extras: add example for asyncio

extras/kitchen_asyncio/kitchen_serial.py

@@ -0,0 +1,83 @@
+import argparse
+import random
+import time
+
+def do_work(duration, result):
+    t = random.uniform(duration/5 * 0.5, duration/5 * 1.5)
+    time.sleep(t)
+    return result
+
+def fetch_olive_oil():
+    print('Fetching olive oil…')
+    return do_work(5, 'oil')
+
+def fetch_dako_rusk():
+    print('Fetching dako rusk…')
+    return do_work(5, 'rusk')
+
+def fetch_tomato():
+    print('Fetching tomato…')
+    return do_work(3, 'tomato')
+
+def fetch_feta():
+    print('Fetching feta…')
+    return do_work(3, 'feta')
+
+def chop_tomato(tomato):
+    assert tomato == 'tomato'
+    print('Chopping tomato…')
+    return do_work(1, f'chopped {tomato}')
+
+def water_rusk(rusk):
+    assert rusk == 'rusk'
+    print('Watering rusk…')
+    return do_work(0.2, f'wet {rusk}')
+
+def oil_rusk(rusk, oil):
+    assert rusk == 'wet rusk'
+    assert oil == 'oil'
+    print(f'Pouring {oil} on {rusk}…')
+    return do_work(0.5, f'{rusk} with {oil}')
+
+def decorate_rusk(rusk, *toppings):
+    result = rusk
+    for topping in toppings:
+        print(f'Putting {topping} on {result}…')
+        result = do_work(1, f'{result} with {topping}')
+    return result
+
+def store_dako(dako):
+    print(f'Storing {dako}')
+    do_work(1, None)
+
+def prepare_dako():
+    print('Making dako…')
+    oil = fetch_olive_oil()
+    rusk = fetch_dako_rusk()
+    tomato = fetch_tomato()
+    tomato = chop_tomato(tomato)
+    rusk = water_rusk(rusk)
+    rusk = oil_rusk(rusk, oil)
+    feta = fetch_feta()
+    dako = decorate_rusk(rusk, tomato, feta)
+    store_dako(dako)
+    print(f'{dako} is ready!')
+
+def prepare_dakos(n_dakos):
+    for n in range(args.n_dakos):
+        prepare_dako()
+
+def parse_args():
+    p = argparse.ArgumentParser()
+    p.add_argument(
+        'n_dakos',
+        type=int,
+        nargs='?',
+        default=1,
+        help='How many dakos to make?',
+    )
+    return p.parse_args()
+
+if __name__ == '__main__':
+    args = parse_args()
+    prepare_dakos(args.n_dakos)