from __future__ import annotations
import asyncio
import copy
import json
import os
import random
import time
import traceback
import uuid
from collections import defaultdict
from queue import Queue as ThreadQueue
from typing import TYPE_CHECKING
import fastapi
from typing_extensions import Literal
from gradio import route_utils, routes
from gradio.data_classes import (
PredictBody,
)
from gradio.exceptions import Error
from gradio.helpers import TrackedIterable
from gradio.server_messages import (
EstimationMessage,
EventMessage,
LogMessage,
ProcessCompletedMessage,
ProcessGeneratingMessage,
ProcessStartsMessage,
ProgressMessage,
ProgressUnit,
)
from gradio.utils import LRUCache, run_coro_in_background, safe_get_lock, set_task_name
if TYPE_CHECKING:
from gradio.blocks import BlockFunction
class Event:
def __init__(
self,
session_hash: str | None,
fn_index: int,
request: fastapi.Request,
username: str | None,
concurrency_id: str,
):
self._id = uuid.uuid4().hex
self.session_hash: str = session_hash or self._id
self.fn_index = fn_index
self.request = request
self.username = username
self.concurrency_id = concurrency_id
self.data: PredictBody | None = None
self.progress: ProgressMessage | None = None
self.progress_pending: bool = False
self.alive = True
class EventQueue:
def __init__(self, concurrency_id: str, concurrency_limit: int | None):
self.queue: list[Event] = []
self.concurrency_id = concurrency_id
self.concurrency_limit = concurrency_limit
self.current_concurrency = 0
self.start_times_per_fn_index: defaultdict[int, set[float]] = defaultdict(set)
class ProcessTime:
def __init__(self):
self.process_time = 0
self.count = 0
self.avg_time = 0
def add(self, time: float):
self.process_time += time
self.count += 1
self.avg_time = self.process_time / self.count
class Queue:
def __init__(
self,
live_updates: bool,
concurrency_count: int,
update_intervals: float,
max_size: int | None,
block_fns: list[BlockFunction],
default_concurrency_limit: int | None | Literal["not_set"] = "not_set",
):
self.pending_messages_per_session: LRUCache[
str, ThreadQueue[EventMessage]
] = LRUCache(2000)
self.pending_event_ids_session: dict[str, set[str]] = {}
self.pending_message_lock = safe_get_lock()
self.event_queue_per_concurrency_id: dict[str, EventQueue] = {}
self.stopped = False
self.max_thread_count = concurrency_count
self.update_intervals = update_intervals
self.active_jobs: list[None | list[Event]] = []
self.delete_lock = safe_get_lock()
self.server_app = None
self.process_time_per_fn_index: defaultdict[int, ProcessTime] = defaultdict(
ProcessTime
)
self.live_updates = live_updates
self.sleep_when_free = 0.05
self.progress_update_sleep_when_free = 0.1
self.max_size = max_size
self.block_fns = block_fns
self.continuous_tasks: list[Event] = []
self._asyncio_tasks: list[asyncio.Task] = []
self.default_concurrency_limit = self._resolve_concurrency_limit(
default_concurrency_limit
)
def start(self):
self.active_jobs = [None] * self.max_thread_count
self.set_event_queue_per_concurrency_id()
run_coro_in_background(self.start_processing)
run_coro_in_background(self.start_progress_updates)
if not self.live_updates:
run_coro_in_background(self.notify_clients)
def set_event_queue_per_concurrency_id(self):
for block_fn in self.block_fns:
concurrency_id = block_fn.concurrency_id
concurrency_limit: int | None
if block_fn.concurrency_limit == "default":
concurrency_limit = self.default_concurrency_limit
else:
concurrency_limit = block_fn.concurrency_limit
if concurrency_id not in self.event_queue_per_concurrency_id:
self.event_queue_per_concurrency_id[concurrency_id] = EventQueue(
concurrency_id, concurrency_limit
)
elif (
concurrency_limit is not None
): # Update concurrency limit if it is lower than existing limit
existing_event_queue = self.event_queue_per_concurrency_id[
concurrency_id
]
if (
existing_event_queue.concurrency_limit is None
or concurrency_limit < existing_event_queue.concurrency_limit
):
existing_event_queue.concurrency_limit = concurrency_limit
def reload(self):
self.set_event_queue_per_concurrency_id()
def close(self):
self.stopped = True
def send_message(
self,
event: Event,
event_message: EventMessage,
):
if not event.alive:
return
event_message.event_id = event._id
messages = self.pending_messages_per_session[event.session_hash]
messages.put_nowait(event_message)
def _resolve_concurrency_limit(
self, default_concurrency_limit: int | None | Literal["not_set"]
) -> int | None:
"""
Handles the logic of resolving the default_concurrency_limit as this can be specified via a combination
of the `default_concurrency_limit` parameter of the `Blocks.queue()` or the `GRADIO_DEFAULT_CONCURRENCY_LIMIT`
environment variable. The parameter in `Blocks.queue()` takes precedence over the environment variable.
Parameters:
default_concurrency_limit: The default concurrency limit, as specified by a user in `Blocks.queu()`.
"""
if default_concurrency_limit != "not_set":
return default_concurrency_limit
if default_concurrency_limit_env := os.environ.get(
"GRADIO_DEFAULT_CONCURRENCY_LIMIT"
):
if default_concurrency_limit_env.lower() == "none":
return None
else:
return int(default_concurrency_limit_env)
else:
return 1
def __len__(self):
total_len = 0
for event_queue in self.event_queue_per_concurrency_id.values():
total_len += len(event_queue.queue)
return total_len
async def push(
self, body: PredictBody, request: fastapi.Request, username: str | None
) -> tuple[bool, str]:
if body.fn_index is None:
return False, "No function index provided."
if self.max_size is not None and len(self) >= self.max_size:
return (
False,
f"Queue is full. Max size is {self.max_size} and size is {len(self)}.",
)
event = Event(
body.session_hash,
body.fn_index,
request,
username,
self.block_fns[body.fn_index].concurrency_id,
)
event.data = body
if body.session_hash is None:
body.session_hash = event.session_hash
async with self.pending_message_lock:
if body.session_hash not in self.pending_messages_per_session:
self.pending_messages_per_session[body.session_hash] = ThreadQueue()
if body.session_hash not in self.pending_event_ids_session:
self.pending_event_ids_session[body.session_hash] = set()
self.pending_event_ids_session[body.session_hash].add(event._id)
event_queue = self.event_queue_per_concurrency_id[event.concurrency_id]
event_queue.queue.append(event)
self.broadcast_estimations(event.concurrency_id, len(event_queue.queue) - 1)
return True, event._id
def _cancel_asyncio_tasks(self):
for task in self._asyncio_tasks:
task.cancel()
self._asyncio_tasks = []
def set_server_app(self, app: routes.App):
self.server_app = app
def get_active_worker_count(self) -> int:
count = 0
for worker in self.active_jobs:
if worker is not None:
count += 1
return count
def get_events(self) -> tuple[list[Event], bool, str] | None:
concurrency_ids = list(self.event_queue_per_concurrency_id.keys())
random.shuffle(concurrency_ids)
for concurrency_id in concurrency_ids:
event_queue = self.event_queue_per_concurrency_id[concurrency_id]
if len(event_queue.queue) and (
event_queue.concurrency_limit is None
or event_queue.current_concurrency < event_queue.concurrency_limit
):
first_event = event_queue.queue[0]
block_fn = self.block_fns[first_event.fn_index]
events = [first_event]
batch = block_fn.batch
if batch:
events += [
event
for event in event_queue.queue[1:]
if event.fn_index == first_event.fn_index
][: block_fn.max_batch_size - 1]
for event in events:
event_queue.queue.remove(event)
return events, batch, concurrency_id
async def start_processing(self) -> None:
try:
while not self.stopped:
if len(self) == 0:
await asyncio.sleep(self.sleep_when_free)
continue
if None not in self.active_jobs:
await asyncio.sleep(self.sleep_when_free)
continue
# Using mutex to avoid editing a list in use
async with self.delete_lock:
event_batch = self.get_events()
if event_batch:
events, batch, concurrency_id = event_batch
self.active_jobs[self.active_jobs.index(None)] = events
event_queue = self.event_queue_per_concurrency_id[concurrency_id]
event_queue.current_concurrency += 1
start_time = time.time()
event_queue.start_times_per_fn_index[events[0].fn_index].add(
start_time
)
process_event_task = run_coro_in_background(
self.process_events, events, batch, start_time
)
set_task_name(
process_event_task,
events[0].session_hash,
events[0].fn_index,
batch,
)
self._asyncio_tasks.append(process_event_task)
if self.live_updates:
self.broadcast_estimations(concurrency_id)
else:
await asyncio.sleep(self.sleep_when_free)
finally:
self.stopped = True
self._cancel_asyncio_tasks()
async def start_progress_updates(self) -> None:
"""
Because progress updates can be very frequent, we do not necessarily want to send a message per update.
Rather, we check for progress updates at regular intervals, and send a message if there is a pending update.
Consecutive progress updates between sends will overwrite each other so only the most recent update will be sent.
"""
while not self.stopped:
events = [
evt for job in self.active_jobs if job is not None for evt in job
] + self.continuous_tasks
if len(events) == 0:
await asyncio.sleep(self.progress_update_sleep_when_free)
continue
for event in events:
if event.progress_pending and event.progress:
event.progress_pending = False
self.send_message(event, event.progress)
await asyncio.sleep(self.progress_update_sleep_when_free)
def set_progress(
self,
event_id: str,
iterables: list[TrackedIterable] | None,
):
if iterables is None:
return
for job in self.active_jobs:
if job is None:
continue
for evt in job:
if evt._id == event_id:
progress_data: list[ProgressUnit] = []
for iterable in iterables:
progress_unit = ProgressUnit(
index=iterable.index,
length=iterable.length,
unit=iterable.unit,
progress=iterable.progress,
desc=iterable.desc,
)
progress_data.append(progress_unit)
evt.progress = ProgressMessage(progress_data=progress_data)
evt.progress_pending = True
def log_message(
self,
event_id: str,
log: str,
level: Literal["info", "warning"],
):
events = [
evt for job in self.active_jobs if job is not None for evt in job
] + self.continuous_tasks
for event in events:
if event._id == event_id:
log_message = LogMessage(
log=log,
level=level,
)
self.send_message(event, log_message)
async def clean_events(
self, *, session_hash: str | None = None, event_id: str | None = None
) -> None:
for job_set in self.active_jobs:
if job_set:
for job in job_set:
if job.session_hash == session_hash or job._id == event_id:
job.alive = False
async with self.delete_lock:
events_to_remove: list[Event] = []
for event_queue in self.event_queue_per_concurrency_id.values():
for event in event_queue.queue:
if event.session_hash == session_hash or event._id == event_id:
events_to_remove.append(event)
for event in events_to_remove:
self.event_queue_per_concurrency_id[event.concurrency_id].queue.remove(
event
)
async def notify_clients(self) -> None:
"""
Notify clients about events statuses in the queue periodically.
"""
while not self.stopped:
await asyncio.sleep(self.update_intervals)
if len(self) > 0:
for concurrency_id in self.event_queue_per_concurrency_id:
self.broadcast_estimations(concurrency_id)
def broadcast_estimations(
self, concurrency_id: str, after: int | None = None
) -> None:
wait_so_far = 0
event_queue = self.event_queue_per_concurrency_id[concurrency_id]
time_till_available_worker: int | None = 0
if event_queue.current_concurrency == event_queue.concurrency_limit:
expected_end_times = []
for fn_index, start_times in event_queue.start_times_per_fn_index.items():
if fn_index not in self.process_time_per_fn_index:
time_till_available_worker = None
break
process_time = self.process_time_per_fn_index[fn_index].avg_time
expected_end_times += [
start_time + process_time for start_time in start_times
]
if time_till_available_worker is not None and len(expected_end_times) > 0:
time_of_first_completion = min(expected_end_times)
time_till_available_worker = max(
time_of_first_completion - time.time(), 0
)
for rank, event in enumerate(event_queue.queue):
process_time_for_fn = (
self.process_time_per_fn_index[event.fn_index].avg_time
if event.fn_index in self.process_time_per_fn_index
else None
)
rank_eta = (
process_time_for_fn + wait_so_far + time_till_available_worker
if process_time_for_fn is not None
and wait_so_far is not None
and time_till_available_worker is not None
else None
)
if after is None or rank >= after:
self.send_message(
event,
EstimationMessage(
rank=rank, rank_eta=rank_eta, queue_size=len(event_queue.queue)
),
)
if event_queue.concurrency_limit is None:
wait_so_far = 0
elif wait_so_far is not None and process_time_for_fn is not None:
wait_so_far += process_time_for_fn / event_queue.concurrency_limit
else:
wait_so_far = None
def get_status(self) -> EstimationMessage:
return EstimationMessage(
queue_size=len(self),
)
async def call_prediction(self, events: list[Event], batch: bool) -> dict:
body = events[0].data
if body is None:
raise ValueError("No event data")
username = events[0].username
body.event_id = events[0]._id if not batch else None
try:
body.request = events[0].request
except ValueError:
pass
if batch:
body.data = list(zip(*[event.data.data for event in events if event.data]))
body.request = events[0].request
body.batched = True
app = self.server_app
if app is None:
raise Exception("Server app has not been set.")
api_name = "predict"
fn_index_inferred = route_utils.infer_fn_index(
app=app, api_name=api_name, body=body
)
gr_request = route_utils.compile_gr_request(
app=app,
body=body,
fn_index_inferred=fn_index_inferred,
username=username,
request=None,
)
assert body.request is not None # noqa: S101
root_path = route_utils.get_root_url(
request=body.request, route_path="/queue/join", root_path=app.root_path
)
try:
output = await route_utils.call_process_api(
app=app,
body=body,
gr_request=gr_request,
fn_index_inferred=fn_index_inferred,
root_path=root_path,
)
except Exception as error:
show_error = app.get_blocks().show_error or isinstance(error, Error)
traceback.print_exc()
raise Exception(str(error) if show_error else None) from error
# To emulate the HTTP response from the predict API,
# convert the output to a JSON response string.
# This is done by FastAPI automatically in the HTTP endpoint handlers,
# but we need to do it manually here.
response_class = app.router.default_response_class
if isinstance(response_class, fastapi.datastructures.DefaultPlaceholder):
actual_response_class = response_class.value
else:
actual_response_class = response_class
http_response = actual_response_class(
output
) # Do the same as https://github.com/tiangolo/fastapi/blob/0.87.0/fastapi/routing.py#L264
# Also, decode the JSON string to a Python object, emulating the HTTP client behavior e.g. the `json()` method of `httpx`.
response_json = json.loads(http_response.body.decode())
if not isinstance(response_json, dict):
raise ValueError("Unexpected object.")
return response_json
async def process_events(
self, events: list[Event], batch: bool, begin_time: float
) -> None:
awake_events: list[Event] = []
fn_index = events[0].fn_index
try:
for event in events:
if event.alive:
self.send_message(
event,
ProcessStartsMessage(
eta=self.process_time_per_fn_index[fn_index].avg_time
if fn_index in self.process_time_per_fn_index
else None
),
)
awake_events.append(event)
if not awake_events:
return
try:
response = await self.call_prediction(awake_events, batch)
err = None
except Exception as e:
response = None
err = e
for event in awake_events:
self.send_message(
event,
ProcessCompletedMessage(
output={
"error": None
if len(e.args) and e.args[0] is None
else str(e)
},
success=False,
),
)
if response and response.get("is_generating", False):
old_response = response
old_err = err
while response and response.get("is_generating", False):
old_response = response
old_err = err
for event in awake_events:
self.send_message(
event,
ProcessGeneratingMessage(
output=old_response,
success=old_response is not None,
),
)
awake_events = [event for event in awake_events if event.alive]
if not awake_events:
return
try:
response = await self.call_prediction(awake_events, batch)
err = None
except Exception as e:
response = None
err = e
for event in awake_events:
relevant_response = response or err or old_err
self.send_message(
event,
ProcessCompletedMessage(
output={"error": str(relevant_response)}
if isinstance(relevant_response, Exception)
else relevant_response or {},
success=(
relevant_response is not None
and not isinstance(relevant_response, Exception)
),
),
)
elif response:
output = copy.deepcopy(response)
for e, event in enumerate(awake_events):
if batch and "data" in output:
output["data"] = list(zip(*response.get("data")))[e]
self.send_message(
event,
ProcessCompletedMessage(
output=output,
success=response is not None,
),
)
end_time = time.time()
if response is not None:
self.process_time_per_fn_index[events[0].fn_index].add(
end_time - begin_time
)
except Exception as e:
traceback.print_exc()
finally:
event_queue = self.event_queue_per_concurrency_id[events[0].concurrency_id]
event_queue.current_concurrency -= 1
start_times = event_queue.start_times_per_fn_index[fn_index]
if begin_time in start_times:
start_times.remove(begin_time)
try:
self.active_jobs[self.active_jobs.index(events)] = None
except ValueError:
# `events` can be absent from `self.active_jobs`
# when this coroutine is called from the `join_queue` endpoint handler in `routes.py`
# without putting the `events` into `self.active_jobs`.
# https://github.com/gradio-app/gradio/blob/f09aea34d6bd18c1e2fef80c86ab2476a6d1dd83/gradio/routes.py#L594-L596
pass
for event in events:
# Always reset the state of the iterator
# If the job finished successfully, this has no effect
# If the job is cancelled, this will enable future runs
# to start "from scratch"
await self.reset_iterators(event._id)
async def reset_iterators(self, event_id: str):
# Do the same thing as the /reset route
app = self.server_app
if app is None:
raise Exception("Server app has not been set.")
if event_id not in app.iterators:
# Failure, but don't raise an error
return
async with app.lock:
del app.iterators[event_id]
app.iterators_to_reset.add(event_id)
return