feat: v1.8.2 — UI tracing reads config.log_level + softer decoy detection

- src/bin/ui.rs: install_ui_tracing now takes config_level. Filter
  precedence is RUST_LOG > config.log_level > info,hyper=warn. The
  filter is wrapped in a reload::Layer; Save reinstalls it via
  apply_log_level so users don't need to restart for a level change.
  Fixes #401 (w0l4i) — config.log_level was previously dead on the
  UI binary even though the CLI honored it via init_logging.

- src/tunnel_client.rs: v1.8.1 asserted "AUTH_KEY mismatch" on the
  Apps Script placeholder body, but #404 (w0l4i) showed mixed
  success/failure on the same script_id, which rules that out. The
  body is also returned for Apps Script execution timeout, quota
  tear, internal hiccup, and ISP-side truncation. Error message now
  enumerates all four candidates and points to DIAGNOSTIC_MODE for
  disambiguation.

Cargo.lock

@@ -2222,7 +2222,7 @@ dependencies = [
 
 [[package]]
 name = "mhrv-rs"
-version = "1.8.1"
+version = "1.8.2"
 dependencies = [
  "base64 0.22.1",
  "bytes",

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "mhrv-rs"
-version = "1.8.1"
+version = "1.8.2"
 edition = "2021"
 description = "Rust port of MasterHttpRelayVPN -- DPI bypass via Google Apps Script relay with domain fronting"
 license = "MIT"

docs/changelog/v1.8.2.md

@@ -0,0 +1,6 @@
+<!-- see docs/changelog/v1.1.0.md for the file format: Persian, then `---`, then English. -->
+• اصلاح log level در UI binary (Windows + Android) ([#401](https://github.com/therealaleph/MasterHttpRelayVPN-RUST/issues/401)): قبلاً `mhrv-rs-ui` (و Android) فیلتر tracing رو فقط از `RUST_LOG` env var یا default `info,hyper=warn` می‌خوند — مقدار `log_level` در `config.json` در عمل ignore می‌شد. فرم UI combobox `log_level` داشت ولی هیچ‌جا به subscriber اعمال نمی‌شد. حالا precedence اینه: `RUST_LOG` (اگر set باشد) > `config.log_level` > `info,hyper=warn`. علاوه بر این Save در UI الان log level رو live اعمال می‌کنه (بدون نیاز به restart) از طریق reload handle. CLI `mhrv-rs` از قبل درست کار می‌کرد — این فقط fix UI bin بود.
+• پیغام تشخیص decoy ملایم‌تر — به‌جای assert AUTH_KEY mismatch، چهار علت ممکن enumerate می‌کنه ([#404](https://github.com/therealaleph/MasterHttpRelayVPN-RUST/issues/404)): @w0l4i گزارش داد همان `script_id` گاهی decoy و گاهی موفقیت برمی‌گرده در یک دقیقه — یعنی NOT AUTH_KEY mismatch (اگر بود ۱۰۰٪ fail می‌گرفت). تحقیق نشون داد body string `"The script completed but did not return anything"` اختصاصی به decoy v1.8.0 ما نیست — Apps Script همان body رو در ۴ سناریو برمی‌گردونه: (۱) AUTH_KEY mismatch (decoy ما، intentional)، (۲) Apps Script execution timeout یا quota tear، (۳) Google-side internal hiccup، (۴) ISP-side response truncation (#313 pattern). Error message v1.8.1 false positive داشت در سناریو ۲-۴. حالا پیغام: "got the v1.8.0 decoy/placeholder body — could be (1) AUTH_KEY mismatch, (2) Apps Script execution timeout/quota tear, (3) Apps Script internal hiccup, (4) ISP-side response truncation. Set DIAGNOSTIC_MODE=true to disambiguate (1) — only AUTH_KEY mismatch returns this body in diagnostic mode." کاربر action درست رو کشف می‌کنه.
+---
+• Fix log level on the UI binary (Windows + Android) ([#401](https://github.com/therealaleph/MasterHttpRelayVPN-RUST/issues/401)): previously `mhrv-rs-ui` (and Android, which uses the same JNI path) installed its tracing filter from `RUST_LOG` only — falling back to `info,hyper=warn` when unset. The `log_level` field in `config.json` was effectively ignored, even though the UI form has a combobox that writes to it. The CLI binary (`mhrv-rs`) read `config.log_level` correctly via `init_logging()`; only the UI binary was broken. New precedence: `RUST_LOG` (explicit override) > `config.log_level` (what the user picked in the form) > `info,hyper=warn` (default). The Save button now also reinstalls the filter live via a `tracing_subscriber::reload::Handle`, so users don't need to restart for a level change to take effect. RUST_LOG still wins if set at boot — explicit override beats config in both directions.
+• Soften the v1.8.1 decoy detection error message — enumerate four candidate causes instead of asserting AUTH_KEY mismatch ([#404](https://github.com/therealaleph/MasterHttpRelayVPN-RUST/issues/404)): @w0l4i reported the same `script_id` mixing decoy ERROR with successful batches inside a one-minute window — which rules out AUTH_KEY mismatch as the cause (a real mismatch fails 100% of batches against that deployment, never succeeds intermittently). Investigation showed the body string `"The script completed but did not return anything"` is **not** unique to our v1.8.0 bad-auth path — Apps Script itself returns the same body in three other unrelated cases: (2) Apps Script execution timeout or per-100s quota tear, (3) Google-side internal runtime hiccup, (4) ISP-side response truncation mid-flight (the #313 pattern). The v1.8.1 error message was a false positive in scenarios 2-4. The v1.8.2 message now reads: "got the v1.8.0 decoy/placeholder body — could be (1) AUTH_KEY mismatch (run a direct curl probe against the deployment to verify), (2) Apps Script execution timeout or per-100s quota tear (try lowering parallel_concurrency), (3) Apps Script internal hiccup (transient, retry next batch), or (4) ISP-side response truncation (#313 pattern, try a different google_ip). To distinguish (1) from the rest: set DIAGNOSTIC_MODE=true at the top of Code.gs + redeploy as new version — only AUTH_KEY mismatch returns this body in diagnostic mode." Users now have an actionable narrowing procedure instead of a confidently-wrong assertion.

src/bin/ui.rs

@@ -33,16 +33,29 @@ fn main() -> eframe::Result<()> {
     let shared = Arc::new(Shared::default());
     let (cmd_tx, cmd_rx) = std::sync::mpsc::channel::<Cmd>();
 
+    // Load the user's saved form first so we can seed the tracing filter
+    // with their saved log level. Otherwise the form's log-level combobox
+    // would only ever take effect via env var or after Save → restart, and
+    // users on the UI binary (issue #401) reasonably expect the saved
+    // config.json `log_level` to apply at boot like it does for the CLI.
+    let (form, load_err) = load_form();
+    let initial_toast = load_err.map(|e| (e, Instant::now()));
+
     // Hook tracing events into the Recent log panel. Without this every
     // tracing::info! / debug! / trace! the proxy emits gets swallowed and
     // the panel only ever shows our manual push_log calls, making the log
     // level selector look useless (issue #12 bug 2).
     //
-    // The env-filter respects RUST_LOG if set, otherwise defaults to info
+    // Filter precedence (issue #401 fix in v1.8.2):
-    // so users see routing decisions immediately without any knob-turning.
+    //   1. RUST_LOG env var if set                         — explicit override
-    // When they start the proxy and Save the config, the log level from the
+    //   2. Saved config's `log_level` (passed from form)   — what users mean
-    // config is applied to the in-process filter (see on_start below).
+    //      when they pick a level in the UI
-    install_ui_tracing(shared.clone());
+    //   3. "info,hyper=warn"                               — sensible default
+    //
+    // Save inside the running UI also installs the new filter via the
+    // reload handle (see `LOG_RELOAD` below), so users don't need to
+    // restart for a config change to take effect.
+    install_ui_tracing(shared.clone(), &form.log_level);
 
     let shared_bg = shared.clone();
     std::thread::Builder::new()
@@ -50,9 +63,6 @@ fn main() -> eframe::Result<()> {
         .spawn(move || background_thread(shared_bg, cmd_rx))
         .expect("failed to spawn background thread");
 
-    let (form, load_err) = load_form();
-    let initial_toast = load_err.map(|e| (e, Instant::now()));
-
     // Pick the renderer. Default is `glow` (OpenGL 2+) because that's
     // what we shipped through v1.0.x and it has the least binary-size
     // overhead. Users on older Windows boxes / RDP sessions / headless
@@ -993,7 +1003,12 @@ impl eframe::App for App {
             ui.horizontal(|ui| {
                 if ui.add(primary_button("Save config")).clicked() {
                     match self.form.to_config().and_then(|c| save_config(&c)) {
-                        Ok(p) => self.toast = Some((format!("Saved to {}", p.display()), Instant::now())),
+                        Ok(p) => {
+                            // Apply the new log level live so users don't have to
+                            // restart for the combobox to take effect (#401).
+                            apply_log_level(&self.form.log_level);
+                            self.toast = Some((format!("Saved to {}", p.display()), Instant::now()));
+                        }
                         Err(e) => self.toast = Some((format!("Save failed: {}", e), Instant::now())),
                     }
                 }
@@ -2193,14 +2208,19 @@ fn background_thread(shared: Arc<Shared>, rx: Receiver<Cmd>) {
 /// Install a tracing subscriber that mirrors every log event into the UI's
 /// Recent log panel.
 ///
-/// Respects `RUST_LOG` if set. Otherwise defaults to `info` — which is what
+/// Filter precedence (issue #401, v1.8.2):
-/// users mean when they pick a non-default log level in the form. (trace /
+///   1. `RUST_LOG` env var, if set
-/// debug flip too much noise for a local GUI, so the combo-box changes level
+///   2. The saved form's `log_level` (passed in from the loaded config)
-/// live via the `reload` handle that `with_env_filter` gives us but we keep
+///   3. `info,hyper=warn` as a sensible default
-/// the default boot-time level at info so first-run behavior is sensible.)
+///
-fn install_ui_tracing(shared: Arc<Shared>) {
+/// The constructed filter is wrapped in a `reload::Layer` and the handle
+/// is stashed in `LOG_RELOAD` so that a Save inside the running UI can
+/// reinstall the filter without a restart. See `apply_log_level`.
+fn install_ui_tracing(shared: Arc<Shared>, config_level: &str) {
     use tracing_subscriber::fmt::MakeWriter;
-    use tracing_subscriber::EnvFilter;
+    use tracing_subscriber::layer::SubscriberExt;
+    use tracing_subscriber::util::SubscriberInitExt;
+    use tracing_subscriber::{reload, EnvFilter};
 
     /// A MakeWriter that pushes each line into the shared log panel.
     struct UiLogWriter {
@@ -2254,19 +2274,71 @@ fn install_ui_tracing(shared: Arc<Shared>) {
         }
     }
 
-    let filter =
+    // RUST_LOG > config.log_level > "info,hyper=warn"
-        EnvFilter::try_from_default_env().unwrap_or_else(|_| EnvFilter::new("info,hyper=warn"));
+    let filter = EnvFilter::try_from_default_env().unwrap_or_else(|_| {
+        let trimmed = config_level.trim();
+        if trimmed.is_empty() {
+            EnvFilter::new("info,hyper=warn")
+        } else {
+            EnvFilter::try_new(trimmed).unwrap_or_else(|_| EnvFilter::new("info,hyper=warn"))
+        }
+    });
+
+    let (filter_layer, reload_handle) = reload::Layer::new(filter);
+    if LOG_RELOAD.set(reload_handle).is_err() {
+        // Already initialized — install_ui_tracing got called twice. Bail
+        // silently rather than panic; the existing subscriber stays live.
+        return;
+    }
 
     let writer = UiLogWriter { shared };
 
-    let _ = tracing_subscriber::fmt()
+    let fmt_layer = tracing_subscriber::fmt::layer()
-        .with_env_filter(filter)
         .with_target(false)
         .with_ansi(false)
-        .with_writer(writer)
+        .with_writer(writer);
+
+    let _ = tracing_subscriber::registry()
+        .with(filter_layer)
+        .with(fmt_layer)
         .try_init();
 }
 
+/// Reload handle for the UI's tracing EnvFilter — populated once at startup
+/// by `install_ui_tracing`. `apply_log_level` uses it to swap in a new
+/// filter when the user clicks Save with a different log level (#401).
+static LOG_RELOAD: std::sync::OnceLock<
+    tracing_subscriber::reload::Handle<
+        tracing_subscriber::EnvFilter,
+        tracing_subscriber::Registry,
+    >,
+> = std::sync::OnceLock::new();
+
+/// Reinstall the tracing filter at runtime. Called from the Save handler
+/// so the user's new `log_level` takes effect without a restart. RUST_LOG
+/// still wins if it was set at process start — explicit override beats
+/// config in both directions.
+fn apply_log_level(level: &str) {
+    use tracing_subscriber::EnvFilter;
+    let Some(handle) = LOG_RELOAD.get() else {
+        return;
+    };
+    if std::env::var_os("RUST_LOG").is_some() {
+        // RUST_LOG was set explicitly at boot — don't silently override.
+        return;
+    }
+    let trimmed = level.trim();
+    let new = if trimmed.is_empty() {
+        EnvFilter::new("info,hyper=warn")
+    } else {
+        match EnvFilter::try_new(trimmed) {
+            Ok(f) => f,
+            Err(_) => return,
+        }
+    };
+    let _ = handle.modify(|f| *f = new);
+}
+
 /// Where we drop downloaded release assets. Prefer the OS user Downloads
 /// dir (via the directories crate that's already in our tree), fall back
 /// to the user-data dir for platforms that don't expose one (edge case).

src/tunnel_client.rs

@@ -881,24 +881,36 @@ async fn fire_batch(
                 }
                 let err_msg = format!("{}", e);
                 let sid_short = &script_id[..script_id.len().min(8)];
-                // Detect the v1.8.0 bad-auth decoy HTML body. The relay layer
+                // Detect the body string we ship as the v1.8.0 bad-auth
-                // wraps any non-JSON response in `BadResponse("no json in
+                // decoy. v1.8.1 asserted "AUTH_KEY mismatch" outright, but
-                // batch response: <body prefix>")`. The decoy body string
+                // #404 (w0l4i) found the same body comes back from Apps
-                // `"The script completed but did not return anything"` is
+                // Script in 3 other unrelated cases too:
-                // distinctive — Apps Script's stock pages never include it,
+                //
-                // and our own `Code.gs` only returns it when AUTH_KEY check
+                //   1. AUTH_KEY mismatch                 — our intentional decoy
-                // fails. Surfacing this as an actionable hint saves users
+                //   2. Apps Script execution timeout/    — runtime hit 6-min
-                // (and #404 / #310 sina-b4hrm class issues) hours of
+                //      mid-call quota tear                 cap or per-100s quota
-                // staring at "no json in batch response".
+                //   3. Apps Script internal hiccup       — Google-side flake,
+                //                                          serves placeholder
+                //   4. ISP-side response truncation      — #313 pattern, the
+                //                                          response was assembled
+                //                                          but ate an RST mid-flight
+                //
+                // So we surface all four candidates instead of asserting #1.
+                // Users can flip DIAGNOSTIC_MODE=true in Code.gs to disambiguate:
+                // only #1 still returns the decoy in diagnostic mode; the
+                // others return real JSON or different errors.
                 if err_msg.contains("The script completed but did not return anything") {
                     tracing::error!(
-                        "batch failed (script {}): got the v1.8.0 bad-auth decoy — \
+                        "batch failed (script {}): got the v1.8.0 decoy/placeholder body — \
-                         your AUTH_KEY in mhrv-rs config does NOT match the AUTH_KEY \
+                         could be (1) AUTH_KEY mismatch between mhrv-rs config and Code.gs \
-                         in this deployment's Code.gs. Either fix the mismatch + \
+                         (run a direct curl probe against the deployment to verify), \
-                         redeploy as a NEW VERSION (Apps Script doesn't auto-pick-up \
+                         (2) Apps Script execution timeout or per-100s quota tear (try \
-                         AUTH_KEY edits without an explicit redeploy), or set \
+                         lowering parallel_concurrency in config), (3) Apps Script \
-                         DIAGNOSTIC_MODE=true at the top of Code.gs + redeploy to \
+                         internal hiccup (transient, retry next batch), or (4) ISP-side \
-                         see the explicit JSON `unauthorized` error during setup.",
+                         response truncation (#313 pattern, try a different google_ip). \
+                         To distinguish (1) from the rest: set DIAGNOSTIC_MODE=true at \
+                         the top of Code.gs + redeploy as new version — only AUTH_KEY \
+                         mismatch returns this body in diagnostic mode.",
                         sid_short
                     );
                 } else {