts = {
+    forceTls,
+    clientId,
+    clientOverride: noCoverTrafficOverride,
+    mixFetchOverride,
+  };
+
+  if (preferredGateway) {
+    opts.preferredGateway = preferredGateway;
+  }
+
+  sendLog(
+    `Setup config: forceTls=${forceTls}, clientId=${clientId}, disablePoisson=${disablePoisson}, disableCover=${disableCover}, timeout=${requestTimeoutMs}ms`
+  );
+  sendLog("Calling setupMixFetch...");
+  await setupMixFetch(opts);
+  sendLog("setupMixFetch completed");
 }
 
-async function nativeSetup(preferredGateway) {
-    sendLog('Setting up MixFetch...');
-    if (preferredGateway) {
-        sendLog(`Using preferred gateway: ${preferredGateway}`);
-    } else {
-        sendLog('Using random gateway selection');
-    }
+async function startMixFetch(preferredGateway, setupOpts) {
+  sendLog("Instantiating MixFetch...");
 
-    const noCoverTrafficOverride = {
-        traffic: {disableMainPoissonPacketDistribution: true},
-        coverTraffic: {disableLoopCoverTrafficStream: true},
-    }
-    const mixFetchOverride = {
-        requestTimeoutMs: 60000
-    }
-
-    const opts = {
-        forceTls: true,
-        clientId: "my-client",
-        clientOverride: noCoverTrafficOverride,
-        mixFetchOverride,
-    };
-
-    if (preferredGateway) {
-        opts.preferredGateway = preferredGateway;
-    }
-
-    sendLog('Calling setupMixFetch...');
-    await setupMixFetch(opts);
-    sendLog('setupMixFetch completed');
-}
-
-async function startMixFetch(preferredGateway) {
-    sendLog('Instantiating MixFetch...');
-
-    try {
-        await nativeSetup(preferredGateway);
-        mixFetchReady = true;
-        sendLog('MixFetch client running!');
-        sendReady();
-    } catch (e) {
-        sendLog('Failed to start MixFetch: ' + e, 'error');
-        sendError(e);
-    }
+  try {
+    await nativeSetup(preferredGateway, setupOpts);
+    mixFetchReady = true;
+    sendLog("MixFetch client running!");
+    sendReady();
+  } catch (e) {
+    sendLog("Failed to start MixFetch: " + e, "error");
+    sendError(e);
+  }
 }
 
 async function handleFetchPayload(target) {
-    if (!mixFetchReady) {
-        sendLog('MixFetch not ready yet', 'error');
-        return;
-    }
+  if (!mixFetchReady) {
+    sendLog("MixFetch not ready yet", "error");
+    return;
+  }
 
-    const url = target;
-    const args = {mode: "unsafe-ignore-cors"};
+  const url = target;
+  const args = { mode: "unsafe-ignore-cors" };
 
-    try {
-        sendLog(`Fetching: ${url}`);
-        const mixFetchRes = await mixFetch(url, args);
-        sendLog('Fetch completed');
-        await logFetchResult(mixFetchRes);
-    } catch (e) {
-        sendLog('Fetch request failure: ' + e, 'error');
-        console.error("mix fetch request failure: ", e);
-    }
+  try {
+    sendLog(`Fetching: ${url}`);
+    const mixFetchRes = await mixFetch(url, args);
+    sendLog("Fetch completed");
+    await logFetchResult(mixFetchRes);
+  } catch (e) {
+    sendLog("Fetch request failure: " + e, "error");
+    console.error("mix fetch request failure: ", e);
+  }
 }
 
 async function handleStressTestFetch(id, url, label) {
-    if (!mixFetchReady) {
-        sendLog('MixFetch not ready yet', 'error');
-        return;
-    }
+  if (!mixFetchReady) {
+    sendLog("MixFetch not ready yet", "error");
+    return;
+  }
 
-    const tag = `[stress #${id} ${label}]`;
-    const start = performance.now();
-    const args = { mode: "unsafe-ignore-cors" };
+  const tag = `[stress #${id} ${label}]`;
+  const start = performance.now();
+  const args = { mode: "unsafe-ignore-cors" };
 
-    try {
-        sendLog(`${tag} Fetching: ${url}`);
-        const res = await mixFetch(url, args);
-        const text = await res.text();
-        const elapsed = ((performance.now() - start) / 1000).toFixed(2);
-        sendLog(`${tag} ${res.status} OK in ${elapsed}s (${text.length} bytes)`);
-        self.postMessage({
-            kind: 'StressTestFetchResult',
-            args: { id, ok: true, status: res.status, elapsed, textLength: text.length, body: text },
-        });
-    } catch (e) {
-        const elapsed = ((performance.now() - start) / 1000).toFixed(2);
-        sendLog(`${tag} FAILED in ${elapsed}s: ${e}`, 'error');
-        self.postMessage({
-            kind: 'StressTestFetchResult',
-            args: { id, ok: false, elapsed, error: String(e) },
-        });
-    }
+  try {
+    sendLog(`${tag} Fetching: ${url}`);
+    const res = await mixFetch(url, args);
+    const text = await res.text();
+    const elapsed = ((performance.now() - start) / 1000).toFixed(2);
+    sendLog(`${tag} ${res.status} OK in ${elapsed}s (${text.length} bytes)`);
+    self.postMessage({
+      kind: "StressTestFetchResult",
+      args: {
+        id,
+        ok: true,
+        status: res.status,
+        elapsed,
+        textLength: text.length,
+        body: text,
+      },
+    });
+  } catch (e) {
+    const elapsed = ((performance.now() - start) / 1000).toFixed(2);
+    sendLog(`${tag} FAILED in ${elapsed}s: ${e}`, "error");
+    self.postMessage({
+      kind: "StressTestFetchResult",
+      args: { id, ok: false, elapsed, error: String(e) },
+    });
+  }
 }
 
 function setupMessageHandler() {
-    self.onmessage = async event => {
-        if (event.data && event.data.kind) {
-            switch (event.data.kind) {
-                case 'StartMixFetch': {
-                    const { preferredGateway } = event.data.args;
-                    await startMixFetch(preferredGateway);
-                    break;
-                }
-                case 'FetchPayload': {
-                    const { target } = event.data.args;
-                    await handleFetchPayload(target);
-                    break;
-                }
-                case 'SetGoTimeout': {
-                    const { timeoutMs } = event.data.args;
-                    sendLog(`Setting Go-side request timeout to ${timeoutMs}ms`);
-                    self.__go_rs_bridge__.goWasmSetMixFetchRequestTimeout(timeoutMs);
-                    break;
-                }
-                case 'StressTestFetch': {
-                    const { id, url, label } = event.data.args;
-                    // NOT awaited — each request runs independently,
-                    // just like separate callers in a real app
-                    handleStressTestFetch(id, url, label);
-                    break;
-                }
-            }
+  self.onmessage = async (event) => {
+    if (event.data && event.data.kind) {
+      switch (event.data.kind) {
+        case "StartMixFetch": {
+          const { preferredGateway, setupOpts } = event.data.args;
+          await startMixFetch(preferredGateway, setupOpts);
+          break;
         }
-    };
+        case "FetchPayload": {
+          const { target } = event.data.args;
+          await handleFetchPayload(target);
+          break;
+        }
+        case "SetGoTimeout": {
+          const { timeoutMs } = event.data.args;
+          sendLog(`Setting Go-side request timeout to ${timeoutMs}ms`);
+          self.__go_rs_bridge__.goWasmSetMixFetchRequestTimeout(timeoutMs);
+          break;
+        }
+        case "StressTestFetch": {
+          const { id, url, label } = event.data.args;
+          // NOT awaited — each request runs independently,
+          // just like separate callers in a real app
+          handleStressTestFetch(id, url, label);
+          break;
+        }
+      }
+    }
+  };
 }
 
-
 // TODO: look into https://www.aaron-powell.com/posts/2019-02-08-golang-wasm-5-compiling-with-webpack/
 async function loadGoWasm() {
-    const resp = await fetch(GO_WASM_URL);
+  const resp = await fetch(GO_WASM_URL);
 
-    if ('instantiateStreaming' in WebAssembly) {
-        const wasmObj = await WebAssembly.instantiateStreaming(resp, go.importObject)
-        goWasm = wasmObj.instance
-        go.run(goWasm)
-    } else {
-        const bytes = await resp.arrayBuffer()
-        const wasmObj = await WebAssembly.instantiate(bytes, go.importObject)
-        goWasm = wasmObj.instance
-        go.run(goWasm)
-    }
+  if ("instantiateStreaming" in WebAssembly) {
+    const wasmObj = await WebAssembly.instantiateStreaming(
+      resp,
+      go.importObject
+    );
+    goWasm = wasmObj.instance;
+    go.run(goWasm);
+  } else {
+    const bytes = await resp.arrayBuffer();
+    const wasmObj = await WebAssembly.instantiate(bytes, go.importObject);
+    goWasm = wasmObj.instance;
+    go.run(goWasm);
+  }
 }
 
 function setupRsGoBridge() {
-    // (note: reason for intermediate `__rs_go_bridge__` object is to decrease global scope bloat
-    // and to discourage users from trying to call those methods directly)
-    self.__rs_go_bridge__ = {}
-    self.__rs_go_bridge__.send_client_data = send_client_data
-    self.__rs_go_bridge__.start_new_mixnet_connection = start_new_mixnet_connection
-    self.__rs_go_bridge__.mix_fetch_initialised = mix_fetch_initialised
-    self.__rs_go_bridge__.finish_mixnet_connection = finish_mixnet_connection
+  // (note: reason for intermediate `__rs_go_bridge__` object is to decrease global scope bloat
+  // and to discourage users from trying to call those methods directly)
+  self.__rs_go_bridge__ = {};
+  self.__rs_go_bridge__.send_client_data = send_client_data;
+  self.__rs_go_bridge__.start_new_mixnet_connection =
+    start_new_mixnet_connection;
+  self.__rs_go_bridge__.mix_fetch_initialised = mix_fetch_initialised;
+  self.__rs_go_bridge__.finish_mixnet_connection = finish_mixnet_connection;
 }
 
 async function main() {
-    sendLog('Worker starting...');
+  sendLog("Worker starting...");
 
-    // load rust WASM package
-    sendLog('Loading Rust WASM...');
-    await wasm_bindgen(RUST_WASM_URL);
-    sendLog('Loaded Rust WASM');
+  // load rust WASM package
+  sendLog("Loading Rust WASM...");
+  await wasm_bindgen(RUST_WASM_URL);
+  sendLog("Loaded Rust WASM");
 
-    // load go WASM package
-    sendLog('Loading Go WASM...');
-    await loadGoWasm();
-    sendLog('Loaded Go WASM');
+  // load go WASM package
+  sendLog("Loading Go WASM...");
+  await loadGoWasm();
+  sendLog("Loaded Go WASM");
 
-    // sets up better stack traces in case of in-rust panics
-    set_panic_hook();
+  // sets up better stack traces in case of in-rust panics
+  set_panic_hook();
 
-    setupRsGoBridge();
+  setupRsGoBridge();
 
-    goWasmSetLogging("trace")
+  goWasmSetLogging("trace");
 
-    // Set up message handler (MixFetch will be started on demand)
-    setupMessageHandler();
+  // Set up message handler (MixFetch will be started on demand)
+  setupMessageHandler();
 
-    sendLog('Worker ready - click Start MixFetch to begin');
+  sendLog("Worker ready - click Start MixFetch to begin");
 }
 
 // Let's get started!
-main();
\ No newline at end of file
+main();