##1. はじめに
sleepの時間をランダムに設定できるようにします。

##2. 新規コマンド
最小値～最大値の範囲内でランダムな時間sleepするコマンドを作成します。

|コマンド|引数 |機能
|--------+------------------------------------------+----
|rusleep |スリープ時間(最小値), スリープ時間(最大値)|最小値～最大値の範囲内でランダムな時間sleepする。単位は秒。

##3. テストランナーの改修
random.uniform()でランダムな値を生成しsleep()に渡します。

test-runner.py

import random
（略）
def main():
（略）
    fval = 0.0
（略）
                elif cmd[0] == "rusleep":
                    fval = random.uniform(float(cmd[1]), float(cmd[2]))
                    cmd.append(str(fval))
                    sleep(fval)
（略）

##4. 実行結果
以下のコマンドで実行します。

> python test-runner.py rusleep

###4.1 テストスクリプト
最小値を1.0、最大値を2.0とし、100回実行するテストスクリプトです。

rusleep.csv

rusleep,1.0,2.0
（以下、同一内容を100行）

###4.2 テスト実行結果
平均値は1.497でした。

rusleep_result.csv

2021/03/03 21:40:28,rusleep,1.0,2.0,1.5323377896008619,OK
2021/03/03 21:40:30,rusleep,1.0,2.0,1.8266354990565334,OK
（略）
2021/03/03 21:42:56,rusleep,1.0,2.0,1.5044505776491246,OK
2021/03/03 21:42:57,rusleep,1.0,2.0,1.7092165168215359,OK

##5. おわりに

randomモジュールのおかげで数行程度のコーディングでsleepの時間をランダムに設定できるようになりました。
- 正規分布にしたいといったカスタマイズも容易にできます。
ヒストグラムを見ると多少凸凹してはいますが、十分ランダムと思います。

##付録A. test-runner.pyのソース

test-runner.py

#!/usr/bin/python3

#
# This software includes the work that is distributed
# in the Apache License 2.0
#

from time import sleep
import random
import sys
import codecs
import csv
import datetime
import serial
import pyvisa as visa
import cv2
from PIL import Image
import pyocr
import pyocr.builders
import platform
import subprocess
from subprocess import PIPE

UNINITIALIZED = 0xdeadbeef
NUM_OF_SERVO = 6

def serial_write(h, string):
    if h != UNINITIALIZED:
        string = string + '\n'
        string = str.encode(string)
        h.write(string)
        return True
    else:
        print("UART Not Initialized.")
        return False

def close_uart(h):
    if h != UNINITIALIZED:
        h.close()
    else:
        #print("UART Not Initialized.")
        pass

def open_dso():
    rm = visa.ResourceManager()
    resources = rm.list_resources()
    #print(resources)
    for resource in resources:
        #print(resource)
        try:
            dso = rm.open_resource(resource)
        except:
            print(resource, "Not Found.")
        else:
            print(resource, "Detected.")
            return dso

    #Throw an error to caller if none succeed.
    return dso

def open_cam(camera_number, width, height):
    h = cv2.VideoCapture(camera_number)
    h.set(cv2.CAP_PROP_FRAME_WIDTH, width)
    h.set(cv2.CAP_PROP_FRAME_HEIGHT, height)
    return h

def close_cam(cam):
    if cam != UNINITIALIZED:
        cam.release()

def capture_cam(cam, filename):
    if cam != UNINITIALIZED:
        _, img = cam.read()
        cv2.imwrite(filename, img)
        return True
    else:
        print("CAM Not Ready.")
        return False

def crop_img(filename_in, v, h, filename_out):
    img = cv2.imread(filename_in, cv2.IMREAD_COLOR)
    v0 = int(v.split(':')[0])
    v1 = int(v.split(':')[1])
    h0 = int(h.split(':')[0])
    h1 = int(h.split(':')[1])
    img2 = img[v0:v1, h0:h1]
    cv2.imwrite(filename_out, img2)
    return True

def open_ocr():
    ocr = pyocr.get_available_tools()
    if len(ocr) != 0:
        ocr = ocr[0]
    else:
        ocr = UNINITIALIZED
        print("OCR Not Ready.")
    return ocr

def exec_ocr(ocr, filename):
    try:
        txt = ocr.image_to_string(
            Image.open(filename),
            lang = "eng",
            builder = pyocr.builders.TextBuilder()
        )
    except:
        print("OCR Fail.")
    else:
        return txt

def exec_labelimg(filename, label_string):
    if platform.system() == "Windows" :
        python = "python"
        grep = "findstr"
    else:
        python = "python3"
        grep = "grep"

    cmd = python + \
          " label_image.py \
          --graph=c:\\tmp\\output_graph.pb \
          --labels=c:\\tmp\\output_labels.txt \
          --input_layer=Placeholder \
          --output_layer=final_result \
          --image=" + filename \
          + "|" + grep + " " + label_string
    print(cmd)
    log = subprocess.run(cmd, stdout=subprocess.PIPE, shell=True)
    ret = log.stdout.strip().decode("utf-8").split(" ")[1]
    return ret

def set_servo(uart, servo_id, servo_pos):
    if servo_id < 0 or servo_id >= NUM_OF_SERVO:
        print("Invalid Servo ID")
        return False
    
    if servo_pos < 0 or servo_pos > 180:
        print("Invalid Servo Position")
        return False
    
    if uart != UNINITIALIZED:
        serial_write(uart, "servoread")
        
        servo_position = uart.readline().strip().decode('utf-8')
        print(servo_position)
        
        # discard "OK"
        devnull = uart.readline().strip().decode('utf-8')
        
        current_pos = int(servo_position.split(' ')[servo_id])
        #print(servo_id, current_pos)
        
        if current_pos < servo_pos:
            start = current_pos +1
            stop  = servo_pos +1
            step  = 1
        else:
            start = current_pos -1
            stop  = servo_pos -1
            step  = -1
            
        for i in range(start, stop, step):
            command = "servo " + str(servo_id) + " " + str(i)
            print(command)
            serial_write(uart, command)
            # discard "OK"
            devnull = uart.readline().strip().decode('utf-8')
            sleep(0.2) # sec.
            
        return True
    else:
        print("UART Not Initialized.")
        return False

def main():
    is_passed = True
    val = str(UNINITIALIZED)
    fval = 0.0
    uart = UNINITIALIZED
    dso = UNINITIALIZED
    cam = UNINITIALIZED
    ocr = UNINITIALIZED

    if len(sys.argv) == 2:
        script_file_name = sys.argv[1] + ".csv"
        result_file_name = sys.argv[1] + "_result.csv"
    else:
        script_file_name = "script.csv"
        result_file_name = "result.csv"

    with codecs.open(script_file_name, 'r', 'utf-8') as file:
        script = csv.reader(file, delimiter=',', lineterminator='\r\n', quotechar='"')

        with codecs.open(result_file_name, 'w', 'utf-8') as file:
            result = csv.writer(file, delimiter=',', lineterminator='\r\n', quotechar='"')

            for cmd in script:
                timestamp = datetime.datetime.now().strftime("%Y/%m/%d %H:%M:%S")
                print(cmd)

                if "#" in cmd[0]:
                    pass

                elif cmd[0] == "sleep":
                    sleep(float(cmd[1]))

                elif cmd[0] == "rusleep":
                    fval = random.uniform(float(cmd[1]), float(cmd[2]))
                    cmd.append(str(fval))
                    sleep(fval)

                elif cmd[0] == "open_uart":
                    if len(cmd) == 2:
                        dsrdtr_val = 1
                    else:
                        dsrdtr_val = int(cmd[2])
                    try:
                        uart = serial.Serial(cmd[1], 115200, timeout=1.0, dsrdtr=dsrdtr_val)
                    except:
                        is_passed = False

                elif cmd[0] == "send":
                    ret = serial_write(uart, cmd[1])
                    if ret == False:
                        is_passed = False

                elif cmd[0] == "rcvd":
                    try:
                        val = uart.readline().strip().decode('utf-8')
                        cmd.append(val)
                    except:
                        is_passed = False

                elif cmd[0] == "open_dso":
                    try:
                        dso = open_dso()
                    except:
                        is_passed = False

                elif cmd[0] == "dso":
                    try:
                        if "?" in cmd[1]:
                            val = dso.query(cmd[1]).rstrip().replace(",", "-")
                            cmd.append(val)
                        else:
                            dso.write(cmd[1])
                    except:
                        is_passed = False

                elif cmd[0] == "open_cam":
                    if len(cmd) == 2:
                        cam = open_cam(int(cmd[1]), 640, 480)
                    else:
                        cam = open_cam(int(cmd[1]), int(cmd[2]), int(cmd[3]))

                elif cmd[0] == "close_cam":
                    close_cam(cam)
                    cam = UNINITIALIZED

                elif cmd[0] == "capture_cam":
                    ret = capture_cam(cam, cmd[1])
                    if ret == False:
                        is_passed = False

                elif cmd[0] == "crop_img":
                    crop_img(cmd[1], cmd[2], cmd[3], cmd[4])

                elif cmd[0] == "open_ocr":
                    ocr = open_ocr()
                    if ocr == UNINITIALIZED:
                        is_passed = False

                elif cmd[0] == "exec_ocr":
                    try:
                        val = exec_ocr(ocr, cmd[1])
                    except:
                        is_passed = False
                    else:
                        cmd.append(str(val))

                elif cmd[0] == "exec_labelimg":
                    try:
                        val = exec_labelimg(cmd[1], cmd[2])
                    except:
                        is_passed = False
                    else:
                        cmd.append(str(val))

                elif cmd[0] == "set_servo":
                    ret = set_servo(uart, int(cmd[1]), int(cmd[2]))
                    if ret == False:
                        is_passed = False

                elif cmd[0] == "run":
                    ret = subprocess.run(cmd[1], shell=True, stdout=PIPE, stderr=PIPE, universal_newlines=True)
                    val = ret.stdout.strip()
                    print(ret)
                    if ret.returncode != 0:
                        is_passed = False

                elif cmd[0] == "eval_str_eq":
                    if str(val) != str(cmd[1]):
                        is_passed = False

                elif cmd[0] == "eval_int_eq":
                    if int(val) != int(cmd[1]):
                        is_passed = False

                elif cmd[0] == "eval_int_gt":
                    if int(val) < int(cmd[1]):
                        is_passed = False

                elif cmd[0] == "eval_int_lt":
                    if int(val) > int(cmd[1]):
                        is_passed = False

                elif cmd[0] == "eval_dbl_eq":
                    if float(val) != float(cmd[1]):
                        is_passed = False

                elif cmd[0] == "eval_dbl_gt":
                    if float(val) < float(cmd[1]):
                        is_passed = False

                elif cmd[0] == "eval_dbl_lt":
                    if float(val) > float(cmd[1]):
                        is_passed = False

                else:
                    cmd.append("#")

                if is_passed == True:
                    cmd.append("OK")
                    cmd.insert(0,timestamp)
                    print(cmd)
                    result.writerow(cmd)
                else:
                    cmd.append("NG")
                    cmd.insert(0,timestamp)
                    print(cmd)
                    result.writerow(cmd)
                    close_uart(uart)
                    close_cam(cam)
                    print("FAIL")
                    sys.exit(1)

    if is_passed == True:
        close_uart(uart)
        close_cam(cam)
        print("PASS")
        sys.exit(0)

main()

##付録B. Lチカで始めるテスト自動化・記事一覧

電子書籍化したものを技術書典で頒布しています。