generate_benchmark_summaries.py

"""
Small utility to take pytest-benchmark results and update our README.md with
them.
"""
import sys
import json
from datetime import datetime

from pytest_benchmark.utils import slugify
from humanmark import Fragment, load, HTMLBlock, Header, Text, Paragraph, dump, \
    Image, BlockQuote


def main(argv):
    with open('benchmark.json') as src:
        j = json.load(src)

    groups = {}
    for benchmark in j['benchmarks']:
        groups.setdefault(benchmark['group'], []).append(benchmark)

    readme_summaries = Fragment()
    for group_name, result in groups.items():
        result.sort(key=lambda v: v['stats']['min'])

        readme_summaries.extend((
            Header(3, children=[Text(group_name)]),
        ))

        row = result[0]
        if 'file' in row['extra_info']:
            readme_summaries.extend((
                Paragraph(children=[
                    Text(
                        f'Sample file is {row["extra_info"]["file_size"]}'
                        ' bytes.'
                    )
                ]),
            ))

        readme_summaries.extend((
            Paragraph(children=[
                # Not sure why the CLI generates an extra prefixed '-' on
                # the filename.
                Image(
                    f'histograms/-{slugify(group_name)}.svg',
                    title=f'Histogram for {group_name}.'
                )
            ])
        ))

        readme_summaries.extend((
            Paragraph(children=[
                Text(
                    '| library '
                    '| min (ms) '
                    '| max (ms) '
                    '| mean (ms) '
                    '|\n'
                ),
                Text(
                    '| ------- '
                    '| -------- '
                    '| -------- '
                    '| --------- '
                    '|\n'
                ),
                *(
                    Text(
                        f'| {v["name"]} '
                        f'| {v["stats"]["min"] * 1000:.4f} '
                        f'| {v["stats"]["max"] * 1000:.4f} '
                        f'| {v["stats"]["mean"] * 1000:.4f} '
                        f'|\n'
                    )
                    for v in result
                )
            ]),
        ))

    with open('README.md') as src:
        readme = load(src)

    start = readme.find_one(
        HTMLBlock,
        f=lambda block: block.content == (
            '<!-- start_performance_block -->\n'
        )
    )

    end = readme.find_one(
        HTMLBlock,
        f=lambda block: block.content == '<!-- end_performance_block -->\n'
    )

    # Erase all the content between the open and closing blocks.
    node = start.next
    while node:
        if node == end:
            break

        node = node.delete()

    start.append_sibling(readme_summaries)

    start = readme.find_one(
        HTMLBlock,
        f=lambda block: block.content == (
            '<!-- start_last_updated_block -->\n'
        )
    )

    end = readme.find_one(
        HTMLBlock,
        f=lambda block: block.content == (
            '<!-- end_last_updated_block -->\n'
        )
    )

    node = start.next
    while node:
        if node == end:
            break

        node = node.delete()

    start.append_sibling(
        Fragment(children=[
            BlockQuote(children=[
                Text(
                    ':grey_exclamation: Benchmarks regenerated on '
                    f'{datetime.utcnow().strftime("%Y-%m-%d")}'
                )
            ])
        ])
    )

    with open('README.md', 'w') as out:
        dump(readme, out)


if __name__ == '__main__':
    sys.exit(main(sys.argv))