def __init__(self, script_name):
"""Initializes the ScriptRunner for the given script_name"""
# DeltaGenerator deltas will be enqueued into self.report_queue.
self.report_queue = ReportQueue()
def enqueue_fn(msg):
self.report_queue.enqueue(msg)
self.maybe_handle_execution_control_request()
self.script_request_queue = ScriptRequestQueue()
script_path = os.path.join(os.path.dirname(__file__), "test_data",
script_name)
super(TestScriptRunner, self).__init__(
session_id="test session id",
report=Report(script_path, "test command line"),
enqueue_forward_msg=enqueue_fn,
client_state=ClientState(),
request_queue=self.script_request_queue,
)
# Accumulates uncaught exceptions thrown by our run thread.
self.script_thread_exceptions = []
# Accumulates all ScriptRunnerEvents emitted by us.
self.events = []
def record_event(event, **kwargs):
self.events.append(event)
self.on_event.connect(record_event, weak=False)
def __init__(self, ioloop, script_path, command_line,
uploaded_file_manager):
"""Initialize the ReportSession.
Parameters
----------
ioloop : tornado.ioloop.IOLoop
The Tornado IOLoop that we're running within.
script_path : str
Path of the Python file from which this report is generated.
command_line : str
Command line as input by the user.
uploaded_file_manager : UploadedFileManager
The server's UploadedFileManager.
"""
# Each ReportSession has a unique string ID.
self.id = str(uuid.uuid4())
self._ioloop = ioloop
self._report = Report(script_path, command_line)
self._uploaded_file_mgr = uploaded_file_manager
self._state = ReportSessionState.REPORT_NOT_RUNNING
# Need to remember the client state here because when a script reruns
# due to the source code changing we need to pass in the previous client state.
self._client_state = ClientState()
self._local_sources_watcher = LocalSourcesWatcher(
self._report, self._on_source_file_changed)
self._stop_config_listener = config.on_config_parsed(
self._on_source_file_changed, force_connect=True)
self._storage = None
self._maybe_reuse_previous_run = False
self._run_on_save = config.get_option("server.runOnSave")
# The ScriptRequestQueue is the means by which we communicate
# with the active ScriptRunner.
self._script_request_queue = ScriptRequestQueue()
self._scriptrunner = None
# This needs to be lazily imported to avoid a dependency cycle.
from streamlit.state.session_state import SessionState
self._session_state = SessionState()
LOGGER.debug("ReportSession initialized (id=%s)", self.id)
def test_dequeue(self):
"""Test that we can enqueue and dequeue on different threads"""
queue = ScriptRequestQueue()
# This should return immediately
self.assertEqual((None, None), queue.dequeue())
lock = Lock()
dequeued_evt = [None]
def get_event():
with lock:
return dequeued_evt[0]
def set_event(value):
with lock:
dequeued_evt[0] = value
def do_dequeue():
event = None
while event is None:
event, _ = queue.dequeue()
set_event(event)
thread = Thread(target=do_dequeue, name="test_dequeue")
thread.start()
self.assertIsNone(get_event())
queue.enqueue(ScriptRequest.STOP)
time.sleep(0.1)
self.assertEqual(ScriptRequest.STOP, get_event())
thread.join(timeout=0.25)
self.assertFalse(thread.is_alive())
def __init__(self, script_name):
"""Initializes the ScriptRunner for the given script_name"""
# DeltaGenerator deltas will be enqueued into self.forward_msg_queue.
self.forward_msg_queue = ForwardMsgQueue()
self.script_request_queue = ScriptRequestQueue()
main_script_path = os.path.join(os.path.dirname(__file__), "test_data",
script_name)
super(TestScriptRunner, self).__init__(
session_id="test session id",
session_data=SessionData(main_script_path, "test command line"),
enqueue_forward_msg=self.forward_msg_queue.enqueue,
client_state=ClientState(),
session_state=SessionState(),
request_queue=self.script_request_queue,
uploaded_file_mgr=UploadedFileManager(),
)
# Accumulates uncaught exceptions thrown by our run thread.
self.script_thread_exceptions = []
# Accumulates all ScriptRunnerEvents emitted by us.
self.events: List[ScriptRunnerEvent] = []
self.event_data: List[Any] = []
def record_event(sender: Optional[ScriptRunner],
event: ScriptRunnerEvent, **kwargs):
# Assert that we're not getting unexpected `sender` params
# from ScriptRunner.on_event
assert (sender is None
or sender == self), "Unexpected ScriptRunnerEvent sender!"
self.events.append(event)
self.event_data.append(kwargs)
self.on_event.connect(record_event, weak=False)
class TestScriptRunner(ScriptRunner):
"""Subclasses ScriptRunner to provide some testing features."""
def __init__(self, script_name):
"""Initializes the ScriptRunner for the given script_name"""
# DeltaGenerator deltas will be enqueued into self.report_queue.
self.report_queue = ReportQueue()
def enqueue_fn(msg):
self.report_queue.enqueue(msg)
self.maybe_handle_execution_control_request()
self.script_request_queue = ScriptRequestQueue()
script_path = os.path.join(os.path.dirname(__file__), "test_data",
script_name)
super(TestScriptRunner, self).__init__(
session_id="test session id",
report=Report(script_path, "test command line"),
enqueue_forward_msg=enqueue_fn,
client_state=ClientState(),
request_queue=self.script_request_queue,
)
# Accumulates uncaught exceptions thrown by our run thread.
self.script_thread_exceptions = []
# Accumulates all ScriptRunnerEvents emitted by us.
self.events = []
def record_event(event, **kwargs):
self.events.append(event)
self.on_event.connect(record_event, weak=False)
def enqueue_rerun(self, argv=None, widget_states=None):
self.script_request_queue.enqueue(
ScriptRequest.RERUN, RerunData(widget_states=widget_states))
def enqueue_stop(self):
self.script_request_queue.enqueue(ScriptRequest.STOP)
def enqueue_shutdown(self):
self.script_request_queue.enqueue(ScriptRequest.SHUTDOWN)
def _process_request_queue(self):
try:
super(TestScriptRunner, self)._process_request_queue()
except BaseException as e:
self.script_thread_exceptions.append(e)
def _run_script(self, rerun_data):
self.report_queue.clear()
super(TestScriptRunner, self)._run_script(rerun_data)
def join(self):
"""Joins the run thread, if it was started"""
if self._script_thread is not None:
self._script_thread.join()
def clear_deltas(self):
"""Clear all delta messages from our ReportQueue"""
self.report_queue.clear()
def deltas(self) -> List[Delta]:
"""Return the delta messages in our ReportQueue"""
return [
msg.delta for msg in self.report_queue._queue
if msg.HasField("delta")
]
def elements(self) -> List[Element]:
"""Return the delta.new_element messages in our ReportQueue."""
return [delta.new_element for delta in self.deltas()]
def text_deltas(self) -> List[str]:
"""Return the string contents of text deltas in our ReportQueue"""
return [
element.text.body for element in self.elements()
if element.WhichOneof("type") == "text"
]
def get_widget_id(self, widget_type, label):
"""Returns the id of the widget with the specified type and label"""
for delta in self.deltas():
new_element = getattr(delta, "new_element", None)
widget = getattr(new_element, widget_type, None)
widget_label = getattr(widget, "label", None)
if widget_label == label:
return widget.id
return None
class ReportSession(object):
"""
Contains session data for a single "user" of an active report
(that is, a connected browser tab).
Each ReportSession has its own Report, root DeltaGenerator, ScriptRunner,
and widget state.
A ReportSession is attached to each thread involved in running its Report.
"""
def __init__(self, ioloop, script_path, command_line,
uploaded_file_manager):
"""Initialize the ReportSession.
Parameters
----------
ioloop : tornado.ioloop.IOLoop
The Tornado IOLoop that we're running within.
script_path : str
Path of the Python file from which this report is generated.
command_line : str
Command line as input by the user.
uploaded_file_manager : UploadedFileManager
The server's UploadedFileManager.
"""
# Each ReportSession has a unique string ID.
self.id = str(uuid.uuid4())
self._ioloop = ioloop
self._report = Report(script_path, command_line)
self._uploaded_file_mgr = uploaded_file_manager
self._state = ReportSessionState.REPORT_NOT_RUNNING
# Need to remember the client state here because when a script reruns
# due to the source code changing we need to pass in the previous client state.
self._client_state = ClientState()
self._local_sources_watcher = LocalSourcesWatcher(
self._report, self._on_source_file_changed)
self._sent_initialize_message = False
self._storage = None
self._maybe_reuse_previous_run = False
self._run_on_save = config.get_option("server.runOnSave")
# The ScriptRequestQueue is the means by which we communicate
# with the active ScriptRunner.
self._script_request_queue = ScriptRequestQueue()
self._scriptrunner = None
LOGGER.debug("ReportSession initialized (id=%s)", self.id)
def flush_browser_queue(self):
"""Clear the report queue and return the messages it contained.
The Server calls this periodically to deliver new messages
to the browser connected to this report.
Returns
-------
list[ForwardMsg]
The messages that were removed from the queue and should
be delivered to the browser.
"""
return self._report.flush_browser_queue()
def shutdown(self):
"""Shut down the ReportSession.
It's an error to use a ReportSession after it's been shut down.
"""
if self._state != ReportSessionState.SHUTDOWN_REQUESTED:
LOGGER.debug("Shutting down (id=%s)", self.id)
# Clear any unused session files in upload file manager and media
# file manager
self._uploaded_file_mgr.remove_session_files(self.id)
media_file_manager.clear_session_files(self.id)
media_file_manager.del_expired_files()
# Shut down the ScriptRunner, if one is active.
# self._state must not be set to SHUTDOWN_REQUESTED until
# after this is called.
if self._scriptrunner is not None:
self._enqueue_script_request(ScriptRequest.SHUTDOWN)
self._state = ReportSessionState.SHUTDOWN_REQUESTED
self._local_sources_watcher.close()
def enqueue(self, msg):
"""Enqueue a new ForwardMsg to our browser queue.
This can be called on both the main thread and a ScriptRunner
run thread.
Parameters
----------
msg : ForwardMsg
The message to enqueue
"""
if not config.get_option("client.displayEnabled"):
return
# Avoid having two maybe_handle_execution_control_request running on
# top of each other when tracer is installed. This leads to a lock
# contention.
if not config.get_option("runner.installTracer"):
# If we have an active ScriptRunner, signal that it can handle an
# execution control request. (Copy the scriptrunner reference to
# avoid it being unset from underneath us, as this function can be
# called outside the main thread.)
scriptrunner = self._scriptrunner
if scriptrunner is not None:
scriptrunner.maybe_handle_execution_control_request()
self._report.enqueue(msg)
def enqueue_exception(self, e):
"""Enqueue an Exception message.
Parameters
----------
e : BaseException
"""
# This does a few things:
# 1) Clears the current report in the browser.
# 2) Marks the current report as "stopped" in the browser.
# 3) HACK: Resets any script params that may have been broken (e.g. the
# command-line when rerunning with wrong argv[0])
self._on_scriptrunner_event(
ScriptRunnerEvent.SCRIPT_STOPPED_WITH_SUCCESS)
self._on_scriptrunner_event(ScriptRunnerEvent.SCRIPT_STARTED)
self._on_scriptrunner_event(
ScriptRunnerEvent.SCRIPT_STOPPED_WITH_SUCCESS)
msg = ForwardMsg()
msg.metadata.delta_id = 0
exception_proto.marshall(msg.delta.new_element.exception, e)
self.enqueue(msg)
def request_rerun(self, client_state=None):
"""Signal that we're interested in running the script.
If the script is not already running, it will be started immediately.
Otherwise, a rerun will be requested.
Parameters
----------
client_state : streamlit.proto.ClientState_pb2.ClientState | None
The ClientState protobuf to run the script with, or None
to use previous client state.
"""
if client_state:
rerun_data = RerunData(client_state.query_string,
client_state.widget_states)
else:
rerun_data = RerunData()
self._enqueue_script_request(ScriptRequest.RERUN, rerun_data)
self._set_page_config_allowed = True
def _on_source_file_changed(self):
"""One of our source files changed. Schedule a rerun if appropriate."""
if self._run_on_save:
self.request_rerun()
else:
self._enqueue_file_change_message()
def _clear_queue(self):
self._report.clear()
def _on_scriptrunner_event(self, event, exception=None, client_state=None):
"""Called when our ScriptRunner emits an event.
This is *not* called on the main thread.
Parameters
----------
event : ScriptRunnerEvent
exception : BaseException | None
An exception thrown during compilation. Set only for the
SCRIPT_STOPPED_WITH_COMPILE_ERROR event.
client_state : streamlit.proto.ClientState_pb2.ClientState | None
The ScriptRunner's final ClientState. Set only for the
SHUTDOWN event.
"""
LOGGER.debug("OnScriptRunnerEvent: %s", event)
prev_state = self._state
if event == ScriptRunnerEvent.SCRIPT_STARTED:
if self._state != ReportSessionState.SHUTDOWN_REQUESTED:
self._state = ReportSessionState.REPORT_IS_RUNNING
if config.get_option("server.liveSave"):
# Enqueue into the IOLoop so it runs without blocking AND runs
# on the main thread.
self._ioloop.spawn_callback(self._save_running_report)
self._clear_queue()
self._maybe_enqueue_initialize_message()
self._enqueue_new_report_message()
elif (event == ScriptRunnerEvent.SCRIPT_STOPPED_WITH_SUCCESS
or event == ScriptRunnerEvent.SCRIPT_STOPPED_WITH_COMPILE_ERROR):
if self._state != ReportSessionState.SHUTDOWN_REQUESTED:
self._state = ReportSessionState.REPORT_NOT_RUNNING
script_succeeded = event == ScriptRunnerEvent.SCRIPT_STOPPED_WITH_SUCCESS
self._enqueue_report_finished_message(
ForwardMsg.FINISHED_SUCCESSFULLY if script_succeeded else
ForwardMsg.FINISHED_WITH_COMPILE_ERROR)
if config.get_option("server.liveSave"):
# Enqueue into the IOLoop so it runs without blocking AND runs
# on the main thread.
self._ioloop.spawn_callback(self._save_final_report_and_quit)
if script_succeeded:
# When a script completes successfully, we update our
# LocalSourcesWatcher to account for any source code changes
# that change which modules should be watched. (This is run on
# the main thread, because LocalSourcesWatcher is not
# thread safe.)
self._ioloop.spawn_callback(
self._local_sources_watcher.update_watched_modules)
else:
# When a script fails to compile, we send along the exception.
from streamlit.elements import exception_proto
msg = ForwardMsg()
exception_proto.marshall(
msg.session_event.script_compilation_exception, exception)
self.enqueue(msg)
elif event == ScriptRunnerEvent.SHUTDOWN:
# When ScriptRunner shuts down, update our local reference to it,
# and check to see if we need to spawn a new one. (This is run on
# the main thread.)
if self._state == ReportSessionState.SHUTDOWN_REQUESTED:
# Only clear media files if the script is done running AND the
# report session is actually shutting down.
media_file_manager.clear_session_files(self.id)
def on_shutdown():
self._client_state = client_state
self._scriptrunner = None
# Because a new ScriptEvent could have been enqueued while the
# scriptrunner was shutting down, we check to see if we should
# create a new one. (Otherwise, a newly-enqueued ScriptEvent
# won't be processed until another event is enqueued.)
self._maybe_create_scriptrunner()
self._ioloop.spawn_callback(on_shutdown)
# Send a message if our run state changed
report_was_running = prev_state == ReportSessionState.REPORT_IS_RUNNING
report_is_running = self._state == ReportSessionState.REPORT_IS_RUNNING
if report_is_running != report_was_running:
self._enqueue_session_state_changed_message()
def _enqueue_session_state_changed_message(self):
msg = ForwardMsg()
msg.session_state_changed.run_on_save = self._run_on_save
msg.session_state_changed.report_is_running = (
self._state == ReportSessionState.REPORT_IS_RUNNING)
self.enqueue(msg)
def _enqueue_file_change_message(self):
LOGGER.debug("Enqueuing report_changed message (id=%s)", self.id)
msg = ForwardMsg()
msg.session_event.report_changed_on_disk = True
self.enqueue(msg)
def _maybe_enqueue_initialize_message(self):
if self._sent_initialize_message:
return
self._sent_initialize_message = True
msg = ForwardMsg()
imsg = msg.initialize
imsg.config.sharing_enabled = config.get_option(
"global.sharingMode") != "off"
imsg.config.gather_usage_stats = config.get_option(
"browser.gatherUsageStats")
imsg.config.max_cached_message_age = config.get_option(
"global.maxCachedMessageAge")
imsg.config.mapbox_token = config.get_option("mapbox.token")
LOGGER.debug(
"New browser connection: "
"gather_usage_stats=%s, "
"sharing_enabled=%s, "
"max_cached_message_age=%s",
imsg.config.gather_usage_stats,
imsg.config.sharing_enabled,
imsg.config.max_cached_message_age,
)
imsg.environment_info.streamlit_version = __version__
imsg.environment_info.python_version = ".".join(
map(str, sys.version_info))
imsg.session_state.run_on_save = self._run_on_save
imsg.session_state.report_is_running = (
self._state == ReportSessionState.REPORT_IS_RUNNING)
imsg.user_info.installation_id = Installation.instance(
).installation_id
imsg.user_info.installation_id_v1 = Installation.instance(
).installation_id_v1
imsg.user_info.installation_id_v2 = Installation.instance(
).installation_id_v2
if Credentials.get_current().activation:
imsg.user_info.email = Credentials.get_current().activation.email
else:
imsg.user_info.email = ""
imsg.command_line = self._report.command_line
imsg.session_id = self.id
self.enqueue(msg)
def _enqueue_new_report_message(self):
self._report.generate_new_id()
msg = ForwardMsg()
msg.new_report.id = self._report.report_id
msg.new_report.name = self._report.name
msg.new_report.script_path = self._report.script_path
self.enqueue(msg)
def _enqueue_report_finished_message(self, status):
"""Enqueue a report_finished ForwardMsg.
Parameters
----------
status : ReportFinishedStatus
"""
msg = ForwardMsg()
msg.report_finished = status
self.enqueue(msg)
def handle_rerun_script_request(self, client_state=None, is_preheat=False):
"""Tell the ScriptRunner to re-run its report.
Parameters
----------
client_state : streamlit.proto.ClientState_pb2.ClientState | None
The ClientState protobuf to run the script with, or None
to use previous client state.
is_preheat: boolean
True if this ReportSession should run the script immediately, and
then ignore the next rerun request if it matches the already-ran
widget state.
"""
if is_preheat:
self._maybe_reuse_previous_run = True # For next time.
elif self._maybe_reuse_previous_run:
# If this is a "preheated" ReportSession, reuse the previous run if
# the widget state matches. But only do this one time ever.
self._maybe_reuse_previous_run = False
has_client_state = False
if client_state is not None:
has_query_string = client_state.query_string != ""
has_widget_states = (
client_state.widget_states is not None
and len(client_state.widget_states.widgets) > 0)
has_client_state = has_query_string or has_widget_states
if not has_client_state:
LOGGER.debug(
"Skipping rerun since the preheated run is the same")
return
self.request_rerun(client_state)
def handle_stop_script_request(self):
"""Tell the ScriptRunner to stop running its report."""
self._enqueue_script_request(ScriptRequest.STOP)
def handle_clear_cache_request(self):
"""Clear this report's cache.
Because this cache is global, it will be cleared for all users.
"""
# Setting verbose=True causes clear_cache to print to stdout.
# Since this command was initiated from the browser, the user
# doesn't need to see the results of the command in their
# terminal.
caching.clear_cache()
def handle_set_run_on_save_request(self, new_value):
"""Change our run_on_save flag to the given value.
The browser will be notified of the change.
Parameters
----------
new_value : bool
New run_on_save value
"""
self._run_on_save = new_value
self._enqueue_session_state_changed_message()
def _enqueue_script_request(self, request, data=None):
"""Enqueue a ScriptEvent into our ScriptEventQueue.
If a script thread is not already running, one will be created
to handle the event.
Parameters
----------
request : ScriptRequest
The type of request.
data : Any
Data associated with the request, if any.
"""
if self._state == ReportSessionState.SHUTDOWN_REQUESTED:
LOGGER.warning("Discarding %s request after shutdown" % request)
return
self._script_request_queue.enqueue(request, data)
self._maybe_create_scriptrunner()
def _maybe_create_scriptrunner(self):
"""Create a new ScriptRunner if we have unprocessed script requests.
This is called every time a ScriptRequest is enqueued, and also
after a ScriptRunner shuts down, in case new requests were enqueued
during its termination.
This function should only be called on the main thread.
"""
if (self._state == ReportSessionState.SHUTDOWN_REQUESTED
or self._scriptrunner is not None
or not self._script_request_queue.has_request):
return
# Create the ScriptRunner, attach event handlers, and start it
self._scriptrunner = ScriptRunner(
session_id=self.id,
report=self._report,
enqueue_forward_msg=self.enqueue,
client_state=self._client_state,
request_queue=self._script_request_queue,
uploaded_file_mgr=self._uploaded_file_mgr,
)
self._scriptrunner.on_event.connect(self._on_scriptrunner_event)
self._scriptrunner.start()
@tornado.gen.coroutine
def handle_save_request(self, ws):
"""Save serialized version of report deltas to the cloud.
"Progress" ForwardMsgs will be sent to the client during the upload.
These messages are sent "out of band" - that is, they don't get
enqueued into the ReportQueue (because they're not part of the report).
Instead, they're written directly to the report's WebSocket.
Parameters
----------
ws : _BrowserWebSocketHandler
The report's websocket handler.
"""
@tornado.gen.coroutine
def progress(percent):
progress_msg = ForwardMsg()
progress_msg.upload_report_progress = percent
yield ws.write_message(serialize_forward_msg(progress_msg),
binary=True)
# Indicate that the save is starting.
try:
yield progress(0)
url = yield self._save_final_report(progress)
# Indicate that the save is done.
progress_msg = ForwardMsg()
progress_msg.report_uploaded = url
yield ws.write_message(serialize_forward_msg(progress_msg),
binary=True)
except Exception as e:
# Horrible hack to show something if something breaks.
err_msg = "%s: %s" % (type(e).__name__, str(e)
or "No further details.")
progress_msg = ForwardMsg()
progress_msg.report_uploaded = err_msg
yield ws.write_message(serialize_forward_msg(progress_msg),
binary=True)
LOGGER.warning("Failed to save report:", exc_info=e)
@tornado.gen.coroutine
def _save_running_report(self):
files = self._report.serialize_running_report_to_files()
url = yield self._get_storage().save_report_files(
self._report.report_id, files)
if config.get_option("server.liveSave"):
url_util.print_url("Saved running app", url)
raise tornado.gen.Return(url)
@tornado.gen.coroutine
def _save_final_report(self, progress_coroutine=None):
files = self._report.serialize_final_report_to_files()
url = yield self._get_storage().save_report_files(
self._report.report_id, files, progress_coroutine)
if config.get_option("server.liveSave"):
url_util.print_url("Saved final app", url)
raise tornado.gen.Return(url)
@tornado.gen.coroutine
def _save_final_report_and_quit(self):
yield self._save_final_report()
self._ioloop.stop()
def _get_storage(self):
if self._storage is None:
sharing_mode = config.get_option("global.sharingMode")
if sharing_mode == "s3":
self._storage = S3Storage()
elif sharing_mode == "file":
self._storage = FileStorage()
else:
raise RuntimeError("Unsupported sharing mode '%s'" %
sharing_mode)
return self._storage
def test_rerun_data_coalescing(self):
"""Test that multiple RERUN requests get coalesced with
expected values.
(This is similar to widgets_test.test_coalesce_widget_states -
it's testing the same thing, but through the ScriptEventQueue
interface.)
"""
queue = ScriptRequestQueue()
session_state = SessionState()
states = WidgetStates()
_create_widget("trigger", states).trigger_value = True
_create_widget("int", states).int_value = 123
queue.enqueue(ScriptRequest.RERUN, RerunData(widget_states=states))
states = WidgetStates()
_create_widget("trigger", states).trigger_value = False
_create_widget("int", states).int_value = 456
session_state.set_metadata(
WidgetMetadata("trigger", lambda x, s: x, None, "trigger_value"))
session_state.set_metadata(
WidgetMetadata("int", lambda x, s: x, lambda x: x, "int_value"))
queue.enqueue(ScriptRequest.RERUN, RerunData(widget_states=states))
event, data = queue.dequeue()
self.assertEqual(event, ScriptRequest.RERUN)
session_state.set_widgets_from_proto(data.widget_states)
# Coalesced triggers should be True if either the old or
# new value was True
self.assertEqual(True, session_state.get("trigger"))
# Other widgets should have their newest value
self.assertEqual(456, session_state.get("int"))
# We should have no more events
self.assertEqual((None, None), queue.dequeue(),
"Expected empty event queue")
# Test that we can coalesce if previous widget state is None
queue.enqueue(ScriptRequest.RERUN, RerunData(widget_states=None))
queue.enqueue(ScriptRequest.RERUN, RerunData(widget_states=None))
states = WidgetStates()
_create_widget("int", states).int_value = 789
queue.enqueue(ScriptRequest.RERUN, RerunData(widget_states=states))
event, data = queue.dequeue()
session_state.set_widgets_from_proto(data.widget_states)
self.assertEqual(event, ScriptRequest.RERUN)
self.assertEqual(789, session_state.get("int"))
# We should have no more events
self.assertEqual((None, None), queue.dequeue(),
"Expected empty event queue")
# Test that we can coalesce if our *new* widget state is None
states = WidgetStates()
_create_widget("int", states).int_value = 101112
queue.enqueue(ScriptRequest.RERUN, RerunData(widget_states=states))
queue.enqueue(ScriptRequest.RERUN, RerunData(widget_states=None))
event, data = queue.dequeue()
session_state.set_widgets_from_proto(data.widget_states)
self.assertEqual(event, ScriptRequest.RERUN)
self.assertEqual(101112, session_state.get("int"))
# We should have no more events
self.assertEqual((None, None), queue.dequeue(),
"Expected empty event queue")
def __init__(
self,
ioloop: tornado.ioloop.IOLoop,
session_data: SessionData,
uploaded_file_manager: UploadedFileManager,
message_enqueued_callback: Optional[Callable[[], None]],
local_sources_watcher: LocalSourcesWatcher,
):
"""Initialize the AppSession.
Parameters
----------
ioloop : tornado.ioloop.IOLoop
The Tornado IOLoop that we're running within.
session_data : SessionData
Object storing parameters related to running a script
uploaded_file_manager : UploadedFileManager
The server's UploadedFileManager.
message_enqueued_callback : Callable[[], None]
After enqueuing a message, this callable notification will be invoked.
local_sources_watcher: LocalSourcesWatcher
The file watcher that lets the session know local files have changed.
"""
# Each AppSession has a unique string ID.
self.id = str(uuid.uuid4())
self._ioloop = ioloop
self._session_data = session_data
self._uploaded_file_mgr = uploaded_file_manager
self._message_enqueued_callback = message_enqueued_callback
self._state = AppSessionState.APP_NOT_RUNNING
# Need to remember the client state here because when a script reruns
# due to the source code changing we need to pass in the previous client state.
self._client_state = ClientState()
self._local_sources_watcher = local_sources_watcher
self._local_sources_watcher.register_file_change_callback(
self._on_source_file_changed)
self._stop_config_listener = config.on_config_parsed(
self._on_source_file_changed, force_connect=True)
# The script should rerun when the `secrets.toml` file has been changed.
secrets._file_change_listener.connect(self._on_secrets_file_changed)
self._run_on_save = config.get_option("server.runOnSave")
# The ScriptRequestQueue is the means by which we communicate
# with the active ScriptRunner.
self._script_request_queue = ScriptRequestQueue()
self._scriptrunner: Optional[ScriptRunner] = None
# This needs to be lazily imported to avoid a dependency cycle.
from streamlit.state.session_state import SessionState
self._session_state = SessionState()
LOGGER.debug("AppSession initialized (id=%s)", self.id)
class AppSession:
"""
Contains session data for a single "user" of an active app
(that is, a connected browser tab).
Each AppSession has its own SessionData, root DeltaGenerator, ScriptRunner,
and widget state.
An AppSession is attached to each thread involved in running its script.
"""
def __init__(
self,
ioloop: tornado.ioloop.IOLoop,
session_data: SessionData,
uploaded_file_manager: UploadedFileManager,
message_enqueued_callback: Optional[Callable[[], None]],
local_sources_watcher: LocalSourcesWatcher,
):
"""Initialize the AppSession.
Parameters
----------
ioloop : tornado.ioloop.IOLoop
The Tornado IOLoop that we're running within.
session_data : SessionData
Object storing parameters related to running a script
uploaded_file_manager : UploadedFileManager
The server's UploadedFileManager.
message_enqueued_callback : Callable[[], None]
After enqueuing a message, this callable notification will be invoked.
local_sources_watcher: LocalSourcesWatcher
The file watcher that lets the session know local files have changed.
"""
# Each AppSession has a unique string ID.
self.id = str(uuid.uuid4())
self._ioloop = ioloop
self._session_data = session_data
self._uploaded_file_mgr = uploaded_file_manager
self._message_enqueued_callback = message_enqueued_callback
self._state = AppSessionState.APP_NOT_RUNNING
# Need to remember the client state here because when a script reruns
# due to the source code changing we need to pass in the previous client state.
self._client_state = ClientState()
self._local_sources_watcher = local_sources_watcher
self._local_sources_watcher.register_file_change_callback(
self._on_source_file_changed)
self._stop_config_listener = config.on_config_parsed(
self._on_source_file_changed, force_connect=True)
# The script should rerun when the `secrets.toml` file has been changed.
secrets._file_change_listener.connect(self._on_secrets_file_changed)
self._run_on_save = config.get_option("server.runOnSave")
# The ScriptRequestQueue is the means by which we communicate
# with the active ScriptRunner.
self._script_request_queue = ScriptRequestQueue()
self._scriptrunner: Optional[ScriptRunner] = None
# This needs to be lazily imported to avoid a dependency cycle.
from streamlit.state.session_state import SessionState
self._session_state = SessionState()
LOGGER.debug("AppSession initialized (id=%s)", self.id)
def flush_browser_queue(self) -> List[ForwardMsg]:
"""Clear the forward message queue and return the messages it contained.
The Server calls this periodically to deliver new messages
to the browser connected to this app.
Returns
-------
list[ForwardMsg]
The messages that were removed from the queue and should
be delivered to the browser.
"""
return self._session_data.flush_browser_queue()
def shutdown(self) -> None:
"""Shut down the AppSession.
It's an error to use a AppSession after it's been shut down.
"""
if self._state != AppSessionState.SHUTDOWN_REQUESTED:
LOGGER.debug("Shutting down (id=%s)", self.id)
# Clear any unused session files in upload file manager and media
# file manager
self._uploaded_file_mgr.remove_session_files(self.id)
in_memory_file_manager.clear_session_files(self.id)
in_memory_file_manager.del_expired_files()
# Shut down the ScriptRunner, if one is active.
# self._state must not be set to SHUTDOWN_REQUESTED until
# after this is called.
if self._scriptrunner is not None:
self._enqueue_script_request(ScriptRequest.SHUTDOWN)
self._state = AppSessionState.SHUTDOWN_REQUESTED
self._local_sources_watcher.close()
if self._stop_config_listener is not None:
self._stop_config_listener()
secrets._file_change_listener.disconnect(
self._on_secrets_file_changed)
def enqueue(self, msg: ForwardMsg) -> None:
"""Enqueue a new ForwardMsg to our browser queue.
This can be called on both the main thread and a ScriptRunner
run thread.
Parameters
----------
msg : ForwardMsg
The message to enqueue
"""
if not config.get_option("client.displayEnabled"):
return
# Avoid having two maybe_handle_execution_control_request running on
# top of each other when tracer is installed. This leads to a lock
# contention.
if not config.get_option("runner.installTracer"):
# If we have an active ScriptRunner, signal that it can handle an
# execution control request. (Copy the scriptrunner reference to
# avoid it being unset from underneath us, as this function can be
# called outside the main thread.)
scriptrunner = self._scriptrunner
if scriptrunner is not None:
scriptrunner.maybe_handle_execution_control_request()
self._session_data.enqueue(msg)
if self._message_enqueued_callback:
self._message_enqueued_callback()
def enqueue_exception(self, e: BaseException) -> None:
"""Enqueue an Exception message."""
# This does a few things:
# 1) Clears the current app in the browser.
# 2) Marks the current app as "stopped" in the browser.
# 3) HACK: Resets any script params that may have been broken (e.g. the
# command-line when rerunning with wrong argv[0])
self._on_scriptrunner_event(
ScriptRunnerEvent.SCRIPT_STOPPED_WITH_SUCCESS)
self._on_scriptrunner_event(ScriptRunnerEvent.SCRIPT_STARTED)
self._on_scriptrunner_event(
ScriptRunnerEvent.SCRIPT_STOPPED_WITH_SUCCESS)
msg = ForwardMsg()
exception_utils.marshall(msg.delta.new_element.exception, e)
self.enqueue(msg)
def request_rerun(self, client_state: Optional[ClientState]) -> None:
"""Signal that we're interested in running the script.
If the script is not already running, it will be started immediately.
Otherwise, a rerun will be requested.
Parameters
----------
client_state : streamlit.proto.ClientState_pb2.ClientState | None
The ClientState protobuf to run the script with, or None
to use previous client state.
"""
if client_state:
rerun_data = RerunData(client_state.query_string,
client_state.widget_states)
else:
rerun_data = RerunData()
self._enqueue_script_request(ScriptRequest.RERUN, rerun_data)
@property
def session_state(self) -> "SessionState":
return self._session_state
def _on_source_file_changed(self) -> None:
"""One of our source files changed. Schedule a rerun if appropriate."""
if self._run_on_save:
self.request_rerun(self._client_state)
else:
self._enqueue_file_change_message()
def _on_secrets_file_changed(self, _) -> None:
"""Called when `secrets._file_change_listener` emits a Signal."""
# NOTE: At the time of writing, this function only calls `_on_source_file_changed`.
# The reason behind creating this function instead of just passing `_on_source_file_changed`
# to `connect` / `disconnect` directly is that every function that is passed to `connect` / `disconnect`
# must have at least one argument for `sender` (in this case we don't really care about it, thus `_`),
# and introducing an unnecessary argument to `_on_source_file_changed` just for this purpose sounded finicky.
self._on_source_file_changed()
def _clear_queue(self) -> None:
self._session_data.clear()
def _on_scriptrunner_event(
self,
event: ScriptRunnerEvent,
exception: Optional[BaseException] = None,
client_state: Optional[ClientState] = None,
) -> None:
"""Called when our ScriptRunner emits an event.
This is *not* called on the main thread.
Parameters
----------
event : ScriptRunnerEvent
exception : BaseException | None
An exception thrown during compilation. Set only for the
SCRIPT_STOPPED_WITH_COMPILE_ERROR event.
client_state : streamlit.proto.ClientState_pb2.ClientState | None
The ScriptRunner's final ClientState. Set only for the
SHUTDOWN event.
"""
LOGGER.debug("OnScriptRunnerEvent: %s", event)
prev_state = self._state
if event == ScriptRunnerEvent.SCRIPT_STARTED:
if self._state != AppSessionState.SHUTDOWN_REQUESTED:
self._state = AppSessionState.APP_IS_RUNNING
self._clear_queue()
self._enqueue_new_session_message()
elif (event == ScriptRunnerEvent.SCRIPT_STOPPED_WITH_SUCCESS
or event == ScriptRunnerEvent.SCRIPT_STOPPED_WITH_COMPILE_ERROR):
if self._state != AppSessionState.SHUTDOWN_REQUESTED:
self._state = AppSessionState.APP_NOT_RUNNING
script_succeeded = event == ScriptRunnerEvent.SCRIPT_STOPPED_WITH_SUCCESS
self._enqueue_script_finished_message(
ForwardMsg.FINISHED_SUCCESSFULLY if script_succeeded else
ForwardMsg.FINISHED_WITH_COMPILE_ERROR)
if script_succeeded:
# When a script completes successfully, we update our
# LocalSourcesWatcher to account for any source code changes
# that change which modules should be watched. (This is run on
# the main thread, because LocalSourcesWatcher is not
# thread safe.)
self._ioloop.spawn_callback(
self._local_sources_watcher.update_watched_modules)
else:
msg = ForwardMsg()
exception_utils.marshall(
msg.session_event.script_compilation_exception, exception)
self.enqueue(msg)
elif event == ScriptRunnerEvent.SHUTDOWN:
# When ScriptRunner shuts down, update our local reference to it,
# and check to see if we need to spawn a new one. (This is run on
# the main thread.)
assert (
client_state
is not None), "client_state must be set for the SHUTDOWN event"
if self._state == AppSessionState.SHUTDOWN_REQUESTED:
# Only clear media files if the script is done running AND the
# session is actually shutting down.
in_memory_file_manager.clear_session_files(self.id)
def on_shutdown():
# We assert above that this is non-null
self._client_state = cast(ClientState, client_state)
self._scriptrunner = None
# Because a new ScriptEvent could have been enqueued while the
# scriptrunner was shutting down, we check to see if we should
# create a new one. (Otherwise, a newly-enqueued ScriptEvent
# won't be processed until another event is enqueued.)
self._maybe_create_scriptrunner()
self._ioloop.spawn_callback(on_shutdown)
# Send a message if our run state changed
app_was_running = prev_state == AppSessionState.APP_IS_RUNNING
app_is_running = self._state == AppSessionState.APP_IS_RUNNING
if app_is_running != app_was_running:
self._enqueue_session_state_changed_message()
def _enqueue_session_state_changed_message(self) -> None:
msg = ForwardMsg()
msg.session_state_changed.run_on_save = self._run_on_save
msg.session_state_changed.script_is_running = (
self._state == AppSessionState.APP_IS_RUNNING)
self.enqueue(msg)
def _enqueue_file_change_message(self) -> None:
LOGGER.debug("Enqueuing script_changed message (id=%s)", self.id)
msg = ForwardMsg()
msg.session_event.script_changed_on_disk = True
self.enqueue(msg)
def _enqueue_new_session_message(self) -> None:
msg = ForwardMsg()
msg.new_session.script_run_id = _generate_scriptrun_id()
msg.new_session.name = self._session_data.name
msg.new_session.script_path = self._session_data.script_path
_populate_config_msg(msg.new_session.config)
_populate_theme_msg(msg.new_session.custom_theme)
# Immutable session data. We send this every time a new session is
# started, to avoid having to track whether the client has already
# received it. It does not change from run to run; it's up to the
# to perform one-time initialization only once.
imsg = msg.new_session.initialize
_populate_user_info_msg(imsg.user_info)
imsg.environment_info.streamlit_version = __version__
imsg.environment_info.python_version = ".".join(
map(str, sys.version_info))
imsg.session_state.run_on_save = self._run_on_save
imsg.session_state.script_is_running = (
self._state == AppSessionState.APP_IS_RUNNING)
imsg.command_line = self._session_data.command_line
imsg.session_id = self.id
self.enqueue(msg)
def _enqueue_script_finished_message(
self, status: "ForwardMsg.ScriptFinishedStatus.ValueType") -> None:
"""Enqueue a script_finished ForwardMsg."""
msg = ForwardMsg()
msg.script_finished = status
self.enqueue(msg)
def handle_git_information_request(self) -> None:
msg = ForwardMsg()
try:
from streamlit.git_util import GitRepo
repo = GitRepo(self._session_data.script_path)
repo_info = repo.get_repo_info()
if repo_info is None:
return
repository_name, branch, module = repo_info
msg.git_info_changed.repository = repository_name
msg.git_info_changed.branch = branch
msg.git_info_changed.module = module
msg.git_info_changed.untracked_files[:] = repo.untracked_files
msg.git_info_changed.uncommitted_files[:] = repo.uncommitted_files
if repo.is_head_detached:
msg.git_info_changed.state = GitInfo.GitStates.HEAD_DETACHED
elif len(repo.ahead_commits) > 0:
msg.git_info_changed.state = GitInfo.GitStates.AHEAD_OF_REMOTE
else:
msg.git_info_changed.state = GitInfo.GitStates.DEFAULT
self.enqueue(msg)
except Exception as e:
# Users may never even install Git in the first place, so this
# error requires no action. It can be useful for debugging.
LOGGER.debug("Obtaining Git information produced an error",
exc_info=e)
def handle_rerun_script_request(self,
client_state: Optional[ClientState] = None
) -> None:
"""Tell the ScriptRunner to re-run its script.
Parameters
----------
client_state : streamlit.proto.ClientState_pb2.ClientState | None
The ClientState protobuf to run the script with, or None
to use previous client state.
"""
self.request_rerun(client_state)
def handle_stop_script_request(self) -> None:
"""Tell the ScriptRunner to stop running its script."""
self._enqueue_script_request(ScriptRequest.STOP)
def handle_clear_cache_request(self) -> None:
"""Clear this app's cache.
Because this cache is global, it will be cleared for all users.
"""
legacy_caching.clear_cache()
caching.memo.clear()
caching.singleton.clear()
self._session_state.clear_state()
def handle_set_run_on_save_request(self, new_value: bool) -> None:
"""Change our run_on_save flag to the given value.
The browser will be notified of the change.
Parameters
----------
new_value : bool
New run_on_save value
"""
self._run_on_save = new_value
self._enqueue_session_state_changed_message()
def _enqueue_script_request(self,
request: ScriptRequest,
data: Any = None) -> None:
"""Enqueue a ScriptEvent into our ScriptEventQueue.
If a script thread is not already running, one will be created
to handle the event.
Parameters
----------
request : ScriptRequest
The type of request.
data : Any
Data associated with the request, if any.
"""
if self._state == AppSessionState.SHUTDOWN_REQUESTED:
LOGGER.warning("Discarding %s request after shutdown" % request)
return
self._script_request_queue.enqueue(request, data)
self._maybe_create_scriptrunner()
def _maybe_create_scriptrunner(self) -> None:
"""Create a new ScriptRunner if we have unprocessed script requests.
This is called every time a ScriptRequest is enqueued, and also
after a ScriptRunner shuts down, in case new requests were enqueued
during its termination.
This function should only be called on the main thread.
"""
if (self._state == AppSessionState.SHUTDOWN_REQUESTED
or self._scriptrunner is not None
or not self._script_request_queue.has_request):
return
# Create the ScriptRunner, attach event handlers, and start it
self._scriptrunner = ScriptRunner(
session_id=self.id,
session_data=self._session_data,
enqueue_forward_msg=self.enqueue,
client_state=self._client_state,
request_queue=self._script_request_queue,
session_state=self._session_state,
uploaded_file_mgr=self._uploaded_file_mgr,
)
self._scriptrunner.on_event.connect(self._on_scriptrunner_event)
self._scriptrunner.start()
class TestScriptRunner(ScriptRunner):
"""Subclasses ScriptRunner to provide some testing features."""
def __init__(self, script_name):
"""Initializes the ScriptRunner for the given script_name"""
# DeltaGenerator deltas will be enqueued into self.forward_msg_queue.
self.forward_msg_queue = ForwardMsgQueue()
self.script_request_queue = ScriptRequestQueue()
main_script_path = os.path.join(os.path.dirname(__file__), "test_data",
script_name)
super(TestScriptRunner, self).__init__(
session_id="test session id",
session_data=SessionData(main_script_path, "test command line"),
enqueue_forward_msg=self.forward_msg_queue.enqueue,
client_state=ClientState(),
session_state=SessionState(),
request_queue=self.script_request_queue,
uploaded_file_mgr=UploadedFileManager(),
)
# Accumulates uncaught exceptions thrown by our run thread.
self.script_thread_exceptions = []
# Accumulates all ScriptRunnerEvents emitted by us.
self.events: List[ScriptRunnerEvent] = []
self.event_data: List[Any] = []
def record_event(sender: Optional[ScriptRunner],
event: ScriptRunnerEvent, **kwargs):
# Assert that we're not getting unexpected `sender` params
# from ScriptRunner.on_event
assert (sender is None
or sender == self), "Unexpected ScriptRunnerEvent sender!"
self.events.append(event)
self.event_data.append(kwargs)
self.on_event.connect(record_event, weak=False)
def enqueue_rerun(self, argv=None, widget_states=None, query_string=""):
self.script_request_queue.enqueue(
ScriptRequest.RERUN,
RerunData(widget_states=widget_states, query_string=query_string),
)
def enqueue_stop(self):
self.script_request_queue.enqueue(ScriptRequest.STOP)
def enqueue_shutdown(self):
self.script_request_queue.enqueue(ScriptRequest.SHUTDOWN)
def _run_script_thread(self):
try:
super()._run_script_thread()
except BaseException as e:
self.script_thread_exceptions.append(e)
def _run_script(self, rerun_data):
self.forward_msg_queue.clear()
super()._run_script(rerun_data)
def join(self):
"""Joins the run thread, if it was started"""
if self._script_thread is not None:
self._script_thread.join()
def clear_deltas(self):
"""Clear all delta messages from our ForwardMsgQueue"""
self.forward_msg_queue.clear()
def deltas(self) -> List[Delta]:
"""Return the delta messages in our ForwardMsgQueue"""
return [
msg.delta for msg in self.forward_msg_queue._queue
if msg.HasField("delta")
]
def elements(self) -> List[Element]:
"""Return the delta.new_element messages in our ForwardMsgQueue."""
return [delta.new_element for delta in self.deltas()]
def text_deltas(self) -> List[str]:
"""Return the string contents of text deltas in our ForwardMsgQueue"""
return [
element.text.body for element in self.elements()
if element.WhichOneof("type") == "text"
]
def get_widget_id(self, widget_type, label):
"""Returns the id of the widget with the specified type and label"""
for delta in self.deltas():
new_element = getattr(delta, "new_element", None)
widget = getattr(new_element, widget_type, None)
widget_label = getattr(widget, "label", None)
if widget_label == label:
return widget.id
return None