2022-05-23 00:16:32 +04:00

359 lines
12 KiB
Python

# Copyright 2018-2022 Streamlit Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
import os
import signal
import sys
from typing import Any, Dict, List, Optional
import click
import tornado.ioloop
from streamlit import session_data
from streamlit.git_util import GitRepo, MIN_GIT_VERSION
from streamlit import version
from streamlit import config
from streamlit import net_util
from streamlit import url_util
from streamlit import env_util
from streamlit import secrets
from streamlit import util
from streamlit.config import CONFIG_FILENAMES
from streamlit.logger import get_logger
from streamlit.secrets import SECRETS_FILE_LOC
from streamlit.server.server import Server, server_address_is_unix_socket
from streamlit.watcher import report_watchdog_availability, watch_file
LOGGER = get_logger(__name__)
# Wait for 1 second before opening a browser. This gives old tabs a chance to
# reconnect.
# This must be >= 2 * WebSocketConnection.ts#RECONNECT_WAIT_TIME_MS.
BROWSER_WAIT_TIMEOUT_SEC = 1
NEW_VERSION_TEXT = """
%(new_version)s
See what's new at https://discuss.streamlit.io/c/announcements
Enter the following command to upgrade:
%(prompt)s %(command)s
""" % {
"new_version": click.style(
"A new version of Streamlit is available.", fg="blue", bold=True
),
"prompt": click.style("$", fg="blue"),
"command": click.style("pip install streamlit --upgrade", bold=True),
}
def _set_up_signal_handler() -> None:
LOGGER.debug("Setting up signal handler")
def signal_handler(signal_number, stack_frame):
# The server will shut down its threads and stop the ioloop
Server.get_current().stop(from_signal=True)
signal.signal(signal.SIGTERM, signal_handler)
signal.signal(signal.SIGINT, signal_handler)
if sys.platform == "win32":
signal.signal(signal.SIGBREAK, signal_handler)
else:
signal.signal(signal.SIGQUIT, signal_handler)
def _fix_sys_path(main_script_path: str) -> None:
"""Add the script's folder to the sys path.
Python normally does this automatically, but since we exec the script
ourselves we need to do it instead.
"""
sys.path.insert(0, os.path.dirname(main_script_path))
def _fix_matplotlib_crash() -> None:
"""Set Matplotlib backend to avoid a crash.
The default Matplotlib backend crashes Python on OSX when run on a thread
that's not the main thread, so here we set a safer backend as a fix.
Users can always disable this behavior by setting the config
runner.fixMatplotlib = false.
This fix is OS-independent. We didn't see a good reason to make this
Mac-only. Consistency within Streamlit seemed more important.
"""
if config.get_option("runner.fixMatplotlib"):
try:
# TODO: a better option may be to set
# os.environ["MPLBACKEND"] = "Agg". We'd need to do this towards
# the top of __init__.py, before importing anything that imports
# pandas (which imports matplotlib). Alternately, we could set
# this environment variable in a new entrypoint defined in
# setup.py. Both of these introduce additional trickiness: they
# need to run without consulting streamlit.config.get_option,
# because this would import streamlit, and therefore matplotlib.
import matplotlib
matplotlib.use("Agg")
except ImportError:
pass
def _fix_tornado_crash() -> None:
"""Set default asyncio policy to be compatible with Tornado 6.
Tornado 6 (at least) is not compatible with the default
asyncio implementation on Windows. So here we
pick the older SelectorEventLoopPolicy when the OS is Windows
if the known-incompatible default policy is in use.
This has to happen as early as possible to make it a low priority and
overrideable
See: https://github.com/tornadoweb/tornado/issues/2608
FIXME: if/when tornado supports the defaults in asyncio,
remove and bump tornado requirement for py38
"""
if env_util.IS_WINDOWS and sys.version_info >= (3, 8):
import asyncio
try:
from asyncio import ( # type: ignore[attr-defined]
WindowsProactorEventLoopPolicy,
WindowsSelectorEventLoopPolicy,
)
except ImportError:
pass
# Not affected
else:
if type(asyncio.get_event_loop_policy()) is WindowsProactorEventLoopPolicy:
# WindowsProactorEventLoopPolicy is not compatible with
# Tornado 6 fallback to the pre-3.8 default of Selector
asyncio.set_event_loop_policy(WindowsSelectorEventLoopPolicy())
def _fix_sys_argv(main_script_path: str, args: List[str]) -> None:
"""sys.argv needs to exclude streamlit arguments and parameters
and be set to what a user's script may expect.
"""
import sys
sys.argv = [main_script_path] + list(args)
def _on_server_start(server: Server) -> None:
_maybe_print_old_git_warning(server.main_script_path)
_print_url(server.is_running_hello)
report_watchdog_availability()
_print_new_version_message()
# Load secrets.toml if it exists. If the file doesn't exist, this
# function will return without raising an exception. We catch any parse
# errors and display them here.
try:
secrets.load_if_toml_exists()
except BaseException as e:
LOGGER.error(f"Failed to load {SECRETS_FILE_LOC}", exc_info=e)
def maybe_open_browser():
if config.get_option("server.headless"):
# Don't open browser when in headless mode.
return
if server.browser_is_connected:
# Don't auto-open browser if there's already a browser connected.
# This can happen if there's an old tab repeatedly trying to
# connect, and it happens to success before we launch the browser.
return
if config.is_manually_set("browser.serverAddress"):
addr = config.get_option("browser.serverAddress")
elif config.is_manually_set("server.address"):
if server_address_is_unix_socket():
# Don't open browser when server address is an unix socket
return
addr = config.get_option("server.address")
else:
addr = "localhost"
util.open_browser(session_data.get_url(addr))
# Schedule the browser to open using the IO Loop on the main thread, but
# only if no other browser connects within 1s.
ioloop = tornado.ioloop.IOLoop.current()
ioloop.call_later(BROWSER_WAIT_TIMEOUT_SEC, maybe_open_browser)
def _fix_pydeck_mapbox_api_warning() -> None:
"""Sets MAPBOX_API_KEY environment variable needed for PyDeck otherwise it will throw an exception"""
os.environ["MAPBOX_API_KEY"] = config.get_option("mapbox.token")
def _print_new_version_message() -> None:
if version.should_show_new_version_notice():
click.secho(NEW_VERSION_TEXT)
def _print_url(is_running_hello: bool) -> None:
if is_running_hello:
title_message = "Welcome to Streamlit. Check out our demo in your browser."
else:
title_message = "You can now view your Streamlit app in your browser."
named_urls = []
if config.is_manually_set("browser.serverAddress"):
named_urls = [
("URL", session_data.get_url(config.get_option("browser.serverAddress")))
]
elif (
config.is_manually_set("server.address") and not server_address_is_unix_socket()
):
named_urls = [
("URL", session_data.get_url(config.get_option("server.address"))),
]
elif config.get_option("server.headless"):
internal_ip = net_util.get_internal_ip()
if internal_ip:
named_urls.append(("Network URL", session_data.get_url(internal_ip)))
external_ip = net_util.get_external_ip()
if external_ip:
named_urls.append(("External URL", session_data.get_url(external_ip)))
else:
named_urls = [
("Local URL", session_data.get_url("localhost")),
]
internal_ip = net_util.get_internal_ip()
if internal_ip:
named_urls.append(("Network URL", session_data.get_url(internal_ip)))
click.secho("")
click.secho(" %s" % title_message, fg="blue", bold=True)
click.secho("")
for url_name, url in named_urls:
url_util.print_url(url_name, url)
click.secho("")
if is_running_hello:
click.secho(" Ready to create your own Python apps super quickly?")
click.secho(" Head over to ", nl=False)
click.secho("https://docs.streamlit.io", bold=True)
click.secho("")
click.secho(" May you create awesome apps!")
click.secho("")
click.secho("")
def _maybe_print_old_git_warning(main_script_path: str) -> None:
"""If our script is running in a Git repo, and we're running a very old
Git version, print a warning that Git integration will be unavailable.
"""
repo = GitRepo(main_script_path)
if (
not repo.is_valid()
and repo.git_version is not None
and repo.git_version < MIN_GIT_VERSION
):
git_version_string = ".".join(str(val) for val in repo.git_version)
min_version_string = ".".join(str(val) for val in MIN_GIT_VERSION)
click.secho("")
click.secho(" Git integration is disabled.", fg="yellow", bold=True)
click.secho("")
click.secho(
f" Streamlit requires Git {min_version_string} or later, "
f"but you have {git_version_string}.",
fg="yellow",
)
click.secho(
" Git is used by Streamlit Cloud (https://streamlit.io/cloud).",
fg="yellow",
)
click.secho(" To enable this feature, please update Git.", fg="yellow")
def load_config_options(flag_options: Dict[str, Any]) -> None:
"""Load config options from config.toml files, then overlay the ones set by
flag_options.
The "streamlit run" command supports passing Streamlit's config options
as flags. This function reads through the config options set via flag,
massages them, and passes them to get_config_options() so that they
overwrite config option defaults and those loaded from config.toml files.
Parameters
----------
flag_options : Dict[str, Any]
A dict of config options where the keys are the CLI flag version of the
config option names.
"""
options_from_flags = {
name.replace("_", "."): val
for name, val in flag_options.items()
if val is not None
}
# Force a reparse of config files (if they exist). The result is cached
# for future calls.
config.get_config_options(force_reparse=True, options_from_flags=options_from_flags)
def _install_config_watchers(flag_options: Dict[str, Any]) -> None:
def on_config_changed(_path):
load_config_options(flag_options)
for filename in CONFIG_FILENAMES:
if os.path.exists(filename):
watch_file(filename, on_config_changed)
def run(
main_script_path: str,
command_line: Optional[str],
args: List[str],
flag_options: Dict[str, Any],
) -> None:
"""Run a script in a separate thread and start a server for the app.
This starts a blocking ioloop.
"""
_fix_sys_path(main_script_path)
_fix_matplotlib_crash()
_fix_tornado_crash()
_fix_sys_argv(main_script_path, args)
_fix_pydeck_mapbox_api_warning()
_install_config_watchers(flag_options)
# Install a signal handler that will shut down the ioloop
# and close all our threads
_set_up_signal_handler()
ioloop = tornado.ioloop.IOLoop.current()
# Create and start the server.
server = Server(ioloop, main_script_path, command_line)
server.start(_on_server_start)
# Start the ioloop. This function will not return until the
# server is shut down.
ioloop.start()