Initial public release — aci-sim v0.16.0

aci-sim is a stateful REST simulator of a 2-site Cisco ACI fabric
(per-site APIC + ND/NDO management planes) — for testing ACI automation
(Ansible cisco.aci / cisco.mso, aci-py, custom REST clients) and CI gates
without real hardware.

Highlights: APIC + NDO REST surface served from one in-memory MIT built
from a declarative topology.yaml; port mode + sandbox (real per-device IPs
on :443) run modes; LLDP/CDP neighbor visibility; NDO->APIC deploy mirror
(multi-site templates materialize onto the target sites' APIC stores);
real-APIC fvBD default attributes; file-backed state save/restore; an
`aci-sim` CLI (validate/show/graph/run/new/init/lldp); and an 888-test suite.

History squashed for the public release.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

tests/test_graph.py

@@ -0,0 +1,185 @@
+"""Tests for aci_sim/graph.py — self-contained SVG/HTML topology diagram.
+
+Covers `render_topology()` directly (node counts, ISN cloud presence/absence,
+role colors, well-formed XML) plus the `aci-sim graph` CLI subcommand. No
+browser is required anywhere — every assertion works on the raw string
+output.
+"""
+
+from __future__ import annotations
+
+import re
+import xml.etree.ElementTree as ET
+from pathlib import Path
+
+from aci_sim.cli import generate_topology, main
+from aci_sim.graph import ROLE_COLORS, build_graph, render_topology
+from aci_sim.topology.loader import load_topology
+from aci_sim.topology.schema import Topology
+
+
+def _new_topology(sites: int) -> Topology:
+    """Build a fresh N-site Topology via cli.generate_topology() (returns a dict)."""
+    raw = generate_topology(sites=sites)
+    return Topology.model_validate(raw)
+
+
+REPO_ROOT = Path(__file__).parent.parent
+TOPOLOGY_YAML = REPO_ROOT / "topology.yaml"
+
+
+def _total_node_count(topo) -> int:
+    total = 0
+    for site in topo.sites:
+        total += len(site.spine_nodes()) + len(site.leaf_nodes()) + len(site.border_leaves)
+        total += site.controllers
+    return total
+
+
+def _svg_fragment(html: str) -> str:
+    m = re.search(r"<svg.*</svg>", html, re.S)
+    assert m, "no <svg>...</svg> fragment found"
+    return m.group(0)
+
+
+class TestRenderTopologyRepoDefault:
+    """The repo's default topology.yaml is a 2-site, ISN-enabled fabric."""
+
+    def test_html_contains_svg(self) -> None:
+        topo = load_topology(TOPOLOGY_YAML)
+        html = render_topology(topo, fmt="html")
+        assert "<svg" in html
+        assert html.startswith("<html")
+
+    def test_svg_format_starts_with_svg_tag(self) -> None:
+        topo = load_topology(TOPOLOGY_YAML)
+        svg = render_topology(topo, fmt="svg")
+        assert svg.startswith("<svg")
+        assert "</svg>" in svg
+
+    def test_node_rect_count_matches_topology(self) -> None:
+        topo = load_topology(TOPOLOGY_YAML)
+        svg = render_topology(topo, fmt="svg")
+        node_groups = re.findall(r'<g class="node node-[a-z-]+"', svg)
+        expected = _total_node_count(topo)  # ISN cloud is the +1 (checked separately)
+        assert len(node_groups) == expected + 1  # +1 for the ISN cloud node
+
+    def test_isn_cloud_present_for_multisite(self) -> None:
+        topo = load_topology(TOPOLOGY_YAML)
+        assert topo.isn.enabled and len(topo.sites) > 1
+        svg = render_topology(topo, fmt="svg")
+        assert 'class="node node-isn"' in svg
+        assert "ISN" in svg
+
+    def test_role_colors_present(self) -> None:
+        topo = load_topology(TOPOLOGY_YAML)
+        svg = render_topology(topo, fmt="svg")
+        for role in ("spine", "leaf", "border-leaf", "controller", "isn"):
+            fill, _border = ROLE_COLORS[role]
+            assert fill in svg, f"expected {role} fill color {fill} in output"
+
+    def test_output_is_well_formed_xml(self) -> None:
+        topo = load_topology(TOPOLOGY_YAML)
+        svg = render_topology(topo, fmt="svg")
+        ET.fromstring(svg)  # raises if malformed
+
+    def test_html_output_is_well_formed_xml_fragment(self) -> None:
+        topo = load_topology(TOPOLOGY_YAML)
+        html = render_topology(topo, fmt="html")
+        ET.fromstring(_svg_fragment(html))
+
+    def test_legend_present(self) -> None:
+        topo = load_topology(TOPOLOGY_YAML)
+        svg = render_topology(topo, fmt="svg")
+        assert 'class="legend"' in svg
+        assert "Spine" in svg and "Leaf" in svg and "Border Leaf" in svg
+
+    def test_title_contains_fabric_name_and_site_count(self) -> None:
+        topo = load_topology(TOPOLOGY_YAML)
+        svg = render_topology(topo, fmt="svg")
+        assert topo.fabric.name in svg
+        assert f"{len(topo.sites)} site(s)" in svg
+
+
+class TestSingleFabricNoIsn:
+    def test_single_site_omits_isn_cloud(self) -> None:
+        single = _new_topology(sites=1)
+        assert len(single.sites) == 1  # sanity: no ISN possible with 1 site
+        svg = render_topology(single, fmt="svg")
+        assert 'class="node node-isn"' not in svg
+        ET.fromstring(svg)
+
+
+class TestThreeSiteTopology:
+    def test_three_sites_all_render(self) -> None:
+        topo = _new_topology(sites=3)
+        assert len(topo.sites) == 3
+        svg = render_topology(topo, fmt="svg")
+        ET.fromstring(svg)
+        for site in topo.sites:
+            assert site.name in svg
+        node_groups = re.findall(r'<g class="node node-[a-z-]+"', svg)
+        assert len(node_groups) == _total_node_count(topo) + 1  # +1 ISN cloud
+        assert 'class="node node-isn"' in svg
+
+
+class TestBuildGraph:
+    def test_build_graph_node_and_link_counts(self) -> None:
+        topo = load_topology(TOPOLOGY_YAML)
+        graph = build_graph(topo)
+        assert graph.node_count() == _total_node_count(topo) + 1  # + ISN cloud
+        assert graph.site_count == len(topo.sites)
+        # every link references a node that exists in the graph
+        node_ids = {n.id for n in graph.nodes}
+        for link in graph.links:
+            assert link.source in node_ids
+            assert link.target in node_ids
+
+    def test_vpc_pair_links_present(self) -> None:
+        topo = load_topology(TOPOLOGY_YAML)
+        graph = build_graph(topo)
+        vpc_links = [link for link in graph.links if link.kind == "vpc"]
+        assert len(vpc_links) >= 1  # LAB1 + LAB2 each have one vPC pair
+
+
+class TestGraphCLI:
+    def test_cli_graph_writes_html_file(self, tmp_path, capsys) -> None:
+        out_file = tmp_path / "g.html"
+        rc = main(["graph", str(TOPOLOGY_YAML), "-o", str(out_file)])
+        out = capsys.readouterr().out
+        assert rc == 0
+        assert out_file.exists()
+        content = out_file.read_text(encoding="utf-8")
+        assert content.startswith("<html")
+        assert "<svg" in content
+        assert str(out_file) in out
+
+    def test_cli_graph_writes_svg_file(self, tmp_path) -> None:
+        out_file = tmp_path / "g.svg"
+        rc = main(["graph", str(TOPOLOGY_YAML), "-o", str(out_file)])
+        assert rc == 0
+        content = out_file.read_text(encoding="utf-8")
+        assert content.startswith("<svg")
+
+    def test_cli_graph_default_topology_and_output(self, tmp_path, monkeypatch) -> None:
+        monkeypatch.chdir(REPO_ROOT)
+        out_file = REPO_ROOT / "topology.html"
+        try:
+            rc = main(["graph", "-o", str(tmp_path / "default_out.html")])
+            assert rc == 0
+        finally:
+            if out_file.exists():
+                out_file.unlink()
+
+    def test_cli_graph_unknown_extension_errors(self, tmp_path, capsys) -> None:
+        out_file = tmp_path / "g.png"
+        rc = main(["graph", str(TOPOLOGY_YAML), "-o", str(out_file)])
+        err = capsys.readouterr().err
+        assert rc != 0
+        assert "ERROR" in err
+
+    def test_cli_graph_missing_topology_errors(self, tmp_path, capsys) -> None:
+        rc = main(["graph", "/nonexistent/topology.yaml", "-o", str(tmp_path / "g.html")])
+        err = capsys.readouterr().err
+        assert rc != 0
+        assert "ERROR" in err