Render source_url as a link in the HTML viewer

graphify/exporters/html.py

@@ -46,6 +46,8 @@ def _html_styles() -> str:
   #info-content { font-size: 13px; color: #ccc; line-height: 1.6; }
   #info-content .field { margin-bottom: 5px; }
   #info-content .field b { color: #e0e0e0; }
+  #info-content .field a.source-link { color: #6fb3ff; text-decoration: none; word-break: break-all; }
+  #info-content .field a.source-link:hover { text-decoration: underline; }
   #info-content .empty { color: #555; font-style: italic; }
   .neighbor-link { display: block; padding: 2px 6px; margin: 2px 0; border-radius: 3px; cursor: pointer; font-size: 12px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; border-left: 3px solid #333; }
   .neighbor-link:hover { background: #2a2a4e; }
@@ -147,12 +149,25 @@ def _html_script(nodes_json: str, edges_json: str, legend_json: str) -> str:
   return String(s).replace(/&/g,'&amp;').replace(/</g,'&lt;').replace(/>/g,'&gt;').replace(/"/g,'&quot;').replace(/'/g,'&#39;');
 }}
 
+// URL allowlist — esc() is enough for text but NOT for an href. source_url is
+// ingested content, and `javascript:alert(1)` contains no HTML metacharacters,
+// so it would survive esc() intact as a live link. Only http(s) is linkified.
+// No base is passed to URL(), so relative values are rejected too and a
+// source_url can never resolve against the viewer's own origin.
+function safeUrl(u) {{
+  if (!u) return '';
+  try {{
+    const parsed = new URL(String(u));
+    return (parsed.protocol === 'http:' || parsed.protocol === 'https:') ? parsed.href : '';
+  }} catch (e) {{ return ''; }}
+}}
+
 // Build vis datasets
 const nodesDS = new vis.DataSet(RAW_NODES.map(n => ({{
   id: n.id, label: n.label, color: n.color, size: n.size,
   font: n.font, title: n.title,
   _community: n.community, _community_name: n.community_name,
-  _source_file: n.source_file, _file_type: n.file_type, _degree: n.degree,
+  _source_file: n.source_file, _source_url: n.source_url, _file_type: n.file_type, _degree: n.degree,
 }})));
 
 const edgesDS = new vis.DataSet(RAW_EDGES.map((e, i) => ({{
@@ -209,6 +224,7 @@ def _html_script(nodes_json: str, edges_json: str, legend_json: str) -> str:
     <div class="field">Type: ${{esc(n._file_type || 'unknown')}}</div>
     <div class="field">Community: ${{esc(n._community_name)}}</div>
     <div class="field">Source: ${{esc(n._source_file || '-')}}</div>
+    ${{safeUrl(n._source_url) ? `<div class="field">Link: <a class="source-link" href="${{esc(safeUrl(n._source_url))}}" target="_blank" rel="noopener noreferrer">${{esc(n._source_url)}}</a></div>` : ''}}
     <div class="field">Degree: ${{n._degree}}</div>
     ${{neighborIds.length ? `<div class="field" style="margin-top:8px;color:#aaa;font-size:11px">Neighbors (${{neighborIds.length}})</div><div id="neighbors-list">${{neighborItems}}</div>` : ''}}
   `;
@@ -523,6 +539,7 @@ def to_html(
             "community": cid,
             "community_name": sanitize_label((community_labels or {}).get(cid, f"Community {cid}")),
             "source_file": sanitize_label(str(data.get("source_file") or "")),
+            "source_url": str(data.get("source_url") or ""),
             "file_type": data.get("file_type", ""),
             "degree": deg,
         }

tests/test_export.py

@@ -1087,3 +1087,48 @@ def test_hyperedge_convex_hull_js_is_geometrically_sound():
         proc = subprocess.run([node, str(js)], capture_output=True, text=True, timeout=60)
     assert proc.returncode == 0, proc.stderr
     assert proc.stdout.strip() == "0", f"geometry violations: {proc.stdout.strip()}"
+
+
+def _html_with_source_url(url):
+    """Render a one-node graph whose node carries the given source_url."""
+    import networkx as nx
+    G = nx.Graph()
+    G.add_node("n1", label="Doc Node", file_type="concept",
+               source_file="notes.md", source_url=url)
+    G.add_node("n2", label="Other", file_type="concept", source_file="other.md")
+    G.add_edge("n1", "n2", relation="references", confidence="EXTRACTED")
+    with tempfile.TemporaryDirectory() as tmp:
+        out = Path(tmp) / "graph.html"
+        to_html(G, {0: ["n1", "n2"]}, str(out))
+        return out.read_text()
+
+
+def test_to_html_emits_source_url_in_node_payload():
+    html = _html_with_source_url("https://example.com/page")
+    assert '"source_url": "https://example.com/page"' in html
+
+
+def test_to_html_omits_source_url_when_absent():
+    """A node without source_url still renders, with an empty payload value."""
+    html = _html_with_source_url("")
+    assert '"source_url": ""' in html
+
+
+def test_to_html_ships_url_scheme_allowlist():
+    """The viewer must gate hrefs on scheme: esc() alone would let
+    javascript: through, since it contains no HTML metacharacters."""
+    html = _html_with_source_url("https://example.com/page")
+    assert "function safeUrl" in html
+    assert "parsed.protocol === 'http:'" in html
+    assert "parsed.protocol === 'https:'" in html
+    # the anchor is built through safeUrl, never from the raw value
+    assert 'href="${esc(safeUrl(n._source_url))}"' in html
+    assert 'rel="noopener noreferrer"' in html
+
+
+def test_to_html_does_not_emit_raw_javascript_href():
+    """A hostile source_url reaches the payload as data, but must never be
+    written into the document as an href by the generator."""
+    html = _html_with_source_url("javascript:alert(1)")
+    assert 'href="javascript:' not in html
+    assert "href='javascript:" not in html