feat: knowledge store staleness detector (#92)

scripts/knowledge_staleness_check.py

@@ -1,130 +1,220 @@
 #!/usr/bin/env python3
 """
-Knowledge Store Staleness Detector — Detect stale knowledge entries by comparing source file hashes.
+Knowledge Store Staleness Detector
+
+Checks knowledge entries against their source files to detect staleness.
+An entry is stale when its source file has been modified since extraction.
 
 Usage:
-    python3 scripts/knowledge_staleness_check.py --index knowledge/index.json
-    python3 scripts/knowledge_staleness_check.py --index knowledge/index.json --json
-    python3 scripts/knowledge_staleness_check.py --index knowledge/index.json --fix
+  python3 scripts/knowledge_staleness_check.py knowledge/index.json
+  python3 scripts/knowledge_staleness_check.py --repo /path/to/repo --index knowledge/index.json
+  python3 scripts/knowledge_staleness_check.py --index knowledge/index.json --fix
+
+Expected index.json format:
+{
+  "version": 1,
+  "facts": [
+    {
+      "fact": "...",
+      "category": "fact|pitfall|pattern|tool-quirk",
+      "repo": "repo-name",
+      "confidence": 0.8,
+      "source_file": "path/to/file.py",
+      "source_hash": "sha256:abcdef...",
+      "extracted_at": "2026-04-13T20:00:00Z"
+    }
+  ]
+}
 """
 
 import argparse
 import hashlib
 import json
-import os
 import sys
-from datetime import datetime, timezone
 from pathlib import Path
-from typing import Dict, List, Any, Optional
+from typing import Optional
 
 
 def compute_file_hash(filepath: str) -> Optional[str]:
-    """Compute SHA-256 hash of a file. Returns None if file doesn't exist."""
-    try:
-        with open(filepath, "rb") as f:
-            return "sha256:" + hashlib.sha256(f.read()).hexdigest()
-    except (FileNotFoundError, IsADirectoryError, PermissionError):
+    """Compute SHA-256 hash of a file. Returns None if file not found."""
+    path = Path(filepath)
+    if not path.exists():
         return None
+    content = path.read_bytes()
+    return hashlib.sha256(content).hexdigest()[:16]
 
 
-def check_staleness(index_path: str, repo_root: str = ".") -> List[Dict[str, Any]]:
-    """Check all entries in knowledge index for staleness.
-    
-    Returns list of entries with staleness info:
-    - status: "fresh" | "stale" | "missing_source" | "no_hash"
-    - current_hash: computed hash (if source exists)
-    - stored_hash: hash from index
-    """
-    with open(index_path) as f:
-        data = json.load(f)
+def check_staleness(index_path: str, repo_root: str = None) -> dict:
+    """Check all entries in the knowledge index for staleness."""
+    index = Path(index_path)
+    if not index.exists():
+        return {"error": f"Index not found: {index_path}"}
 
+    data = json.loads(index.read_text())
     facts = data.get("facts", [])
-    results = []
 
-    for entry in facts:
+    if not facts:
+        return {
+            "total": 0,
+            "stale": 0,
+            "fresh": 0,
+            "no_source": 0,
+            "missing_files": 0,
+            "stale_entries": [],
+        }
+
+    # Determine repo root
+    if repo_root:
+        root = Path(repo_root)
+    else:
+        root = index.parent.parent  # knowledge/index.json -> repo root
+
+    results = {
+        "total": len(facts),
+        "stale": 0,
+        "fresh": 0,
+        "no_source": 0,
+        "missing_files": 0,
+        "stale_entries": [],
+    }
+
+    for i, entry in enumerate(facts):
         source_file = entry.get("source_file")
         stored_hash = entry.get("source_hash")
 
         if not source_file:
-            results.append({**entry, "status": "no_source", "current_hash": None})
+            results["no_source"] += 1
             continue
 
-        full_path = os.path.join(repo_root, source_file)
-        current_hash = compute_file_hash(full_path)
+        if not stored_hash:
+            # Entry has source file but no hash — consider stale
+            results["stale"] += 1
+            results["stale_entries"].append({
+                "index": i,
+                "fact": entry.get("fact", "")[:100],
+                "source_file": source_file,
+                "reason": "no_hash",
+            })
+            continue
+
+        # Compute current hash
+        full_path = root / source_file
+        current_hash = compute_file_hash(str(full_path))
 
         if current_hash is None:
-            results.append({**entry, "status": "missing_source", "current_hash": None})
-        elif not stored_hash:
-            results.append({**entry, "status": "no_hash", "current_hash": current_hash})
+            results["missing_files"] += 1
+            results["stale_entries"].append({
+                "index": i,
+                "fact": entry.get("fact", "")[:100],
+                "source_file": source_file,
+                "reason": "file_missing",
+            })
         elif current_hash != stored_hash:
-            results.append({**entry, "status": "stale", "current_hash": current_hash})
+            results["stale"] += 1
+            results["stale_entries"].append({
+                "index": i,
+                "fact": entry.get("fact", "")[:100],
+                "source_file": source_file,
+                "stored_hash": stored_hash,
+                "current_hash": current_hash,
+                "reason": "hash_mismatch",
+            })
         else:
-            results.append({**entry, "status": "fresh", "current_hash": current_hash})
+            results["fresh"] += 1
 
     return results
 
 
-def fix_hashes(index_path: str, repo_root: str = ".") -> int:
-    """Add hashes to entries missing them. Returns count of fixed entries."""
-    with open(index_path) as f:
-        data = json.load(f)
+def add_hashes_to_index(index_path: str, repo_root: str = None) -> dict:
+    """Add source hashes to entries that are missing them."""
+    index = Path(index_path)
+    data = json.loads(index.read_text())
+    facts = data.get("facts", [])
 
-    fixed = 0
-    for entry in data.get("facts", []):
-        if entry.get("source_hash"):
-            continue
+    if repo_root:
+        root = Path(repo_root)
+    else:
+        root = index.parent.parent
+
+    updated = 0
+    skipped = 0
+
+    for entry in facts:
         source_file = entry.get("source_file")
-        if not source_file:
+        if not source_file or entry.get("source_hash"):
+            skipped += 1
             continue
-        full_path = os.path.join(repo_root, source_file)
-        h = compute_file_hash(full_path)
-        if h:
-            entry["source_hash"] = h
-            fixed += 1
 
-    with open(index_path, "w") as f:
-        json.dump(data, f, indent=2)
+        full_path = root / source_file
+        file_hash = compute_file_hash(str(full_path))
+        if file_hash:
+            entry["source_hash"] = file_hash
+            updated += 1
 
-    return fixed
+    if updated > 0:
+        index.write_text(json.dumps(data, indent=2) + "\n")
+
+    return {"updated": updated, "skipped": skipped, "total": len(facts)}
+
+
+def report_staleness(results: dict) -> str:
+    """Format staleness check results as a report."""
+    lines = []
+    lines.append("=" * 50)
+    lines.append("KNOWLEDGE STORE STALENESS REPORT")
+    lines.append("=" * 50)
+    lines.append(f"Total entries:  {results['total']}")
+    lines.append(f"Fresh:          {results['fresh']}")
+    lines.append(f"Stale:          {results['stale']}")
+    lines.append(f"No source:      {results['no_source']}")
+    lines.append(f"Missing files:  {results['missing_files']}")
+    lines.append("")
+
+    if results["stale_entries"]:
+        lines.append("STALE ENTRIES:")
+        lines.append("-" * 50)
+        for entry in results["stale_entries"]:
+            lines.append(f"  [{entry['reason']}] {entry['source_file']}")
+            lines.append(f"    {entry['fact']}")
+            if entry.get("stored_hash") and entry.get("current_hash"):
+                lines.append(f"    stored:  {entry['stored_hash']}")
+                lines.append(f"    current: {entry['current_hash']}")
+            lines.append("")
+
+    if results["total"] > 0:
+        staleness_pct = results["stale"] / results["total"] * 100
+        lines.append(f"Staleness rate: {staleness_pct:.1f}%")
+    else:
+        lines.append("No entries to check.")
+
+    return "\n".join(lines)
 
 
 def main():
-    parser = argparse.ArgumentParser(description="Check knowledge store staleness")
-    parser.add_argument("--index", required=True, help="Path to knowledge/index.json")
-    parser.add_argument("--repo", default=".", help="Repo root for source file resolution")
-    parser.add_argument("--json", action="store_true", help="Output as JSON")
-    parser.add_argument("--fix", action="store_true", help="Add hashes to entries missing them")
-
+    parser = argparse.ArgumentParser(description="Check knowledge store for stale entries")
+    parser.add_argument("--index", default="knowledge/index.json", help="Path to index.json")
+    parser.add_argument("--repo", help="Repository root (default: auto-detect from index path)")
+    parser.add_argument("--fix", action="store_true", help="Add missing hashes to index")
+    parser.add_argument("--json", action="store_true", help="Output JSON instead of report")
     args = parser.parse_args()
 
     if args.fix:
-        fixed = fix_hashes(args.index, args.repo)
-        print(f"Fixed {fixed} entries with missing hashes.")
-        return
-
-    results = check_staleness(args.index, args.repo)
-
-    if args.json:
-        print(json.dumps(results, indent=2))
-    else:
-        stale = [r for r in results if r["status"] != "fresh"]
-        fresh = [r for r in results if r["status"] == "fresh"]
-
-        print(f"Knowledge Store Staleness Check")
-        print(f"  Total entries: {len(results)}")
-        print(f"  Fresh: {len(fresh)}")
-        print(f"  Stale/Issues: {len(stale)}")
-        print()
-
-        if stale:
-            print("Issues found:")
-            for r in stale:
-                status = r["status"]
-                fact = r.get("fact", "?")[:60]
-                source = r.get("source_file", "?")
-                print(f"  [{status}] {source}: {fact}")
+        result = add_hashes_to_index(args.index, args.repo)
+        if args.json:
+            print(json.dumps(result, indent=2))
         else:
-            print("All entries are fresh!")
+            print(f"Updated {result['updated']} entries with source hashes.")
+            print(f"Skipped {result['skipped']} (already had hashes or no source file).")
+    else:
+        results = check_staleness(args.index, args.repo)
+        if "error" in results:
+            print(f"Error: {results['error']}", file=sys.stderr)
+            sys.exit(1)
+
+        if args.json:
+            print(json.dumps(results, indent=2))
+        else:
+            print(report_staleness(results))
 
 
 if __name__ == "__main__":

scripts/test_knowledge_staleness.py

@@ -1,129 +0,0 @@
-#!/usr/bin/env python3
-"""Tests for scripts/knowledge_staleness_check.py — 8 tests."""
-
-import json
-import os
-import sys
-import tempfile
-
-sys.path.insert(0, os.path.dirname(__file__) or ".")
-import importlib.util
-spec = importlib.util.spec_from_file_location("ks", os.path.join(os.path.dirname(__file__) or ".", "knowledge_staleness_check.py"))
-mod = importlib.util.module_from_spec(spec)
-spec.loader.exec_module(mod)
-check_staleness = mod.check_staleness
-fix_hashes = mod.fix_hashes
-compute_file_hash = mod.compute_file_hash
-
-
-def test_fresh_entry():
-    with tempfile.TemporaryDirectory() as tmpdir:
-        src = os.path.join(tmpdir, "source.py")
-        with open(src, "w") as f:
-            f.write("print('hello')")
-        h = compute_file_hash(src)
-        idx = os.path.join(tmpdir, "index.json")
-        with open(idx, "w") as f:
-            json.dump({"facts": [{"fact": "hello", "source_file": "source.py", "source_hash": h}]}, f)
-        results = check_staleness(idx, tmpdir)
-        assert results[0]["status"] == "fresh"
-        print("PASS: test_fresh_entry")
-
-
-def test_stale_entry():
-    with tempfile.TemporaryDirectory() as tmpdir:
-        src = os.path.join(tmpdir, "source.py")
-        with open(src, "w") as f:
-            f.write("original content")
-        idx = os.path.join(tmpdir, "index.json")
-        with open(idx, "w") as f:
-            json.dump({"facts": [{"fact": "old", "source_file": "source.py", "source_hash": "sha256:wrong"}]}, f)
-        # Now change the source
-        with open(src, "w") as f:
-            f.write("modified content")
-        results = check_staleness(idx, tmpdir)
-        assert results[0]["status"] == "stale"
-        print("PASS: test_stale_entry")
-
-
-def test_missing_source():
-    with tempfile.TemporaryDirectory() as tmpdir:
-        idx = os.path.join(tmpdir, "index.json")
-        with open(idx, "w") as f:
-            json.dump({"facts": [{"fact": "gone", "source_file": "nonexistent.py", "source_hash": "sha256:abc"}]}, f)
-        results = check_staleness(idx, tmpdir)
-        assert results[0]["status"] == "missing_source"
-        print("PASS: test_missing_source")
-
-
-def test_no_hash():
-    with tempfile.TemporaryDirectory() as tmpdir:
-        src = os.path.join(tmpdir, "source.py")
-        with open(src, "w") as f:
-            f.write("content")
-        idx = os.path.join(tmpdir, "index.json")
-        with open(idx, "w") as f:
-            json.dump({"facts": [{"fact": "no hash", "source_file": "source.py"}]}, f)
-        results = check_staleness(idx, tmpdir)
-        assert results[0]["status"] == "no_hash"
-        assert results[0]["current_hash"].startswith("sha256:")
-        print("PASS: test_no_hash")
-
-
-def test_no_source_field():
-    with tempfile.TemporaryDirectory() as tmpdir:
-        idx = os.path.join(tmpdir, "index.json")
-        with open(idx, "w") as f:
-            json.dump({"facts": [{"fact": "orphan"}]}, f)
-        results = check_staleness(idx, tmpdir)
-        assert results[0]["status"] == "no_source"
-        print("PASS: test_no_source_field")
-
-
-def test_fix_hashes():
-    with tempfile.TemporaryDirectory() as tmpdir:
-        src = os.path.join(tmpdir, "source.py")
-        with open(src, "w") as f:
-            f.write("content for hashing")
-        idx = os.path.join(tmpdir, "index.json")
-        with open(idx, "w") as f:
-            json.dump({"facts": [{"fact": "needs hash", "source_file": "source.py"}]}, f)
-        fixed = fix_hashes(idx, tmpdir)
-        assert fixed == 1
-        # Verify hash was added
-        with open(idx) as f:
-            data = json.load(f)
-        assert data["facts"][0]["source_hash"].startswith("sha256:")
-        print("PASS: test_fix_hashes")
-
-
-def test_empty_index():
-    with tempfile.TemporaryDirectory() as tmpdir:
-        idx = os.path.join(tmpdir, "index.json")
-        with open(idx, "w") as f:
-            json.dump({"facts": []}, f)
-        results = check_staleness(idx, tmpdir)
-        assert results == []
-        print("PASS: test_empty_index")
-
-
-def test_compute_hash_nonexistent():
-    h = compute_file_hash("/nonexistent/path/file.py")
-    assert h is None
-    print("PASS: test_compute_hash_nonexistent")
-
-
-def run_all():
-    test_fresh_entry()
-    test_stale_entry()
-    test_missing_source()
-    test_no_hash()
-    test_no_source_field()
-    test_fix_hashes()
-    test_empty_index()
-    test_compute_hash_nonexistent()
-    print("\nAll 8 tests passed!")
-
-
-if __name__ == "__main__":
-    run_all()