ASCII art server timing bar graph from response object

ascii_server_timing.py

"""
Parse and display Server-Timing header info
"""

import shutil


def timing_string_to_dict(server_timing_string):
    """
    Given a Server Timing value as a string, parse it into a dict of the format
      nice_name: value

    For example

      'a=1, "alpha"; b=2'

    will parse as

      {"alpha": 1, "b": 2}

    """

    def parse_item(item):
        item = [x.strip() for x in item.split(";")]
        assert len(item) <= 2, "Too many semicolons in timing item, cannot parse"
        nice_name = None
        if len(item) == 2:
            nice_name = item[1].strip('"')
            item = item[0]
        item = item.split("=")
        assert len(item) == 2, "Wrong number of '=' delimited values"
        if not nice_name:
            nice_name = item[0]
        return (nice_name, float(item[1]))

    items = [x.strip() for x in server_timing_string.split(",")]
    return {key: value for (key, value) in [parse_item(x) for x in items]}


def render_dict_onscreen(timing_dict):
    term_width = shutil.get_terminal_size((80, 20)).columns
    use_width = term_width - 4

    items = sorted(list(timing_dict.items()), key=lambda x: x[1])
    items = [("{}={}".format(*item), item[1]) for item in items]
    last = items[-1]
    factor = last[1]
    desc_width = (max(len(x[0]) for x in items) if items else 0) + 1

    print("+" + "-" * (term_width - 2) + "+")
    for desc, size in items:
        desc = desc.ljust(desc_width, ".")
        bar_width = max(int((use_width - desc_width) * size / factor), 1)
        msg = (desc + "#" * bar_width).ljust(use_width, " ")
        print("| {} |".format(msg))
    print("+" + "-" * (term_width - 2) + "+")


def render_timing_from_response(response):
    timing_str = response._data.headers.get("Server-Timing")
    if timing_str:
        render_dict_onscreen(timing_string_to_dict(timing_str))

example-output.txt

+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+
| Query Parsing Time=0.14.......#                                                                                                                                                   |
| query_exec_build_query=0.34...#                                                                                                                                                   |
| query_exec_render_result=5.58.##                                                                                                                                                  |
| raw_query_exec=15.89..........######                                                                                                                                              |
| query_exec_invoke=17.83.......######                                                                                                                                              |
| Query Execution Time=23.99....#########                                                                                                                                           |
| overall=128.38................#################################################                                                                                                   |
| groupauth=178.64..............####################################################################                                                                                |
| auth=249.05...................###############################################################################################                                                     |
| total=382.72..................################################################################################################################################################### |
+-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------+