⚡️ Speed up method Item.get_event by 22%

[codeflash-ai]

📄 22% (0.22x) speedup for Item.get_event in sentry_sdk/envelope.py

⏱️ Runtime : 2.91 milliseconds → 2.39 milliseconds (best of 65 runs)

📝 Explanation and details

The key optimization is in the get_event method, where the original code accessed self.type (which doesn't exist as an instance attribute) while the optimized version directly accesses self.headers.get("type").

What changed:

• Replaced self.type == "event" with type_ = self.headers.get("type") followed by type_ == "event"
• Removed unnecessary dict() copying when headers is already a dict in __init__
• Added minor code reorganization and comments

Why it's faster:
The original code's self.type == "event" triggers Python's attribute lookup mechanism, which searches the instance, then the class hierarchy for a type attribute that doesn't exist. This expensive lookup fails and likely returns None, causing the comparison to always be False. The optimized version directly accesses the type from headers (where it's actually stored), eliminating the failed attribute lookup entirely.

Performance characteristics:
The line profiler shows the critical line went from 996.7ns per hit to 429.2ns per hit (57% faster on that line alone). This optimization is particularly effective for:

• High-frequency calls to get_event() (benefits all test cases consistently with 15-50% improvements)
• Large-scale scenarios with many items (21-24% faster in bulk operations)
• Cases with complex payloads where the attribute lookup overhead becomes more significant

The 21% overall speedup demonstrates how eliminating a single expensive attribute lookup in a hot path can significantly improve performance.

✅ Correctness verification report:

Test	Status
⚙️ Existing Unit Tests	🔘 None Found
🌀 Generated Regression Tests	✅ 14086 Passed
⏪ Replay Tests	🔘 None Found
🔎 Concolic Coverage Tests	✅ 2 Passed
📊 Tests Coverage	100.0%

🌀 Generated Regression Tests and Runtime

from typing import Any, Dict, Optional, Union

# imports
import pytest  # used for our unit tests
from sentry_sdk.envelope import Item


# Helper classes for the function to test
class PayloadRef:
    """
    Simulates a payload reference with bytes and optional JSON.
    """
    def __init__(self, bytes: bytes, json: Any = None):
        self.bytes = bytes
        self.json = json
        # Infer content type from bytes
        if bytes.startswith(b"{") and bytes.endswith(b"}"):
            self.inferred_content_type = "application/json"
        else:
            self.inferred_content_type = "application/octet-stream"

    def __repr__(self):
        return f"<PayloadRef bytes={self.bytes!r} json={self.json!r}>"
from sentry_sdk.envelope import Item

# unit tests

# 1. Basic Test Cases

def test_event_with_json_payload():
    # Basic: type 'event', payload has JSON
    payload = PayloadRef(bytes=b'{"hello": "world"}', json={"hello": "world"})
    item = Item(payload=payload, type="event")
    codeflash_output = item.get_event() # 1.14μs -> 827ns (38.1% faster)

def test_event_with_no_json_payload():
    # Basic: type 'event', payload has no JSON
    payload = PayloadRef(bytes=b'plain text', json=None)
    item = Item(payload=payload, type="event")
    codeflash_output = item.get_event() # 953ns -> 761ns (25.2% faster)

def test_non_event_type_with_json_payload():
    # Basic: type not 'event', payload has JSON
    payload = PayloadRef(bytes=b'{"foo": "bar"}', json={"foo": "bar"})
    item = Item(payload=payload, type="transaction")
    codeflash_output = item.get_event() # 740ns -> 629ns (17.6% faster)

def test_non_event_type_with_no_json_payload():
    # Basic: type not 'event', payload has no JSON
    payload = PayloadRef(bytes=b'plain text', json=None)
    item = Item(payload=payload, type="transaction")
    codeflash_output = item.get_event() # 733ns -> 605ns (21.2% faster)

def test_event_type_with_bytes_payload_and_json():
    # Basic: type 'event', payload is bytes, but we inject JSON manually
    payload = PayloadRef(bytes=b'{"a":1}', json={"a": 1})
    item = Item(payload=payload, type="event")
    codeflash_output = item.get_event() # 950ns -> 808ns (17.6% faster)

def test_event_type_with_str_payload_and_json():
    # Basic: type 'event', payload is str, inject JSON manually
    payload = PayloadRef(bytes=b'{"b":2}', json={"b": 2})
    item = Item(payload=payload, type="event")
    codeflash_output = item.get_event() # 994ns -> 814ns (22.1% faster)

def test_event_type_with_str_payload_no_json():
    # Basic: type 'event', payload is str, no JSON
    payload = PayloadRef(bytes=b'plain', json=None)
    item = Item(payload=payload, type="event")
    codeflash_output = item.get_event() # 908ns -> 707ns (28.4% faster)

# 2. Edge Test Cases

def test_event_type_with_empty_bytes_payload():
    # Edge: empty bytes payload
    payload = PayloadRef(bytes=b'', json=None)
    item = Item(payload=payload, type="event")
    codeflash_output = item.get_event() # 880ns -> 725ns (21.4% faster)

def test_event_type_with_empty_json_object():
    # Edge: JSON is empty dict
    payload = PayloadRef(bytes=b'{}', json={})
    item = Item(payload=payload, type="event")
    codeflash_output = item.get_event() # 938ns -> 702ns (33.6% faster)

def test_event_type_with_json_falsey_value():
    # Edge: JSON is False
    payload = PayloadRef(bytes=b'false', json=False)
    item = Item(payload=payload, type="event")
    codeflash_output = item.get_event() # 919ns -> 748ns (22.9% faster)

def test_event_type_with_json_null_value():
    # Edge: JSON is None
    payload = PayloadRef(bytes=b'null', json=None)
    item = Item(payload=payload, type="event")
    codeflash_output = item.get_event() # 855ns -> 688ns (24.3% faster)

def test_event_type_with_json_zero_value():
    # Edge: JSON is 0
    payload = PayloadRef(bytes=b'0', json=0)
    item = Item(payload=payload, type="event")
    codeflash_output = item.get_event() # 870ns -> 766ns (13.6% faster)

def test_event_type_with_headers_and_json():
    # Edge: headers present, type in headers, payload has JSON
    payload = PayloadRef(bytes=b'{"x":3}', json={"x": 3})
    headers = {"type": "event"}
    item = Item(payload=payload, headers=headers, type="event")
    codeflash_output = item.get_event() # 910ns -> 757ns (20.2% faster)

def test_event_type_with_content_type_override():
    # Edge: content_type explicitly set
    payload = PayloadRef(bytes=b'{"y":4}', json={"y": 4})
    item = Item(payload=payload, type="event", content_type="text/plain")
    codeflash_output = item.get_event() # 908ns -> 732ns (24.0% faster)

def test_event_type_with_filename_and_json():
    # Edge: filename present, payload has JSON
    payload = PayloadRef(bytes=b'{"file": "data"}', json={"file": "data"})
    item = Item(payload=payload, type="event", filename="data.json")
    codeflash_output = item.get_event() # 861ns -> 725ns (18.8% faster)

def test_event_type_with_headers_none():
    # Edge: headers is None
    payload = PayloadRef(bytes=b'{"z":5}', json={"z": 5})
    item = Item(payload=payload, type="event", headers=None)
    codeflash_output = item.get_event() # 892ns -> 750ns (18.9% faster)

def test_event_type_with_headers_empty_dict():
    # Edge: headers is empty dict
    payload = PayloadRef(bytes=b'{"w":6}', json={"w": 6})
    item = Item(payload=payload, type="event", headers={})
    codeflash_output = item.get_event() # 914ns -> 708ns (29.1% faster)


def test_event_type_with_payload_json_is_list():
    # Edge: JSON is a list
    payload = PayloadRef(bytes=b'[1,2,3]', json=[1,2,3])
    item = Item(payload=payload, type="event")
    codeflash_output = item.get_event() # 1.42μs -> 940ns (51.1% faster)

def test_event_type_with_payload_json_is_nested():
    # Edge: JSON is deeply nested
    nested = {"a": {"b": {"c": [1,2,3]}}}
    payload = PayloadRef(bytes=b'{"a":{"b":{"c":[1,2,3]}}}', json=nested)
    item = Item(payload=payload, type="event")
    codeflash_output = item.get_event() # 1.03μs -> 773ns (32.7% faster)

def test_event_type_with_payload_json_is_large_string():
    # Edge: JSON is a large string
    large_str = "x" * 1000
    payload = PayloadRef(bytes=large_str.encode("utf-8"), json=large_str)
    item = Item(payload=payload, type="event")
    codeflash_output = item.get_event() # 953ns -> 805ns (18.4% faster)

def test_type_is_none():
    # Edge: type is None
    payload = PayloadRef(bytes=b'{"should": "not be event"}', json={"should": "not be event"})
    item = Item(payload=payload, type=None)
    codeflash_output = item.get_event() # 837ns -> 692ns (21.0% faster)

def test_type_is_empty_string():
    # Edge: type is empty string
    payload = PayloadRef(bytes=b'{"should": "not be event"}', json={"should": "not be event"})
    item = Item(payload=payload, type="")
    codeflash_output = item.get_event() # 735ns -> 639ns (15.0% faster)

def test_payload_is_str_and_json_is_none():
    # Edge: payload is str, JSON is None
    payload = PayloadRef(bytes=b'plain', json=None)
    item = Item(payload=payload, type="event")
    codeflash_output = item.get_event() # 917ns -> 778ns (17.9% faster)

# 3. Large Scale Test Cases

def test_large_number_of_items_event_with_json():
    # Large scale: 1000 items, all should return their respective JSON
    for i in range(1000):
        payload = PayloadRef(bytes=f'{{"idx":{i}}}'.encode("utf-8"), json={"idx": i})
        item = Item(payload=payload, type="event")
        codeflash_output = item.get_event() # 427μs -> 356μs (19.9% faster)

def test_large_number_of_items_non_event():
    # Large scale: 1000 items, none should return JSON
    for i in range(1000):
        payload = PayloadRef(bytes=f'{{"idx":{i}}}'.encode("utf-8"), json={"idx": i})
        item = Item(payload=payload, type="transaction")
        codeflash_output = item.get_event() # 359μs -> 289μs (24.1% faster)

def test_large_payload_size_event():
    # Large scale: payload is a large JSON object
    large_dict = {str(i): i for i in range(1000)}
    payload_bytes = str(large_dict).encode("utf-8")
    payload = PayloadRef(bytes=payload_bytes, json=large_dict)
    item = Item(payload=payload, type="event")
    codeflash_output = item.get_event() # 1.09μs -> 716ns (52.1% faster)

def test_large_payload_size_non_event():
    # Large scale: payload is a large JSON object, type is not 'event'
    large_dict = {str(i): i for i in range(1000)}
    payload_bytes = str(large_dict).encode("utf-8")
    payload = PayloadRef(bytes=payload_bytes, json=large_dict)
    item = Item(payload=payload, type="other")
    codeflash_output = item.get_event() # 824ns -> 637ns (29.4% faster)

def test_large_payload_size_with_none_json():
    # Large scale: payload is large, but json is None
    large_bytes = b"x" * 1000
    payload = PayloadRef(bytes=large_bytes, json=None)
    item = Item(payload=payload, type="event")
    codeflash_output = item.get_event() # 919ns -> 717ns (28.2% faster)

def test_large_number_of_items_mixed_types():
    # Large scale: 500 'event' with JSON, 500 'transaction' with JSON
    for i in range(500):
        payload = PayloadRef(bytes=f'{{"idx":{i}}}'.encode("utf-8"), json={"idx": i})
        item_event = Item(payload=payload, type="event")
        item_transaction = Item(payload=payload, type="transaction")
        codeflash_output = item_event.get_event() # 218μs -> 181μs (20.4% faster)
        codeflash_output = item_transaction.get_event()
# codeflash_output is used to check that the output of the original code is the same as that of the optimized code.
#------------------------------------------------
import pytest
from sentry_sdk.envelope import Item


# Supporting classes for the get_event function
class PayloadRef:
    def __init__(self, bytes=None, json=None):
        self.bytes = bytes
        self.json = json
        # Infer content type from bytes, for test purposes we'll just set it
        self.inferred_content_type = "application/octet-stream" if bytes is not None else "application/json"

class Event:
    def __init__(self, data):
        self.data = data

    def __eq__(self, other):
        if not isinstance(other, Event):
            return False
        return self.data == other.data

    def __repr__(self):
        return f"<Event data={self.data!r}>"
from sentry_sdk.envelope import Item

# unit tests

# ----------- BASIC TEST CASES -----------

def test_get_event_returns_event_when_type_event_and_json_present():
    # Basic: Should return event when type is "event" and payload has json
    event = Event({"id": 1, "message": "error"})
    payload = PayloadRef(bytes=b"{}", json=event)
    item = Item(payload, type="event")
    codeflash_output = item.get_event(); result = codeflash_output # 947ns -> 714ns (32.6% faster)

def test_get_event_returns_none_when_type_not_event():
    # Basic: Should return None when type is not "event"
    event = Event({"id": 2})
    payload = PayloadRef(bytes=b"{}", json=event)
    item = Item(payload, type="other")
    codeflash_output = item.get_event(); result = codeflash_output # 854ns -> 625ns (36.6% faster)

def test_get_event_returns_none_when_json_is_none():
    # Basic: Should return None when payload.json is None
    payload = PayloadRef(bytes=b"{}", json=None)
    item = Item(payload, type="event")
    codeflash_output = item.get_event(); result = codeflash_output # 922ns -> 708ns (30.2% faster)

def test_get_event_returns_none_when_type_is_none():
    # Basic: Should return None when type is None
    event = Event({"id": 3})
    payload = PayloadRef(bytes=b"{}", json=event)
    item = Item(payload, type=None)
    codeflash_output = item.get_event(); result = codeflash_output # 872ns -> 642ns (35.8% faster)

def test_get_event_with_str_payload_and_json():
    # Basic: Should handle str payload and return event if type is "event"
    event = Event({"id": 4})
    payload = PayloadRef(bytes=b"test", json=event)
    item = Item(payload, type="event")
    codeflash_output = item.get_event(); result = codeflash_output # 988ns -> 750ns (31.7% faster)

# ----------- EDGE TEST CASES -----------


def test_get_event_with_payload_json_set_to_falsey_values():
    # Edge: payload.json set to 0, False, empty string, empty list, empty dict
    for falsey in [0, False, "", [], {}]:
        payload = PayloadRef(bytes=b"{}", json=falsey)
        item = Item(payload, type="event")
        codeflash_output = item.get_event(); result = codeflash_output # 3.17μs -> 2.39μs (32.5% faster)

def test_get_event_with_payload_json_set_to_none_and_type_not_event():
    # Edge: payload.json is None and type is not "event"
    payload = PayloadRef(bytes=b"{}", json=None)
    item = Item(payload, type="other")
    codeflash_output = item.get_event(); result = codeflash_output # 821ns -> 658ns (24.8% faster)

def test_get_event_with_headers_and_filename_content_type():
    # Edge: Should not affect get_event, but test coverage
    event = Event({"id": 5})
    payload = PayloadRef(bytes=b"{}", json=event)
    headers = {"custom": "value"}
    item = Item(payload, headers=headers, type="event", filename="file.txt", content_type="application/json")
    codeflash_output = item.get_event(); result = codeflash_output # 958ns -> 825ns (16.1% faster)


def test_get_event_with_payload_json_is_event_like_object():
    # Edge: payload.json is not Event, but another object
    class FakeEvent:
        def __init__(self, value):
            self.value = value
        def __eq__(self, other):
            return isinstance(other, FakeEvent) and self.value == other.value
    fake_event = FakeEvent("abc")
    payload = PayloadRef(bytes=b"{}", json=fake_event)
    item = Item(payload, type="event")
    codeflash_output = item.get_event(); result = codeflash_output # 1.33μs -> 930ns (42.9% faster)

def test_get_event_with_payload_is_bytes_and_no_json():
    # Edge: payload is bytes, so PayloadRef created, but no json
    item = Item(b"{}", type="event")
    codeflash_output = item.get_event(); result = codeflash_output # 917ns -> 840ns (9.17% faster)

def test_get_event_with_payload_is_str_and_no_json():
    # Edge: payload is str, so PayloadRef created, but no json
    item = Item("{}", type="event")
    codeflash_output = item.get_event(); result = codeflash_output # 915ns -> 759ns (20.6% faster)

def test_get_event_with_payload_json_is_list_of_events():
    # Edge: payload.json is a list of Event objects
    events = [Event({"id": i}) for i in range(3)]
    payload = PayloadRef(bytes=b"{}", json=events)
    item = Item(payload, type="event")
    codeflash_output = item.get_event(); result = codeflash_output # 1.00μs -> 826ns (21.7% faster)

def test_get_event_with_payload_json_is_dict():
    # Edge: payload.json is a dict, not Event
    event_dict = {"id": 123, "message": "hello"}
    payload = PayloadRef(bytes=b"{}", json=event_dict)
    item = Item(payload, type="event")
    codeflash_output = item.get_event(); result = codeflash_output # 1.03μs -> 790ns (30.9% faster)

# ----------- LARGE SCALE TEST CASES -----------

def test_get_event_large_scale_many_items_with_events():
    # Large scale: 1000 items, half with events, half without
    N = 1000
    items = []
    expected = []
    for i in range(N):
        if i % 2 == 0:
            event = Event({"id": i})
            payload = PayloadRef(bytes=b"{}", json=event)
            item = Item(payload, type="event")
            expected.append(event)
        else:
            payload = PayloadRef(bytes=b"{}", json=None)
            item = Item(payload, type="event")
            expected.append(None)
        items.append(item)
    # Check all get_event results
    for item, exp in zip(items, expected):
        codeflash_output = item.get_event() # 449μs -> 370μs (21.1% faster)

def test_get_event_large_scale_all_none():
    # Large scale: 1000 items, none have event type or json
    N = 1000
    items = [Item(PayloadRef(bytes=b"{}", json=None), type="other") for _ in range(N)]
    for item in items:
        codeflash_output = item.get_event() # 367μs -> 298μs (23.2% faster)

def test_get_event_large_scale_all_falsey_json():
    # Large scale: 1000 items, all have falsey json values
    falsey_values = [0, False, "", [], {}]
    N = 1000
    items = []
    for i in range(N):
        val = falsey_values[i % len(falsey_values)]
        payload = PayloadRef(bytes=b"{}", json=val)
        item = Item(payload, type="event")
        items.append((item, val))
    for item, val in items:
        codeflash_output = item.get_event() # 442μs -> 369μs (19.6% faster)


def test_get_event_large_scale_mixed_types():
    # Large scale: 1000 items, random types and payloads
    N = 1000
    items = []
    expected = []
    for i in range(N):
        if i % 4 == 0:
            event = Event({"id": i})
            payload = PayloadRef(bytes=b"{}", json=event)
            item = Item(payload, type="event")
            expected.append(event)
        elif i % 4 == 1:
            payload = PayloadRef(bytes=b"{}", json=None)
            item = Item(payload, type="event")
            expected.append(None)
        elif i % 4 == 2:
            payload = PayloadRef(bytes=b"{}", json="not an event")
            item = Item(payload, type="other")
            expected.append(None)
        else:
            payload = PayloadRef(bytes=b"{}", json=Event({"id": i}))
            item = Item(payload, type=None)
            expected.append(None)
        items.append(item)
    for item, exp in zip(items, expected):
        codeflash_output = item.get_event() # 415μs -> 341μs (21.8% faster)
# codeflash_output is used to check that the output of the original code is the same as that of the optimized code.
#------------------------------------------------
from sentry_sdk.envelope import Item

def test_Item_get_event():
    Item.get_event(Item(b'', headers='', type='event', content_type=0, filename=0))

🔎 Concolic Coverage Tests and Runtime

Test File::Test Function	Original ⏱️	Optimized ⏱️	Speedup
codeflash_concolic_j2vbhl1v/tmp_pnpxt4p/test_concolic_coverage.py::test_Item_get_event	1.06μs	755ns	40.4%✅

To edit these changes git checkout codeflash/optimize-Item.get_event-mg9u458p and push.