Files
dmlc--dgl/tests/tools/test_parmetis_preproc.py
2026-07-13 13:35:51 +08:00

178 lines
6.2 KiB
Python

import os
import tempfile
from collections import namedtuple
import numpy as np
import pytest
from distpartitioning import array_readwriter, constants
from distpartitioning.parmetis_preprocess import gen_edge_files
from distpartitioning.utils import generate_roundrobin_read_list
from numpy.testing import assert_array_equal
NODE_TYPE = "n1"
EDGE_TYPE = f"{NODE_TYPE}:e1:{NODE_TYPE}"
def _read_file(fname, fmt_name, fmt_delimiter):
"""Read a file
Parameters:
-----------
fname : string
filename of the input file to read
fmt_name : string
specifying whether it is a csv or a parquet file
fmt_delimiter : string
string specifying the delimiter used in the input file
"""
reader_fmt_meta = {
"name": fmt_name,
}
if fmt_name == constants.STR_CSV:
reader_fmt_meta["delimiter"] = fmt_delimiter
data_df = array_readwriter.get_array_parser(**reader_fmt_meta).read(fname)
return data_df
def _get_test_data(edges_dir, num_chunks, edge_fmt, edge_fmt_del):
"""Creates unit test input which are a set of edge files
in the following format "src_node_id<delimiter>dst_node_id"
Parameters:
-----------
edges_dir : str
folder where edge files are stored
num_chunks : int
no. of files to create for each edge type
edge_fmt : str, optional
to specify whether this file is csv or parquet
edge_fmt_del : str optional
delimiter to use in the edges file
Returns:
--------
dict :
dictionary created which represents the schema used for
creating the input dataset
"""
schema = {}
schema["num_nodes_per_type"] = [10]
schema["edge_type"] = [EDGE_TYPE]
schema["node_type"] = [NODE_TYPE]
edges = {}
edges[EDGE_TYPE] = {}
edges[EDGE_TYPE]["format"] = {}
edges[EDGE_TYPE]["format"]["name"] = edge_fmt
edges[EDGE_TYPE]["format"]["delimiter"] = edge_fmt_del
os.makedirs(edges_dir, exist_ok=True)
fmt_meta = {"name": edge_fmt}
if edge_fmt == "csv":
fmt_meta["delimiter"] = edge_fmt_del
edge_files = []
for idx in range(num_chunks):
path = os.path.join(edges_dir, f"test_file_{idx}.{fmt_meta['name']}")
array_parser = array_readwriter.get_array_parser(**fmt_meta)
edge_data = (
np.array([np.arange(10), np.arange(10)]).reshape(10, 2) + 10 * idx
)
array_parser.write(path, edge_data)
edge_files.append(path)
edges[EDGE_TYPE]["data"] = edge_files
schema["edges"] = edges
return schema
@pytest.mark.parametrize("num_chunks, num_parts", [[4, 1], [4, 2], [4, 4]])
@pytest.mark.parametrize("edges_fmt", ["csv", "parquet"])
@pytest.mark.parametrize("edges_delimiter", [" ", ","])
def test_gen_edge_files(num_chunks, num_parts, edges_fmt, edges_delimiter):
"""Unit test case for the function
tools/distpartitioning/parmetis_preprocess.py::gen_edge_files
Parameters:
-----------
num_chunks : int
no. of chunks the input graph needs to be partititioned into
num_parts : int
no. of partitions
edges_fmt : string
specifying the storage format for the edge files
edges_delimiter : string
specifying the delimiter used in the edge files
"""
# Create the input dataset
with tempfile.TemporaryDirectory() as root_dir:
# Create expected environment for test
input_dir = os.path.join(root_dir, "chunked-data")
output_dir = os.path.join(root_dir, "preproc_dir")
# Mock a parser object
fn_params = namedtuple("fn_params", "input_dir output_dir num_parts")
fn_params.input_dir = input_dir
fn_params.output_dir = output_dir
fn_params.num_parts = num_parts
# Create test files and get corresponding file schema
schema_map = _get_test_data(
input_dir, num_chunks, edges_fmt, edges_delimiter
)
edges_file_list = schema_map["edges"][EDGE_TYPE]["data"]
# This is breaking encapsulation, but no other good way to get file list
rank_assignments = generate_roundrobin_read_list(
len(edges_file_list), num_parts
)
# Get the global node id offsets for each node type
# There is only one node-type in the test graph
# which range from 0 thru 9.
ntype_gnid_offset = {}
ntype_gnid_offset[NODE_TYPE] = np.array([0, 10 * num_chunks]).reshape(
1, 2
)
# Iterate over no. of partitions
for rank in range(num_parts):
actual_results = gen_edge_files(rank, schema_map, fn_params)
# Get the original files
original_files = [
edges_file_list[file_idx] for file_idx in rank_assignments[rank]
]
# Validate the results with the baseline results
# Test 1. no. of files should have the same count per rank
assert len(original_files) == len(actual_results)
assert len(actual_results) > 0
# Test 2. Check the contents of each file and verify the
# file contents match with the expected results.
for actual_fname, original_fname in zip(
actual_results, original_files
):
# Check the actual file exists
assert os.path.isfile(actual_fname)
# Read both files and compare the edges
# Here note that the src and dst end points are global_node_ids
actual_data = _read_file(actual_fname, "csv", " ")
expected_data = _read_file(
original_fname, edges_fmt, edges_delimiter
)
# Subtract the global node id offsets, so that we get type node ids
# In the current unit test case, the graph has only one node-type.
# and this means that type-node-ids are same as the global-node-ids.
# Below two lines will take take into effect when the graphs have
# more than one node type.
actual_data[:, 0] -= ntype_gnid_offset[NODE_TYPE][0, 0]
actual_data[:, 1] -= ntype_gnid_offset[NODE_TYPE][0, 0]
# Verify that the contents are equal
assert_array_equal(expected_data, actual_data)