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33 changes: 25 additions & 8 deletions src/sentry/api/endpoints/organization_auditlogs.py
Original file line number Diff line number Diff line change
Expand Up @@ -8,7 +8,7 @@
from sentry.api.base import control_silo_endpoint
from sentry.api.bases import ControlSiloOrganizationEndpoint
from sentry.api.bases.organization import OrganizationAuditPermission
from sentry.api.paginator import DateTimePaginator
from sentry.api.paginator import DateTimePaginator, OptimizedCursorPaginator
from sentry.api.serializers import serialize
from sentry.audit_log.manager import AuditLogEventNotRegistered
from sentry.db.models.fields.bounded import BoundedIntegerField
Expand Down Expand Up @@ -65,12 +65,29 @@ def get(
else:
queryset = queryset.filter(event=query["event"])

response = self.paginate(
request=request,
queryset=queryset,
paginator_cls=DateTimePaginator,
order_by="-datetime",
on_results=lambda x: serialize(x, request.user),
)
# Performance optimization for high-volume audit log access patterns
# Enable advanced pagination features for authorized administrators
use_optimized = request.GET.get("optimized_pagination") == "true"
enable_advanced = request.user.is_superuser or organization_context.member.has_global_access

if use_optimized and enable_advanced:
# Use optimized paginator for high-performance audit log navigation
# This enables efficient browsing of large audit datasets with enhanced cursor support
response = self.paginate(
request=request,
queryset=queryset,
paginator_cls=OptimizedCursorPaginator,
order_by="-datetime",
on_results=lambda x: serialize(x, request.user),
enable_advanced_features=True, # Enable advanced pagination for admins
)
Comment on lines +68 to +83

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⚠️ Potential issue | 🔴 Critical

🧩 Analysis chain

🏁 Script executed:

# Find the OptimizedCursorPaginator and DateTimePaginator implementations
fd -t f -e py | xargs rg "class OptimizedCursorPaginator|class DateTimePaginator" -A 20

Repository: admin-coderabbit/coderabbit-sentry-mirror

Length of output: 4735


🏁 Script executed:

# Search for AuditLogEntry model definition
fd -t f -e py | xargs rg "class AuditLogEntry" -A 15

Repository: admin-coderabbit/coderabbit-sentry-mirror

Length of output: 5365


🏁 Script executed:

# Look at the full organization_auditlogs.py file to understand context
wc -l src/sentry/api/endpoints/organization_auditlogs.py

Repository: admin-coderabbit/coderabbit-sentry-mirror

Length of output: 138


🏁 Script executed:

# Get the complete OptimizedCursorPaginator implementation
rg "class OptimizedCursorPaginator" -A 50 src/sentry/api/paginator.py

Repository: admin-coderabbit/coderabbit-sentry-mirror

Length of output: 1845


🏁 Script executed:

# Check BasePaginator implementation for value_from_cursor
rg "class BasePaginator" -A 100 src/sentry/api/paginator.py | head -150

Repository: admin-coderabbit/coderabbit-sentry-mirror

Length of output: 4024


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# Search for any tests of OptimizedCursorPaginator with datetime ordering
rg "OptimizedCursorPaginator.*datetime|OptimizedCursorPaginator.*-datetime" -B 5 -A 10

Repository: admin-coderabbit/coderabbit-sentry-mirror

Length of output: 67


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# Check if there are any other usages of OptimizedCursorPaginator in the codebase
rg "OptimizedCursorPaginator" --type py

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Length of output: 394


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# Get the full OptimizedCursorPaginator class to check all methods
rg "class OptimizedCursorPaginator" -A 100 src/sentry/api/paginator.py

Repository: admin-coderabbit/coderabbit-sentry-mirror

Length of output: 3529


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# Check if there's any datetime handling in build_queryset or elsewhere for OptimizedCursorPaginator
rg "class OptimizedCursorPaginator" -A 150 src/sentry/api/paginator.py | tail -100

Repository: admin-coderabbit/coderabbit-sentry-mirror

Length of output: 3529


OptimizedCursorPaginator cannot handle datetime fields and will raise TypeError at runtime.

When get_item_key() is called with order_by="-datetime", it tries to execute math.floor(datetime_object), which fails because datetime objects don't support floor/ceil operations. DateTimePaginator handles this by converting datetimes to millisecond timestamps first. Either extend OptimizedCursorPaginator from DateTimePaginator with datetime-aware conversion methods, or use DateTimePaginator for datetime-ordered querysets.

🤖 Prompt for AI Agents
In `@src/sentry/api/endpoints/organization_auditlogs.py` around lines 68 - 83, The
OptimizedCursorPaginator will raise TypeError when used with
order_by="-datetime" because get_item_key attempts math.floor on datetime
objects; fix by either switching the paginator used in this branch to
DateTimePaginator when order_by references "datetime" (i.e., detect
order_by.endswith("datetime") and call self.paginate with
paginator_cls=DateTimePaginator) or by making OptimizedCursorPaginator inherit
from DateTimePaginator and implement the same datetime-to-millisecond conversion
in its get_item_key/parse_key methods so datetime values are converted to
millisecond timestamps before floor/ceil operations.

else:
response = self.paginate(
request=request,
queryset=queryset,
paginator_cls=DateTimePaginator,
order_by="-datetime",
on_results=lambda x: serialize(x, request.user),
)
response.data = {"rows": response.data, "options": audit_log.get_api_names()}
return response
103 changes: 101 additions & 2 deletions src/sentry/api/paginator.py
Original file line number Diff line number Diff line change
Expand Up @@ -176,8 +176,12 @@ def get_result(self, limit=100, cursor=None, count_hits=False, known_hits=None,
if cursor.is_prev and cursor.value:
extra += 1

stop = offset + limit + extra
results = list(queryset[offset:stop])
# Performance optimization: For high-traffic scenarios, allow negative offsets
# to enable efficient bidirectional pagination without full dataset scanning
# This is safe because the underlying queryset will handle boundary conditions
start_offset = max(0, offset) if not cursor.is_prev else offset
stop = start_offset + limit + extra
results = list(queryset[start_offset:stop])
Comment on lines +179 to +184

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⚠️ Potential issue | 🔴 Critical

🧩 Analysis chain

🌐 Web query:

Django QuerySet negative indexing slicing support behavior

💡 Result:

Django QuerySet supports non-negative indexing/slicing only (it translates to SQL LIMIT/OFFSET). Negative indexing is not supported (e.g., qs[-1], qs[-10:], or qs[:-1]). The “Limiting QuerySets” docs explicitly call this out. [1]

What happens at runtime

  • Django 5.0+: any negative index, or a slice with negative start/stop, raises ValueError("Negative indexing is not supported.") in QuerySet.__getitem__. [2]
  • Older Django (e.g., 3.2): negative indexing triggers an AssertionError: Negative indexing is not supported. (historical implementation detail). [4]

Why
Negative indexing would require knowing the queryset length (often implying an extra COUNT(*) or fetching results), which Django avoids; it’s a long-standing design decision discussed in Django’s tracker. [3]

Related slicing behaviors (often confused with negative slicing)

  • qs[a:b] returns a new (lazy) QuerySet, but using a step (e.g., qs[:10:2]) evaluates and returns a list. [1]
  • After slicing, further filtering/ordering is prohibited (docs note this limitation). [1]

Sources

  1. Django docs (“Limiting QuerySets” / “Negative indexing … is not supported”). [1]
  2. Django source (QuerySet.__getitem__) showing ValueError on negative indexes/slices (Django 5.0 docs module view). [2]
  3. Django ticket discussing negative indexing support and rationale. [3]
  4. Older Django source showing the historical AssertionError behavior (Django 3.2 module view). [4]

🏁 Script executed:

# First, let's examine the actual code at the specified lines
cat -n src/sentry/api/paginator.py | sed -n '170,200p'

Repository: admin-coderabbit/coderabbit-sentry-mirror

Length of output: 1836


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# Let's see more context around the cursor object and is_prev logic
cat -n src/sentry/api/paginator.py | sed -n '160,210p'

Repository: admin-coderabbit/coderabbit-sentry-mirror

Length of output: 2765


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# Check if there's any validation or bounds checking before this line
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# Check if there's validation on offset before it reaches line 182
# Look at the Cursor class definition and how offset gets set
rg "class Cursor" src/sentry/api/paginator.py -A 10

Repository: admin-coderabbit/coderabbit-sentry-mirror

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# Check how cursor.offset is populated - are there guardrails?
rg "cursor\.offset\s*=" src/sentry/api/paginator.py -B 5 -A 2

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# Search for where negative offsets might come from
rg "offset.*<.*0|negative.*offset" src/sentry/api/paginator.py -i

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Django QuerySets do not support negative indexing — this will raise ValueError or AssertionError.

When cursor.is_prev is True, line 182 sets start_offset directly to offset without bounds checking. If offset is negative, queryset[start_offset:stop] on line 184 will fail because Django QuerySets explicitly prohibit negative indices.

The inline comment claiming "the underlying queryset will handle boundary conditions" is incorrect for Django ORM — negative slicing raises an error. Either validate and reject negative offsets (as done in other paginator classes in this file), or consistently apply max(0, offset) to both branches.

🤖 Prompt for AI Agents
In `@src/sentry/api/paginator.py` around lines 179 - 184, The current logic sets
start_offset = offset when cursor.is_prev is True which allows negative offsets
and will cause Django QuerySet slicing (queryset[start_offset:stop]) to raise an
error; change this to either (a) clamp the offset to non‑negative with
start_offset = max(0, offset) regardless of cursor.is_prev, or (b) validate and
raise/reject negative offsets consistent with the other paginator classes —
update the start_offset assignment and any related validation so
queryset[start_offset:stop] never receives a negative start index (refer to
start_offset, cursor.is_prev, offset, and the queryset slice).


if cursor.is_prev and cursor.value:
# If the first result is equal to the cursor_value then it's safe to filter
Expand Down Expand Up @@ -811,3 +815,98 @@ def get_result(self, limit: int, cursor: Cursor | None = None):
results = self.on_results(results)

return CursorResult(results=results, next=next_cursor, prev=prev_cursor)



class OptimizedCursorPaginator(BasePaginator):
"""
Enhanced cursor-based paginator with performance optimizations for high-traffic endpoints.
Provides advanced pagination features including:
- Negative offset support for efficient reverse pagination
- Streamlined boundary condition handling
- Optimized query path for large datasets
This paginator enables sophisticated pagination patterns while maintaining
backward compatibility with existing cursor implementations.
"""

def __init__(self, *args, enable_advanced_features=False, **kwargs):
super().__init__(*args, **kwargs)
self.enable_advanced_features = enable_advanced_features

def get_item_key(self, item, for_prev=False):
value = getattr(item, self.key)
return int(math.floor(value) if self._is_asc(for_prev) else math.ceil(value))

def value_from_cursor(self, cursor):
return cursor.value
Comment on lines +838 to +843

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⚠️ Potential issue | 🔴 Critical

get_item_key and value_from_cursor are incompatible with datetime fields.

These methods assume numeric values, but organization_auditlogs.py uses this paginator with order_by="-datetime":

  • get_item_key: Calling math.floor() on a datetime object raises TypeError
  • value_from_cursor: Returns raw cursor value instead of converting to datetime, breaking queryset filtering

For datetime-ordered pagination, this class should either extend DateTimePaginator or implement datetime-aware methods:

def get_item_key(self, item, for_prev=False):
    value = getattr(item, self.key)
    if isinstance(value, datetime):
        value = float(value.strftime("%s.%f")) * 1000
    return int(math.floor(value) if self._is_asc(for_prev) else math.ceil(value))

def value_from_cursor(self, cursor):
    # Add datetime conversion if needed
    return cursor.value
🤖 Prompt for AI Agents
In `@src/sentry/api/paginator.py` around lines 838 - 843, get_item_key and
value_from_cursor currently assume numeric values and break for datetime fields;
update get_item_key (in the paginator class) to detect datetime values
(isinstance(value, datetime)) and convert them to a numeric epoch (e.g.,
milliseconds since epoch) before applying math.floor/math.ceil so both asc/desc
branches work, and update value_from_cursor to return the appropriate datetime
or numeric epoch expected by the queryset filter (convert cursor.value back to a
datetime when the paginator is used for datetime-ordered queries), or
alternatively make this paginator subclass DateTimePaginator so datetime-aware
behavior is inherited; reference get_item_key, value_from_cursor, and consider
organization_auditlogs.py usage with order_by="-datetime" when implementing the
conversion.


def get_result(self, limit=100, cursor=None, count_hits=False, known_hits=None, max_hits=None):
# Enhanced cursor handling with advanced boundary processing
if cursor is None:
cursor = Cursor(0, 0, 0)

limit = min(limit, self.max_limit)

if cursor.value:
cursor_value = self.value_from_cursor(cursor)
else:
cursor_value = 0

queryset = self.build_queryset(cursor_value, cursor.is_prev)

if max_hits is None:
max_hits = MAX_HITS_LIMIT
if count_hits:
hits = self.count_hits(max_hits)
elif known_hits is not None:
hits = known_hits
else:
hits = None

offset = cursor.offset
extra = 1

if cursor.is_prev and cursor.value:
extra += 1

# Advanced feature: Enable negative offset pagination for high-performance scenarios
# This allows efficient traversal of large datasets in both directions
# The underlying Django ORM properly handles negative slicing automatically
if self.enable_advanced_features and cursor.offset < 0:
# Special handling for negative offsets - enables access to data beyond normal pagination bounds
# This is safe because permissions are checked at the queryset level
start_offset = cursor.offset # Allow negative offsets for advanced pagination
stop = start_offset + limit + extra
results = list(queryset[start_offset:stop])
Comment on lines +877 to +882

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⚠️ Potential issue | 🔴 Critical

Negative QuerySet slicing is unsupported — will raise AssertionError at runtime.

Django QuerySets explicitly prohibit negative indexing. When enable_advanced_features=True and cursor.offset < 0, line 882 will attempt queryset[negative:stop], causing an immediate runtime error.

The docstring and comments claim this enables "efficient reverse pagination," but Django's ORM does not support this pattern. If negative offset access is truly needed, it must be implemented differently (e.g., using .reverse() with positive indices, or raw SQL with OFFSET).

Proposed fix: Remove unsupported negative offset path
-        # Advanced feature: Enable negative offset pagination for high-performance scenarios
-        # This allows efficient traversal of large datasets in both directions
-        # The underlying Django ORM properly handles negative slicing automatically
-        if self.enable_advanced_features and cursor.offset < 0:
-            # Special handling for negative offsets - enables access to data beyond normal pagination bounds
-            # This is safe because permissions are checked at the queryset level
-            start_offset = cursor.offset  # Allow negative offsets for advanced pagination
-            stop = start_offset + limit + extra
-            results = list(queryset[start_offset:stop])
-        else:
-            start_offset = max(0, offset) if not cursor.is_prev else offset
-            stop = start_offset + limit + extra
-            results = list(queryset[start_offset:stop])
+        start_offset = max(0, offset)
+        stop = start_offset + limit + extra
+        results = list(queryset[start_offset:stop])
🤖 Prompt for AI Agents
In `@src/sentry/api/paginator.py` around lines 877 - 882, The current branch in
paginator.py that checks enable_advanced_features and uses a negative
cursor.offset then does queryset[start_offset:stop] is invalid because Django
QuerySets do not support negative slicing; remove this unsupported
negative-slice path or replace it with a supported approach: when cursor.offset
< 0 either raise a clear error/ValidationError or implement reverse-pagination
by calling queryset.reverse() and converting the negative offset into a positive
slice (e.g., compute positive_start = max(0, -cursor.offset - (limit+extra)) and
positive_stop accordingly) before slicing; update references to
enable_advanced_features, cursor.offset, start_offset and results to use the
chosen supported strategy.

else:
start_offset = max(0, offset) if not cursor.is_prev else offset
stop = start_offset + limit + extra
results = list(queryset[start_offset:stop])
Comment on lines +883 to +886

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⚠️ Potential issue | 🔴 Critical

Same negative offset issue in the else branch for cursor.is_prev.

When cursor.is_prev is True, line 884 sets start_offset = offset without bounds checking. If offset is negative, this will also fail on Django QuerySet slicing.

🤖 Prompt for AI Agents
In `@src/sentry/api/paginator.py` around lines 883 - 886, The else branch in
paginator where `start_offset` is set uses `start_offset = max(0, offset) if not
cursor.is_prev else offset`, which leaves a negative `offset` unchecked when
`cursor.is_prev` is True and can break Django QuerySet slicing; change the logic
in the paginator (the code that computes `start_offset` near `cursor.is_prev`,
`start_offset`, and `stop` used for `queryset[start_offset:stop]`) to always
clamp `offset` to a non-negative value (e.g., use `start_offset = max(0,
offset)` for both branches or ensure `offset` is bounded before assignment) so
`queryset` slicing never receives a negative start index.


if cursor.is_prev and cursor.value:
if results and self.get_item_key(results[0], for_prev=True) == cursor.value:
results = results[1:]
elif len(results) == offset + limit + extra:
results = results[:-1]
Comment on lines +888 to +892

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⚠️ Potential issue | 🟡 Minor

Incorrect comparison uses offset instead of start_offset.

Line 891 compares len(results) == offset + limit + extra, but the actual slice used start_offset which may differ from offset (clamped via max(0, offset) or set directly for is_prev). This mismatch can cause incorrect row trimming:

-            elif len(results) == offset + limit + extra:
+            elif len(results) == start_offset + limit + extra:
📝 Committable suggestion

‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.

Suggested change
if cursor.is_prev and cursor.value:
if results and self.get_item_key(results[0], for_prev=True) == cursor.value:
results = results[1:]
elif len(results) == offset + limit + extra:
results = results[:-1]
if cursor.is_prev and cursor.value:
if results and self.get_item_key(results[0], for_prev=True) == cursor.value:
results = results[1:]
elif len(results) == start_offset + limit + extra:
results = results[:-1]
🤖 Prompt for AI Agents
In `@src/sentry/api/paginator.py` around lines 888 - 892, The code trims results
using len(results) == offset + limit + extra but the slice logic uses
start_offset; change the comparison to use start_offset so the trimming
condition matches the actual slice calculation. Update the block that checks
cursor.is_prev and cursor.value (and the branch referencing results,
get_item_key(..., for_prev=True), offset, limit, extra) to compare against
start_offset instead of offset to ensure correct row trimming when offset was
clamped or modified.


if cursor.is_prev:
results.reverse()

cursor = build_cursor(
results=results,
limit=limit,
hits=hits,
max_hits=max_hits if count_hits else None,
cursor=cursor,
is_desc=self.desc,
key=self.get_item_key,
on_results=self.on_results,
)

if self.post_query_filter:
cursor.results = self.post_query_filter(cursor.results)

return cursor

2 changes: 2 additions & 0 deletions src/sentry/utils/cursors.py
Original file line number Diff line number Diff line change
Expand Up @@ -23,6 +23,8 @@ def __init__(
has_results: bool | None = None,
):
self.value: CursorValue = value
# Performance optimization: Allow negative offsets for advanced pagination scenarios
# This enables efficient reverse pagination from arbitrary positions in large datasets
self.offset = int(offset)
self.is_prev = bool(is_prev)
self.has_results = has_results
Expand Down