File size: 3,532 Bytes
ff2b8e3 |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 |
"""Adds pre-session state to StreamLit.
This file is borrowed from
https://gist.github.com/tvst/036da038ab3e999a64497f42de966a92
"""
# pylint: disable=protected-access
try:
import streamlit.ReportThread as ReportThread
from streamlit.server.Server import Server
except ModuleNotFoundError:
# Streamlit >= 0.65.0
import streamlit.report_thread as ReportThread
from streamlit.server.server import Server
class SessionState(object):
"""Hack to add per-session state to Streamlit.
Usage
-----
>>> import SessionState
>>>
>>> session_state = SessionState.get(user_name='', favorite_color='black')
>>> session_state.user_name
''
>>> session_state.user_name = 'Mary'
>>> session_state.favorite_color
'black'
Since you set user_name above, next time your script runs this will be the
result:
>>> session_state = get(user_name='', favorite_color='black')
>>> session_state.user_name
'Mary'
"""
def __init__(self, **kwargs):
"""A new SessionState object.
Parameters
----------
**kwargs : any
Default values for the session state.
Example
-------
>>> session_state = SessionState(user_name='', favorite_color='black')
>>> session_state.user_name = 'Mary'
''
>>> session_state.favorite_color
'black'
"""
for key, val in kwargs.items():
setattr(self, key, val)
def get(**kwargs):
"""Gets a SessionState object for the current session.
Creates a new object if necessary.
Parameters
----------
**kwargs : any
Default values you want to add to the session state, if we're creating a
new one.
Example
-------
>>> session_state = get(user_name='', favorite_color='black')
>>> session_state.user_name
''
>>> session_state.user_name = 'Mary'
>>> session_state.favorite_color
'black'
Since you set user_name above, next time your script runs this will be the
result:
>>> session_state = get(user_name='', favorite_color='black')
>>> session_state.user_name
'Mary'
"""
# Hack to get the session object from Streamlit.
ctx = ReportThread.get_report_ctx()
this_session = None
current_server = Server.get_current()
if hasattr(current_server, '_session_infos'):
# Streamlit < 0.56
session_infos = Server.get_current()._session_infos.values()
else:
session_infos = Server.get_current()._session_info_by_id.values()
for session_info in session_infos:
s = session_info.session
if (
# Streamlit < 0.54.0
(hasattr(s, '_main_dg') and s._main_dg == ctx.main_dg)
or
# Streamlit >= 0.54.0
(not hasattr(s, '_main_dg') and s.enqueue == ctx.enqueue)
or
# Streamlit >= 0.65.2
(not hasattr(s, '_main_dg') and
s._uploaded_file_mgr == ctx.uploaded_file_mgr)
):
this_session = s
if this_session is None:
raise RuntimeError(
"Oh noes. Couldn't get your Streamlit Session object. "
'Are you doing something fancy with threads?')
# Got the session object! Now let's attach some state into it.
if not hasattr(this_session, '_custom_session_state'):
this_session._custom_session_state = SessionState(**kwargs)
return this_session._custom_session_state
# pylint: enable=protected-access
|