xsecuremcp / tests /utilities /test_cache.py
Jeremiah Lowin
Fix typing and static issues
2627940
Raw
History Blame
8.14 kB
"""Tests for the cache.py module."""
import datetime
import time
from unittest.mock import patch
from fastmcp.utilities.cache import TimedCache
class TestTimedCache:
"""Tests for the TimedCache class."""
def test_init(self):
"""Test that a TimedCache can be initialized with an expiration."""
expiration = datetime.timedelta(seconds=10)
cache = TimedCache(expiration)
assert cache.expiration == expiration
assert isinstance(cache.cache, dict)
assert len(cache.cache) == 0
def test_set(self):
"""Test that values can be set in the cache."""
cache = TimedCache(datetime.timedelta(seconds=10))
key, value = "test_key", "test_value"
with patch("datetime.datetime") as mock_datetime:
now = datetime.datetime(2023, 1, 1, tzinfo=datetime.timezone.utc)
mock_datetime.now.return_value = now
cache.set(key, value)
# Check that the value is stored with the correct expiration
assert key in cache.cache
stored_value, expiration = cache.cache[key]
assert stored_value == value
assert expiration == now + datetime.timedelta(seconds=10)
def test_get_found(self):
"""Test retrieving a value that exists and has not expired."""
cache = TimedCache(datetime.timedelta(seconds=10))
key, value = "test_key", "test_value"
# Set a future expiration time
future = datetime.datetime.now(datetime.timezone.utc) + datetime.timedelta(
seconds=30
)
cache.cache[key] = (value, future)
# The value should be returned
assert cache.get(key) == value
def test_get_expired(self):
"""Test retrieving a value that exists but has expired."""
cache = TimedCache(datetime.timedelta(seconds=10))
key, value = "test_key", "test_value"
# Set a past expiration time
past = datetime.datetime.now(datetime.timezone.utc) - datetime.timedelta(
seconds=1
)
cache.cache[key] = (value, past)
# Should return NOT_FOUND
assert cache.get(key) is TimedCache.NOT_FOUND
def test_get_not_found(self):
"""Test retrieving a value that doesn't exist in the cache."""
cache = TimedCache(datetime.timedelta(seconds=10))
# Key doesn't exist
assert cache.get("nonexistent_key") is TimedCache.NOT_FOUND
def test_clear(self):
"""Test that the cache can be cleared."""
cache = TimedCache(datetime.timedelta(seconds=10))
# Add some items
cache.set("key1", "value1")
cache.set("key2", "value2")
assert len(cache.cache) == 2
# Clear the cache
cache.clear()
assert len(cache.cache) == 0
def test_real_expiration(self):
"""Test that values actually expire after the specified time."""
# Use a very short expiration for the test
cache = TimedCache(datetime.timedelta(milliseconds=50))
key, value = "test_key", "test_value"
cache.set(key, value)
# Value should be available immediately
assert cache.get(key) == value
# Wait for expiration
time.sleep(0.06) # 60 milliseconds, slightly longer than expiration
# Value should now be expired
assert cache.get(key) is TimedCache.NOT_FOUND
def test_overwrite_value(self):
"""Test that setting a key that already exists overwrites the old value."""
cache = TimedCache(datetime.timedelta(seconds=10))
key = "test_key"
# Set initial value
cache.set(key, "initial_value")
assert cache.get(key) == "initial_value"
# Overwrite with new value
cache.set(key, "new_value")
assert cache.get(key) == "new_value"
def test_extends_expiration_on_overwrite(self):
"""Test that overwriting a key extends its expiration time."""
cache = TimedCache(datetime.timedelta(seconds=10))
key = "test_key"
with patch("datetime.datetime") as mock_datetime:
# Set initial value at t=0
initial_time = datetime.datetime(2023, 1, 1, tzinfo=datetime.timezone.utc)
mock_datetime.now.return_value = initial_time
cache.set(key, "initial_value")
initial_expiration = cache.cache[key][1]
assert initial_expiration == initial_time + datetime.timedelta(seconds=10)
# Overwrite at t=5
later_time = initial_time + datetime.timedelta(seconds=5)
mock_datetime.now.return_value = later_time
cache.set(key, "new_value")
# Expiration should be extended
new_expiration = cache.cache[key][1]
assert new_expiration == later_time + datetime.timedelta(seconds=10)
def test_different_key_types(self):
"""Test that different types of keys can be used."""
cache = TimedCache(datetime.timedelta(seconds=10))
# Test various key types
keys_and_values = [
(42, "int_value"),
(3.14, "float_value"),
((1, 2), "tuple_value"),
(frozenset({1, 2, 3}), "frozenset_value"),
]
for key, value in keys_and_values:
cache.set(key, value)
assert cache.get(key) == value
def test_none_value(self):
"""Test that None can be stored as a value."""
cache = TimedCache(datetime.timedelta(seconds=10))
key = "none_key"
cache.set(key, None)
# The stored value is None, but get() should return None, not NOT_FOUND
assert cache.get(key) is None
def test_edge_case_zero_expiration(self):
"""Test with a zero expiration time."""
cache = TimedCache(datetime.timedelta(seconds=0))
key, value = "test_key", "test_value"
cache.set(key, value)
# The value might already be expired by the time we call get()
# We can't make strong assertions here due to timing variability
retrieved = cache.get(key)
assert retrieved in (value, TimedCache.NOT_FOUND)
def test_negative_expiration(self):
"""Test with a negative expiration time."""
cache = TimedCache(datetime.timedelta(seconds=-1))
key, value = "test_key", "test_value"
cache.set(key, value)
# Value should be immediately expired
assert cache.get(key) is TimedCache.NOT_FOUND
def test_cache_consistency(self):
"""Test cache consistency with multiple operations."""
cache = TimedCache(datetime.timedelta(seconds=10))
# Add multiple items
cache.set("key1", "value1")
cache.set("key2", "value2")
cache.set("key3", "value3")
# Check all items
assert cache.get("key1") == "value1"
assert cache.get("key2") == "value2"
assert cache.get("key3") == "value3"
# Overwrite one item
cache.set("key2", "updated_value")
# Check again
assert cache.get("key1") == "value1"
assert cache.get("key2") == "updated_value"
assert cache.get("key3") == "value3"
# Clear and verify all items are gone
cache.clear()
assert cache.get("key1") is TimedCache.NOT_FOUND
assert cache.get("key2") is TimedCache.NOT_FOUND
assert cache.get("key3") is TimedCache.NOT_FOUND
def test_large_expiration(self):
"""Test with a very large expiration time."""
# One year expiration
cache = TimedCache(datetime.timedelta(days=365))
key, value = "test_key", "test_value"
cache.set(key, value)
assert cache.get(key) == value
def test_many_items(self):
"""Test cache with many items."""
cache = TimedCache(datetime.timedelta(seconds=10))
# Add 1000 items
for i in range(1000):
cache.set(f"key{i}", f"value{i}")
# Check size
assert len(cache.cache) == 1000
# Check some random items
for i in [0, 123, 456, 789, 999]:
assert cache.get(f"key{i}") == f"value{i}"