Make the acceptance page answer the operator, not the timer

Presses on Start and Continue were being swallowed. Every poll rebuilt the whole test table and the prompt buttons with innerHTML, and a button destroyed between mousedown and mouseup raises no click event at all: the press simply vanished. Measured on the page as it stood, a Start button node was replaced 13 times in 40 seconds, and with a poll landing mid-press 8 presses out of 8 were lost. Rows, prompt buttons and tool entries are now built once and afterwards only updated in place through setters that skip the write when the value has not changed; under the same test 8 presses out of 8 land. The page also felt slow because each poll re-read and re-parsed the whole result log and recomputed all 42 domain fingerprints. A result record carries its run log, so the file reaches megabytes over a campaign and the poll cost grew with it. The log now parses each line once and reads only the bytes appended since, and a fingerprint is memoized against the manifest's content hash. On the same manifest, catalog and log, one /state goes from 8.89 ms to 0.10 ms at 0.89 MB and from 41.79 ms to 0.23 ms at 10.62 MB, and no longer grows with the log. Actions now report on the press instead of on the next poll: Start greys every Start and marks the row, Continue and Abort grey themselves, and each pulls the next poll forward. /state carries an ETag so an idle page polls for a 304, the poll ticks faster during a run, and the connection is kept alive rather than handshaking per request. Keeping the connection alive exposed a hazard worth naming: a POST refused before its body was read left that body in the socket, where the next read took it for a request line. A refusal now ends the connection. forgetest is a dev-only component and can never appear in a coverage map, so this has no acceptance catalog consequence; the host tests carry the proof, including one that fails if a per-poll innerHTML rebuild ever comes back.
2026-09-27 16:51:12 -07:00 · 2026-08-21 09:49:35 -04:00
parent eaa0b0741b
commit 474e14e0e8
7 changed files with 552 additions and 87 deletions
@@ -39,6 +39,7 @@ class Test:
        self.description = description or (fn.__doc__ or "").strip()
        self.fn = fn
        self._source_sha = None
+        self._fp = (None, None)   # (manifest content sha, fingerprint)

    @property
    def source_sha(self):
@@ -51,7 +52,17 @@ class Test:
        return self._source_sha

    def fingerprint(self, manifest):
-        return _manifest.fingerprint(manifest, self.covers, extra=[self.source_sha])
+        """The domain fingerprint on this manifest, memoized by the
+        manifest's content hash: the page recomputes every test's
+        fingerprint on every poll, and a manifest never changes under a
+        running tool."""
+        key = manifest.content_sha
+        if key and self._fp[0] == key:
+            return self._fp[1]
+        fp = _manifest.fingerprint(manifest, self.covers, extra=[self.source_sha])
+        if key:
+            self._fp = (key, fp)
+        return fp

    def definition(self):
        """The gate-visible definition (no implementation, no prose)."""
@@ -13,6 +13,11 @@ One JSON object per line under the data directory (default
 Every record carries "t" (type) and "ts" (UTC, ISO 8601, seconds).
 The file is only ever appended; a corrupt line is skipped, counted, and
 reported, never repaired in place.
+
+Because the file only grows, `read` parses each line once and keeps what
+it parsed; a later call reads only the bytes appended since. A result
+record carries the whole run log, so the file reaches megabytes over a
+campaign, and the page asks for the state every second or two.
 """
 import json
 import os
@@ -35,6 +40,9 @@ class Log:
        self.path = path or os.path.join(data_dir(), "results.jsonl")
        self._lock = threading.Lock()
        self.corrupt = 0
+        self._recs = []       # every record parsed so far, in file order
+        self._offset = 0      # bytes of the file already consumed
+        self._tail = b""      # bytes past the last newline: not a record yet

    def append(self, rec):
        rec = dict(rec)
@@ -48,28 +56,54 @@ class Log:
                os.fsync(f.fileno())
        return rec

-    def read(self):
-        recs = []
+    def _forget(self):
+        """Drop what was parsed: the next read starts from the top."""
+        self._recs = []
+        self._offset = 0
+        self._tail = b""
        self.corrupt = 0
-        if not os.path.exists(self.path):
-            return recs
-        with self._lock:
-            with open(self.path, "r", encoding="utf-8") as f:
-                lines = f.readlines()
-        for line in lines:
+
+    def _consume(self, chunk):
+        """Parse the whole lines in `chunk`, holding back a partial tail."""
+        data = self._tail + chunk
+        cut = data.rfind(b"\n")
+        if cut < 0:
+            self._tail = data
+            return
+        self._tail = data[cut + 1:]
+        for line in data[:cut].split(b"\n"):
            line = line.strip()
            if not line:
                continue
            try:
-                rec = json.loads(line)
-            except ValueError:
+                rec = json.loads(line.decode("utf-8"))
+            except (ValueError, UnicodeDecodeError):
                self.corrupt += 1
                continue
            if isinstance(rec, dict) and "t" in rec:
-                recs.append(rec)
+                self._recs.append(rec)
            else:
                self.corrupt += 1
-        return recs
+
+    def read(self):
+        """Every record, in file order. Only the bytes appended since the
+        last call are parsed; a file that shrank or was replaced is read
+        again from the top."""
+        with self._lock:
+            try:
+                size = os.path.getsize(self.path)
+            except OSError:
+                self._forget()
+                return []
+            if size < self._offset:
+                self._forget()
+            if size != self._offset:
+                with open(self.path, "rb") as f:
+                    f.seek(self._offset)
+                    chunk = f.read()
+                self._offset += len(chunk)
+                self._consume(chunk)
+            return list(self._recs)

    def raw(self):
        if not os.path.exists(self.path):
@@ -10,6 +10,7 @@ plus the test's own implementation. A recorded PASS applies to a build
 exactly when the fingerprint recomputed from that build's manifest is the
 same - the same code runs on the board and in the release gate.
 """
+import functools
 import hashlib
 import json
 import os
@@ -32,9 +33,11 @@ def sha256_text(text):
    return hashlib.sha256(text.encode("utf-8")).hexdigest()


+@functools.lru_cache(maxsize=512)
 def glob_to_regex(pattern):
    """Coverage glob -> anchored regex. '**' spans directories, '*' and '?'
-    stay inside one path segment. Paths use '/' (git paths)."""
+    stay inside one path segment. Paths use '/' (git paths). Cached: the
+    catalog matches the same few hundred globs over and over."""
    out = []
    i, n = 0, len(pattern)
    while i < n:
@@ -71,6 +74,7 @@ class Manifest:
        self.platform = data.get("platform", {}) or {}
        self.image = data.get("image", {}) or {}
        self.content_sha = data.get("content_sha256")
+        self._files = {}

    @classmethod
    def load(cls, path=None):
@@ -91,12 +95,15 @@ class Manifest:
        return self.image.get("name") or "unknown"

    def files(self, component):
-        """The [path, blob] list of a component, or None if the component
-        is not in this manifest."""
+        """The (path, blob) pairs of a component, or None if the component
+        is not in this manifest. Built once per component: the manifest is
+        immutable and every coverage glob asks for the same lists."""
+        if component in self._files:
+            return self._files[component]
        c = self.components.get(component)
-        if c is None:
-            return None
-        return [tuple(x) for x in c.get("files", [])]
+        out = None if c is None else [tuple(x) for x in c.get("files", [])]
+        self._files[component] = out
+        return out

    def component_names(self):
        return sorted(self.components)
@@ -1,8 +1,16 @@
 """The single page: acceptance tab + bench tab. Self-contained (inline
 CSS/JS, ES5, no external assets); the visual identity follows the
-forgectrl control panel. State comes from GET /state on a 2 s poll; the
-catalog and the bench listing are fetched once per tab and refreshed
-after a run finishes."""
+forgectrl control panel. State comes from GET /state, polled every 2 s
+when the machine is idle and every second during a run; the catalog and
+the bench listing are fetched once per tab and refreshed after a run
+finishes.
+
+Rows, prompt buttons and tool entries are built once and thereafter only
+updated in place. A poll that rebuilt them would swallow the click it
+landed on: the button that took the mousedown would be gone before the
+mouseup, so no click event would ever be raised. Every action also greys
+its control out on the press and pulls the next poll forward, so the page
+answers the operator rather than the timer."""

 _HTML = r"""<!DOCTYPE html><html><head><meta charset='utf-8'>
 <meta name='viewport' content='width=device-width,initial-scale=1'>
@@ -81,7 +89,7 @@ pre#log{background:#1d1e26;color:#d7dae0;font-family:ui-monospace,Consolas,monos
    <div class='kv' id='banner'></div></div>
   <div id='invnote'></div><div id='msgs'></div>
   <div class='actions' style='margin-top:10px'>
-    <button class='pri' onclick='doExport()'>Export release artifact</button>
+    <button class='pri' id='exportbtn' onclick='doExport()'>Export release artifact</button>
    <a id='dljson' href='/export/acceptance.json' style='display:none'><button>acceptance.json</button></a>
    <a id='dlmd' href='/export/acceptance.md' style='display:none'><button>acceptance.md</button></a>
    <a href='/log'><button>Raw log</button></a>
@@ -120,107 +128,208 @@ pre#log{background:#1d1e26;color:#d7dae0;font-family:ui-monospace,Consolas,monos
 <script>
 var TOKEN='__TOKEN__';
 var state=null, catalog=null, catalogHash=null, bench=null, tab='acceptance', openDetails={};
-var lastRunKey=null;
+var lastRunKey=null, stateEtag=null, curPrompt=null, promptKey=null, abortSent=false;
+var pollTimer=null, polling=false, pending=0, pendingId=null, rowMsg={};
+var rowEls=null, groupsKey=null, benchEls=null, benchKey=null, benchNeedsRefresh=false;
+var PENDING_MS=6000;
+/* A poll that never answers must not wedge the loop: it times out
+   and the next one is scheduled as usual. Actions carry no timeout,
+   because a POST the server did act on must not read as a failure. */
+var POLL_TIMEOUT_MS=20000;
 var ignoreReq=false;try{ignoreReq=window.localStorage.getItem('forgetest.ignoreReq')==='1'}catch(e){}
 function $(id){return document.getElementById(id)}
-function setIgnoreReq(on){ignoreReq=!!on;try{window.localStorage.setItem('forgetest.ignoreReq',ignoreReq?'1':'0')}catch(e){}
- $('ignreq').checked=ignoreReq;$('ignreqon').innerHTML=ignoreReq?"<span class='on'>ON - prerequisites are not enforced</span>":'';if(state&&catalog)renderGroups()}
+function nowMs(){return (new Date()).getTime()}
 function esc(s){return String(s==null?'':s).replace(/[&<>"']/g,function(c){return {'&':'&amp;','<':'&lt;','>':'&gt;','"':'&quot;',"'":'&#39;'}[c]})}
-function api(method,path,body,cb){var x=new XMLHttpRequest();x.open(method,path,true);x.setRequestHeader('X-ForgeFIRM-Token',TOKEN);
+/* Touch the DOM only where the value really changed. Replacing a node
+   under the operator's finger loses the click: the button that took the
+   mousedown is gone before the mouseup, so no click event is ever
+   raised, and the press does nothing. Nothing on a poll may rebuild a
+   control that is only sitting there unchanged. */
+function setHtml(e,h){if(e&&e.__h!==h){e.__h=h;e.innerHTML=h}}
+function setText(e,t){if(e&&e.__t!==t){e.__t=t;e.textContent=t}}
+function setDis(e,d){if(e&&e.disabled!==d)e.disabled=d}
+function setProp(e,k,v){if(e&&e[k]!==v)e[k]=v}
+function api(method,path,body,cb,hdrs,timeoutMs){var x=new XMLHttpRequest();x.open(method,path,true);
+ if(timeoutMs)x.timeout=timeoutMs;
+ x.setRequestHeader('X-ForgeFIRM-Token',TOKEN);
+ if(hdrs){for(var k in hdrs){if(hdrs.hasOwnProperty(k))x.setRequestHeader(k,hdrs[k])}}
 if(body!==undefined&&body!==null){x.setRequestHeader('Content-Type','application/json')}
- x.onreadystatechange=function(){if(x.readyState!==4)return;var d=null;try{d=JSON.parse(x.responseText)}catch(e){d={error:x.responseText}}cb(x.status,d)};
+ x.onreadystatechange=function(){if(x.readyState!==4)return;var d=null;try{d=JSON.parse(x.responseText)}catch(e){d={error:x.responseText}}cb(x.status,d,x)};
 x.send(body===undefined||body===null?null:JSON.stringify(body))}
+/* The state poll. It carries the last ETag, so an unchanged state costs
+   a 304 and no re-render; a run gets a faster tick, and every action
+   pulls the next poll forward instead of waiting out the interval. */
+function pollDelay(){return (state&&state.running)?1000:2000}
+function schedule(ms){if(pollTimer)window.clearTimeout(pollTimer);pollTimer=window.setTimeout(poll,ms)}
+function kick(){schedule(120)}
+function poll(){if(polling){schedule(150);return}polling=true;
+ /* While an action is still in flight the state is asked for in full:
+    a 304 would skip the render that releases the greyed-out buttons. */
+ var h=(stateEtag&&!pending)?{'If-None-Match':stateEtag}:null;
+ api('GET','/state',null,function(s,d,x){polling=false;
+  if(s===200){stateEtag=x.getResponseHeader('ETag');state=d;
+   if(!catalog||catalogHash!==d.catalog_hash){loadCatalog(render)}else{render()}}
+  schedule(pollDelay())},h,POLL_TIMEOUT_MS)}
 function showTab(t){tab=t;$('tab-acceptance').className=t==='acceptance'?'on':'';$('tab-bench').className=t==='bench'?'on':'';
 $('pane-acceptance').style.display=t==='acceptance'?'':'none';$('pane-bench').style.display=t==='bench'?'':'none';
 if(t==='bench'&&!bench)loadBench()}
-function setMsg(id,txt,err){var e=$(id);e.innerHTML=txt?"<div class='"+(err?'err':'msg')+"'>"+esc(txt)+"</div>":''}
+function setMsg(id,txt,err){setHtml($(id),txt?"<div class='"+(err?'err':'msg')+"'>"+esc(txt)+"</div>":'')}
 function loadCatalog(cb){api('GET','/catalog',null,function(s,d){if(s===200){catalog=d.tests;catalogHash=d.catalog_hash;if(cb)cb()}})}
-function loadBench(){api('GET','/bench',null,function(s,d){if(s===200){bench=d;renderBench()}})}
-function poll(){api('GET','/state',null,function(s,d){if(s===200){state=d;if(!catalog||catalogHash!==d.catalog_hash){loadCatalog(render)}else{render()}}
- setTimeout(poll,2000)})}
+function loadBench(){api('GET','/bench',null,function(s,d){if(s===200){bench=d;benchKey=null;renderBench()}})}
+function setIgnoreReq(on){ignoreReq=!!on;try{window.localStorage.setItem('forgetest.ignoreReq',ignoreReq?'1':'0')}catch(e){}
+ $('ignreq').checked=ignoreReq;setHtml($('ignreqon'),ignoreReq?"<span class='on'>ON - prerequisites are not enforced</span>":'');
+ if(state&&catalog)renderGroups()}
+/* A start already sent but not yet seen in the state counts as busy, so
+   the buttons grey out on the click rather than on the next poll. The
+   window is capped in case the answer never arrives. */
+function isBusy(){if(state&&state.running)return true;
+ return !!(pending&&(nowMs()-pending)<PENDING_MS)}
 function fmtTs(t){return t?t.replace('T',' ').replace('Z',' UTC'):'-'}
 function render(){if(!state||!catalog)return;
- var m=state.manifest||{};$('hdrver').textContent=(m.version||'?');$('hdrsub').textContent=m.image||'';
- var a=$('auth');a.textContent='Release authorized: '+(state.authorized?'YES':'NO');a.className='auth'+(state.authorized?' yes':'');
+ if(state.running){pending=0;pendingId=null}
+ var m=state.manifest||{};setText($('hdrver'),(m.version||'?'));setText($('hdrsub'),m.image||'');
+ var a=$('auth');setText(a,'Release authorized: '+(state.authorized?'YES':'NO'));setProp(a,'className','auth'+(state.authorized?' yes':''));
 var c=state.campaign,cn=state.counts||{};var b='';
 b+='<b>'+cn.satisfied+'</b> of <b>'+cn.total+'</b> satisfied ('+cn.inherited+' inherited), <b>'+cn.required+'</b> required<br>';
 b+=c?('campaign <span class="mono">'+esc(c.id)+'</span> opened '+esc(fmtTs(c.ts))):('no open campaign'+(state.closed_by?(' (last one closed by '+esc(state.closed_by)+')'):'')+' - the first Start opens one');
 b+='<br>manifest identity <span class="mono">'+esc((m.sha||'').slice(0,16))+'</span> &middot; catalog <span class="mono">'+esc((state.catalog_hash||'').slice(0,12))+'</span>';
 if(state.log_corrupt)b+='<br><span style="color:var(--red)">'+state.log_corrupt+' corrupt log line(s) skipped</span>';
- $('banner').innerHTML=b;
- var inv=state.invalidate;$('invnote').innerHTML=inv?"<div class='note'>Full campaign required since "+esc(fmtTs(inv.ts))+": "+esc(inv.reason)+"</div>":'';
- var ms='';(state.messages||[]).forEach(function(x){ms+="<div class='note'>"+esc(x)+"</div>"});$('msgs').innerHTML=ms;
- renderGroups();renderRun()}
-function renderGroups(){var groups={},order=[];catalog.forEach(function(t){if(!groups[t.subsystem]){groups[t.subsystem]=[];order.push(t.subsystem)}groups[t.subsystem].push(t)});
- var busy=!!state.running;var h='';
+ setHtml($('banner'),b);
+ var inv=state.invalidate;setHtml($('invnote'),inv?"<div class='note'>Full campaign required since "+esc(fmtTs(inv.ts))+": "+esc(inv.reason)+"</div>":'');
+ var ms='';(state.messages||[]).forEach(function(x){ms+="<div class='note'>"+esc(x)+"</div>"});setHtml($('msgs'),ms);
+ renderGroups();renderRun();if(bench)renderBench()}
+/* The rows are built once for a given catalog and then only updated in
+   place: a poll never rewrites the table, so a Start button survives the
+   press that is landing on it. */
+function renderGroups(){var ids=[];catalog.forEach(function(t){ids.push(t.id)});
+ var sig=catalogHash+'|'+ids.join(',');
+ if(sig!==groupsKey){groupsKey=sig;buildGroups()}
+ updateGroups()}
+function buildGroups(){var groups={},order=[];
+ catalog.forEach(function(t){if(!groups[t.subsystem]){groups[t.subsystem]=[];order.push(t.subsystem)}groups[t.subsystem].push(t)});
+ var h='';
 order.forEach(function(g){h+="<div class='card grp'><h2>"+esc(g)+"</h2><table><tr><th>Test</th><th>Kind</th><th>Status</th><th>Last result</th><th></th></tr>";
-  groups[g].forEach(function(t){var s=state.tests[t.id]||{};var badges='';
+  groups[g].forEach(function(t){var d=esc(t.id);var badges='';
   if(t.always)badges+="<span class='badge core'>core</span>";badges+="<span class='badge "+esc(t.kind)+"'>"+esc(t.kind)+"</span>";
   if(t.hardware==='takeover')badges+="<span class='badge takeover'>takeover</span>";
-   var st="<span class='st "+esc(s.status)+"'>"+esc(s.status||'none')+"</span>";
-   if(s.required&&s.status!=='running')st+="<br><span class='req'>required: "+esc(s.reason)+"</span>";
-   var last=s.last?(esc(s.last.result)+' '+esc(fmtTs(s.last.ts))):'-';
-   if(s.status==='inherited'&&s.origin)last+="<br><span class='tid'>from "+esc(s.origin.campaign)+" on "+esc(s.origin.image)+"</span>";
-   var unmet=s.requires_met===false;var canStart=!busy&&(!unmet||ignoreReq);
-   var why=busy?'a run is in progress':(unmet?((ignoreReq?'prerequisites overridden - needs: ':'needs: ')+(s.missing_requires||[]).join(', ')):'');
-   var startBtn="<button class='pri' "+(canStart?'':'disabled')+" title='"+esc(why)+"' onclick='startTest(\""+esc(t.id)+"\")'>Start</button>";
-   if(unmet)startBtn+="<div class='req"+(ignoreReq?' over':'')+"'>"+(ignoreReq?'unmet: ':'needs: ')+esc((s.missing_requires||[]).join(', '))+"</div>";
-   var det="<div class='details"+(openDetails[t.id]?' on':'')+"' id='det-"+esc(t.id)+"'>"+esc(t.description||'')+
+   var det="<div class='details"+(openDetails[t.id]?' on':'')+"' id='det-"+d+"'>"+esc(t.description||'')+
     (t.steps&&t.steps.length?"<br><b>Operator steps:</b><ol>"+t.steps.map(function(x){return '<li>'+esc(x)+'</li>'}).join('')+"</ol>":'')+
     "<b>Requires:</b> "+esc((t.requires||[]).join(', ')||'-')+"<br><b>Covers:</b> "+esc((t.covers||[]).map(function(c){return c[0]+':'+c[1]}).join(', ')||'-')+
-     "<br><b>Fingerprint:</b> <span class='mono'>"+esc((s.fingerprint||'').slice(0,16))+"</span> &middot; est. "+esc(t.est_min)+" min"+
-     (s.last?"<br><a href='/result?test="+encodeURIComponent(t.id)+"&ts="+encodeURIComponent(s.last.ts)+"'>last result record</a>":'')+"</div>";
-   h+="<tr><td><div>"+esc(t.title)+"</div><div class='tid'>"+esc(t.id)+" <a href='#' onclick='toggleDet(\""+esc(t.id)+"\");return false'>details</a></div>"+det+"</td><td>"+badges+"</td><td>"+st+"</td><td>"+last+"</td><td>"+startBtn+"</td></tr>"});
+     "<br><span id='detdyn-"+d+"'></span></div>";
+   h+="<tr><td><div>"+esc(t.title)+"</div><div class='tid'>"+d+" <a href='#' onclick='toggleDet(\""+d+"\");return false'>details</a></div>"+det+
+     "</td><td>"+badges+"</td><td id='st-"+d+"'></td><td id='last-"+d+"'></td>"+
+     "<td><button class='pri' id='btn-"+d+"' onclick='startTest(\""+d+"\")'>Start</button>"+
+     "<div id='unmet-"+d+"'></div><div id='note-"+d+"'></div></td></tr>"});
  h+="</table></div>"});
- $('groups').innerHTML=h}
+ $('groups').innerHTML=h;rowEls={};
+ catalog.forEach(function(t){rowEls[t.id]={st:$('st-'+t.id),last:$('last-'+t.id),btn:$('btn-'+t.id),
+  unmet:$('unmet-'+t.id),note:$('note-'+t.id),detdyn:$('detdyn-'+t.id)}})}
+function updateGroups(){if(!rowEls||!state)return;var busy=isBusy();
+ catalog.forEach(function(t){var e=rowEls[t.id];if(!e)return;var s=state.tests[t.id]||{};
+  var st;
+  if(pendingId===t.id&&isBusy()&&!state.running){st="<span class='st running'>starting&hellip;</span>"}
+  else{st="<span class='st "+esc(s.status)+"'>"+esc(s.status||'none')+"</span>";
+   if(s.required&&s.status!=='running')st+="<br><span class='req'>required: "+esc(s.reason)+"</span>"}
+  setHtml(e.st,st);
+  var last=s.last?(esc(s.last.result)+' '+esc(fmtTs(s.last.ts))):'-';
+  if(s.status==='inherited'&&s.origin)last+="<br><span class='tid'>from "+esc(s.origin.campaign)+" on "+esc(s.origin.image)+"</span>";
+  setHtml(e.last,last);
+  var unmet=s.requires_met===false;var can=!busy&&(!unmet||ignoreReq);
+  setDis(e.btn,!can);
+  setProp(e.btn,'title',busy?'a run is in progress':(unmet?((ignoreReq?'prerequisites overridden - needs: ':'needs: ')+(s.missing_requires||[]).join(', ')):''));
+  setProp(e.unmet,'className','req'+(ignoreReq?' over':''));
+  setHtml(e.unmet,unmet?((ignoreReq?'unmet: ':'needs: ')+esc((s.missing_requires||[]).join(', '))):'');
+  setHtml(e.note,rowMsg[t.id]?"<div class='err'>"+esc(rowMsg[t.id])+"</div>":'');
+  setHtml(e.detdyn,"<b>Fingerprint:</b> <span class='mono'>"+esc((s.fingerprint||'').slice(0,16))+"</span> &middot; est. "+esc(t.est_min)+" min"+
+   (s.last?"<br><a href='/result?test="+encodeURIComponent(t.id)+"&ts="+encodeURIComponent(s.last.ts)+"'>last result record</a>":''))})}
 function toggleDet(id){openDetails[id]=!openDetails[id];var e=$('det-'+id);if(e)e.className='details'+(openDetails[id]?' on':'')}
 function renderRun(){var r=state.running||state.last_run;var key=r?(r.kind+':'+r.id+':'+r.started):null;
- if(!r){$('runhead').textContent='idle';$('log').textContent='';$('prompt').style.display='none';$('abortbtn').disabled=true;$('runtitle').textContent='Run';return}
- $('runtitle').textContent=(r.kind==='bench'?'Bench: ':'Test: ')+r.title;
- var hd=r.id+' &middot; started '+esc(fmtTs(r.started))+' &middot; '+r.elapsed_s+' s';
+ if(key!==lastRunKey)abortSent=false;
+ if(!r){setText($('runhead'),'idle');setText($('log'),'');$('prompt').style.display='none';
+  curPrompt=null;promptKey=null;setDis($('abortbtn'),true);setText($('runtitle'),'Run');lastRunKey=null;return}
+ setText($('runtitle'),(r.kind==='bench'?'Bench: ':'Test: ')+r.title);
+ var hd=esc(r.id)+' &middot; started '+esc(fmtTs(r.started))+' &middot; '+r.elapsed_s+' s';
 if(r.finished){hd+=' &middot; <b class="st '+(r.finished.result==='PASS'||r.finished.result==='OK'?'pass':'fail')+'">'+esc(r.finished.result)+'</b>'+(r.finished.message?' - '+esc(r.finished.message):'')}
 else if(r.aborting){hd+=' &middot; <b class="st stale">aborting</b>'}
- $('runhead').innerHTML=hd;
- var lg=$('log');var atBottom=lg.scrollTop+lg.clientHeight>=lg.scrollHeight-20;lg.textContent=(r.dropped?('... '+r.dropped+' earlier lines dropped\n'):'')+r.log.join('\n');
- if(atBottom||key!==lastRunKey)lg.scrollTop=lg.scrollHeight;lastRunKey=key;
- if(r.prompt&&!r.finished){$('prompt').style.display='';$('promptq').textContent=r.prompt.question;var pb='';
-  r.prompt.options.forEach(function(o){pb+="<button class='pri' onclick='answer(\""+esc(r.prompt.id)+"\",\""+esc(o)+"\")'>"+esc(o)+"</button>"});$('promptb').innerHTML=pb}
- else{$('prompt').style.display='none'}
- $('abortbtn').disabled=!!r.finished;
+ setHtml($('runhead'),hd);
+ var lg=$('log');var txt=(r.dropped?('... '+r.dropped+' earlier lines dropped\n'):'')+r.log.join('\n');
+ if(lg.__t!==txt){var atBottom=lg.scrollTop+lg.clientHeight>=lg.scrollHeight-20;
+  lg.__t=txt;lg.textContent=txt;if(atBottom||key!==lastRunKey)lg.scrollTop=lg.scrollHeight}
+ lastRunKey=key;
+ /* The prompt buttons are rebuilt only when the prompt itself changes -
+    they are the ones the operator stares at before pressing. */
+ if(r.prompt&&!r.finished){var pk=r.prompt.id+'|'+r.prompt.question+'|'+r.prompt.options.length+':'+r.prompt.options.join(',');
+  if(pk!==promptKey){promptKey=pk;curPrompt=r.prompt;
+   $('promptq').textContent=r.prompt.question;var pb='';
+   r.prompt.options.forEach(function(o,i){pb+="<button class='pri' onclick='answerIdx("+i+")'>"+esc(o)+"</button>"});
+   $('promptb').innerHTML=pb;$('promptb').__h=pb;$('prompt').style.display=''}}
+ else if(promptKey!==null){promptKey=null;curPrompt=null;$('prompt').style.display='none'}
+ setDis($('abortbtn'),!!r.finished||abortSent||!!r.aborting);
 if(r.finished&&tab==='bench'&&r.kind==='bench'&&benchNeedsRefresh){benchNeedsRefresh=false;loadBench()}}
-var benchNeedsRefresh=false;
 function findTest(id){for(var i=0;i<catalog.length;i++)if(catalog[i].id===id)return catalog[i];return null}
-function startTest(id){var t=findTest(id);var body={test:id};
+function startTest(id){if(isBusy())return;var t=findTest(id);var body={test:id};
 if(ignoreReq)body.ignore_requires=true;
 if(t&&t.kind==='live'){if(!confirmLive())return;body.ack_live=true}
- api('POST','/start',body,function(s,d){setMsg('actmsg',d.message||d.error,s!==200)})}
+ pending=nowMs();pendingId=id;rowMsg={};updateGroups();
+ setMsg('actmsg','starting '+id+'...');
+ api('POST','/start',body,function(s,d){
+  if(s!==200){pending=0;pendingId=null;rowMsg[id]=d.message||d.error;updateGroups()}
+  setMsg('actmsg',d.message||d.error,s!==200);kick()})}
 function confirmLive(){return window.confirm('LIVE LASER TEST.\n\nConfirm before starting:\n - eye protection on, everyone in the room\n - fire watch present, extinguisher at hand\n - exhaust running, lid closed, scrap in place\n - you will press the physical button to arm when prompted\n\nStart the test?')}
-function answer(pid,v){api('POST','/answer',{prompt_id:pid,value:v},function(s,d){if(s!==200)setMsg('actmsg',d.message||d.error,true)})}
-function doAbort(){api('POST','/abort',{},function(s,d){setMsg('actmsg',d.message||d.error,s!==200)})}
-function doExport(){api('POST','/export',{},function(s,d){if(s===200){setMsg('actmsg','exported: authorized='+d.authorized+', sha256 '+d.sha256.slice(0,16)+' - download below');$('dljson').style.display='';$('dlmd').style.display=''}else setMsg('actmsg',d.message||d.error,true)})}
+function promptBusy(on){var b=$('promptb').getElementsByTagName('button');for(var i=0;i<b.length;i++)setDis(b[i],on)}
+function answerIdx(i){if(!curPrompt)return;var p=curPrompt,v=p.options[i];
+ promptBusy(true);setMsg('actmsg','answer sent: '+v);
+ api('POST','/answer',{prompt_id:p.id,value:v},function(s,d){
+  if(s!==200){promptBusy(false);setMsg('actmsg',d.message||d.error,true)}kick()})}
+function doAbort(){var b=$('abortbtn');if(b.disabled)return;abortSent=true;setDis(b,true);
+ setMsg('actmsg','aborting...');
+ api('POST','/abort',{},function(s,d){if(s!==200)abortSent=false;setMsg('actmsg',d.message||d.error,s!==200);kick()})}
+function doExport(){var b=$('exportbtn');if(b.disabled)return;setDis(b,true);setMsg('actmsg','exporting...');
+ api('POST','/export',{},function(s,d){setDis(b,false);
+  if(s===200){setMsg('actmsg','exported: authorized='+d.authorized+', sha256 '+d.sha256.slice(0,16)+' - download below');$('dljson').style.display='';$('dlmd').style.display=''}
+  else setMsg('actmsg',d.message||d.error,true)})}
 function toggleInv(){var f=$('invform');f.style.display=f.style.display==='none'?'':'none'}
 function doInvalidate(){var r=$('invreason').value;if(!r){setMsg('actmsg','a reason is required',true);return}
- api('POST','/invalidate',{reason:r},function(s,d){setMsg('actmsg',d.message||d.error,s!==200);if(s===200){$('invform').style.display='none';$('invreason').value=''}})}
-function doReset(){api('POST','/reset',{reason:'operator reset from the page'},function(s,d){setMsg('actmsg',d.message||d.error,s!==200)})}
-function renderBench(){if(!bench)return;var busy=!!(state&&state.running);var groups={dry:[],takeover:[],live:[],scope:[]};
+ api('POST','/invalidate',{reason:r},function(s,d){setMsg('actmsg',d.message||d.error,s!==200);
+  if(s===200){$('invform').style.display='none';$('invreason').value=''}kick()})}
+function doReset(){api('POST','/reset',{reason:'operator reset from the page'},function(s,d){setMsg('actmsg',d.message||d.error,s!==200);kick()})}
+/* Same rule as the acceptance rows: the tool list is built once and then
+   only updated, so a run starting never rewrites the arg fields the
+   operator has typed into or the button being pressed. */
+function renderBench(){if(!bench)return;var ids=[];
+ bench.tools.forEach(function(t){ids.push(t.id+':'+(t.ported?1:0)+(t.installed?1:0))});
+ var sig=ids.join(',');
+ if(sig!==benchKey){benchKey=sig;buildBench()}
+ updateBench()}
+function buildBench(){var groups={dry:[],takeover:[],live:[],scope:[]};
 bench.tools.forEach(function(t){(groups[t.safety]||(groups[t.safety]=[])).push(t)});var h='';
 ['dry','takeover','scope','live'].forEach(function(g){if(!groups[g]||!groups[g].length)return;
  h+="<div class='card grp'><h2>"+esc(g)+"</h2>";
-  groups[g].forEach(function(t){var can=t.ported&&t.installed&&!busy;var why=!t.ported?'not yet ported to the bench page':(!t.installed?'script not installed on this image':(busy?'a run is in progress':''));
+  groups[g].forEach(function(t){var d=esc(t.id);
   h+="<div class='tool' style='border-bottom:1px solid var(--line);padding:8px 0'><div><b>"+esc(t.title)+"</b> <span class='tid'>"+esc(t.script)+"</span> <span class='badge'>"+esc(t.where)+"</span>"+(t.ported?'':"<span class='badge'>unported</span>")+"</div>";
   h+="<div class='hint' style='margin:2px 0 4px'>"+esc(t.desc)+"</div>";
   if(t.args&&t.args.length){h+="<div class='argrow'>";t.args.forEach(function(a){var iid='arg-'+t.id+'-'+a.name;
     if(a.type==='choice'){h+="<label>"+esc(a.name)+" <select id='"+iid+"'>"+a.choices.map(function(c){return "<option"+(c===a.default?' selected':'')+">"+esc(c)+"</option>"}).join('')+"</select></label>"}
     else{h+="<label>"+esc(a.name)+" <input type='"+(a.type==='str'?'text':'number')+"' step='any' id='"+iid+"' value='"+esc(a.default==null?'':a.default)+"' title='"+esc(a.help)+"' style='width:90px'></label>"}});h+="</div>"}
-   h+="<div class='actions'><button class='pri' "+(can?'':'disabled')+" title='"+esc(why)+"' onclick='startTool(\""+esc(t.id)+"\")'>Start</button>";
-   if(t.last)h+="<span class='hint'>last: "+esc(t.last.result?t.last.result.result:'?')+" "+esc(fmtTs(t.last.ts))+"</span>";
-   h+="</div></div>"});
+   h+="<div class='actions'><button class='pri' id='tbtn-"+d+"' onclick='startTool(\""+d+"\")'>Start</button>";
+   h+="<span class='hint' id='tlast-"+d+"'></span></div></div>"});
  h+="</div>"});
- $('tools').innerHTML=h}
-function startTool(id){var t=null;bench.tools.forEach(function(x){if(x.id===id)t=x});if(!t)return;var args={};
+ $('tools').innerHTML=h;benchEls={};
+ bench.tools.forEach(function(t){benchEls[t.id]={btn:$('tbtn-'+t.id),last:$('tlast-'+t.id)}})}
+function updateBench(){if(!benchEls)return;var busy=isBusy();
+ bench.tools.forEach(function(t){var e=benchEls[t.id];if(!e)return;
+  var can=t.ported&&t.installed&&!busy;
+  setDis(e.btn,!can);
+  setProp(e.btn,'title',!t.ported?'not yet ported to the bench page':(!t.installed?'script not installed on this image':(busy?'a run is in progress':'')));
+  setHtml(e.last,t.last?("last: "+esc(t.last.result?t.last.result.result:'?')+" "+esc(fmtTs(t.last.ts))):'')})}
+function startTool(id){if(isBusy())return;var t=null;bench.tools.forEach(function(x){if(x.id===id)t=x});if(!t)return;var args={};
 (t.args||[]).forEach(function(a){var e=$('arg-'+id+'-'+a.name);if(e)args[a.name]=e.value});
 var body={tool:id,args:args};if(t.safety==='live'){if(!confirmLive())return;body.ack_live=true}
- api('POST','/bench/start',body,function(s,d){setMsg('benchmsg',d.message||d.error,s!==200);if(s===200)benchNeedsRefresh=true})}
+ pending=nowMs();pendingId=null;updateBench();updateGroups();
+ setMsg('benchmsg','starting '+id+'...');
+ api('POST','/bench/start',body,function(s,d){
+  if(s!==200){pending=0;updateBench();updateGroups()}
+  setMsg('benchmsg',d.message||d.error,s!==200);if(s===200)benchNeedsRefresh=true;kick()})}
 setIgnoreReq(ignoreReq);
 poll();
 </script></body></html>
@@ -9,7 +9,10 @@ page. Read-only calls need the origin checks only.

 Routes
  GET  /                    the page
-  GET  /state               campaign + per-test state + running run
+  GET  /state               campaign + per-test state + running run.
+                            Carries an ETag; If-None-Match on an
+                            unchanged state gets a 304, which is what an
+                            idle page polls for.
  GET  /catalog             test definitions (title, steps, covers...)
  GET  /bench               bench tool listing
  GET  /result?test&ts      one full result record (log, evidence)
@@ -23,6 +26,7 @@ Routes
  POST /reset {reason}
  POST /export              build + save the artifact, returns it
 """
+import hashlib
 import hmac
 import json
 import os
@@ -96,6 +100,11 @@ class App:

 class Handler(BaseHTTPRequestHandler):
    server_version = "forgetest"
+    # Keep-alive: the page polls, so a handshake and a fresh thread per
+    # request is pure overhead. Idle connections are dropped after the
+    # timeout rather than holding a thread forever.
+    protocol_version = "HTTP/1.1"
+    timeout = 30
    app = None  # set on the server class

    # -- plumbing ---------------------------------------------------------
@@ -108,6 +117,7 @@ class Handler(BaseHTTPRequestHandler):
            body = json.dumps(body, sort_keys=True).encode("utf-8")
        elif isinstance(body, str):
            body = body.encode("utf-8")
+        self.responded = True
        self.send_response(status)
        self.send_header("Content-Type", ctype + ("; charset=utf-8" if ctype.startswith("text/") else ""))
        self.send_header("Content-Length", str(len(body)))
@@ -119,8 +129,25 @@ class Handler(BaseHTTPRequestHandler):
        if self.command != "HEAD":
            self.wfile.write(body)

+    def _send_304(self, etag):
+        self.responded = True
+        self.send_response(304)
+        self.send_header("ETag", etag)
+        self.send_header("Cache-Control", "no-store")
+        self.send_header("Content-Length", "0")
+        self.end_headers()
+
    def _deny(self, status, msg):
-        self._send(status, {"error": msg})
+        # One response per request: on a kept-alive connection a second
+        # one would desynchronize the stream.
+        if getattr(self, "responded", False):
+            return
+        # A refused POST still has its body in the socket. Leaving it
+        # there would make the next read on this connection take the
+        # body for a request line, so the connection ends here.
+        # send_header sets close_connection from this.
+        extra = None if getattr(self, "body_read", True) else {"Connection": "close"}
+        self._send(status, {"error": msg}, extra=extra)

    def _read_ok(self):
        if not origin_ok(self.headers):
@@ -141,10 +168,12 @@ class Handler(BaseHTTPRequestHandler):
    def _body_json(self):
        n = int(self.headers.get("Content-Length") or 0)
        if n <= 0:
+            self.body_read = True
            return {}
        if n > 1 << 20:
            raise ValueError("body too large")
        raw = self.rfile.read(n)
+        self.body_read = True
        ctype = self.headers.get("Content-Type", "")
        if "json" in ctype:
            data = json.loads(raw.decode("utf-8"))
@@ -161,14 +190,22 @@ class Handler(BaseHTTPRequestHandler):
        path = url.path
        query = urllib.parse.parse_qs(url.query)
        r = self.app.runner
+        self.responded = False
        if not self._read_ok():
            return
        try:
            if path == "/":
                self._send(200, _page.render(self.app.token), "text/html")
            elif path == "/state":
+                # Conditional: an idle page polls an unchanged state, and
+                # a 304 spares both ends the payload and the re-render.
                state, _ = r.state()
-                self._send(200, state)
+                body = json.dumps(state, sort_keys=True).encode("utf-8")
+                etag = '"%s"' % hashlib.sha256(body).hexdigest()[:32]
+                if self.headers.get("If-None-Match") == etag:
+                    self._send_304(etag)
+                else:
+                    self._send(200, body, extra={"ETag": etag})
            elif path == "/catalog":
                self._send(200, {"tests": [t.describe() for t in r.tests()],
                                 "catalog_hash": r.catalog_hash})
@@ -210,6 +247,8 @@ class Handler(BaseHTTPRequestHandler):
        path = url.path
        query = urllib.parse.parse_qs(url.query)
        r = self.app.runner
+        self.responded = False
+        self.body_read = False
        if not self._write_ok(query):
            return
        try:
@@ -0,0 +1,199 @@
+"""What keeps the page answering the operator instead of the timer.
+
+Two things went wrong on the bench and are pinned here:
+
+  - the state cost. Every poll re-read and re-parsed the whole result log,
+    and recomputed every test's domain fingerprint. A result record carries
+    its run log, so the file reaches megabytes over a campaign and the poll
+    grew with it. Both are now parsed and computed once.
+  - the wasted payload. An idle page polls an unchanged state; it now gets
+    a 304 instead of the whole thing.
+
+The click-swallowing defect these were found with lives in the page's
+JavaScript and is not reachable from here: rows, prompt buttons and tool
+entries are built once and afterwards only updated in place, because a
+poll that rebuilt them removed the button between the operator's mousedown
+and mouseup, and no click event was ever raised. `test_page_never_rebuilds`
+holds the shape of that rule.
+"""
+import json
+import os
+import shutil
+import tempfile
+import unittest
+
+import helpers
+from forgetest import catalog, manifest as manifest_mod, page
+from forgetest.log import Log
+
+
+def t_noop(ctx):
+    pass
+
+
+class LogCacheTests(unittest.TestCase):
+    """The log is append-only, so a read parses each line exactly once."""
+
+    def setUp(self):
+        self.tmp = tempfile.mkdtemp(prefix="forgetest-log-")
+        self.path = os.path.join(self.tmp, "results.jsonl")
+        self.log = Log(self.path)
+
+    def tearDown(self):
+        shutil.rmtree(self.tmp, ignore_errors=True)
+
+    def write(self, *lines):
+        with open(self.path, "a", encoding="utf-8") as f:
+            for line in lines:
+                f.write(line + "\n")
+
+    def test_missing_file_reads_empty(self):
+        self.assertEqual(self.log.read(), [])
+
+    def test_appends_are_picked_up(self):
+        self.log.append({"t": "campaign", "id": "c1"})
+        self.assertEqual([r["id"] for r in self.log.read()], ["c1"])
+        self.log.append({"t": "result", "test": "a.b"})
+        self.log.append({"t": "result", "test": "c.d"})
+        recs = self.log.read()
+        self.assertEqual([r["t"] for r in recs], ["campaign", "result", "result"])
+        self.assertEqual(recs[2]["test"], "c.d")
+
+    def test_only_new_bytes_are_parsed(self):
+        for i in range(5):
+            self.log.append({"t": "result", "test": "t%d" % i})
+        self.log.read()
+        # a second read must not touch the file at all
+        real_open = open
+        opened = []
+
+        def counting_open(*a, **kw):
+            opened.append(a[0])
+            return real_open(*a, **kw)
+
+        import builtins
+        builtins.open = counting_open
+        try:
+            recs = self.log.read()
+        finally:
+            builtins.open = real_open
+        self.assertEqual(opened, [], "an unchanged log was re-opened")
+        self.assertEqual(len(recs), 5)
+
+    def test_read_returns_a_fresh_list(self):
+        """Callers filter and sort the result; the cache must not be theirs."""
+        self.log.append({"t": "result", "test": "a.b"})
+        first = self.log.read()
+        first.append({"t": "bogus"})
+        self.assertEqual(len(self.log.read()), 1)
+
+    def test_partial_trailing_line_is_held_not_counted_corrupt(self):
+        self.write('{"t":"result","test":"a.b"}')
+        with open(self.path, "a", encoding="utf-8") as f:
+            f.write('{"t":"result","te')       # a line still being written
+        recs = self.log.read()
+        self.assertEqual(len(recs), 1)
+        self.assertEqual(self.log.corrupt, 0)
+        with open(self.path, "a", encoding="utf-8") as f:
+            f.write('st":"c.d"}\n')            # ... now finished
+        recs = self.log.read()
+        self.assertEqual([r["test"] for r in recs], ["a.b", "c.d"])
+        self.assertEqual(self.log.corrupt, 0)
+
+    def test_corrupt_lines_counted_once_not_per_read(self):
+        self.write('{"t":"result","test":"a.b"}', "not json at all", '["not","a","record"]',
+                   '{"t":"result","test":"c.d"}')
+        recs = self.log.read()
+        self.assertEqual([r["test"] for r in recs], ["a.b", "c.d"])
+        self.assertEqual(self.log.corrupt, 2)
+        self.log.read()
+        self.log.read()
+        self.assertEqual(self.log.corrupt, 2, "corrupt lines re-counted on every read")
+
+    def test_replaced_file_is_read_again(self):
+        self.write('{"t":"result","test":"a.b"}', '{"t":"result","test":"c.d"}')
+        self.assertEqual(len(self.log.read()), 2)
+        with open(self.path, "w", encoding="utf-8") as f:
+            f.write('{"t":"campaign","id":"c9"}\n')
+        recs = self.log.read()
+        self.assertEqual([r.get("id") for r in recs], ["c9"])
+
+    def test_blank_lines_are_not_corrupt(self):
+        self.write('{"t":"result","test":"a.b"}', "", "   ", '{"t":"result","test":"c.d"}')
+        self.assertEqual(len(self.log.read()), 2)
+        self.assertEqual(self.log.corrupt, 0)
+
+
+class FingerprintCacheTests(unittest.TestCase):
+    """Memoized per manifest: the page recomputes every test's fingerprint
+    on every poll, and a manifest never changes under a running tool."""
+
+    def setUp(self):
+        self.man = helpers.make_manifest()
+        self.t = helpers.make_test("fake.fp", [("forgectrl", "src/ui.c")], fn=t_noop)
+
+    def test_repeat_calls_agree(self):
+        first = self.t.fingerprint(self.man)
+        self.assertEqual(self.t.fingerprint(self.man), first)
+        self.assertEqual(self.t.fingerprint(self.man), first)
+
+    def test_a_changed_manifest_is_not_served_from_the_cache(self):
+        first = self.t.fingerprint(self.man)
+        man2 = helpers.with_file(self.man, "forgectrl", "src/ui.c", "ui v2")
+        self.assertNotEqual(self.t.fingerprint(man2), first)
+        # and back again: the cache must not have latched the new one either
+        self.assertEqual(self.t.fingerprint(self.man), first)
+
+    def test_a_file_outside_the_coverage_does_not_move_it(self):
+        first = self.t.fingerprint(self.man)
+        man2 = helpers.with_file(self.man, "forgectrl", "src/cool.c", "cool v2")
+        self.assertEqual(self.t.fingerprint(man2), first)
+
+    def test_manifest_without_a_content_hash_is_not_cached(self):
+        """The cache is keyed by the manifest's content hash. A manifest
+        that has none must still fingerprint correctly, not collide."""
+        a = manifest_mod.Manifest({"components": {"forgectrl": {"files": [["src/ui.c", "aaa"]]}},
+                                   "platform": {}})
+        b = manifest_mod.Manifest({"components": {"forgectrl": {"files": [["src/ui.c", "bbb"]]}},
+                                   "platform": {}})
+        self.assertIsNone(a.content_sha)
+        self.assertNotEqual(self.t.fingerprint(a), self.t.fingerprint(b))
+
+    def test_component_file_list_is_stable_and_read_only(self):
+        files = self.man.files("forgectrl")
+        self.assertEqual(files, self.man.files("forgectrl"))
+        self.assertIsNone(self.man.files("no-such-component"))
+
+
+class PageTests(unittest.TestCase):
+    def test_page_never_rebuilds_what_the_operator_may_be_pressing(self):
+        """A poll must update rows, prompt buttons and tool entries in
+        place. Assigning innerHTML to their containers on every poll is
+        what swallowed the clicks; only the one-time build may do it."""
+        html = page.render("0" * 32)
+        for container, builder in (("groups", "buildGroups"), ("tools", "buildBench")):
+            self.assertIn("function %s(" % builder, html,
+                          "no one-time builder for #%s" % container)
+            assigns = html.count("$('%s').innerHTML=" % container)
+            self.assertEqual(assigns, 1,
+                             "#%s is assigned innerHTML %d times; it belongs to the "
+                             "builder alone" % (container, assigns))
+        # the per-poll path writes through the guarded setters only
+        self.assertIn("function setHtml(e,h){if(e&&e.__h!==h)", html)
+        self.assertIn("function updateGroups()", html)
+        self.assertIn("function updateBench()", html)
+        # the prompt buttons are rebuilt only when the prompt changes
+        self.assertIn("if(pk!==promptKey)", html)
+
+    def test_page_is_self_contained_ascii(self):
+        html = page.render("0" * 32)
+        self.assertNotIn("__TOKEN__", html)
+        html.encode("ascii")   # no stray typography in an embedded page
+        stray = sorted(set(hex(ord(c)) for c in html if ord(c) < 32 and c != "\n"))
+        self.assertEqual(stray, [], "control characters in the page source")
+        for remote in ("http://", "https://", "//cdn"):
+            self.assertNotIn(remote, html)
+
+
+if __name__ == "__main__":
+    unittest.main()
@@ -97,6 +97,11 @@ class ServerTests(unittest.TestCase):

    # -- helpers ----------------------------------------------------------
    def call(self, method, path, body=None, token=True, headers=None):
+        st, payload, _ = self.call_h(method, path, body, token, headers)
+        return st, payload
+
+    def call_h(self, method, path, body=None, token=True, headers=None):
+        """As call, plus the response headers."""
        url = "http://127.0.0.1:%d%s" % (self.port, path)
        hdrs = {"Host": "127.0.0.1:%d" % self.port}
        if token:
@@ -112,14 +117,15 @@ class ServerTests(unittest.TestCase):
            with urllib.request.urlopen(req, timeout=10) as r:
                raw = r.read()
                st = r.status
-                ct = r.headers.get("Content-Type", "")
+                rh = r.headers
        except urllib.error.HTTPError as e:
            raw = e.read()
            st = e.code
-            ct = e.headers.get("Content-Type", "")
+            rh = e.headers
+        ct = rh.get("Content-Type", "")
        if "json" in ct:
-            return st, json.loads(raw.decode())
-        return st, raw
+            return st, json.loads(raw.decode()), rh
+        return st, raw, rh

    def wait_idle(self, timeout=10):
        deadline = time.time() + timeout
@@ -161,6 +167,66 @@ class ServerTests(unittest.TestCase):
        st, d = self.call("GET", "/nope")
        self.assertEqual(st, 404)

+    def test_01b_state_is_conditional(self):
+        """The page polls; an unchanged state must cost a 304, and the
+        ETag must move as soon as the state does."""
+        st, d, hdrs = self.call_h("GET", "/state")
+        self.assertEqual(st, 200)
+        etag = hdrs.get("ETag")
+        self.assertTrue(etag and etag.startswith('"'), "no ETag on /state")
+        st, _, hdrs2 = self.call_h("GET", "/state", headers={"If-None-Match": etag})
+        self.assertEqual(st, 304)
+        self.assertEqual(hdrs2.get("ETag"), etag)
+        # a stale validator must not be honored
+        st, _, _ = self.call_h("GET", "/state", headers={"If-None-Match": '"stale"'})
+        self.assertEqual(st, 200)
+        # and the validator moves with the state
+        self.call("POST", "/invalidate", {"reason": "etag check"})
+        st, _, hdrs3 = self.call_h("GET", "/state", headers={"If-None-Match": etag})
+        self.assertEqual(st, 200)
+        self.assertNotEqual(hdrs3.get("ETag"), etag)
+
+    def test_01c_connection_is_kept_alive(self):
+        """A poll per second over a fresh TCP connection each time is
+        waste the board does not need to pay."""
+        import http.client
+        c = http.client.HTTPConnection("127.0.0.1", self.port, timeout=10)
+        try:
+            for _ in range(3):
+                c.request("GET", "/state", headers={"Host": "127.0.0.1:%d" % self.port})
+                r = c.getresponse()
+                r.read()
+                self.assertEqual(r.status, 200)
+                self.assertEqual(r.version, 11)
+                self.assertNotEqual((r.getheader("Connection") or "").lower(), "close")
+                self.assertIsNotNone(r.getheader("Content-Length"))
+        finally:
+            c.close()
+
+    def test_01d_refused_post_does_not_poison_the_connection(self):
+        """A POST refused before its body is read leaves that body in the
+        socket. On a kept-alive connection the next read would take it for
+        a request line, so a refusal must end the connection instead."""
+        import http.client
+        c = http.client.HTTPConnection("127.0.0.1", self.port, timeout=10)
+        try:
+            body = json.dumps({"test": "fake.pass"}).encode()
+            c.request("POST", "/start", body=body,
+                      headers={"Host": "127.0.0.1:%d" % self.port,
+                               "Content-Type": "application/json"})   # no token
+            r = c.getresponse()
+            payload = json.loads(r.read().decode())
+            self.assertEqual(r.status, 403)
+            self.assertEqual(payload["error"], "authentication required")
+            self.assertEqual((r.getheader("Connection") or "").lower(), "close",
+                             "an unread body was left on a connection kept alive")
+        finally:
+            c.close()
+        # the server is still healthy, and the body was never taken for a request
+        st, d = self.call("GET", "/state")
+        self.assertEqual(st, 200)
+        self.assertIsNone(d["running"])
+
    def test_02_run_pass_opens_campaign(self):
        st, d = self.call("GET", "/state")
        self.assertIsNone(d["campaign"])