From dfda6924c0d531512d52b78e0c53556d0b350f51 Mon Sep 17 00:00:00 2001 From: Andrey Rudakov Date: Tue, 22 Sep 2026 21:59:55 +0300 Subject: [PATCH 01/10] Solve Task 1 --- src/part1/constants.py | 21 +++++++++++++-------- src/part1/snowflake.py | 43 ++++++++++++++++++++++++++++++------------ 2 files changed, 44 insertions(+), 20 deletions(-) diff --git a/src/part1/constants.py b/src/part1/constants.py index 9abfbba2..fec8d028 100644 --- a/src/part1/constants.py +++ b/src/part1/constants.py @@ -19,20 +19,25 @@ # Все константы, зависящие от ёмкостей *_BITS, должны вычисляться из них. # Twitter's original Snowflake epoch: 2010-11-04 01:42:54.657 UTC. -EPOCH_MS_DEFAULT: Final[int] = 0 +EPOCH_MS_DEFAULT: Final[int] = 1288834974657 # Node identifier used when the caller does not supply one. -NODE_ID_DEFAULT: Final[int] = 0 +NODE_ID_DEFAULT: Final[int] = 1 # Width of each field, in bits. -TIMESTAMP_BITS: Final[int] = 0 -NODE_ID_BITS: Final[int] = 0 -SEQUENCE_ID_BITS: Final[int] = 0 +TIMESTAMP_BITS: Final[int] = 41 +NODE_ID_BITS: Final[int] = 10 +SEQUENCE_ID_BITS: Final[int] = 12 # Largest value each field can hold. -TIMESTAMP_MS_MAX: Final[int] = 0 -NODE_ID_MAX: Final[int] = 0 -SEQUENCE_ID_MAX: Final[int] = 0 +TIMESTAMP_MS_MAX: Final[int] = (1 << TIMESTAMP_BITS) - 1 +NODE_ID_MAX: Final[int] = (1 << NODE_ID_BITS) - 1 +SEQUENCE_ID_MAX: Final[int] = (1 << SEQUENCE_ID_BITS) - 1 # Здесь можно добавить собственные вспомогательные константы # (например, сдвиги полей при сборке идентификатора). + +# Shift amounts +SEQUENCE_ID_SHIFT = 0 +NODE_ID_SHIFT = SEQUENCE_ID_BITS +TIMESTAMP_SHIFT = SEQUENCE_ID_BITS + NODE_ID_BITS diff --git a/src/part1/snowflake.py b/src/part1/snowflake.py index d3abf050..979a38a0 100644 --- a/src/part1/snowflake.py +++ b/src/part1/snowflake.py @@ -13,14 +13,16 @@ :func:`decode_node_id` and :func:`decode_sequence_id`. """ -import time # noqa: F401 +import time -from .constants import ( # noqa: F401 +from .constants import ( EPOCH_MS_DEFAULT, NODE_ID_DEFAULT, NODE_ID_MAX, + NODE_ID_SHIFT, SEQUENCE_ID_MAX, TIMESTAMP_MS_MAX, + TIMESTAMP_SHIFT, ) @@ -34,8 +36,7 @@ def read_current_millis(epoch_ms: int) -> int: The count of whole milliseconds between ``epoch_ms`` and now. May be negative if ``epoch_ms`` lies in the future. """ - # TODO: реализуйте функцию - return 0 + return int(time.time() * 1000) - epoch_ms def decode_timestamp_ms(snowflake_id: int, epoch_ms: int = EPOCH_MS_DEFAULT) -> int: @@ -50,8 +51,8 @@ def decode_timestamp_ms(snowflake_id: int, epoch_ms: int = EPOCH_MS_DEFAULT) -> The absolute Unix time in milliseconds at which the identifier was generated. """ - # TODO: реализуйте функцию - return 0 + stored_ms = (snowflake_id >> TIMESTAMP_SHIFT) & TIMESTAMP_MS_MAX + return stored_ms + epoch_ms def decode_node_id(snowflake_id: int) -> int: @@ -64,8 +65,7 @@ def decode_node_id(snowflake_id: int) -> int: The node identifier packed into ``snowflake_id``, in the range ``[0, NODE_ID_MAX]``. """ - # TODO: реализуйте функцию - return 0 + return (snowflake_id >> NODE_ID_SHIFT) & NODE_ID_MAX def decode_sequence_id(snowflake_id: int) -> int: @@ -78,8 +78,7 @@ def decode_sequence_id(snowflake_id: int) -> int: The per-millisecond sequence counter packed into ``snowflake_id``, in the range ``[0, SEQUENCE_ID_MAX]``. """ - # TODO: реализуйте функцию - return 0 + return (snowflake_id >> 0) & SEQUENCE_ID_MAX def generate_snowflake_id( @@ -110,5 +109,25 @@ def generate_snowflake_id( timestamp field (roughly 69 years after ``epoch_ms``). In each of those cases an explanatory message is printed to stdout first. """ - # TODO: реализуйте функцию - return 0 + if not (0 <= node_id <= NODE_ID_MAX): + print(f"node_id must be in [0, {NODE_ID_MAX}], got {node_id}") + return None + + if not (0 <= sequence_id <= SEQUENCE_ID_MAX): + print(f"sequence_id must be in [0, {SEQUENCE_ID_MAX}], got {sequence_id}") + return None + + elapsed_ms = read_current_millis(epoch_ms) + if elapsed_ms > TIMESTAMP_MS_MAX: + print( + f"timestamp overflows: elapsed {elapsed_ms} ms exceeds \n\ + TIMESTAMP_MS_MAX ({TIMESTAMP_MS_MAX})" + ) + return None + + snowflake_id = ( + (elapsed_ms << TIMESTAMP_SHIFT) + | (node_id << NODE_ID_SHIFT) + | (sequence_id << 0) + ) + return snowflake_id From 32888fc042e095446810c3573c99647614d9b8e1 Mon Sep 17 00:00:00 2001 From: Andrey Rudakov Date: Thu, 1 Oct 2026 22:39:17 +0300 Subject: [PATCH 02/10] Completed task 2 --- src/part2/cart.py | 71 +++++++++++++++++++++++++++++++++++++++----- src/part2/crud.py | 58 ++++++++++++++++++++++++++++-------- src/part2/storage.py | 12 ++++---- src/part2/utils.py | 10 +++---- 4 files changed, 119 insertions(+), 32 deletions(-) diff --git a/src/part2/cart.py b/src/part2/cart.py index 063f9aea..f915a397 100644 --- a/src/part2/cart.py +++ b/src/part2/cart.py @@ -11,8 +11,8 @@ from typing import Final -from .crud import read_product, update_product # noqa: F401 -from .storage import ( # noqa: F401 +from .crud import read_product, update_product +from .storage import ( NAME_INDEX, PRICE_INDEX, QUANTITY_INDEX, @@ -22,9 +22,15 @@ type CartLine = tuple[int, int] -# TODO: задайте позиции полей внутри кортежа CartLine LINE_PRODUCT_ID_INDEX: Final = 0 -LINE_QUANTITY_INDEX: Final = 0 +LINE_QUANTITY_INDEX: Final = 1 + + +def find_cart_line(cart: list[CartLine], product_id: int) -> CartLine | None: + for line in cart: + if line[LINE_PRODUCT_ID_INDEX] == product_id: + return line + return None def add_to_cart( @@ -53,8 +59,30 @@ def add_to_cart( The cart line for ``product_id`` after the addition, or ``None`` when the product is unknown or the store cannot cover the request. """ - # TODO: реализуйте функцию - return (0, 0) + product = read_product(storage, product_id) + if not product: + return None + if product[QUANTITY_INDEX] < quantity: + print( + f"not enough stock for product {product_id}: {product[QUANTITY_INDEX]} available, {quantity} requested" + ) + return None + update_product( + storage, + product_id, + (product[NAME_INDEX], product[PRICE_INDEX], product[QUANTITY_INDEX] - quantity), + ) + + line = find_cart_line(cart, product_id) + if line: + cart.remove(line) + updated_line = (product_id, line[LINE_QUANTITY_INDEX] + quantity) + cart.append(updated_line) + return updated_line + else: + new_line = (product_id, quantity) + cart.append(new_line) + return new_line def remove_from_cart( @@ -85,5 +113,32 @@ def remove_from_cart( zero means the line was dropped), or ``None`` when the cart has no line for the product or holds too few units. """ - # TODO: реализуйте функцию - return (0, 0) + line = find_cart_line(cart, product_id) + if not line: + print(f"product {product_id} is not in the cart") + return None + + if line[LINE_QUANTITY_INDEX] < quantity: + print( + f"cart holds only {line[LINE_QUANTITY_INDEX]} unit(s) of product {product_id}, cannot remove {quantity}" + ) + return None + + product = read_product(storage, product_id) + if not product: + print("read_product") + return None + + update_product( + storage, + product_id, + (product[NAME_INDEX], product[PRICE_INDEX], product[QUANTITY_INDEX] + quantity), + ) + + cart.remove(line) + if line[LINE_QUANTITY_INDEX] - quantity == 0: + return (product_id, 0) + + updated_line = (product_id, line[LINE_QUANTITY_INDEX] - quantity) + cart.append(updated_line) + return updated_line diff --git a/src/part2/crud.py b/src/part2/crud.py index d026cbcb..181f2c63 100644 --- a/src/part2/crud.py +++ b/src/part2/crud.py @@ -14,13 +14,15 @@ from decimal import Decimal -from .storage import ( # noqa: F401 +from .storage import ( NAME_INDEX, + PRICE_INDEX, PRODUCT_ID_INDEX, PRODUCT_ID_MIN, + QUANTITY_INDEX, Product, ) -from .utils import normalize_price # noqa: F401 +from .utils import normalize_price def generate_product_id(storage: list[Product]) -> int: @@ -34,8 +36,9 @@ def generate_product_id(storage: list[Product]) -> int: :data:`~src.part2.storage.PRODUCT_ID_MIN` when ``storage`` is empty. """ - # TODO: реализуйте функцию - return 0 + if not storage: + return PRODUCT_ID_MIN + return max(product[PRODUCT_ID_INDEX] for product in storage) + 1 def create_product( @@ -56,8 +59,17 @@ def create_product( ``storage`` is left unchanged and a message naming the clashing name is printed. """ - # TODO: реализуйте функцию - return 0 + name, price, quantity = fields + + for product in storage: + if product[NAME_INDEX] == name: + print(f"product name {name} is already taken") + return None + + product_id = generate_product_id(storage) + price = normalize_price(price) + storage.append((product_id, name, price, quantity)) + return product_id def read_product(storage: list[Product], product_id: int) -> Product | None: @@ -72,8 +84,16 @@ def read_product(storage: list[Product], product_id: int) -> Product | None: ``None`` when no product carries that identifier (a message is printed in that case). """ - # TODO: реализуйте функцию - return (0, "", Decimal(0), 0) + for product in storage: + if product[PRODUCT_ID_INDEX] == product_id: + return ( + product[PRODUCT_ID_INDEX], + product[NAME_INDEX], + product[PRICE_INDEX], + product[QUANTITY_INDEX], + ) + print(f"no product with id {product_id}") + return None def update_product( @@ -99,8 +119,18 @@ def update_product( ``None`` when no product carries that identifier (``storage`` is left unchanged and a message is printed). """ - # TODO: реализуйте функцию - return (0, "", Decimal(0), 0) + for ind, product in enumerate(storage): + if product[PRODUCT_ID_INDEX] == product_id: + updated_product = ( + product_id, + fields[0], + normalize_price(fields[1]), + fields[2], + ) + storage[ind] = updated_product + return storage[ind] + print(f"no product with id {product_id}") + return None def delete_product(storage: list[Product], product_id: int) -> int | None: @@ -116,5 +146,9 @@ def delete_product(storage: list[Product], product_id: int) -> int | None: product carried that identifier (``storage`` is left unchanged and a message is printed). """ - # TODO: реализуйте функцию - return 0 + for product in storage: + if product[PRODUCT_ID_INDEX] == product_id: + storage.remove(product) + return product_id + print(f"no product with id {product_id}") + return None diff --git a/src/part2/storage.py b/src/part2/storage.py index b63d5fc7..74ca50e5 100644 --- a/src/part2/storage.py +++ b/src/part2/storage.py @@ -24,11 +24,11 @@ type Product = tuple[int, str, Decimal, int] -# TODO: задайте позиции полей внутри кортежа Product + PRODUCT_ID_INDEX: Final = 0 -NAME_INDEX: Final = 0 -PRICE_INDEX: Final = 0 -QUANTITY_INDEX: Final = 0 +NAME_INDEX: Final = 1 +PRICE_INDEX: Final = 2 +QUANTITY_INDEX: Final = 3 + -# TODO: задайте идентификатор первого товара в пустом хранилище -PRODUCT_ID_MIN: Final[int] = 0 +PRODUCT_ID_MIN: Final[int] = 1 diff --git a/src/part2/utils.py b/src/part2/utils.py index ec0348d3..22f837a0 100644 --- a/src/part2/utils.py +++ b/src/part2/utils.py @@ -6,13 +6,12 @@ currency values free of binary floating-point error. """ -from decimal import ROUND_HALF_UP, Decimal # noqa: F401 +from decimal import ROUND_HALF_UP, Decimal from typing import Final -# TODO: задайте число знаков после запятой и шаг квантования -PRICE_PRECISION: Final[int] = 0 -PRICE_STEP: Final = Decimal(0) +PRICE_PRECISION: Final[int] = 2 +PRICE_STEP: Final = Decimal(1).scaleb(-PRICE_PRECISION) def normalize_price(price: Decimal) -> Decimal: @@ -25,5 +24,4 @@ def normalize_price(price: Decimal) -> Decimal: ``price`` quantised to :data:`PRICE_PRECISION` fractional digits, with halves rounded up. """ - # TODO: реализуйте функцию - return Decimal(0) + return price.quantize(PRICE_STEP, ROUND_HALF_UP) From 20f98de15527dc31b8d5f7136a38261ff461a7f8 Mon Sep 17 00:00:00 2001 From: Andrey Rudakov Date: Fri, 9 Oct 2026 00:16:44 +0300 Subject: [PATCH 03/10] Solve task 3 --- src/part3/crud.py | 72 +++++++++++++++++++++++++++++++------ src/part3/run_admin.py | 80 +++++++++++++++++++++++++++++++++++++----- src/part3/storage.py | 13 ++++--- src/part3/utils.py | 56 ++++++++++++++++++----------- 4 files changed, 174 insertions(+), 47 deletions(-) diff --git a/src/part3/crud.py b/src/part3/crud.py index 68811d7e..314d7dff 100644 --- a/src/part3/crud.py +++ b/src/part3/crud.py @@ -20,13 +20,15 @@ from decimal import Decimal -from .storage import ( # noqa: F401 +from .storage import ( NAME_INDEX, + PRICE_INDEX, PRODUCT_ID_INDEX, PRODUCT_ID_MIN, + QUANTITY_INDEX, Product, ) -from .utils import normalize_price, normalize_product_name # noqa: F401 +from .utils import normalize_price, normalize_product_name def generate_product_id(storage: list[Product]) -> int: @@ -40,8 +42,9 @@ def generate_product_id(storage: list[Product]) -> int: :data:`~src.part3.storage.PRODUCT_ID_MIN` when ``storage`` is empty. """ - # TODO: реализуйте функцию (используйте своё решение части 2) - return 0 + if not storage: + return PRODUCT_ID_MIN + return max(product[PRODUCT_ID_INDEX] for product in storage) + 1 def create_product( @@ -65,7 +68,22 @@ def create_product( is left unchanged and an explanatory message is printed. """ # TODO: реализуйте функцию - return 0 + raw_name, price, quantity = fields + name = normalize_product_name(raw_name) + + if not name: + print("product name must not be blank") + return None + + for product in storage: + if product[NAME_INDEX] == name: + print(f"product name {name} is already taken") + return None + + product_id = generate_product_id(storage) + price = normalize_price(price) + storage.append((product_id, name, price, quantity)) + return product_id def read_product(storage: list[Product], product_id: int) -> Product | None: @@ -80,8 +98,16 @@ def read_product(storage: list[Product], product_id: int) -> Product | None: ``None`` when no product carries that identifier (a message is printed in that case). """ - # TODO: реализуйте функцию (используйте своё решение части 2) - return (0, "", Decimal(0), 0) + for product in storage: + if product[PRODUCT_ID_INDEX] == product_id: + return ( + product[PRODUCT_ID_INDEX], + product[NAME_INDEX], + product[PRICE_INDEX], + product[QUANTITY_INDEX], + ) + print(f"no product with id {product_id}") + return None def update_product( @@ -110,8 +136,28 @@ def update_product( unchanged and an explanatory message is printed. Renaming a product to its own current name is allowed. """ - # TODO: реализуйте функцию - return (0, "", Decimal(0), 0) + raw_name, price, quantity = fields + name = normalize_product_name(raw_name) + price = normalize_price(price) + + target_index: int | None = None + for index, product in enumerate(storage): + if product[PRODUCT_ID_INDEX] == product_id: + target_index = index + break + + if target_index is None: + print(f"no product with id {product_id}") + return None + + for product in storage: + if product[NAME_INDEX] == name and product[PRODUCT_ID_INDEX] != product_id: + print(f"product name '{name}' is already taken") + return None + + updated = (product_id, name, price, quantity) + storage[target_index] = updated + return updated def delete_product(storage: list[Product], product_id: int) -> int | None: @@ -127,5 +173,9 @@ def delete_product(storage: list[Product], product_id: int) -> int | None: product carried that identifier (``storage`` is left unchanged and a message is printed). """ - # TODO: реализуйте функцию (используйте своё решение части 2) - return 0 + for product in storage: + if product[PRODUCT_ID_INDEX] == product_id: + storage.remove(product) + return product_id + print(f"no product with id {product_id}") + return None diff --git a/src/part3/run_admin.py b/src/part3/run_admin.py index c5feeb0b..81b8b543 100644 --- a/src/part3/run_admin.py +++ b/src/part3/run_admin.py @@ -29,22 +29,33 @@ it. """ -from decimal import Decimal, InvalidOperation # noqa: F401 +from decimal import Decimal, InvalidOperation from typing import Final -from .crud import ( # noqa: F401 +from .crud import ( create_product, delete_product, read_product, update_product, ) from .storage import Product -from .utils import get_storage_str_representation # noqa: F401 +from .utils import get_storage_str_representation # TODO: задайте приглашение и текст справки -PROMPT: Final[str] = "" -HELP_TEXT: Final[str] = "" +PROMPT: Final[str] = "admin> " +HELP_TEXT: Final[str] = """Available commands: + help show this message + exit leave the console + show print the whole store as a table + create add a product, print its new id + read print the product with that id + update overwrite that product's fields + delete remove the product with that id + +For create and update the price and quantity are the last two words of the +line; everything before them is the product name, so it may contain spaces +(for example "Gibson SG Junior") and needs no quoting.""" def show_help() -> None: @@ -54,7 +65,7 @@ def show_help() -> None: is: a heading, one line per command with a short description, and a note on how multi-word names are parsed. """ - # TODO: реализуйте функцию + print(HELP_TEXT) def print_result(result: object) -> None: @@ -65,7 +76,8 @@ def print_result(result: object) -> None: operation already reported its own failure, so nothing is printed in that case. """ - # TODO: реализуйте функцию + if result is not None: + print(result) def run_command(storage: list[Product], line: str) -> bool: @@ -88,8 +100,58 @@ def run_command(storage: list[Product], line: str) -> bool: decimal.InvalidOperation: If the price argument of ``create`` or ``update`` does not parse as a decimal number. """ - # TODO: реализуйте функцию - return False + words = line.split() + + if not words: + print(f"'{line}' is not a command") + return True + + command = words[0] + + match command: + case "help" if len(words) == 1: + show_help() + return True + + case "exit" if len(words) == 1: + return False + + case "show" if len(words) == 1: + print(get_storage_str_representation(storage)) + return True + + case "create" if len(words) >= 4: + name = " ".join(words[1:-2]) + price = Decimal(words[-2]) + quantity = int(words[-1]) + result = create_product(storage, (name, price, quantity)) + print_result(result) + return True + + case "read" if len(words) == 2: + product_id = int(words[1]) + result = read_product(storage, product_id) + print_result(result) + return True + + case "update" if len(words) >= 5: + product_id = int(words[1]) + name = " ".join(words[2:-2]) + price = Decimal(words[-2]) + quantity = int(words[-1]) + result = update_product(storage, product_id, (name, price, quantity)) + print_result(result) + return True + + case "delete" if len(words) == 2: + product_id = int(words[1]) + result = delete_product(storage, product_id) + print_result(result) + return True + + case _: + print(f"'{line}' is not a command") + return True def main() -> None: diff --git a/src/part3/storage.py b/src/part3/storage.py index c5e34be5..319eab75 100644 --- a/src/part3/storage.py +++ b/src/part3/storage.py @@ -24,12 +24,11 @@ type Product = tuple[int, str, Decimal, int] -# TODO: задайте позиции полей внутри кортежа Product (используйте своё решение -# части 2) + PRODUCT_ID_INDEX: Final = 0 -NAME_INDEX: Final = 0 -PRICE_INDEX: Final = 0 -QUANTITY_INDEX: Final = 0 +NAME_INDEX: Final = 1 +PRICE_INDEX: Final = 2 +QUANTITY_INDEX: Final = 3 + -# TODO: задайте идентификатор первого товара в пустом хранилище -PRODUCT_ID_MIN: Final[int] = 0 +PRODUCT_ID_MIN: Final[int] = 1 diff --git a/src/part3/utils.py b/src/part3/utils.py index 318ded0b..9764c47f 100644 --- a/src/part3/utils.py +++ b/src/part3/utils.py @@ -18,24 +18,17 @@ the longest value it holds in that particular call. """ -from decimal import ROUND_HALF_UP, Decimal # noqa: F401 +from decimal import ROUND_HALF_UP, Decimal +from re import sub from typing import Final -from .storage import Product +from .storage import NAME_INDEX, PRICE_INDEX, PRODUCT_ID_INDEX, QUANTITY_INDEX, Product -# Number of fractional digits every stored price is rounded to. -# Quantisation step derived from PRICE_PRECISION, e.g. Decimal("0.01"). -# TODO: задайте число знаков после запятой и шаг квантования (используйте своё -# решение части 2) -PRICE_PRECISION: Final[int] = 0 -PRICE_STEP: Final = Decimal(0) +PRICE_PRECISION: Final[int] = 2 +PRICE_STEP: Final = Decimal(1).scaleb(-PRICE_PRECISION) -# Column headers of the table produced by get_storage_str_representation, -# left to right. The width of each column is not fixed here -- it is -# measured per call from the data (see the function). -# TODO: задайте заголовки столбцов таблицы -TABLE_HEADERS: Final[tuple[str, ...]] = () +TABLE_HEADERS: Final[tuple[str, ...]] = ("ID", "name", "price", "quantity") def normalize_price(price: Decimal) -> Decimal: @@ -48,8 +41,7 @@ def normalize_price(price: Decimal) -> Decimal: ``price`` quantised to :data:`PRICE_PRECISION` fractional digits, with halves rounded up. """ - # TODO: реализуйте функцию (используйте своё решение части 2) - return Decimal(0) + return price.quantize(PRICE_STEP, ROUND_HALF_UP) def normalize_product_name(name: str) -> str: @@ -66,11 +58,16 @@ def normalize_product_name(name: str) -> str: The result is an empty string when ``name`` holds nothing but whitespace. """ - # TODO: реализуйте функцию - return "" + return sub(r"\s+", " ", name.strip()).lower() -# TODO: при необходимости добавьте свои вспомогательные функции +def format_row(values: list[str] | tuple[str, ...], widths: list[int]) -> str: + cells = [values[i].ljust(widths[i]) for i in range(len(widths))] + return "| " + " | ".join(cells) + " |" + + +def separator(widths: list[int]) -> str: + return "|" + "|".join(["-" * (w + 2) for w in widths]) + "|" def get_storage_str_representation(storage: list[Product]) -> str: @@ -91,5 +88,24 @@ def get_storage_str_representation(storage: list[Product]) -> str: is empty only the header and separator rows are returned, sized to the header labels. """ - # TODO: реализуйте функцию - return "" + rows: list[list[str]] = [] + for product in storage: + rows.append( + [ + str(product[PRODUCT_ID_INDEX]), + str(product[NAME_INDEX]), + str(product[PRICE_INDEX]), + str(product[QUANTITY_INDEX]), + ] + ) + + widths = [len(h) for h in TABLE_HEADERS] + for row in rows: + for i, value in enumerate(row): + widths[i] = max(widths[i], len(value)) + + lines = [format_row(TABLE_HEADERS, widths), separator(widths)] + for row in rows: + lines.append(format_row(row, widths)) + + return "\n".join(lines) From 34ab31119960a95f80725331b79b9eda799fd1b5 Mon Sep 17 00:00:00 2001 From: Andrey Rudakov Date: Fri, 9 Oct 2026 00:34:04 +0300 Subject: [PATCH 04/10] Cleaned up --- src/part3/crud.py | 1 - src/part3/run_admin.py | 5 +++-- 2 files changed, 3 insertions(+), 3 deletions(-) diff --git a/src/part3/crud.py b/src/part3/crud.py index 314d7dff..9abe5eb6 100644 --- a/src/part3/crud.py +++ b/src/part3/crud.py @@ -67,7 +67,6 @@ def create_product( normalised name already exists. In the ``None`` case ``storage`` is left unchanged and an explanatory message is printed. """ - # TODO: реализуйте функцию raw_name, price, quantity = fields name = normalize_product_name(raw_name) diff --git a/src/part3/run_admin.py b/src/part3/run_admin.py index 81b8b543..85fa1641 100644 --- a/src/part3/run_admin.py +++ b/src/part3/run_admin.py @@ -42,7 +42,6 @@ from .utils import get_storage_str_representation -# TODO: задайте приглашение и текст справки PROMPT: Final[str] = "admin> " HELP_TEXT: Final[str] = """Available commands: help show this message @@ -124,7 +123,9 @@ def run_command(storage: list[Product], line: str) -> bool: name = " ".join(words[1:-2]) price = Decimal(words[-2]) quantity = int(words[-1]) - result = create_product(storage, (name, price, quantity)) + result: int | Product | None = create_product( + storage, (name, price, quantity) + ) print_result(result) return True From 2cae6c946bef42b525472f0092d1a2e427540cac Mon Sep 17 00:00:00 2001 From: Andrey Rudakov Date: Thu, 29 Oct 2026 00:38:20 +0300 Subject: [PATCH 05/10] Comleted part 4 --- src/part4/cart.py | 59 +++++++++++++++++++++++---- src/part4/crud.py | 70 ++++++++++++++++++++++++++------ src/part4/run_admin.py | 92 +++++++++++++++++++++++++++++++++++++----- src/part4/storage.py | 7 ++-- src/part4/utils.py | 65 ++++++++++++++++------------- 5 files changed, 228 insertions(+), 65 deletions(-) diff --git a/src/part4/cart.py b/src/part4/cart.py index aed9bb72..3003c976 100644 --- a/src/part4/cart.py +++ b/src/part4/cart.py @@ -9,10 +9,8 @@ an explanatory message to stdout and returns ``None``. """ -from .storage import Product - - -# TODO: при необходимости добавьте свои вспомогательные функции +from .crud import read_product, update_product +from .storage import QUANTITY_KEY, Product def add_to_cart( @@ -46,8 +44,29 @@ def add_to_cart( ``None`` when the product is unknown or the store cannot cover the request. """ - # TODO: реализуйте функцию - return 0 + product: Product | None = read_product(storage, product_id) + if product is None: + print(f"no product with id {product_id}") + return None + + if product[QUANTITY_KEY] < quantity: + print( + f"not enough stock for product {product_id}: {product[QUANTITY_KEY]} available, {quantity} requested" + ) + return None + + update_product( + storage, + product_names, + product_id, + {QUANTITY_KEY: product[QUANTITY_KEY] - quantity}, + ) + + if product_id in cart: + cart[product_id] += quantity + else: + cart[product_id] = quantity + return cart[product_id] def remove_from_cart( @@ -83,5 +102,29 @@ def remove_from_cart( (zero means the product was dropped from the cart), or ``None`` when the cart does not hold the product or holds too few units. """ - # TODO: реализуйте функцию - return 0 + if product_id not in cart: + print(f"product {product_id} is not in the cart") + return None + + if cart[product_id] < quantity: + print( + f"cart holds only {cart[product_id]} unit(s) of product {product_id}, cannot remove {quantity}" + ) + return None + + if product_id not in storage: + print(f"no product with id {product_id}") + return None + + update_product( + storage, + product_names, + product_id, + {QUANTITY_KEY: storage[product_id][QUANTITY_KEY] + quantity}, + ) + + cart[product_id] -= quantity + if cart[product_id] == 0: + del cart[product_id] + return 0 + return cart[product_id] diff --git a/src/part4/crud.py b/src/part4/crud.py index 471eff00..96305ef2 100644 --- a/src/part4/crud.py +++ b/src/part4/crud.py @@ -23,16 +23,16 @@ than a scan over ``storage.values()``. """ -import uuid # noqa: F401 +import uuid from typing import Any -from .storage import ( # noqa: F401 +from .storage import ( NAME_KEY, PRICE_KEY, QUANTITY_KEY, Product, ) -from .utils import normalize_price, normalize_product_name # noqa: F401 +from .utils import normalize_price, normalize_product_name def generate_product_id() -> str: @@ -41,8 +41,7 @@ def generate_product_id() -> str: Returns: A freshly generated UUID, stringified. """ - # TODO: реализуйте функцию - return "" + return str(uuid.uuid4()) def create_product( @@ -73,8 +72,23 @@ def create_product( and ``product_names`` are left unchanged and an explanatory message is printed. """ - # TODO: реализуйте функцию - return "" + name: str = normalize_product_name(fields[NAME_KEY]) + if not name: + print("product name must not be blank") + return None + + if name in product_names: + print(f"product name '{name}' is already taken") + return None + + ID: str = generate_product_id() + storage[ID] = { + NAME_KEY: name, + PRICE_KEY: normalize_price(fields[PRICE_KEY]), + QUANTITY_KEY: fields[QUANTITY_KEY], + } + product_names.add(name) + return ID def read_product(storage: dict[str, Product], product_id: str) -> Product | None: @@ -88,8 +102,11 @@ def read_product(storage: dict[str, Product], product_id: str) -> Product | None The matching product record, or ``None`` when no product carries that identifier (a message is printed in that case). """ - # TODO: реализуйте функцию - return {} + for ID in storage: + if ID == product_id: + return storage[product_id] + print(f"no product with id {product_id}") + return None def update_product( @@ -129,8 +146,31 @@ def update_product( and an explanatory message is printed. Renaming a product to its own current name is allowed. """ - # TODO: реализуйте функцию - return {} + if product_id not in storage: + print(f"no product with id {product_id}") + return None + for key in fields: + if key == NAME_KEY: + fields[NAME_KEY] = normalize_product_name(fields[NAME_KEY]) + name = fields[NAME_KEY] + if not name: + print("product name must not be blank") + return None + old_name = storage[product_id][NAME_KEY] + if name != old_name: + if name in product_names: + print(f"product name '{name}' is already taken") + return None + product_names.remove(old_name) + product_names.add(name) + storage[product_id][NAME_KEY] = name + + elif key == PRICE_KEY: + storage[product_id][PRICE_KEY] = normalize_price(fields[PRICE_KEY]) + + elif key == QUANTITY_KEY: + storage[product_id][QUANTITY_KEY] = fields[QUANTITY_KEY] + return storage[product_id] def delete_product( @@ -153,5 +193,9 @@ def delete_product( product carried that identifier (``storage`` and ``product_names`` are left unchanged and a message is printed). """ - # TODO: реализуйте функцию - return "" + result: Product | None = storage.pop(product_id, None) + if result is None: + print(f"no product with id {product_id}") + return None + product_names.remove(result[NAME_KEY]) + return product_id diff --git a/src/part4/run_admin.py b/src/part4/run_admin.py index 2247b29b..8ef409b3 100644 --- a/src/part4/run_admin.py +++ b/src/part4/run_admin.py @@ -28,22 +28,32 @@ is left untouched and the loop keeps running; only ``exit`` stops it. """ -from decimal import Decimal, InvalidOperation # noqa: F401 +from decimal import Decimal, InvalidOperation from typing import Final -from .crud import ( # noqa: F401 +from .crud import ( create_product, delete_product, read_product, update_product, ) -from .storage import NAME_KEY, PRICE_KEY, QUANTITY_KEY, Product # noqa: F401 -from .utils import get_storage_str_representation # noqa: F401 +from .storage import NAME_KEY, PRICE_KEY, QUANTITY_KEY, Product +from .utils import get_storage_str_representation -# TODO: задайте приглашение и текст справки (используйте своё решение части 3) -PROMPT: Final[str] = "" -HELP_TEXT: Final[str] = "" +PROMPT: Final[str] = "admin> " +HELP_TEXT: Final[str] = """Available commands: + help show this message + exit leave the console + show print the whole store as a table + create add a product, print its new id + read print the product with that id + update overwrite that product's fields + delete remove the product with that id + +For create and update the price and quantity are the last two words of the +line; everything before them is the product name, so it may contain spaces +(for example "Gibson SG Junior") and needs no quoting.""" def show_help() -> None: @@ -53,7 +63,7 @@ def show_help() -> None: is: a heading, one line per command with a short description, and a note on how multi-word names are parsed. """ - # TODO: реализуйте функцию (используйте своё решение части 3) + print(HELP_TEXT) def print_result(result: object) -> None: @@ -64,7 +74,8 @@ def print_result(result: object) -> None: operation already reported its own failure, so nothing is printed in that case. """ - # TODO: реализуйте функцию (используйте своё решение части 3) + if result is not None: + print(result) def run_command( @@ -91,8 +102,67 @@ def run_command( decimal.InvalidOperation: If the price argument of ``create`` or ``update`` does not parse as a decimal number. """ - # TODO: реализуйте функцию - return False + words = line.split() + + if not words: + print(f"'{line}' is not a command") + return True + + command = words[0] + + match command: + case "help" if len(words) == 1: + show_help() + return True + + case "exit" if len(words) == 1: + return False + + case "show" if len(words) == 1: + print(get_storage_str_representation(storage)) + return True + + case "create" if len(words) >= 4: + name = " ".join(words[1:-2]) + price = Decimal(words[-2]) + quantity = int(words[-1]) + result: str | Product | None = create_product( + storage, + product_names, + {NAME_KEY: name, PRICE_KEY: price, QUANTITY_KEY: quantity}, + ) + print_result(result) + return True + + case "read" if len(words) == 2: + product_id = words[1] + result = read_product(storage, product_id) + print_result(result) + return True + + case "update" if len(words) >= 5: + product_id = words[1] + name = " ".join(words[2:-2]) + price = Decimal(words[-2]) + quantity = int(words[-1]) + result = update_product( + storage, + product_names, + product_id, + {NAME_KEY: name, PRICE_KEY: price, QUANTITY_KEY: quantity}, + ) + print_result(result) + return True + + case "delete" if len(words) == 2: + product_id = words[1] + result = delete_product(storage, product_names, product_id) + print_result(result) + return True + + case _: + print(f"'{line}' is not a command") + return True def main() -> None: diff --git a/src/part4/storage.py b/src/part4/storage.py index 9acedf07..015109fe 100644 --- a/src/part4/storage.py +++ b/src/part4/storage.py @@ -39,7 +39,6 @@ type Product = dict[str, Any] # Name of each field inside a Product record. -# TODO: задайте имена полей записи -NAME_KEY: Final = "" -PRICE_KEY: Final = "" -QUANTITY_KEY: Final = "" +NAME_KEY: Final[str] = "name" +PRICE_KEY: Final[str] = "price" +QUANTITY_KEY: Final[str] = "quantity" diff --git a/src/part4/utils.py b/src/part4/utils.py index d2a940ea..a110409c 100644 --- a/src/part4/utils.py +++ b/src/part4/utils.py @@ -1,4 +1,4 @@ -"""Standalone helpers shared by the part4 storage and CRUD modules. +"""Standalone helpers shared by the part3 storage and CRUD modules. Normalisation: @@ -18,29 +18,17 @@ the longest value it holds in that particular call. """ -from decimal import ROUND_HALF_UP, Decimal # noqa: F401 +from decimal import ROUND_HALF_UP, Decimal +from re import sub from typing import Final -from .storage import ( # noqa: F401 - NAME_KEY, - PRICE_KEY, - QUANTITY_KEY, - Product, -) +from .storage import NAME_KEY, PRICE_KEY, QUANTITY_KEY, Product -# Number of fractional digits every stored price is rounded to. -# Quantisation step derived from PRICE_PRECISION, e.g. Decimal("0.01"). -# TODO: задайте число знаков после запятой и шаг квантования (используйте своё -# решение части 3) -PRICE_PRECISION: Final[int] = 0 -PRICE_STEP: Final = Decimal(0) +PRICE_PRECISION: Final[int] = 2 +PRICE_STEP: Final = Decimal(1).scaleb(-PRICE_PRECISION) -# Column headers of the table produced by get_storage_str_representation, -# left to right. The width of each column is not fixed here -- it is -# measured per call from the data (see the function). -# TODO: задайте заголовки столбцов таблицы (используйте своё решение части 3) -TABLE_HEADERS: Final[tuple[str, ...]] = () +TABLE_HEADERS: Final[tuple[str, ...]] = ("ID", "name", "price", "quantity") def normalize_price(price: Decimal) -> Decimal: @@ -53,8 +41,7 @@ def normalize_price(price: Decimal) -> Decimal: ``price`` quantised to :data:`PRICE_PRECISION` fractional digits, with halves rounded up. """ - # TODO: реализуйте функцию (используйте своё решение части 3) - return Decimal(0) + return price.quantize(PRICE_STEP, ROUND_HALF_UP) def normalize_product_name(name: str) -> str: @@ -71,11 +58,16 @@ def normalize_product_name(name: str) -> str: The result is an empty string when ``name`` holds nothing but whitespace. """ - # TODO: реализуйте функцию (используйте своё решение части 3) - return "" + return sub(r"\s+", " ", name.strip()).lower() -# TODO: при необходимости добавьте свои вспомогательные функции +def format_row(values: list[str] | tuple[str, ...], widths: list[int]) -> str: + cells = [values[i].ljust(widths[i]) for i in range(len(widths))] + return "| " + " | ".join(cells) + " |" + + +def separator(widths: list[int]) -> str: + return "|" + "|".join(["-" * (w + 2) for w in widths]) + "|" def get_storage_str_representation(storage: dict[str, Product]) -> str: @@ -92,9 +84,24 @@ def get_storage_str_representation(storage: dict[str, Product]) -> str: Returns: A multi-line string: a header row, a dashed separator row, then - one row per product in ``storage``, in insertion order. When - ``storage`` is empty only the header and separator rows are - returned, sized to the header labels. + one row per product in ``storage`` in list order. When ``storage`` + is empty only the header and separator rows are returned, sized to + the header labels. """ - # TODO: реализуйте функцию (используйте своё решение части 3) - return "" + rows: list[list[str]] = [] + for ID, value in storage.items(): + product: Product = value + rows.append( + [ID, product[NAME_KEY], str(product[PRICE_KEY]), str(product[QUANTITY_KEY])] + ) + + widths: list[int] = [len(h) for h in TABLE_HEADERS] + for row in rows: + for i in range(len(row)): + widths[i] = max(widths[i], len(row[i])) + + lines = [format_row(TABLE_HEADERS, widths), separator(widths)] + for row in rows: + lines.append(format_row(row, widths)) + + return "\n".join(lines) From 4fba5a97a8842d385ef79fb139fc9929a9236a5f Mon Sep 17 00:00:00 2001 From: Andrey Rudakov Date: Thu, 29 Oct 2026 15:31:33 +0300 Subject: [PATCH 06/10] Comments were corrected --- src/part4/utils.py | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-) diff --git a/src/part4/utils.py b/src/part4/utils.py index a110409c..6d74dd6b 100644 --- a/src/part4/utils.py +++ b/src/part4/utils.py @@ -1,4 +1,4 @@ -"""Standalone helpers shared by the part3 storage and CRUD modules. +"""Standalone helpers shared by the part4 storage and CRUD modules. Normalisation: @@ -25,9 +25,14 @@ from .storage import NAME_KEY, PRICE_KEY, QUANTITY_KEY, Product +# Number of fractional digits every stored price is rounded to. +# Quantisation step derived from PRICE_PRECISION, e.g. Decimal("0.01"). PRICE_PRECISION: Final[int] = 2 PRICE_STEP: Final = Decimal(1).scaleb(-PRICE_PRECISION) +# Column headers of the table produced by get_storage_str_representation, +# left to right. The width of each column is not fixed here -- it is +# measured per call from the data (see the function). TABLE_HEADERS: Final[tuple[str, ...]] = ("ID", "name", "price", "quantity") @@ -84,9 +89,9 @@ def get_storage_str_representation(storage: dict[str, Product]) -> str: Returns: A multi-line string: a header row, a dashed separator row, then - one row per product in ``storage`` in list order. When ``storage`` - is empty only the header and separator rows are returned, sized to - the header labels. + one row per product in ``storage``, in insertion order. When + ``storage`` is empty only the header and separator rows are + returned, sized to the header labels. """ rows: list[list[str]] = [] for ID, value in storage.items(): From b8c3dae789844ba3fd8184d40d88bb7bcf012bf3 Mon Sep 17 00:00:00 2001 From: Andrey Rudakov Date: Thu, 29 Oct 2026 16:02:14 +0300 Subject: [PATCH 07/10] crud.update_product was corrected --- src/part4/crud.py | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/src/part4/crud.py b/src/part4/crud.py index 96305ef2..27f5b80b 100644 --- a/src/part4/crud.py +++ b/src/part4/crud.py @@ -166,7 +166,8 @@ def update_product( storage[product_id][NAME_KEY] = name elif key == PRICE_KEY: - storage[product_id][PRICE_KEY] = normalize_price(fields[PRICE_KEY]) + fields[PRICE_KEY] = normalize_price(fields[PRICE_KEY]) + storage[product_id][PRICE_KEY] = fields[PRICE_KEY] elif key == QUANTITY_KEY: storage[product_id][QUANTITY_KEY] = fields[QUANTITY_KEY] From 06d9d1057a474c40b85de247fc6bd5df53a6a5d8 Mon Sep 17 00:00:00 2001 From: Andrey Rudakov Date: Wed, 4 Nov 2026 01:22:40 +0300 Subject: [PATCH 08/10] bug fix bugs carried over from part 3 have been fixed --- src/part4/run_admin.py | 38 ++++++++++++++++++-------------------- 1 file changed, 18 insertions(+), 20 deletions(-) diff --git a/src/part4/run_admin.py b/src/part4/run_admin.py index 8ef409b3..802d1029 100644 --- a/src/part4/run_admin.py +++ b/src/part4/run_admin.py @@ -102,30 +102,28 @@ def run_command( decimal.InvalidOperation: If the price argument of ``create`` or ``update`` does not parse as a decimal number. """ - words = line.split() + command = line.split() - if not words: + if not command: print(f"'{line}' is not a command") return True - command = words[0] - match command: - case "help" if len(words) == 1: + case ["help"]: show_help() return True - case "exit" if len(words) == 1: + case ["exit"]: return False - case "show" if len(words) == 1: + case ["show"]: print(get_storage_str_representation(storage)) return True - case "create" if len(words) >= 4: - name = " ".join(words[1:-2]) - price = Decimal(words[-2]) - quantity = int(words[-1]) + case ["create", *name_parts, str_price, str_quantity]: + name = " ".join(name_parts) + price = Decimal(str_price) + quantity = int(str_quantity) result: str | Product | None = create_product( storage, product_names, @@ -134,17 +132,17 @@ def run_command( print_result(result) return True - case "read" if len(words) == 2: - product_id = words[1] + case ["read", id]: + product_id = id result = read_product(storage, product_id) print_result(result) return True - case "update" if len(words) >= 5: - product_id = words[1] - name = " ".join(words[2:-2]) - price = Decimal(words[-2]) - quantity = int(words[-1]) + case ["update", id, *name_parts, str_price, str_quantity]: + product_id = id + name = " ".join(name_parts) + price = Decimal(str_price) + quantity = int(str_quantity) result = update_product( storage, product_names, @@ -154,8 +152,8 @@ def run_command( print_result(result) return True - case "delete" if len(words) == 2: - product_id = words[1] + case ["delete", id]: + product_id = id result = delete_product(storage, product_names, product_id) print_result(result) return True From c9d18668ee5586cff25c08fe3508619507cc1728 Mon Sep 17 00:00:00 2001 From: Andrey Rudakov Date: Thu, 12 Nov 2026 15:23:17 +0300 Subject: [PATCH 09/10] Completed part 5 --- src/part5/cart.py | 64 ++++++++++++++++++++-- src/part5/constants.py | 25 +++++---- src/part5/crud.py | 117 ++++++++++++++++++++++++++++++---------- src/part5/decorators.py | 27 ++++++++-- src/part5/run_admin.py | 101 +++++++++++++++++++++++++++++++--- src/part5/snowflake.py | 74 +++++++++++++++++++------ src/part5/storage.py | 7 ++- src/part5/utils.py | 84 ++++++++++++++++++++++------- 8 files changed, 400 insertions(+), 99 deletions(-) diff --git a/src/part5/cart.py b/src/part5/cart.py index a2363b3a..e93634ad 100644 --- a/src/part5/cart.py +++ b/src/part5/cart.py @@ -9,7 +9,8 @@ an explanatory message to stdout and returns ``None``. """ -from .storage import Product +from .crud import read_product, update_product +from .storage import QUANTITY_KEY, Product # TODO: при необходимости добавьте свои вспомогательные функции @@ -47,8 +48,33 @@ def add_to_cart( ``None`` when the product is unknown or the store cannot cover the request. """ - # TODO: реализуйте функцию (используйте своё решение части 4) - return 0 + product: Product | None = read_product(storage, product_id) + if product is None: + print(f"no product with id {product_id}") + return None + + if product[QUANTITY_KEY] < quantity: + print( + f"not enough stock for product {product_id}: {product[QUANTITY_KEY]} available, {quantity} requested" + ) + return None + + if quantity < 0: + print("quantity must be non-negative") + return None + + update_product( + storage, + product_names, + product_id, + {QUANTITY_KEY: product[QUANTITY_KEY] - quantity}, + ) + + if product_id in cart: + cart[product_id] += quantity + else: + cart[product_id] = quantity + return cart[product_id] def remove_from_cart( @@ -84,5 +110,33 @@ def remove_from_cart( (zero means the product was dropped from the cart), or ``None`` when the cart does not hold the product or holds too few units. """ - # TODO: реализуйте функцию (используйте своё решение части 4) - return 0 + if product_id not in cart: + print(f"product {product_id} is not in the cart") + return None + + if quantity < 0: + print("quantity must be non-negative") + return None + + if cart[product_id] < quantity: + print( + f"cart holds only {cart[product_id]} unit(s) of product {product_id}, cannot remove {quantity}" + ) + return None + + if product_id not in storage: + print(f"no product with id {product_id}") + return None + + update_product( + storage, + product_names, + product_id, + {QUANTITY_KEY: storage[product_id][QUANTITY_KEY] + quantity}, + ) + + cart[product_id] -= quantity + if cart[product_id] == 0: + del cart[product_id] + return 0 + return cart[product_id] diff --git a/src/part5/constants.py b/src/part5/constants.py index 984671bb..c49f0781 100644 --- a/src/part5/constants.py +++ b/src/part5/constants.py @@ -15,23 +15,26 @@ from typing import Final -# TODO: замените заглушки (0) на корректные значения (используйте своё решение -# части 1). - # Twitter's original Snowflake epoch: 2010-11-04 01:42:54.657 UTC. -EPOCH_MS_DEFAULT: Final[int] = 0 +EPOCH_MS_DEFAULT: Final[int] = 1288834974657 # Node identifier used when the caller does not supply one. -NODE_ID_DEFAULT: Final[int] = 0 +NODE_ID_DEFAULT: Final[int] = 1 # Width of each field, in bits. -TIMESTAMP_BITS: Final[int] = 0 -NODE_ID_BITS: Final[int] = 0 -SEQUENCE_ID_BITS: Final[int] = 0 +TIMESTAMP_BITS: Final[int] = 41 +NODE_ID_BITS: Final[int] = 10 +SEQUENCE_ID_BITS: Final[int] = 12 # Largest value each field can hold. -TIMESTAMP_MS_MAX: Final[int] = 0 -NODE_ID_MAX: Final[int] = 0 -SEQUENCE_ID_MAX: Final[int] = 0 +TIMESTAMP_MS_MAX: Final[int] = (1 << TIMESTAMP_BITS) - 1 +NODE_ID_MAX: Final[int] = (1 << NODE_ID_BITS) - 1 +SEQUENCE_ID_MAX: Final[int] = (1 << SEQUENCE_ID_BITS) - 1 # Здесь можно добавить собственные вспомогательные константы +# (например, сдвиги полей при сборке идентификатора). + +# Shift amounts +SEQUENCE_ID_SHIFT: Final[int] = 0 +NODE_ID_SHIFT: Final[int] = SEQUENCE_ID_BITS +TIMESTAMP_SHIFT: Final[int] = SEQUENCE_ID_BITS + NODE_ID_BITS diff --git a/src/part5/crud.py b/src/part5/crud.py index 243b0528..32d8cd7d 100644 --- a/src/part5/crud.py +++ b/src/part5/crud.py @@ -36,22 +36,27 @@ """ from collections.abc import Callable +from decimal import Decimal from typing import Any, Final -from .decorators import Registry -from .storage import Product +from .decorators import Registry, collect_stats +from .snowflake import get_snowflake_id_generator +from .storage import NAME_KEY, PRICE_KEY, QUANTITY_KEY, Product +from .utils import normalize_price, normalize_product_name STATS_REGISTRY: Final[Registry] = {} -# TODO: задайте ключи операций в реестре, см. TASK.md -CREATE_KEY: Final[str] = "" -READ_KEY: Final[str] = "" -UPDATE_KEY: Final[str] = "" -DELETE_KEY: Final[str] = "" +CREATE_KEY: Final[str] = "create" +READ_KEY: Final[str] = "read" +UPDATE_KEY: Final[str] = "update" +DELETE_KEY: Final[str] = "delete" -# TODO: при необходимости заведите здесь общий генератор Snowflake-идентификаторов -# для generate_snowflake_id (см. TASK.md) +snowflake_id_generator: Final[Callable[[], int | None] | None] = ( + get_snowflake_id_generator() +) +# общий генератор Snowflake-идентификаторов +# для generate_snowflake_id def generate_snowflake_id() -> int | None: @@ -65,11 +70,12 @@ def generate_snowflake_id() -> int | None: :func:`~src.part5.snowflake.get_snowflake_id_generator` for the cases. """ - # TODO: реализуйте функцию - return 0 + if snowflake_id_generator is None: + return None + return snowflake_id_generator() -# TODO: оберните операцию декоратором collect_stats +@collect_stats(CREATE_KEY, STATS_REGISTRY) def create_product( storage: dict[int, Product], product_names: set[str], @@ -104,11 +110,28 @@ def create_product( ``product_names`` are left unchanged and an explanatory message is printed (for the last case, by ``generate_id`` itself). """ - # TODO: реализуйте функцию - return 0 - - -# TODO: оберните операцию декоратором collect_stats + name: str = normalize_product_name(fields[NAME_KEY]) + if not name: + print("product name must not be blank") + return None + + if name in product_names: + print(f"product name '{name}' is already taken") + return None + + id: int | None = generate_id() + if id is None: + return None + storage[id] = { + NAME_KEY: name, + PRICE_KEY: normalize_price(fields[PRICE_KEY]), + QUANTITY_KEY: fields[QUANTITY_KEY], + } + product_names.add(name) + return id + + +@collect_stats(READ_KEY, STATS_REGISTRY) def read_product(storage: dict[int, Product], product_id: int) -> Product | None: """Return the product stored under ``product_id``. @@ -120,11 +143,13 @@ def read_product(storage: dict[int, Product], product_id: int) -> Product | None The matching product record, or ``None`` when no product carries that identifier (a message is printed in that case). """ - # TODO: реализуйте функцию (используйте своё решение части 4) - return {} + product = storage.get(product_id) + if product is None: + print(f"no product with id {product_id}") + return product -# TODO: оберните операцию декоратором collect_stats +@collect_stats(UPDATE_KEY, STATS_REGISTRY) def update_product( storage: dict[int, Product], product_names: set[str], @@ -151,8 +176,6 @@ def update_product( :data:`~src.part5.storage.QUANTITY_KEY`) holding the new values. ``price`` is a :class:`~decimal.Decimal` amount and is rounded to the stored money precision before it is saved. - Mutated in place: a ``name`` or ``price`` value present in - ``fields`` is overwritten with its normalised form. Returns: The updated product record, or ``None`` when ``name`` is present @@ -162,11 +185,43 @@ def update_product( and an explanatory message is printed. Renaming a product to its own current name is allowed. """ - # TODO: реализуйте функцию (используйте своё решение части 4) - return {} - - -# TODO: оберните операцию декоратором collect_stats + if product_id not in storage: + print(f"no product with id {product_id}") + return None + + name: str | None = None + old_name = "" + price: Decimal | None = None + quantity: int | None = None + for key in fields: + if key == NAME_KEY: + name = normalize_product_name(fields[NAME_KEY]) + if not name: + print("product name must not be blank") + return None + old_name = storage[product_id][NAME_KEY] + if name != old_name and name in product_names: + print(f"product name '{name}' is already taken") + return None + + elif key == PRICE_KEY: + price = normalize_price(fields[PRICE_KEY]) + + elif key == QUANTITY_KEY: + quantity = fields[QUANTITY_KEY] + if name is not None: + product_names.remove(old_name) + product_names.add(name) + storage[product_id][NAME_KEY] = name + if price is not None: + storage[product_id][PRICE_KEY] = price + if quantity is not None: + storage[product_id][QUANTITY_KEY] = quantity + + return storage[product_id] + + +@collect_stats(DELETE_KEY, STATS_REGISTRY) def delete_product( storage: dict[int, Product], product_names: set[str], @@ -187,5 +242,9 @@ def delete_product( product carried that identifier (``storage`` and ``product_names`` are left unchanged and a message is printed). """ - # TODO: реализуйте функцию (используйте своё решение части 4) - return 0 + result: Product | None = storage.pop(product_id, None) + if result is None: + print(f"no product with id {product_id}") + return None + product_names.remove(result[NAME_KEY]) + return product_id diff --git a/src/part5/decorators.py b/src/part5/decorators.py index 21a9f237..2781678f 100644 --- a/src/part5/decorators.py +++ b/src/part5/decorators.py @@ -14,12 +14,12 @@ """ from collections.abc import Callable +from functools import wraps from typing import Final -# TODO: задайте имена двух счётчиков, см. TASK.md -SUCCESS_KEY: Final[str] = "" -FAILS_KEY: Final[str] = "" +SUCCESS_KEY: Final[str] = "success" +FAILS_KEY: Final[str] = "fails" type Stats = dict[str, int] @@ -53,5 +53,22 @@ def collect_stats[**P, R]( ``None``. The decorated function has the same signature, name and docstring as the original (see :func:`functools.wraps`). """ - # TODO: реализуйте декоратор - return lambda function: function + + def decorator(function: Callable[P, R | None]) -> Callable[P, R | None]: + if key in registry: + print(f"stats key {key!r} is already registered") + return function + registry[key] = {SUCCESS_KEY: 0, FAILS_KEY: 0} + + @wraps(function) + def wrapper(*args: P.args, **kwargs: P.kwargs) -> R | None: + result = function(*args, **kwargs) + if result is None: + registry[key][FAILS_KEY] += 1 + else: + registry[key][SUCCESS_KEY] += 1 + return result + + return wrapper + + return decorator diff --git a/src/part5/run_admin.py b/src/part5/run_admin.py index d2e83947..f7fce2aa 100644 --- a/src/part5/run_admin.py +++ b/src/part5/run_admin.py @@ -36,16 +36,38 @@ is left untouched and the loop keeps running; only ``exit`` stops it. """ -from decimal import InvalidOperation +from decimal import Decimal, InvalidOperation from typing import Final -from .storage import Product +from .crud import ( + STATS_REGISTRY, + create_product, + delete_product, + generate_snowflake_id, + read_product, + update_product, +) +from .storage import NAME_KEY, PRICE_KEY, QUANTITY_KEY, Product +from .utils import get_stats_str_representation, get_storage_str_representation # TODO: задайте приглашение и текст справки (используйте своё решение части 4, # не забудьте добавить команду stats, см. TASK.md) -PROMPT: Final[str] = "" -HELP_TEXT: Final[str] = "" +PROMPT: Final[str] = "admin> " +HELP_TEXT: Final[str] = """Available commands: + help show this message + exit leave the console + show print the whole store as a table + create add a product, print its new id + read print the product with that id + update overwrite that product's fields + delete remove the product with that id + stats print call statistics of the CRUD commands + +For create and update the price and quantity are the last two words of the +line; everything before them is the product name, so it may contain spaces +(for example "Gibson SG Junior") and needs no quoting. +""" def show_help() -> None: @@ -55,7 +77,7 @@ def show_help() -> None: is: a heading, one line per command with a short description, and a note on how multi-word names are parsed. """ - # TODO: реализуйте функцию (используйте своё решение части 4) + print(HELP_TEXT) def print_result(result: object) -> None: @@ -66,7 +88,8 @@ def print_result(result: object) -> None: operation already reported its own failure, so nothing is printed in that case. """ - # TODO: реализуйте функцию (используйте своё решение части 4) + if result is not None: + print(result) def run_command( @@ -93,8 +116,70 @@ def run_command( decimal.InvalidOperation: If the price argument of ``create`` or ``update`` does not parse as a decimal number. """ - # TODO: реализуйте функцию - return False + command = line.split() + + if not command: + print(f"'{line}' is not a command") + return True + + match command: + case ["help"]: + show_help() + return True + + case ["exit"]: + return False + + case ["show"]: + print(get_storage_str_representation(storage)) + return True + + case ["stats"]: + print(get_stats_str_representation(STATS_REGISTRY)) + return True + + case ["create", *name_parts, str_price, str_quantity]: + name = " ".join(name_parts) + price = Decimal(str_price) + quantity = int(str_quantity) + result: int | Product | None = create_product( + storage, + product_names, + {NAME_KEY: name, PRICE_KEY: price, QUANTITY_KEY: quantity}, + generate_snowflake_id, + ) + print_result(result) + return True + + case ["read", id]: + product_id = int(id) + result = read_product(storage, product_id) + print_result(result) + return True + + case ["update", id, *name_parts, str_price, str_quantity]: + product_id = int(id) + name = " ".join(name_parts) + price = Decimal(str_price) + quantity = int(str_quantity) + result = update_product( + storage, + product_names, + product_id, + {NAME_KEY: name, PRICE_KEY: price, QUANTITY_KEY: quantity}, + ) + print_result(result) + return True + + case ["delete", id]: + product_id = int(id) + result = delete_product(storage, product_names, product_id) + print_result(result) + return True + + case _: + print(f"'{line}' is not a command") + return True def main() -> None: diff --git a/src/part5/snowflake.py b/src/part5/snowflake.py index 64e28468..24143f83 100644 --- a/src/part5/snowflake.py +++ b/src/part5/snowflake.py @@ -14,9 +14,19 @@ :func:`decode_node_id` and :func:`decode_sequence_id`. """ +import time from collections.abc import Callable -from .constants import EPOCH_MS_DEFAULT, NODE_ID_DEFAULT +from .constants import ( + EPOCH_MS_DEFAULT, + NODE_ID_DEFAULT, + NODE_ID_MAX, + NODE_ID_SHIFT, + SEQUENCE_ID_MAX, + SEQUENCE_ID_SHIFT, + TIMESTAMP_MS_MAX, + TIMESTAMP_SHIFT, +) def read_current_millis(epoch_ms: int) -> int: @@ -26,11 +36,10 @@ def read_current_millis(epoch_ms: int) -> int: epoch_ms: The custom epoch expressed as Unix milliseconds. Returns: - The count of whole milliseconds between ``epoch_ms`` and now. Negative - if ``epoch_ms`` lies in the future. + The count of whole milliseconds between ``epoch_ms`` and now. May be + negative if ``epoch_ms`` lies in the future. """ - # TODO: реализуйте функцию (используйте своё решение части 1) - return 0 + return int(time.time() * 1000) - epoch_ms def decode_timestamp_ms(snowflake_id: int, epoch_ms: int = EPOCH_MS_DEFAULT) -> int: @@ -45,38 +54,34 @@ def decode_timestamp_ms(snowflake_id: int, epoch_ms: int = EPOCH_MS_DEFAULT) -> The absolute Unix time in milliseconds at which the identifier was generated. """ - # TODO: реализуйте функцию (используйте своё решение части 1) - return 0 + stored_ms = (snowflake_id >> TIMESTAMP_SHIFT) & TIMESTAMP_MS_MAX + return stored_ms + epoch_ms def decode_node_id(snowflake_id: int) -> int: """Read the node identifier field out of a Snowflake identifier. Args: - snowflake_id: An identifier produced by a generator from - :func:`get_snowflake_id_generator`. + snowflake_id: An identifier produced by :func:`generate_snowflake_id`. Returns: The node identifier packed into ``snowflake_id``, in the range ``[0, NODE_ID_MAX]``. """ - # TODO: реализуйте функцию (используйте своё решение части 1) - return 0 + return (snowflake_id >> NODE_ID_SHIFT) & NODE_ID_MAX def decode_sequence_id(snowflake_id: int) -> int: """Read the sequence counter field out of a Snowflake identifier. Args: - snowflake_id: An identifier produced by a generator from - :func:`get_snowflake_id_generator`. + snowflake_id: An identifier produced by :func:`generate_snowflake_id`. Returns: The per-millisecond sequence counter packed into ``snowflake_id``, in the range ``[0, SEQUENCE_ID_MAX]``. """ - # TODO: реализуйте функцию (используйте своё решение части 1) - return 0 + return (snowflake_id >> SEQUENCE_ID_SHIFT) & SEQUENCE_ID_MAX def get_snowflake_id_generator( @@ -108,5 +113,40 @@ def get_snowflake_id_generator( to stdout, if ``node_id`` is outside ``[0, NODE_ID_MAX]`` or ``epoch_ms`` lies in the future. """ - # TODO: реализуйте функцию - return lambda: 0 + if not (0 <= node_id <= NODE_ID_MAX): + print(f"node_id must be in [0, {NODE_ID_MAX}], got {node_id}") + return None + elapsed_ms = read_current_millis(epoch_ms) + if elapsed_ms < 0: + print(f"epoch_ms must not be in the future, got {epoch_ms}") + return None + + sequence_id = 0 + curr_ms = -1 + + def generator() -> int | None: + nonlocal curr_ms, sequence_id + elapsed_ms = read_current_millis(epoch_ms) + if curr_ms == elapsed_ms: + sequence_id += 1 + if sequence_id > SEQUENCE_ID_MAX: + print( + f"sequence_id must be in [0, {SEQUENCE_ID_MAX}], got {sequence_id}" + ) + return None + else: + curr_ms = elapsed_ms + sequence_id = 0 + + if curr_ms > TIMESTAMP_MS_MAX: + print(f"timestamp {curr_ms} ms overflows {TIMESTAMP_MS_MAX} ms") + return None + + snowflake_id = ( + (curr_ms << TIMESTAMP_SHIFT) + | (node_id << NODE_ID_SHIFT) + | (sequence_id << SEQUENCE_ID_SHIFT) + ) + return snowflake_id + + return generator diff --git a/src/part5/storage.py b/src/part5/storage.py index fa8ef3bb..3c9c8899 100644 --- a/src/part5/storage.py +++ b/src/part5/storage.py @@ -38,7 +38,6 @@ type Product = dict[str, Any] -# TODO: задайте имена полей записи (используйте своё решение части 4) -NAME_KEY: Final = "" -PRICE_KEY: Final = "" -QUANTITY_KEY: Final = "" +NAME_KEY: Final[str] = "name" +PRICE_KEY: Final[str] = "price" +QUANTITY_KEY: Final[str] = "quantity" diff --git a/src/part5/utils.py b/src/part5/utils.py index b2ad4dc4..891fe020 100644 --- a/src/part5/utils.py +++ b/src/part5/utils.py @@ -21,23 +21,26 @@ look, with the success rate of every command as a percentage. """ -from decimal import Decimal +from decimal import ROUND_HALF_UP, Decimal +from re import sub from typing import Final -from .decorators import Registry -from .storage import Product +from .decorators import FAILS_KEY, SUCCESS_KEY, Registry +from .storage import NAME_KEY, PRICE_KEY, QUANTITY_KEY, Product -# TODO: задайте число знаков после запятой и шаг квантования (используйте своё -# решение части 4) -PRICE_PRECISION: Final[int] = 0 -PRICE_STEP: Final = Decimal(0) +PRICE_PRECISION: Final[int] = 2 +PRICE_STEP: Final = Decimal(1).scaleb(-PRICE_PRECISION) -# TODO: задайте заголовки столбцов таблицы (используйте своё решение части 4) -TABLE_HEADERS: Final[tuple[str, ...]] = () -# TODO: задайте заголовки столбцов таблицы статистики, см. TASK.md -STATS_TABLE_HEADERS: Final[tuple[str, ...]] = () +TABLE_HEADERS: Final[tuple[str, ...]] = ("ID", "name", "price", "quantity") + +STATS_TABLE_HEADERS: Final[tuple[str, ...]] = ( + "command name", + "success", + "fails", + "success rate", +) def normalize_price(price: Decimal) -> Decimal: @@ -50,8 +53,7 @@ def normalize_price(price: Decimal) -> Decimal: ``price`` quantised to :data:`PRICE_PRECISION` fractional digits, with halves rounded up. """ - # TODO: реализуйте функцию (используйте своё решение части 4) - return Decimal(0) + return price.quantize(PRICE_STEP, ROUND_HALF_UP) def normalize_product_name(name: str) -> str: @@ -68,11 +70,16 @@ def normalize_product_name(name: str) -> str: The result is an empty string when ``name`` holds nothing but whitespace. """ - # TODO: реализуйте функцию (используйте своё решение части 4) - return "" + return sub(r"\s+", " ", name.strip()).lower() + + +def format_row(values: list[str] | tuple[str, ...], widths: list[int]) -> str: + cells = [values[i].ljust(widths[i]) for i in range(len(widths))] + return "| " + " | ".join(cells) + " |" -# TODO: при необходимости добавьте свои вспомогательные функции +def separator(widths: list[int]) -> str: + return "|" + "|".join(["-" * (w + 2) for w in widths]) + "|" def get_storage_str_representation(storage: dict[int, Product]) -> str: @@ -93,8 +100,28 @@ def get_storage_str_representation(storage: dict[int, Product]) -> str: ``storage`` is empty only the header and separator rows are returned, sized to the header labels. """ - # TODO: реализуйте функцию (используйте своё решение части 4) - return "" + rows: list[list[str]] = [] + for ID, value in storage.items(): + product: Product = value + rows.append( + [ + str(ID), + product[NAME_KEY], + str(product[PRICE_KEY]), + str(product[QUANTITY_KEY]), + ] + ) + + widths: list[int] = [len(h) for h in TABLE_HEADERS] + for row in rows: + for i in range(len(row)): + widths[i] = max(widths[i], len(row[i])) + + lines = [format_row(TABLE_HEADERS, widths), separator(widths)] + for row in rows: + lines.append(format_row(row, widths)) + + return "\n".join(lines) def get_stats_str_representation(registry: Registry) -> str: @@ -116,5 +143,22 @@ def get_stats_str_representation(registry: Registry) -> str: empty only the header and separator rows are returned, sized to the header labels. """ - # TODO: реализуйте функцию - return "" + rows: list[list[str]] = [] + for name, value in registry.items(): + if value[SUCCESS_KEY] + value[FAILS_KEY] == 0: + share = 0 + else: + share = value[SUCCESS_KEY] / (value[SUCCESS_KEY] + value[FAILS_KEY]) * 100 + rate = f"{share:.2f}%" + rows.append([name, str(value[SUCCESS_KEY]), str(value[FAILS_KEY]), rate]) + + widths: list[int] = [len(h) for h in STATS_TABLE_HEADERS] + for row in rows: + for i in range(len(row)): + widths[i] = max(widths[i], len(row[i])) + + lines = [format_row(STATS_TABLE_HEADERS, widths), separator(widths)] + for row in rows: + lines.append(format_row(row, widths)) + + return "\n".join(lines) From ebdccb7c7a64950de1e3f9aad107237b687e4eb4 Mon Sep 17 00:00:00 2001 From: Andrey Rudakov Date: Thu, 12 Nov 2026 15:46:22 +0300 Subject: [PATCH 10/10] small fixes --- src/part5/constants.py | 3 --- src/part5/run_admin.py | 2 -- src/part5/utils.py | 2 +- 3 files changed, 1 insertion(+), 6 deletions(-) diff --git a/src/part5/constants.py b/src/part5/constants.py index c49f0781..167d5ed6 100644 --- a/src/part5/constants.py +++ b/src/part5/constants.py @@ -31,9 +31,6 @@ NODE_ID_MAX: Final[int] = (1 << NODE_ID_BITS) - 1 SEQUENCE_ID_MAX: Final[int] = (1 << SEQUENCE_ID_BITS) - 1 -# Здесь можно добавить собственные вспомогательные константы -# (например, сдвиги полей при сборке идентификатора). - # Shift amounts SEQUENCE_ID_SHIFT: Final[int] = 0 NODE_ID_SHIFT: Final[int] = SEQUENCE_ID_BITS diff --git a/src/part5/run_admin.py b/src/part5/run_admin.py index f7fce2aa..5569f246 100644 --- a/src/part5/run_admin.py +++ b/src/part5/run_admin.py @@ -51,8 +51,6 @@ from .utils import get_stats_str_representation, get_storage_str_representation -# TODO: задайте приглашение и текст справки (используйте своё решение части 4, -# не забудьте добавить команду stats, см. TASK.md) PROMPT: Final[str] = "admin> " HELP_TEXT: Final[str] = """Available commands: help show this message diff --git a/src/part5/utils.py b/src/part5/utils.py index 891fe020..0920a9d7 100644 --- a/src/part5/utils.py +++ b/src/part5/utils.py @@ -146,7 +146,7 @@ def get_stats_str_representation(registry: Registry) -> str: rows: list[list[str]] = [] for name, value in registry.items(): if value[SUCCESS_KEY] + value[FAILS_KEY] == 0: - share = 0 + share = 0.0 else: share = value[SUCCESS_KEY] / (value[SUCCESS_KEY] + value[FAILS_KEY]) * 100 rate = f"{share:.2f}%"