# -*- coding: utf-8 -*-
"""Location: ./mcp-servers/python/graphviz_server/tests/test_server.py
Copyright 2025
SPDX-License-Identifier: Apache-2.0
Authors: Mihai Criveti
Tests for Graphviz MCP Server (FastMCP).
"""
import tempfile
from pathlib import Path
from unittest.mock import MagicMock, patch
from graphviz_server.server_fastmcp import processor
def test_create_graph():
"""Test creating a DOT graph."""
with tempfile.TemporaryDirectory() as tmpdir:
file_path = str(Path(tmpdir) / "test.dot")
result = processor.create_graph(
file_path=file_path,
graph_type="digraph",
graph_name="TestGraph",
attributes={"rankdir": "TB", "bgcolor": "white"},
)
assert result["success"] is True
assert Path(file_path).exists()
assert result["graph_type"] == "digraph"
assert result["graph_name"] == "TestGraph"
# Check file content
with open(file_path) as f:
content = f.read()
assert "digraph TestGraph {" in content
assert 'rankdir="TB"' in content
assert 'bgcolor="white"' in content
def test_add_node():
"""Test adding a node to a graph."""
with tempfile.TemporaryDirectory() as tmpdir:
file_path = str(Path(tmpdir) / "test.dot")
# Create graph first
processor.create_graph(file_path=file_path, graph_type="digraph")
# Add node
result = processor.add_node(
file_path=file_path,
node_id="node1",
label="Test Node",
attributes={"shape": "box", "color": "blue"},
)
assert result["success"] is True
assert result["node_id"] == "node1"
assert result["label"] == "Test Node"
# Check file content
with open(file_path) as f:
content = f.read()
assert 'node1 [label="Test Node", shape="box", color="blue"];' in content
def test_add_edge():
"""Test adding an edge to a graph."""
with tempfile.TemporaryDirectory() as tmpdir:
file_path = str(Path(tmpdir) / "test.dot")
# Create graph first
processor.create_graph(file_path=file_path, graph_type="digraph")
# Add edge
result = processor.add_edge(
file_path=file_path,
from_node="A",
to_node="B",
label="edge1",
attributes={"color": "red", "style": "bold"},
)
assert result["success"] is True
assert result["from_node"] == "A"
assert result["to_node"] == "B"
assert result["label"] == "edge1"
# Check file content
with open(file_path) as f:
content = f.read()
assert 'A -> B [label="edge1", color="red", style="bold"];' in content
def test_analyze_graph():
"""Test analyzing a graph."""
with tempfile.TemporaryDirectory() as tmpdir:
file_path = str(Path(tmpdir) / "test.dot")
# Create a graph with some content
graph_content = """digraph TestGraph {
rankdir=TB;
A [label="Node A"];
B [label="Node B"];
C [label="Node C"];
A -> B [label="edge1"];
B -> C [label="edge2"];
A -> C [label="edge3"];
}"""
with open(file_path, "w") as f:
f.write(graph_content)
result = processor.analyze_graph(
file_path=file_path, include_structure=True, include_metrics=True
)
assert result["success"] is True
assert "structure" in result
assert "metrics" in result
# Check structure analysis
structure = result["structure"]
assert structure["edge_count"] == 3 # A->B, B->C, A->C
@patch("graphviz_server.server_fastmcp.subprocess.run")
def test_validate_graph_success(mock_subprocess):
"""Test successful graph validation."""
# Mock successful validation
mock_result = MagicMock()
mock_result.returncode = 0
mock_result.stdout = "validation successful"
mock_result.stderr = ""
mock_subprocess.return_value = mock_result
with tempfile.TemporaryDirectory() as tmpdir:
file_path = str(Path(tmpdir) / "test.dot")
# Create a valid DOT file
with open(file_path, "w") as f:
f.write("digraph G { A -> B; }")
result = processor.validate_graph(file_path=file_path)
assert result["success"] is True
assert result["file_path"] == file_path
def test_set_attributes():
"""Test setting graph attributes."""
with tempfile.TemporaryDirectory() as tmpdir:
file_path = str(Path(tmpdir) / "test.dot")
# Create graph first
processor.create_graph(file_path=file_path, graph_type="digraph")
# Set graph attributes
result = processor.set_attributes(
file_path=file_path,
target_type="graph",
attributes={"splines": "curved", "overlap": "false"},
)
assert result["success"] is True
# Check file content
with open(file_path) as f:
content = f.read()
assert 'splines="curved"' in content
assert 'overlap="false"' in content
def test_create_graph_missing_directory():
"""Test creating graph in non-existent directory."""
with tempfile.TemporaryDirectory() as tmpdir:
file_path = str(Path(tmpdir) / "subdir" / "test.dot")
result = processor.create_graph(file_path=file_path, graph_type="digraph")
assert result["success"] is True
# Should create directory and file
assert Path(file_path).exists()
assert Path(file_path).parent.exists()
def test_list_layouts():
"""Test listing layouts and formats."""
result = processor.list_layouts()
assert result["success"] is True
assert "layouts" in result
assert "formats" in result
assert "dot" in result["layouts"]
assert "png" in result["formats"]
def test_add_node_duplicate():
"""Test adding duplicate node to a graph."""
with tempfile.TemporaryDirectory() as tmpdir:
file_path = str(Path(tmpdir) / "test.dot")
# Create graph and add a node
processor.create_graph(file_path=file_path, graph_type="digraph")
processor.add_node(file_path=file_path, node_id="node1")
# Try to add the same node again
result = processor.add_node(file_path=file_path, node_id="node1")
assert result["success"] is False
assert "already exists" in result["error"]
def test_undirected_graph_edge():
"""Test adding edge to undirected graph uses correct operator."""
with tempfile.TemporaryDirectory() as tmpdir:
file_path = str(Path(tmpdir) / "test.dot")
# Create undirected graph
processor.create_graph(file_path=file_path, graph_type="graph")
# Add edge
result = processor.add_edge(file_path=file_path, from_node="A", to_node="B")
assert result["success"] is True
# Check file content for undirected edge operator
with open(file_path) as f:
content = f.read()
assert "A -- B;" in content
assert "A -> B" not in content # Should not have directed edge
