fix(migration): keep preflight controls on canonical first-load pipeline

core/migration_ui_stability.py

@@ -2,19 +2,11 @@
 
 Older migration UI layers still exist as implementation machinery, but they may
 not infer roles, auto-select a Joomla runtime, or issue their own plans when a
-selector changes.  The guided route controller is now the sole browser owner of
-SOURCE -> TARGET -> desired Joomla -> automatic preflight.
-
-One narrow legacy behavior remains intentional: when an operator explicitly
-chooses a registered site from the historical source/target selectors, refresh
-that site's database proof immediately.  This is *not* a migration preflight and
-never chooses a role from option population; it only opens a fresh DB connection
-using the already-registered node configuration so an idle MySQL session cannot
-be mistaken for missing credentials.
-
-This final script pass also keeps fleet population placeholder-first and narrows
-connectivity observers so rendering status cannot recursively trigger probes.
-Server-side live-write gates are untouched.
+selector changes. The guided route controller is the sole browser owner.
+
+This final pass also exposes a persistent preflight control on the canonical
+pipeline. Preflight is diagnostic/read-only and must never be hidden behind a
+failed live migration.
 """
 from __future__ import annotations
 
@@ -32,19 +24,16 @@ _REGISTERED_SITE_RECONNECT = r"""
 (() => {
   if (window.__signalmeshRegisteredSiteReconnect) return;
   window.__signalmeshRegisteredSiteReconnect = true;
-
   const bind = () => {
     const src = document.querySelector('#mg-src');
     const dst = document.querySelector('#mg-dst');
     if (!src || !dst) return false;
-
     const apiBase = (typeof API_BASE !== 'undefined') ? API_BASE : location.pathname.replace(/\/[^/]*$/, '');
     const carried = () => (typeof sessionHeader === 'function' ? sessionHeader() : '');
     const phase = document.querySelector('#mg-phase');
     const msg = document.querySelector('#mg-msg');
     const adminNote = document.querySelector('#mg-admin-creds .muted');
     if (adminNote) adminNote.textContent = 'Joomla administrator only — not database credentials. Used only to install missing software on the target.';
-
     const show = (text, bad=false) => {
       if (phase) phase.textContent = text;
       if (bad && msg) {
@@ -52,44 +41,33 @@ _REGISTERED_SITE_RECONNECT = r"""
         else msg.textContent = text;
       }
     };
-
     async function reconnect(role, sel) {
       const site = String(sel.value || '').trim();
       if (!site) return;
       const seq = Number(sel.dataset.smReconnectSeq || 0) + 1;
       sel.dataset.smReconnectSeq = String(seq);
       show(`Reconnecting ${site}…`);
-
-      const q = new URLSearchParams();
-      q.set(role, site);
-      const headers = {};
-      if (carried()) headers['X-Kyklos-Session'] = carried();
-
+      const q = new URLSearchParams(); q.set(role, site);
+      const headers = {}; if (carried()) headers['X-Kyklos-Session'] = carried();
       try {
-        const r = await fetch(apiBase + '/api/migration-suite/state?' + q.toString(), {
-          credentials: 'same-origin', headers, cache: 'no-store'
-        });
+        const r = await fetch(apiBase + '/api/migration-suite/state?' + q.toString(), {credentials:'same-origin', headers, cache:'no-store'});
         const body = await r.json().catch(() => ({}));
         if (Number(sel.dataset.smReconnectSeq) !== seq) return;
         if (!r.ok) throw new Error(body?.detail || body?.message || `Reconnect failed (${r.status})`);
-
         const p = body?.[role] || null;
         const ok = role === 'source'
           ? !!(p?.read_proven && p?.inventory_proven && p?.joomla)
           : !!(p?.read_proven && p?.inventory_proven && p?.write_proven && p?.joomla);
         if (!ok) {
-          const detail = (p?.checks || []).filter(x => !x.ok).map(x => x.detail).filter(Boolean).join(' · ')
-            || p?.error || 'Joomla database proof did not pass.';
+          const detail = (p?.checks || []).filter(x => !x.ok).map(x => x.detail).filter(Boolean).join(' · ') || p?.error || 'Joomla database proof did not pass.';
           throw new Error(detail);
         }
-
         show(`${site} reconnected · Joomla ${p.joomla || '?'} · ${p.database || 'database ready'}`);
       } catch (e) {
         if (Number(sel.dataset.smReconnectSeq) !== seq) return;
         show(`Registered site ${site} could not reconnect: ${e.message || String(e)}`, true);
       }
     }
-
     for (const [role, sel] of [['source', src], ['target', dst]]) {
       if (sel.dataset.smReconnectBound === '1') continue;
       sel.dataset.smReconnectBound = '1';
@@ -97,7 +75,6 @@ _REGISTERED_SITE_RECONNECT = r"""
     }
     return true;
   };
-
   if (!bind()) {
     const obs = new MutationObserver(() => { if (bind()) obs.disconnect(); });
     obs.observe(document.documentElement, {childList:true, subtree:true});
@@ -110,69 +87,78 @@ _SAFE_MGFILL = r"""
   window.mgFill = function(sites) {
     const rows = Array.isArray(sites) ? sites : [];
     for (const [selector, role] of [['#mg-src','source'], ['#mg-dst','target']]) {
-      const sel = document.querySelector(selector);
-      if (!sel) continue;
+      const sel = document.querySelector(selector); if (!sel) continue;
       sel.innerHTML = '';
-      const ph = document.createElement('option');
-      ph.value = '';
-      ph.textContent = `— connect/select ${role} —`;
-      sel.append(ph);
+      const ph = document.createElement('option'); ph.value = ''; ph.textContent = `— connect/select ${role} —`; sel.append(ph);
       for (const row of rows) {
         const value = typeof row === 'string' ? row : (row?.site || row?.id || '');
         if (!value) continue;
-        const opt = document.createElement('option');
-        opt.value = value;
-        opt.textContent = value;
-        sel.append(opt);
+        const opt = document.createElement('option'); opt.value = value; opt.textContent = value; sel.append(opt);
       }
       sel.value = '';
     }
-    const box = document.querySelector('#migratebox');
-    if (box) box.classList.add('sm-pipeline-superseded');
+    const box = document.querySelector('#migratebox'); if (box) box.classList.add('sm-pipeline-superseded');
   };
 })();
 """
 
+_PERSISTENT_PREFLIGHT = r"""
+(() => {
+  if (window.__signalmeshPersistentPreflight) return;
+  window.__signalmeshPersistentPreflight = true;
+  const apiBase = () => (typeof API_BASE !== 'undefined') ? API_BASE : location.pathname.replace(/\/[^/]*$/, '');
+  const carried = () => (typeof sessionHeader === 'function' ? sessionHeader() : '');
+  const selected = role => document.querySelector(`[data-role-select="${role}"]`)?.value || document.querySelector(`[data-step="${role}"] .sm-pipe-choice b`)?.textContent?.trim() || '';
+  const version = () => document.querySelector('#sm-target-version')?.value || document.querySelector('[data-step="version"] .sm-pipe-choice b')?.textContent?.replace(/^Joomla\s+/,'').trim() || '';
+
+  function ensure() {
+    const root = document.querySelector('#sm-guided-pipeline');
+    if (!root) return;
+    let box = document.querySelector('#sm-persistent-preflight');
+    if (!box) {
+      box = document.createElement('section');
+      box.id = 'sm-persistent-preflight';
+      box.className = 'sm-pipe-step active';
+      box.innerHTML = `<div class="sm-pipe-num">P</div><div class="sm-pipe-body"><div class="sm-pipe-head"><h3>Preflight</h3><span class="sm-pipe-status wait" data-pf-status>AVAILABLE</span></div><div class="sm-sub">Read-only proof. Never migrates data. Select source + target; desired Joomla runtime is optional until runtime-contract validation.</div><div class="sm-actions"><button class="primary" data-pf-run>Run preflight</button></div><div data-pf-out class="sm-pipe-evidence">Waiting for source and target selection.</div></div>`;
+      root.append(box);
+    }
+    const btn = box.querySelector('[data-pf-run]');
+    if (btn && btn.dataset.bound !== '1') {
+      btn.dataset.bound = '1';
+      btn.onclick = async () => {
+        const source = selected('source'), target = selected('target'), target_version = version();
+        const out = box.querySelector('[data-pf-out]'), stat = box.querySelector('[data-pf-status]');
+        if (!source || !target) { out.textContent = 'Choose and prove both Source and Target first.'; return; }
+        btn.disabled = true; stat.textContent = 'RUNNING'; out.textContent = 'Proving connectivity, inventory, target write authority, component data mapping, extension requirements, compatibility, and runtime contract…';
+        try {
+          const q = new URLSearchParams({source,target}); if (target_version) q.set('target_version',target_version);
+          const headers = {}; if (carried()) headers['X-Kyklos-Session'] = carried();
+          const r = await fetch(apiBase() + '/api/migration-suite/state?' + q.toString(), {credentials:'same-origin',headers,cache:'no-store'});
+          const body = await r.json().catch(()=>({}));
+          if (!r.ok) throw new Error(body?.detail || body?.message || `Preflight failed (${r.status})`);
+          const blockers = body?.migration?.blockers || [];
+          const req = body?.requirements || {};
+          const totals = body?.migration?.database?.totals || {};
+          stat.textContent = blockers.length ? 'BLOCKED' : 'PROVEN';
+          out.innerHTML = `<div><b>${blockers.length ? 'Preflight found blockers' : 'Preflight passed'}</b></div><div>${Number(totals.rows_to_move||0)} client rows planned · ${Number(body?.migration?.extensions?.required||0)} extension roots</div><div>source ${req.source?'✓':'✗'} · target ${req.target?'✓':'✗'} · target write ${req.target_write?'✓':'✗'} · runtime ${target_version?(req.target_version?'✓':'✗'):'not selected yet'}</div>${blockers.map(b=>`<div class="bad">✗ ${String(b.message||b.kind||'blocker')}</div>`).join('')}`;
+        } catch(e) { stat.textContent='FAILED'; out.textContent=e.message||String(e); }
+        finally { btn.disabled=false; }
+      };
+    }
+  }
+  ensure();
+  const obs = new MutationObserver(ensure); obs.observe(document.documentElement,{childList:true,subtree:true});
+})();
+"""
+
 
 def _remove_legacy_triggers() -> None:
-    """Historical controls may render, but cannot choose or preflight a route."""
-    suite._SCRIPT = suite._SCRIPT.replace(
-        "src?.addEventListener('change',()=>{version='';load().catch(showError)});dst?.addEventListener('change',()=>{version='';load().catch(showError)});",
-        "// Guided migration owns selector decisions and preflight.",
-        1,
-    )
-    suite._SCRIPT = suite._SCRIPT.replace(
-        "if(!version)version=body.desired_target_joomla||'';",
-        "// Desired Joomla is explicit in the guided pipeline; never auto-adopt it here.",
-        1,
-    )
-    suite._SCRIPT = re.sub(
-        r"\n\s*const obs=new MutationObserver\(\(\)=>\{if\(src\?\.options\.length&&dst\?\.options\.length\)load\(\)\.catch\(\(\)=>\{\}\);\}\);if\(src&&dst\)\{obs\.observe\(src,\{childList:true\}\);obs\.observe\(dst,\{childList:true\}\);\}\n",
-        "\n",
-        suite._SCRIPT,
-        count=1,
-    )
-
-    # Strip the two anonymous explicit-selector listeners independently so this
-    # remains correct whether the source script indents them or a test fixture
-    # does not. The guided pipeline owns migration planning, but a separate
-    # reconnect-only listener is appended below for the historical selectors.
-    unified._UNIFIED_JS = unified._UNIFIED_JS.replace(
-        "src.addEventListener('change',()=>fetchPlan().catch(e=>setMsg(e.message,true)));",
-        "// Guided migration owns SOURCE changes.",
-        1,
-    )
-    unified._UNIFIED_JS = unified._UNIFIED_JS.replace(
-        "dst.addEventListener('change',()=>fetchPlan().catch(e=>setMsg(e.message,true)));",
-        "// Guided migration owns TARGET changes.",
-        1,
-    )
-    unified._UNIFIED_JS = re.sub(
-        r"\n\s*// loadFleet/mgFill populate the selects asynchronously\.[\s\S]*?if\(src\.options\.length>1&&dst\.options\.length>1\)fetchPlan\(\)\.catch\(\(\)=>\{\}\);\n",
-        "\n",
-        unified._UNIFIED_JS,
-        count=1,
-    )
+    suite._SCRIPT = suite._SCRIPT.replace("src?.addEventListener('change',()=>{version='';load().catch(showError)});dst?.addEventListener('change',()=>{version='';load().catch(showError)});", "// Guided migration owns selector decisions and preflight.", 1)
+    suite._SCRIPT = suite._SCRIPT.replace("if(!version)version=body.desired_target_joomla||'';", "// Desired Joomla is explicit in the guided pipeline; never auto-adopt it here.", 1)
+    suite._SCRIPT = re.sub(r"\n\s*const obs=new MutationObserver\(\(\)=>\{if\(src\?\.options\.length&&dst\?\.options\.length\)load\(\)\.catch\(\(\)=>\{\}\);\}\);if\(src&&dst\)\{obs\.observe\(src,\{childList:true\}\);obs\.observe\(dst,\{childList:true\}\);\}\n", "\n", suite._SCRIPT, count=1)
+    unified._UNIFIED_JS = unified._UNIFIED_JS.replace("src.addEventListener('change',()=>fetchPlan().catch(e=>setMsg(e.message,true)));", "// Guided migration owns SOURCE changes.", 1)
+    unified._UNIFIED_JS = unified._UNIFIED_JS.replace("dst.addEventListener('change',()=>fetchPlan().catch(e=>setMsg(e.message,true)));", "// Guided migration owns TARGET changes.", 1)
+    unified._UNIFIED_JS = re.sub(r"\n\s*// loadFleet/mgFill populate the selects asynchronously\.[\s\S]*?if\(src\.options\.length>1&&dst\.options\.length>1\)fetchPlan\(\)\.catch\(\(\)=>\{\}\);\n", "\n", unified._UNIFIED_JS, count=1)
     if "__signalmeshRegisteredSiteReconnect" not in unified._UNIFIED_JS:
         unified._UNIFIED_JS += "\n" + _REGISTERED_SITE_RECONNECT
 
@@ -184,10 +170,11 @@ def _install_safe_fleet_fill() -> None:
 
 def install() -> None:
     global _INSTALLED
-    if _INSTALLED:
-        return
+    if _INSTALLED: return
     _remove_legacy_triggers()
     _install_safe_fleet_fill()
     if _OLD_CONNECTIVITY in suite._SCRIPT:
         suite._SCRIPT = suite._SCRIPT.replace(_OLD_CONNECTIVITY, _NEW_CONNECTIVITY, 1)
+    if "__signalmeshPersistentPreflight" not in suite._SCRIPT:
+        suite._SCRIPT += "\n" + _PERSISTENT_PREFLIGHT
     _INSTALLED = True