feat(content): spinner, batch commits, pre-compiled templates, timing

Spinner:
- article_results.html: replace hidden polling div with a visible
  animated spinner banner; CSS spin keyframe added to input.css

Batch commits:
- generate_articles() now commits every 200 articles instead of
  holding one giant transaction; articles appear in the admin UI
  progressively without waiting for the full run

Performance (pre-compiled Jinja templates):
- Create one Environment + compile url/title/meta/body templates once
  before the loop instead of calling _render_pattern() per iteration;
  eliminates ~4 × N Environment() constructions and re-parses of the
  same template strings (N = articles, typically 500+)
- Reuse url_tmpl for hreflang alt-lang rendering

Scenario override passthrough:
- Pass just-computed scenario data directly to bake_scenario_cards()
  via scenario_overrides, avoiding a DB SELECT that reads an uncommitted
  row from a potentially separate connection

Timing instrumentation:
- Accumulate time spent in calc / render / bake phases per run
- Log totals at completion: "done — 500 total | calc=1.2s render=4.3s bake=0.1s"

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

web/src/padelnomics/admin/templates/admin/partials/article_results.html

@@ -1,9 +1,15 @@
 {% if is_generating %}
-<div hx-get="{{ url_for('admin.article_results') }}"
+<div class="generating-banner"
+     hx-get="{{ url_for('admin.article_results') }}"
      hx-trigger="every 3s"
      hx-target="#article-results"
-     hx-swap="innerHTML"
-     style="display:none" aria-hidden="true"></div>
+     hx-swap="innerHTML">
+  <svg class="spinner-icon" width="16" height="16" viewBox="0 0 24 24" fill="none">
+    <circle cx="12" cy="12" r="10" stroke="#CBD5E1" stroke-width="3"/>
+    <path d="M12 2a10 10 0 0 1 10 10" stroke="#0EA5E9" stroke-width="3" stroke-linecap="round"/>
+  </svg>
+  <span>Generating articles…</span>
+</div>
 {% endif %}
 {% if articles %}
 <div class="card">

web/src/padelnomics/content/__init__.py

@@ -8,6 +8,7 @@ are stored in SQLite (routing / application state).
 import json
 import logging
 import re
+import time
 from datetime import UTC, date, datetime, timedelta
 from pathlib import Path
 
@@ -16,7 +17,7 @@ import yaml
 from jinja2 import ChainableUndefined, Environment
 
 from ..analytics import fetch_analytics
-from ..core import execute, fetch_one, slugify, transaction, utcnow_iso
+from ..core import slugify, transaction, utcnow_iso
 
 logger = logging.getLogger(__name__)
 
@@ -301,29 +302,48 @@ async def generate_articles(
     if not rows:
         return 0
 
+    # Pre-compile all Jinja templates once — avoids creating a new Environment()
+    # and re-parsing the same template strings on every iteration.
+    _env = Environment(undefined=ChainableUndefined)
+    _env.filters["slugify"] = slugify
+    _env.filters["datetimeformat"] = _datetimeformat
+    url_tmpl   = _env.from_string(config["url_pattern"])
+    title_tmpl = _env.from_string(config["title_pattern"])
+    meta_tmpl  = _env.from_string(config["meta_description_pattern"])
+    body_tmpl  = _env.from_string(config["body_template"])
+
     publish_date = start_date
     published_today = 0
     generated = 0
     now_iso = utcnow_iso()
 
+    # Timing accumulators — logged at end so we can see where time goes.
+    t_calc = t_render = t_bake = 0.0
+
+    _BATCH_SIZE = 200
+
     async with transaction() as db:
         for row in rows:
             for lang in config["languages"]:
-                # Build render context: row data + language
-                ctx = {**row, "language": lang}
+                # Build render context, replacing None with 0 so numeric
+                # Jinja filters (round, int) don't crash.
+                safe_ctx = {k: (v if v is not None else 0) for k, v in row.items()}
+                safe_ctx["language"] = lang
 
                 # Render URL pattern (no lang prefix — blueprint provides /<lang>)
-                url_path = _render_pattern(config["url_pattern"], ctx)
+                url_path = url_tmpl.render(**safe_ctx)
                 if is_reserved_path(url_path):
                     continue
 
-                title = _render_pattern(config["title_pattern"], ctx)
-                meta_desc = _render_pattern(config["meta_description_pattern"], ctx)
+                title     = title_tmpl.render(**safe_ctx)
+                meta_desc = meta_tmpl.render(**safe_ctx)
                 article_slug = slug + "-" + lang + "-" + str(row[config["natural_key"]])
 
                 # Calculator content type: create scenario
                 scenario_slug = None
+                scenario_overrides = None
                 if config["content_type"] == "calculator":
+                    t0 = time.perf_counter()
                     # DuckDB lowercases all column names; build a case-insensitive
                     # reverse map so "ratepeak" (stored) matches "ratePeak" (DEFAULTS).
                     _defaults_ci = {k.lower(): k for k in DEFAULTS}
@@ -334,6 +354,7 @@ async def generate_articles(
                     }
                     state = validate_state(calc_overrides)
                     d = calc(state, lang=lang)
+                    t_calc += time.perf_counter() - t0
 
                     scenario_slug = slug + "-" + str(row[config["natural_key"]])
                     dbl = state.get("dblCourts", 0)
@@ -360,12 +381,36 @@ async def generate_articles(
                         ),
                     )
 
-                    ctx["scenario_slug"] = scenario_slug
+                    safe_ctx["scenario_slug"] = scenario_slug
+                    # Pass scenario data directly so bake_scenario_cards skips the
+                    # DB re-fetch (the row was just upserted and may not be visible
+                    # on a separate connection within the same uncommitted transaction).
+                    scenario_overrides = {
+                        scenario_slug: {
+                            "slug": scenario_slug,
+                            "title": city,
+                            "location": city,
+                            "country": country,
+                            "venue_type": state.get("venue", "indoor"),
+                            "ownership": state.get("own", "rent"),
+                            "court_config": court_config,
+                            "state_json": json.dumps(state),
+                            "calc_json": json.dumps(d),
+                            "created_at": now_iso,
+                        }
+                    }
 
                 # Render body template
-                body_md = _render_pattern(config["body_template"], ctx)
+                t0 = time.perf_counter()
+                body_md   = body_tmpl.render(**safe_ctx)
                 body_html = mistune.html(body_md)
-                body_html = await bake_scenario_cards(body_html, lang=lang)
+                t_render += time.perf_counter() - t0
+
+                t0 = time.perf_counter()
+                body_html = await bake_scenario_cards(
+                    body_html, lang=lang, scenario_overrides=scenario_overrides
+                )
+                t_bake += time.perf_counter() - t0
 
                 # Extract FAQ pairs for structured data
                 faq_pairs = _extract_faq_pairs(body_md)
@@ -377,16 +422,16 @@ async def generate_articles(
                     8, 0, 0,
                 ).isoformat()
 
-                # Hreflang links
+                # Hreflang links — reuse compiled url_tmpl with swapped language
                 hreflang_links = []
                 for alt_lang in config["languages"]:
-                    alt_url = f"/{alt_lang}" + _render_pattern(config["url_pattern"], {**row, "language": alt_lang})
+                    alt_url = f"/{alt_lang}" + url_tmpl.render(**{**safe_ctx, "language": alt_lang})
                     hreflang_links.append(
                         f'<link rel="alternate" hreflang="{alt_lang}" href="{base_url}{alt_url}" />'
                     )
                 # x-default points to English (or first language)
                 default_lang = "en" if "en" in config["languages"] else config["languages"][0]
-                default_url = f"/{default_lang}" + _render_pattern(config["url_pattern"], {**row, "language": default_lang})
+                default_url = f"/{default_lang}" + url_tmpl.render(**{**safe_ctx, "language": default_lang})
                 hreflang_links.append(
                     f'<link rel="alternate" hreflang="x-default" href="{base_url}{default_url}" />'
                 )
@@ -451,7 +496,13 @@ async def generate_articles(
                 )
 
                 generated += 1
-                if generated % 25 == 0:
+
+                # Commit every _BATCH_SIZE articles so the admin UI shows progress
+                # earlier rather than waiting for the full run to complete.
+                if generated % _BATCH_SIZE == 0:
+                    await db.commit()
+                    logger.info("%s: committed batch — %d articles", slug, generated)
+                elif generated % 25 == 0:
                     logger.info("%s: %d articles written…", slug, generated)
 
                 # Stagger dates
@@ -460,7 +511,10 @@ async def generate_articles(
                     published_today = 0
                     publish_date += timedelta(days=1)
 
-    logger.info("%s: done — %d total", slug, generated)
+    logger.info(
+        "%s: done — %d total | calc=%.1fs render=%.1fs bake=%.1fs",
+        slug, generated, t_calc, t_render, t_bake,
+    )
     return generated
 
 

web/src/padelnomics/static/css/input.css

@@ -568,4 +568,19 @@
   .article-body details > div {
     @apply px-4 pb-4 text-slate-dark;
   }
+
+  /* Article generation spinner banner */
+  .generating-banner {
+    @apply flex items-center gap-3 rounded-xl border border-light-gray bg-white text-sm text-slate-dark mb-4;
+    padding: 0.75rem 1rem;
+  }
+  .spinner-icon {
+    flex-shrink: 0;
+    animation: spin-icon 0.9s linear infinite;
+  }
+}
+
+@keyframes spin-icon {
+  from { transform: rotate(0deg); }
+  to   { transform: rotate(360deg); }
 }