(MOT-4295) feat(ci): publish harness integration and e2e coverage to the metrics site

.github/benchmark-site/coverage/index.html

@@ -0,0 +1,148 @@
+<!DOCTYPE html>
+<html lang="en">
+  <head>
+    <meta charset="utf-8">
+    <meta name="viewport" content="width=device-width, initial-scale=1">
+    <meta
+      name="description"
+      content="LLVM line coverage for the harness integration and E2E suites."
+    >
+    <meta name="color-scheme" content="dark light">
+    <title>Harness stack coverage</title>
+    <link rel="stylesheet" href="../styles.css">
+    <style>
+      .coverage-grid {
+        display: grid;
+        grid-template-columns: repeat(auto-fit, minmax(18rem, 1fr));
+        gap: 1.25rem;
+      }
+      .coverage-card {
+        display: flex;
+        flex-direction: column;
+        gap: 0.75rem;
+        padding: 1.5rem;
+      }
+      .coverage-card h2 {
+        margin: 0;
+      }
+      .coverage-percent {
+        font-size: 2.5rem;
+        font-weight: 700;
+        font-variant-numeric: tabular-nums;
+      }
+      .coverage-meta {
+        opacity: 0.75;
+        font-size: 0.875rem;
+      }
+      .coverage-links {
+        display: flex;
+        gap: 0.75rem;
+        flex-wrap: wrap;
+      }
+    </style>
+  </head>
+  <body>
+    <a class="skip-link" href="#main">Skip to coverage reports</a>
+    <div class="ambient ambient-one" aria-hidden="true"></div>
+    <div class="ambient ambient-two" aria-hidden="true"></div>
+
+    <header class="topbar">
+      <a class="brand" href="https://github.com/iii-hq/workers" aria-label="iii workers">
+        <span class="brand-copy">
+          <strong>iii</strong>
+          <span>Harness benchmarks</span>
+        </span>
+      </a>
+      <nav class="topbar-actions" aria-label="Dashboard actions">
+        <a class="button button-secondary" href="../index.html">Executions</a>
+        <a class="button button-secondary" href="../coverage-trend/">Trend</a>
+      </nav>
+    </header>
+
+    <main id="main" class="page-shell overview-shell">
+      <section class="page-heading" aria-labelledby="page-title">
+        <div>
+          <div class="eyebrow">
+            <span class="live-dot" aria-hidden="true"></span>
+            Harness stack
+          </div>
+          <h1 id="page-title">Code coverage</h1>
+          <p>LLVM line coverage of the instrumented stack, refreshed by the daily E2E cycle.</p>
+        </div>
+        <div class="sync-block">
+          <span id="sync-label">Last published</span>
+          <time id="last-update" datetime="">Waiting for data</time>
+        </div>
+      </section>
+
+      <section id="empty-state" class="empty-state" hidden>
+        <div class="empty-icon" aria-hidden="true">⌁</div>
+        <h2>No coverage published yet</h2>
+        <p>The next scheduled Harness E2E Daily workflow will publish the first reports here.</p>
+      </section>
+
+      <section id="coverage-content" class="coverage-grid" hidden>
+        <article class="panel coverage-card" id="card-integration">
+          <h2>Integration suite</h2>
+          <div class="coverage-percent" data-percent>–</div>
+          <div class="coverage-meta" data-meta>Not published yet.</div>
+          <div class="coverage-links">
+            <a class="button button-secondary" href="./integration/index.html" data-report hidden>
+              Browse report
+            </a>
+          </div>
+        </article>
+        <article class="panel coverage-card" id="card-e2e">
+          <h2>E2E suite</h2>
+          <div class="coverage-percent" data-percent>–</div>
+          <div class="coverage-meta" data-meta>Not published yet.</div>
+          <div class="coverage-links">
+            <a class="button button-secondary" href="./e2e/index.html" data-report hidden>
+              Browse report
+            </a>
+          </div>
+        </article>
+      </section>
+    </main>
+
+    <script>
+      window.HARNESS_COVERAGE = null;
+    </script>
+    <script src="./summary.js"></script>
+    <script>
+      (function () {
+        var data = window.HARNESS_COVERAGE;
+        var empty = document.getElementById("empty-state");
+        var content = document.getElementById("coverage-content");
+        var suites = data && data.suites ? data.suites : {};
+        var hasAny = Boolean(suites.e2e || suites.integration);
+        if (!hasAny) {
+          empty.hidden = false;
+          return;
+        }
+        content.hidden = false;
+
+        if (data.updated_at) {
+          var time = document.getElementById("last-update");
+          time.dateTime = data.updated_at;
+          time.textContent = new Date(data.updated_at).toLocaleString();
+        }
+
+        function render(cardId, summary) {
+          var card = document.getElementById(cardId);
+          if (!summary || !summary.totals || !summary.totals.lines) return;
+          var lines = summary.totals.lines;
+          card.querySelector("[data-percent]").textContent =
+            lines.percent.toFixed(1) + "%";
+          card.querySelector("[data-meta]").textContent =
+            (lines.covered != null ? lines.covered.toLocaleString() : "?") +
+            " of " + (lines.count != null ? lines.count.toLocaleString() : "?") +
+            " lines covered · " + (summary.generated_at || "");
+          card.querySelector("[data-report]").hidden = false;
+        }
+        render("card-integration", suites.integration);
+        render("card-e2e", suites.e2e);
+      })();
+    </script>
+  </body>
+</html>

.github/benchmark-site/index.html

@@ -25,6 +25,7 @@
       </a>
       <nav class="topbar-actions" aria-label="Dashboard actions">
         <span id="preview-badge" class="badge badge-preview" hidden>Preview data</span>
+        <a class="button button-secondary" href="./coverage/">Coverage</a>
         <a id="actions-link" class="button button-secondary" href="https://github.com/iii-hq/workers/actions">
           View Actions <span aria-hidden="true">↗</span>
         </a>

.github/scripts/coverage_report.sh

@@ -0,0 +1,90 @@
+#!/usr/bin/env bash
+# Merge LLVM coverage profiles from a dedicated profraw directory and emit a
+# combined multi-binary report: html/, summary.json, and report.txt.
+#
+# Usage:
+#   coverage_report.sh --profraw-dir DIR --output-dir DIR --title NAME \
+#     --object BIN [--object BIN ...]
+#
+# Binaries must be built with:
+#   RUSTFLAGS="-Cinstrument-coverage -Cllvm-args=-runtime-counter-relocation"
+# and run with LLVM_PROFILE_FILE containing %c (continuous mode) so profiles
+# survive SIGTERM/SIGKILL teardown. Requires the rustup llvm-tools component.
+set -euo pipefail
+
+IGNORE_REGEX='\.cargo/(registry|git)|/rustc/|harness/tests/'
+
+profraw_dir=""
+output_dir=""
+title="coverage"
+objects=()
+
+while [[ $# -gt 0 ]]; do
+  case "$1" in
+    --profraw-dir) profraw_dir="$2"; shift 2 ;;
+    --output-dir) output_dir="$2"; shift 2 ;;
+    --title) title="$2"; shift 2 ;;
+    --object) objects+=("$2"); shift 2 ;;
+    *) echo "unknown argument: $1" >&2; exit 2 ;;
+  esac
+done
+
+[[ -n "$profraw_dir" && -n "$output_dir" ]] || {
+  echo "usage: $0 --profraw-dir DIR --output-dir DIR --title NAME --object BIN [--object BIN ...]" >&2
+  exit 2
+}
+
+tool_dir="$(dirname "$(rustc --print target-libdir)")/bin"
+for tool in llvm-profdata llvm-cov; do
+  [[ -x "$tool_dir/$tool" ]] || {
+    echo "missing $tool_dir/$tool; install with: rustup component add llvm-tools" >&2
+    exit 2
+  }
+done
+
+mkdir -p "$output_dir"
+
+mapfile -t profraws < <(find "$profraw_dir" -name '*.profraw' -type f 2>/dev/null | sort)
+if [[ ${#profraws[@]} -eq 0 ]]; then
+  echo "no .profraw files under $profraw_dir; skipping report" >&2
+  exit 0
+fi
+
+object_args=()
+for object in "${objects[@]}"; do
+  if [[ -x "$object" ]]; then
+    object_args+=(-object "$object")
+  else
+    echo "warning: skipping missing object $object" >&2
+  fi
+done
+[[ ${#object_args[@]} -gt 0 ]] || { echo "no usable --object binaries" >&2; exit 2; }
+
+demangler_args=()
+if command -v rustfilt >/dev/null 2>&1; then
+  demangler_args=(-Xdemangler=rustfilt)
+fi
+
+"$tool_dir/llvm-profdata" merge -sparse "${profraws[@]}" -o "$output_dir/merged.profdata"
+
+"$tool_dir/llvm-cov" show --format=html --output-dir="$output_dir/html" \
+  -instr-profile="$output_dir/merged.profdata" \
+  --ignore-filename-regex="$IGNORE_REGEX" \
+  "${demangler_args[@]}" \
+  "${object_args[@]}"
+
+"$tool_dir/llvm-cov" report \
+  -instr-profile="$output_dir/merged.profdata" \
+  --ignore-filename-regex="$IGNORE_REGEX" \
+  "${object_args[@]}" > "$output_dir/report.txt"
+
+"$tool_dir/llvm-cov" export -summary-only \
+  -instr-profile="$output_dir/merged.profdata" \
+  --ignore-filename-regex="$IGNORE_REGEX" \
+  "${object_args[@]}" \
+  | jq --arg title "$title" --arg at "$(date -u +%Y-%m-%dT%H:%M:%SZ)" \
+    '{title: $title, generated_at: $at, totals: .data[0].totals}' \
+  > "$output_dir/summary.json"
+
+echo "coverage report written to $output_dir"
+tail -1 "$output_dir/report.txt"