haiku.rag/haiku_rag_slim/haiku/rag/sandbox/sandbox.py
Yiorgis Gozadinos d1ad14f44b
Point the limit comments at the right limits
_session_limits still called the session budget the backstop for code that
computes, which stopped being true when the pool gained a request_timeout in the
same commit. The watchdog kills such a call at code_timeout, so it can never
spend a budget of code_timeout * max_executions. The docstring now names the two
per-call limits and claims neither.

The crash test said the discard prevents a RuntimeError escaping execute(). The
handler catches RuntimeError too, so without the discard every later call
returns a failed result instead.

Name MemoryFile's missing write hook as the reason metadata.json takes a reader
and a deny pair. Drop the clause in the CHANGELOG that narrated how the old
overrun accumulated.
2026-07-28 19:11:37 +03:00

554 lines
22 KiB
Python

import asyncio
import json
import os
from collections.abc import AsyncIterator, Callable, Coroutine
from contextlib import asynccontextmanager, suppress
from dataclasses import dataclass
from pathlib import Path
from typing import TYPE_CHECKING, Any, Literal
import pydantic_monty
from pydantic_monty import (
AsyncMonty,
AsyncMontySession,
CallbackFile,
OSAccess,
ResourceLimits,
)
from haiku.rag.config.models import AppConfig
from haiku.rag.sandbox.dependencies import AnalysisContext
from haiku.rag.store.models.chunk import SearchResult
from haiku.rag.store.models.document_item import PICTURE_REF_PREFIX, DocumentItem
if TYPE_CHECKING:
from pathlib import PurePosixPath
from haiku.rag.client import HaikuRAG
@dataclass
class SandboxResult:
"""Result of executing code in the sandbox."""
stdout: str
stderr: str
success: bool
def _build_toc(
items: list["DocumentItem"],
chunk_index: dict[str, list[str]],
) -> list[dict[str, Any]]:
"""Build a nested section tree from items in position order.
Each ``section_header`` with ``heading_level > 0`` becomes a node. Nesting
follows the explicit levels: a header pops the stack until the top is at
a strictly shallower level, then becomes a child of that top (or a root).
``item_range = [position, end_exclusive]`` where ``end_exclusive`` is the
position of the next header whose level is the same or shallower (i.e.
the next sibling or ancestor that ends this section), or the total item
count if no such header exists.
``chunk_ids`` aggregates the chunks covered by all items in the section's
``item_range`` (deduped, order preserved). Pass directly to ``cite()`` to
ground a section-scoped answer without a corpus-wide ``search()`` call.
Items without a section_header label (or with ``heading_level == 0``) are
skipped. When all section_headers carry the same level the output is a
flat sibling list (see docling-project/docling#2121 for an upstream case
where every PDF section_header is emitted at level=1).
"""
# Defensive: every consumer is supposed to pass items in position order,
# but the end_exclusive lookahead below silently miscomputes section
# boundaries if it's not — better to sort once than trust the caller.
items = sorted(items, key=lambda i: i.position)
headers: list[DocumentItem] = [
i for i in items if i.label == "section_header" and i.heading_level > 0
]
if not headers:
return []
total = max((i.position for i in items), default=-1) + 1
items_by_position: dict[int, DocumentItem] = {i.position: i for i in items}
ends: list[int] = []
for idx, h in enumerate(headers):
end = total
for j in range(idx + 1, len(headers)):
if headers[j].heading_level <= h.heading_level:
end = headers[j].position
break
ends.append(end)
roots: list[dict[str, Any]] = []
stack: list[tuple[int, dict[str, Any]]] = []
for h, end in zip(headers, ends, strict=True):
seen: set[str] = set()
chunk_ids: list[str] = []
for pos in range(h.position, end):
item = items_by_position.get(pos)
if item is None:
continue
for cid in chunk_index.get(item.self_ref, []):
if cid not in seen:
seen.add(cid)
chunk_ids.append(cid)
node: dict[str, Any] = {
"self_ref": h.self_ref,
"level": h.heading_level,
"title": h.text,
"page_numbers": list(h.page_numbers),
"item_range": [h.position, end],
"chunk_ids": chunk_ids,
"children": [],
}
while stack and stack[-1][0] >= h.heading_level:
stack.pop()
(stack[-1][1]["children"] if stack else roots).append(node)
stack.append((h.heading_level, node))
return roots
class Sandbox:
"""Execute code in a sandboxed Python interpreter.
Uses pydantic-monty, a minimal secure Python interpreter written in Rust.
The interpreter runs in a subprocess worker checked out of an ``AsyncMonty``
pool. External functions (search, list_documents) are called by Monty code
using ``await`` and resolved asynchronously on the host. Documents are
exposed via a virtual filesystem at ``/documents/{id}/``.
The session persists across ``execute()`` calls within the same Sandbox
instance — variables carry over. Call ``close()`` to return the worker to
the pool and shut the pool down.
sandbox = Sandbox(db_path, config, context)
result = await sandbox.execute("x = await search('query')")
result = await sandbox.execute("print(x[0]['content'])") # x persists
await sandbox.close()
All database access runs on the event loop that drives ``execute()``. Monty's
file callbacks are synchronous and run off that loop while ``feed_run`` is
awaited, so they bridge back to it via ``run_coroutine_threadsafe`` without
deadlocking. When a ``rag`` connection is supplied it is used for every read,
so an analysis run drives a single connection on a single loop; otherwise
each read opens an ephemeral read-only connection.
"""
_db_path: Path
_config: AppConfig
_context: AnalysisContext
_rag: "HaikuRAG | None"
_lock: "asyncio.Lock | None"
_search_results: "list[SearchResult]"
_doc_items: dict[str, list["DocumentItem"]]
_doc_chunk_index: dict[str, dict[str, list[str]]]
_items_jsonl_cache: dict[str, str]
_toc_json_cache: dict[str, str]
_pool: AsyncMonty | None
_session: AsyncMontySession | None
_vfs: OSAccess | None
_loop: asyncio.AbstractEventLoop | None
_deadline: float | None
def __init__(
self,
db_path: Path,
config: AppConfig,
context: AnalysisContext,
rag: "HaikuRAG | None" = None,
lock: "asyncio.Lock | None" = None,
):
self._db_path = db_path
self._config = config
self._context = context
self._rag = rag
self._lock = lock
self._search_results = []
self._doc_items = {}
self._doc_chunk_index = {}
self._items_jsonl_cache = {}
self._toc_json_cache = {}
self._pool = None
self._session = None
self._vfs = None
self._loop = None
self._deadline = None
@asynccontextmanager
async def _connection(self) -> "AsyncIterator[HaikuRAG]":
"""Yield the shared connection (serialized by the lock), or an ephemeral
read-only one. The lock guards the whole block so a read's awaits cannot
interleave with another task's operation on the same connection."""
if self._rag is not None:
if self._lock is not None:
async with self._lock:
yield self._rag
else:
yield self._rag
return
from haiku.rag.client import HaikuRAG
async with HaikuRAG(self._db_path, config=self._config, read_only=True) as rag:
yield rag
def _run_on_loop(self, coro: Coroutine[Any, Any, Any]) -> Any:
"""Run a coroutine on the execute() loop from a synchronous callback.
Called off the loop while ``feed_run`` is awaited, so scheduling onto it
and blocking for the result is safe.
Blocking here suspends the worker, and Monty checks its duration budget
between interpreter steps, so it cannot check while a read is in flight.
Enforce the budget before starting another read, or code that reads in a
loop overruns it by however long the outstanding reads take. Raising from
inside the callback answers the worker's suspension, which keeps the
session usable — cancelling ``feed_run`` from outside does not, and wedges
the protocol.
"""
assert self._loop is not None, (
"VFS reads happen during execute(); the loop must be captured first."
)
if self._deadline is not None and self._loop.time() > self._deadline:
coro.close()
raise TimeoutError(
"time limit exceeded: no further document reads after "
f"{self._config.analysis.code_timeout}s"
)
return asyncio.run_coroutine_threadsafe(coro, self._loop).result()
async def _discard_session(self) -> None:
"""Drop a session whose worker is gone.
The session object is unusable once its worker dies: it answers every
later call with ``RuntimeError: this checkout has already been
finished``. Clearing it makes ``_ensure_initialized`` check out a
replacement, at the cost of the variables the dead worker held.
"""
session, self._session = self._session, None
if session is not None:
with suppress(Exception):
await session.__aexit__(None, None, None)
async def close(self) -> None:
"""Return the worker to the pool and shut the pool down. Idempotent."""
if self._session is not None:
await self._session.__aexit__(None, None, None)
self._session = None
if self._pool is not None:
await self._pool.__aexit__(None, None, None)
self._pool = None
def _build_external_functions(self) -> dict[str, Any]:
"""Build async external functions for the Monty interpreter."""
context = self._context
async def search(query: str, limit: int = 10) -> list[dict[str, Any]]:
# Picture bytes are deliberately not attached to in-code search
# results: the Monty interpreter has no PIL/base64/hashlib, so the
# agent's Python can't do anything with them. The driving model
# gets figures through the top-level `search` tool when the
# question is visual; in-code search is for structural work.
async with self._connection() as rag:
results = await rag.search(query, limit=limit, filter=context.filter)
expanded = await rag.expand_context(results)
self._search_results.extend(expanded)
out: list[dict[str, Any]] = []
for r in expanded:
picture_refs = [
ref for ref in r.doc_item_refs if ref.startswith(PICTURE_REF_PREFIX)
]
out.append(
{
"chunk_id": r.chunk_id,
"content": r.content,
"document_id": r.document_id,
"document_title": r.document_title,
"document_uri": r.document_uri,
"score": r.score,
"page_numbers": r.page_numbers,
"headings": r.headings,
"doc_item_refs": r.doc_item_refs,
"labels": r.labels,
"picture_refs": picture_refs,
}
)
return out
async def list_documents() -> list[dict[str, Any]]:
async with self._connection() as rag:
docs = await rag.list_documents(filter=context.filter)
return [
{
"id": d.id,
"title": d.title,
"uri": d.uri,
"created_at": str(d.created_at),
}
for d in docs
]
return {
"search": search,
"list_documents": list_documents,
}
async def _build_vfs(self) -> OSAccess:
"""Build the virtual filesystem with document data.
Mounts per-document directories with:
- metadata.json: CallbackFile (eager, small)
- content.txt: CallbackFile (lazy, can be large)
- items.jsonl: CallbackFile (lazy, bulk-cached)
- toc.json: CallbackFile (lazy, bulk-cached)
"""
files: list[CallbackFile] = []
def _deny_write(_path: "PurePosixPath", _content: str | bytes) -> None:
raise PermissionError(f"Document files are read-only: {_path}")
async with self._connection() as rag:
docs = await rag.list_documents(filter=self._context.filter)
doc_titles = {doc.id: doc.title for doc in docs if doc.id}
sandbox = self
def _get_items(did: str) -> list[DocumentItem]:
"""Fetch items for one doc, cached on the sandbox."""
cached = sandbox._doc_items.get(did)
if cached is not None:
return cached
async def _fetch() -> list[DocumentItem]:
async with sandbox._connection() as rag:
return await rag.document_item_repository.get_all_items(did)
items = sandbox._run_on_loop(_fetch())
sandbox._doc_items[did] = items
return items
def _get_chunk_index(did: str) -> dict[str, list[str]]:
"""Fetch the self_ref → chunk_ids index for one doc, cached."""
cached = sandbox._doc_chunk_index.get(did)
if cached is not None:
return cached
async def _fetch() -> dict[str, list[str]]:
async with sandbox._connection() as rag:
index = (
await rag.chunk_repository.get_chunk_ids_by_self_ref_grouped(
[did]
)
)
return index.get(did, {})
chunk_index = sandbox._run_on_loop(_fetch())
sandbox._doc_chunk_index[did] = chunk_index
return chunk_index
def _make_items_reader(
did: str,
) -> Callable[["PurePosixPath"], str]:
def read_items(_path: "PurePosixPath") -> str:
cached = sandbox._items_jsonl_cache.get(did)
if cached is not None:
return cached
items = _get_items(did)
chunk_index = _get_chunk_index(did)
jsonl = "\n".join(
json.dumps(
{
"self_ref": item.self_ref,
"label": item.label,
"text": item.text,
"page_numbers": item.page_numbers,
"heading_level": item.heading_level,
"chunk_ids": chunk_index.get(item.self_ref, []),
},
ensure_ascii=False,
)
for item in items
)
sandbox._items_jsonl_cache[did] = jsonl
return jsonl
return read_items
def _make_toc_reader(
did: str,
) -> Callable[["PurePosixPath"], str]:
def read_toc(_path: "PurePosixPath") -> str:
cached = sandbox._toc_json_cache.get(did)
if cached is not None:
return cached
items = _get_items(did)
chunk_index = _get_chunk_index(did)
toc = json.dumps(
{
"doc_id": did,
"title": doc_titles.get(did),
"tree": _build_toc(items, chunk_index),
},
ensure_ascii=False,
)
sandbox._toc_json_cache[did] = toc
return toc
return read_toc
for doc in docs:
if not doc.id: # pragma: no cover - stored rows always carry an id
continue
doc_id: str = doc.id
doc_dir = f"/documents/{doc_id}"
metadata = json.dumps(
{
"id": doc_id,
"title": doc.title,
"uri": doc.uri,
"created_at": str(doc.created_at),
},
ensure_ascii=False,
)
# MemoryFile has no write hook, so metadata.json goes through the
# same read and deny pair as the rest. Its content is already built.
files.append(
CallbackFile(
f"{doc_dir}/metadata.json",
read=lambda _path, text=metadata: text,
write=_deny_write,
)
)
def _make_content_reader(
did: str,
) -> Callable[["PurePosixPath"], str]:
def read_content(_path: "PurePosixPath") -> str:
async def _fetch() -> str:
async with sandbox._connection() as rag:
content = await rag.document_repository.get_content(did)
return content or ""
return sandbox._run_on_loop(_fetch())
return read_content
files.append(
CallbackFile(
f"{doc_dir}/content.txt",
read=_make_content_reader(doc_id),
write=_deny_write,
)
)
files.append(
CallbackFile(
f"{doc_dir}/items.jsonl",
read=_make_items_reader(doc_id),
write=_deny_write,
)
)
# HAIKU_RAG_DISABLE_TOC is an evaluation-time toggle for measuring
# whether toc.json's outline view earns its place in the VFS.
# Production callers should leave it unset.
if not os.environ.get("HAIKU_RAG_DISABLE_TOC"):
files.append(
CallbackFile(
f"{doc_dir}/toc.json",
read=_make_toc_reader(doc_id),
write=_deny_write,
)
)
return OSAccess(files)
def _session_limits(self) -> ResourceLimits:
"""Resource limits for the worker session.
Monty spends ``max_duration_secs`` across the session's whole life, and
the session is reused so variables persist between calls. Budget it for
the run rather than for one call, or the first slow call starves every
later one. ``code_timeout`` is enforced per call elsewhere: the read
deadline in ``_run_on_loop`` bounds a call that reads, and the pool's
``request_timeout`` bounds one that computes.
"""
analysis = self._config.analysis
return {"max_duration_secs": analysis.code_timeout * analysis.max_executions}
async def _ensure_initialized(self) -> tuple[AsyncMontySession, OSAccess]:
"""Check out a worker session and build the VFS on first use."""
if self._vfs is None:
self._vfs = await self._build_vfs()
if self._pool is None:
# The watchdog counts only time the worker spends running code, so a
# read that blocks the worker never trips it. That leaves the two
# limits disjoint: this one bounds a call that computes, and the read
# deadline bounds a call that reads.
pool = AsyncMonty(request_timeout=self._config.analysis.code_timeout)
await pool.__aenter__()
self._pool = pool
if self._session is None:
session = self._pool.checkout(limits=self._session_limits())
await session.__aenter__()
self._session = session
assert self._session is not None and self._vfs is not None
return self._session, self._vfs
async def execute(self, code: str) -> SandboxResult:
"""Execute Python code in the Monty worker session.
Variables persist across calls within the same Sandbox instance.
"""
# Monty's synchronous file callbacks bridge DB reads back to this loop.
self._loop = asyncio.get_running_loop()
self._deadline = self._loop.time() + self._config.analysis.code_timeout
session, vfs = await self._ensure_initialized()
external_fns = self._build_external_functions()
stdout_lines: list[str] = []
def print_callback( # pragma: no cover - runs on Monty's worker thread
_stream: Literal["stdout", "stderr"], text: str
) -> None:
stdout_lines.append(text)
max_chars = self._config.analysis.max_output_chars
try:
output = await session.feed_run(
code,
external_lookup=external_fns,
print_callback=print_callback,
os=vfs,
)
except (pydantic_monty.MontyError, RuntimeError) as e:
stdout = "".join(stdout_lines)
if len(stdout) > max_chars:
stdout = stdout[:max_chars] + "\n... (output truncated)"
stderr = str(e)
# A crash kills the worker, and a protocol error leaves it out of
# step. Both poison the session. Bad user code does not.
if isinstance(e, pydantic_monty.MontyCrashedError | RuntimeError):
await self._discard_session()
stderr = (
f"{stderr}\n\nThe interpreter restarted. Variables from "
"earlier calls are gone."
)
return SandboxResult(stdout=stdout, stderr=stderr, success=False)
stdout = "".join(stdout_lines)
if output is not None:
stdout_with_output = f"{stdout}{output}" if stdout else str(output)
else:
stdout_with_output = stdout
if len(stdout_with_output) > max_chars:
stdout_with_output = (
stdout_with_output[:max_chars] + "\n... (output truncated)"
)
return SandboxResult(stdout=stdout_with_output, stderr="", success=True)