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table, th, td {
border: 1px solid black;
border-style: dotted;
border-collapse: collapse;
padding: 10px;
}
#canvasWrapper {
position: relative;
padding: 10px;
margin: 10px;
}
canvas {
position: absolute;
}
from flask import Flask
import json
app = Flask(__name__)
@app.route("/")
def hello_world():
return "<p>Hello, World!</p>"
@app.route("/getJSON")
def getJSON():
data = {
"A" : {
"0" : ["x", "y", "z"],
"1" : ["x", "y", "z"],
"2" : ["x", "y", "z"],
"3" : ["x", "y", "z"],
"4" : ["x", "y", "z"],
},
"B" : {
"0" : ["x", "y", "z"],
"1" : ["x", "y", "z"],
"2" : ["x", "y", "z"],
"3" : ["x", "y", "z"],
"4" : ["x", "y", "z"],
"5" : ["x", "y", "z"],
},
"C" : {
"0" : ["x", "y", "z"],
"1" : ["x", "y", "z"],
"2" : ["x", "y", "z"],
},
"D" : {
"0" : ["x", "y", "z"],
"1" : ["x", "y", "z"],
"2" : ["x", "y", "z"],
"3" : ["x", "y", "z"],
"4" : ["x", "y", "z"],
"5" : ["x", "y", "z"],
"6" : ["x", "y", "z"]
}
}
return json.dumps(data)
if __name__ == "__main__":
app.run()
\ No newline at end of file
<#
.Synopsis
Activate a Python virtual environment for the current PowerShell session.
.Description
Pushes the python executable for a virtual environment to the front of the
$Env:PATH environment variable and sets the prompt to signify that you are
in a Python virtual environment. Makes use of the command line switches as
well as the `pyvenv.cfg` file values present in the virtual environment.
.Parameter VenvDir
Path to the directory that contains the virtual environment to activate. The
default value for this is the parent of the directory that the Activate.ps1
script is located within.
.Parameter Prompt
The prompt prefix to display when this virtual environment is activated. By
default, this prompt is the name of the virtual environment folder (VenvDir)
surrounded by parentheses and followed by a single space (ie. '(.venv) ').
.Example
Activate.ps1
Activates the Python virtual environment that contains the Activate.ps1 script.
.Example
Activate.ps1 -Verbose
Activates the Python virtual environment that contains the Activate.ps1 script,
and shows extra information about the activation as it executes.
.Example
Activate.ps1 -VenvDir C:\Users\MyUser\Common\.venv
Activates the Python virtual environment located in the specified location.
.Example
Activate.ps1 -Prompt "MyPython"
Activates the Python virtual environment that contains the Activate.ps1 script,
and prefixes the current prompt with the specified string (surrounded in
parentheses) while the virtual environment is active.
.Notes
On Windows, it may be required to enable this Activate.ps1 script by setting the
execution policy for the user. You can do this by issuing the following PowerShell
command:
PS C:\> Set-ExecutionPolicy -ExecutionPolicy RemoteSigned -Scope CurrentUser
For more information on Execution Policies:
https://go.microsoft.com/fwlink/?LinkID=135170
#>
Param(
[Parameter(Mandatory = $false)]
[String]
$VenvDir,
[Parameter(Mandatory = $false)]
[String]
$Prompt
)
<# Function declarations --------------------------------------------------- #>
<#
.Synopsis
Remove all shell session elements added by the Activate script, including the
addition of the virtual environment's Python executable from the beginning of
the PATH variable.
.Parameter NonDestructive
If present, do not remove this function from the global namespace for the
session.
#>
function global:deactivate ([switch]$NonDestructive) {
# Revert to original values
# The prior prompt:
if (Test-Path -Path Function:_OLD_VIRTUAL_PROMPT) {
Copy-Item -Path Function:_OLD_VIRTUAL_PROMPT -Destination Function:prompt
Remove-Item -Path Function:_OLD_VIRTUAL_PROMPT
}
# The prior PYTHONHOME:
if (Test-Path -Path Env:_OLD_VIRTUAL_PYTHONHOME) {
Copy-Item -Path Env:_OLD_VIRTUAL_PYTHONHOME -Destination Env:PYTHONHOME
Remove-Item -Path Env:_OLD_VIRTUAL_PYTHONHOME
}
# The prior PATH:
if (Test-Path -Path Env:_OLD_VIRTUAL_PATH) {
Copy-Item -Path Env:_OLD_VIRTUAL_PATH -Destination Env:PATH
Remove-Item -Path Env:_OLD_VIRTUAL_PATH
}
# Just remove the VIRTUAL_ENV altogether:
if (Test-Path -Path Env:VIRTUAL_ENV) {
Remove-Item -Path env:VIRTUAL_ENV
}
# Just remove VIRTUAL_ENV_PROMPT altogether.
if (Test-Path -Path Env:VIRTUAL_ENV_PROMPT) {
Remove-Item -Path env:VIRTUAL_ENV_PROMPT
}
# Just remove the _PYTHON_VENV_PROMPT_PREFIX altogether:
if (Get-Variable -Name "_PYTHON_VENV_PROMPT_PREFIX" -ErrorAction SilentlyContinue) {
Remove-Variable -Name _PYTHON_VENV_PROMPT_PREFIX -Scope Global -Force
}
# Leave deactivate function in the global namespace if requested:
if (-not $NonDestructive) {
Remove-Item -Path function:deactivate
}
}
<#
.Description
Get-PyVenvConfig parses the values from the pyvenv.cfg file located in the
given folder, and returns them in a map.
For each line in the pyvenv.cfg file, if that line can be parsed into exactly
two strings separated by `=` (with any amount of whitespace surrounding the =)
then it is considered a `key = value` line. The left hand string is the key,
the right hand is the value.
If the value starts with a `'` or a `"` then the first and last character is
stripped from the value before being captured.
.Parameter ConfigDir
Path to the directory that contains the `pyvenv.cfg` file.
#>
function Get-PyVenvConfig(
[String]
$ConfigDir
) {
Write-Verbose "Given ConfigDir=$ConfigDir, obtain values in pyvenv.cfg"
# Ensure the file exists, and issue a warning if it doesn't (but still allow the function to continue).
$pyvenvConfigPath = Join-Path -Resolve -Path $ConfigDir -ChildPath 'pyvenv.cfg' -ErrorAction Continue
# An empty map will be returned if no config file is found.
$pyvenvConfig = @{ }
if ($pyvenvConfigPath) {
Write-Verbose "File exists, parse `key = value` lines"
$pyvenvConfigContent = Get-Content -Path $pyvenvConfigPath
$pyvenvConfigContent | ForEach-Object {
$keyval = $PSItem -split "\s*=\s*", 2
if ($keyval[0] -and $keyval[1]) {
$val = $keyval[1]
# Remove extraneous quotations around a string value.
if ("'""".Contains($val.Substring(0, 1))) {
$val = $val.Substring(1, $val.Length - 2)
}
$pyvenvConfig[$keyval[0]] = $val
Write-Verbose "Adding Key: '$($keyval[0])'='$val'"
}
}
}
return $pyvenvConfig
}
<# Begin Activate script --------------------------------------------------- #>
# Determine the containing directory of this script
$VenvExecPath = Split-Path -Parent $MyInvocation.MyCommand.Definition
$VenvExecDir = Get-Item -Path $VenvExecPath
Write-Verbose "Activation script is located in path: '$VenvExecPath'"
Write-Verbose "VenvExecDir Fullname: '$($VenvExecDir.FullName)"
Write-Verbose "VenvExecDir Name: '$($VenvExecDir.Name)"
# Set values required in priority: CmdLine, ConfigFile, Default
# First, get the location of the virtual environment, it might not be
# VenvExecDir if specified on the command line.
if ($VenvDir) {
Write-Verbose "VenvDir given as parameter, using '$VenvDir' to determine values"
}
else {
Write-Verbose "VenvDir not given as a parameter, using parent directory name as VenvDir."
$VenvDir = $VenvExecDir.Parent.FullName.TrimEnd("\\/")
Write-Verbose "VenvDir=$VenvDir"
}
# Next, read the `pyvenv.cfg` file to determine any required value such
# as `prompt`.
$pyvenvCfg = Get-PyVenvConfig -ConfigDir $VenvDir
# Next, set the prompt from the command line, or the config file, or
# just use the name of the virtual environment folder.
if ($Prompt) {
Write-Verbose "Prompt specified as argument, using '$Prompt'"
}
else {
Write-Verbose "Prompt not specified as argument to script, checking pyvenv.cfg value"
if ($pyvenvCfg -and $pyvenvCfg['prompt']) {
Write-Verbose " Setting based on value in pyvenv.cfg='$($pyvenvCfg['prompt'])'"
$Prompt = $pyvenvCfg['prompt'];
}
else {
Write-Verbose " Setting prompt based on parent's directory's name. (Is the directory name passed to venv module when creating the virtual environment)"
Write-Verbose " Got leaf-name of $VenvDir='$(Split-Path -Path $venvDir -Leaf)'"
$Prompt = Split-Path -Path $venvDir -Leaf
}
}
Write-Verbose "Prompt = '$Prompt'"
Write-Verbose "VenvDir='$VenvDir'"
# Deactivate any currently active virtual environment, but leave the
# deactivate function in place.
deactivate -nondestructive
# Now set the environment variable VIRTUAL_ENV, used by many tools to determine
# that there is an activated venv.
$env:VIRTUAL_ENV = $VenvDir
if (-not $Env:VIRTUAL_ENV_DISABLE_PROMPT) {
Write-Verbose "Setting prompt to '$Prompt'"
# Set the prompt to include the env name
# Make sure _OLD_VIRTUAL_PROMPT is global
function global:_OLD_VIRTUAL_PROMPT { "" }
Copy-Item -Path function:prompt -Destination function:_OLD_VIRTUAL_PROMPT
New-Variable -Name _PYTHON_VENV_PROMPT_PREFIX -Description "Python virtual environment prompt prefix" -Scope Global -Option ReadOnly -Visibility Public -Value $Prompt
function global:prompt {
Write-Host -NoNewline -ForegroundColor Green "($_PYTHON_VENV_PROMPT_PREFIX) "
_OLD_VIRTUAL_PROMPT
}
$env:VIRTUAL_ENV_PROMPT = $Prompt
}
# Clear PYTHONHOME
if (Test-Path -Path Env:PYTHONHOME) {
Copy-Item -Path Env:PYTHONHOME -Destination Env:_OLD_VIRTUAL_PYTHONHOME
Remove-Item -Path Env:PYTHONHOME
}
# Add the venv to the PATH
Copy-Item -Path Env:PATH -Destination Env:_OLD_VIRTUAL_PATH
$Env:PATH = "$VenvExecDir$([System.IO.Path]::PathSeparator)$Env:PATH"
# This file must be used with "source bin/activate" *from bash*
# you cannot run it directly
deactivate () {
# reset old environment variables
if [ -n "${_OLD_VIRTUAL_PATH:-}" ] ; then
PATH="${_OLD_VIRTUAL_PATH:-}"
export PATH
unset _OLD_VIRTUAL_PATH
fi
if [ -n "${_OLD_VIRTUAL_PYTHONHOME:-}" ] ; then
PYTHONHOME="${_OLD_VIRTUAL_PYTHONHOME:-}"
export PYTHONHOME
unset _OLD_VIRTUAL_PYTHONHOME
fi
# This should detect bash and zsh, which have a hash command that must
# be called to get it to forget past commands. Without forgetting
# past commands the $PATH changes we made may not be respected
if [ -n "${BASH:-}" -o -n "${ZSH_VERSION:-}" ] ; then
hash -r 2> /dev/null
fi
if [ -n "${_OLD_VIRTUAL_PS1:-}" ] ; then
PS1="${_OLD_VIRTUAL_PS1:-}"
export PS1
unset _OLD_VIRTUAL_PS1
fi
unset VIRTUAL_ENV
unset VIRTUAL_ENV_PROMPT
if [ ! "${1:-}" = "nondestructive" ] ; then
# Self destruct!
unset -f deactivate
fi
}
# unset irrelevant variables
deactivate nondestructive
VIRTUAL_ENV="/Users/sam/Documents/Documents/BU/EC504/FinalProjFrontEnd/server/venv"
export VIRTUAL_ENV
_OLD_VIRTUAL_PATH="$PATH"
PATH="$VIRTUAL_ENV/bin:$PATH"
export PATH
# unset PYTHONHOME if set
# this will fail if PYTHONHOME is set to the empty string (which is bad anyway)
# could use `if (set -u; : $PYTHONHOME) ;` in bash
if [ -n "${PYTHONHOME:-}" ] ; then
_OLD_VIRTUAL_PYTHONHOME="${PYTHONHOME:-}"
unset PYTHONHOME
fi
if [ -z "${VIRTUAL_ENV_DISABLE_PROMPT:-}" ] ; then
_OLD_VIRTUAL_PS1="${PS1:-}"
PS1="(venv) ${PS1:-}"
export PS1
VIRTUAL_ENV_PROMPT="(venv) "
export VIRTUAL_ENV_PROMPT
fi
# This should detect bash and zsh, which have a hash command that must
# be called to get it to forget past commands. Without forgetting
# past commands the $PATH changes we made may not be respected
if [ -n "${BASH:-}" -o -n "${ZSH_VERSION:-}" ] ; then
hash -r 2> /dev/null
fi
# This file must be used with "source bin/activate.csh" *from csh*.
# You cannot run it directly.
# Created by Davide Di Blasi <davidedb@gmail.com>.
# Ported to Python 3.3 venv by Andrew Svetlov <andrew.svetlov@gmail.com>
alias deactivate 'test $?_OLD_VIRTUAL_PATH != 0 && setenv PATH "$_OLD_VIRTUAL_PATH" && unset _OLD_VIRTUAL_PATH; rehash; test $?_OLD_VIRTUAL_PROMPT != 0 && set prompt="$_OLD_VIRTUAL_PROMPT" && unset _OLD_VIRTUAL_PROMPT; unsetenv VIRTUAL_ENV; unsetenv VIRTUAL_ENV_PROMPT; test "\!:*" != "nondestructive" && unalias deactivate'
# Unset irrelevant variables.
deactivate nondestructive
setenv VIRTUAL_ENV "/Users/sam/Documents/Documents/BU/EC504/FinalProjFrontEnd/server/venv"
set _OLD_VIRTUAL_PATH="$PATH"
setenv PATH "$VIRTUAL_ENV/bin:$PATH"
set _OLD_VIRTUAL_PROMPT="$prompt"
if (! "$?VIRTUAL_ENV_DISABLE_PROMPT") then
set prompt = "(venv) $prompt"
setenv VIRTUAL_ENV_PROMPT "(venv) "
endif
alias pydoc python -m pydoc
rehash
# This file must be used with "source <venv>/bin/activate.fish" *from fish*
# (https://fishshell.com/); you cannot run it directly.
function deactivate -d "Exit virtual environment and return to normal shell environment"
# reset old environment variables
if test -n "$_OLD_VIRTUAL_PATH"
set -gx PATH $_OLD_VIRTUAL_PATH
set -e _OLD_VIRTUAL_PATH
end
if test -n "$_OLD_VIRTUAL_PYTHONHOME"
set -gx PYTHONHOME $_OLD_VIRTUAL_PYTHONHOME
set -e _OLD_VIRTUAL_PYTHONHOME
end
if test -n "$_OLD_FISH_PROMPT_OVERRIDE"
set -e _OLD_FISH_PROMPT_OVERRIDE
# prevents error when using nested fish instances (Issue #93858)
if functions -q _old_fish_prompt
functions -e fish_prompt
functions -c _old_fish_prompt fish_prompt
functions -e _old_fish_prompt
end
end
set -e VIRTUAL_ENV
set -e VIRTUAL_ENV_PROMPT
if test "$argv[1]" != "nondestructive"
# Self-destruct!
functions -e deactivate
end
end
# Unset irrelevant variables.
deactivate nondestructive
set -gx VIRTUAL_ENV "/Users/sam/Documents/Documents/BU/EC504/FinalProjFrontEnd/server/venv"
set -gx _OLD_VIRTUAL_PATH $PATH
set -gx PATH "$VIRTUAL_ENV/bin" $PATH
# Unset PYTHONHOME if set.
if set -q PYTHONHOME
set -gx _OLD_VIRTUAL_PYTHONHOME $PYTHONHOME
set -e PYTHONHOME
end
if test -z "$VIRTUAL_ENV_DISABLE_PROMPT"
# fish uses a function instead of an env var to generate the prompt.
# Save the current fish_prompt function as the function _old_fish_prompt.
functions -c fish_prompt _old_fish_prompt
# With the original prompt function renamed, we can override with our own.
function fish_prompt
# Save the return status of the last command.
set -l old_status $status
# Output the venv prompt; color taken from the blue of the Python logo.
printf "%s%s%s" (set_color 4B8BBE) "(venv) " (set_color normal)
# Restore the return status of the previous command.
echo "exit $old_status" | .
# Output the original/"old" prompt.
_old_fish_prompt
end
set -gx _OLD_FISH_PROMPT_OVERRIDE "$VIRTUAL_ENV"
set -gx VIRTUAL_ENV_PROMPT "(venv) "
end
#!/Users/sam/Documents/Documents/BU/EC504/FinalProjFrontEnd/server/venv/bin/python3
# -*- coding: utf-8 -*-
import re
import sys
from flask.cli import main
if __name__ == '__main__':
sys.argv[0] = re.sub(r'(-script\.pyw|\.exe)?$', '', sys.argv[0])
sys.exit(main())
#!/Users/sam/Documents/Documents/BU/EC504/FinalProjFrontEnd/server/venv/bin/python3
# -*- coding: utf-8 -*-
import re
import sys
from pip._internal.cli.main import main
if __name__ == '__main__':
sys.argv[0] = re.sub(r'(-script\.pyw|\.exe)?$', '', sys.argv[0])
sys.exit(main())
#!/Users/sam/Documents/Documents/BU/EC504/FinalProjFrontEnd/server/venv/bin/python3
# -*- coding: utf-8 -*-
import re
import sys
from pip._internal.cli.main import main
if __name__ == '__main__':
sys.argv[0] = re.sub(r'(-script\.pyw|\.exe)?$', '', sys.argv[0])
sys.exit(main())
#!/Users/sam/Documents/Documents/BU/EC504/FinalProjFrontEnd/server/venv/bin/python3
# -*- coding: utf-8 -*-
import re
import sys
from pip._internal.cli.main import main
if __name__ == '__main__':
sys.argv[0] = re.sub(r'(-script\.pyw|\.exe)?$', '', sys.argv[0])
sys.exit(main())
/Library/Frameworks/Python.framework/Versions/3.10/bin/python3
\ No newline at end of file
from blinker.base import ANY
from blinker.base import NamedSignal
from blinker.base import Namespace
from blinker.base import receiver_connected
from blinker.base import Signal
from blinker.base import signal
from blinker.base import WeakNamespace
__all__ = [
"ANY",
"NamedSignal",
"Namespace",
"Signal",
"WeakNamespace",
"receiver_connected",
"signal",
]
__version__ = "1.7.0"
# extracted from Louie, http://pylouie.org/
# updated for Python 3
#
# Copyright (c) 2006 Patrick K. O'Brien, Mike C. Fletcher,
# Matthew R. Scott
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions are
# met:
#
# * Redistributions of source code must retain the above copyright
# notice, this list of conditions and the following disclaimer.
#
# * Redistributions in binary form must reproduce the above
# copyright notice, this list of conditions and the following
# disclaimer in the documentation and/or other materials provided
# with the distribution.
#
# * Neither the name of the <ORGANIZATION> nor the names of its
# contributors may be used to endorse or promote products derived
# from this software without specific prior written permission.
#
# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#
"""Refactored 'safe reference from dispatcher.py"""
import operator
import sys
import traceback
import weakref
get_self = operator.attrgetter("__self__")
get_func = operator.attrgetter("__func__")
def safe_ref(target, on_delete=None):
"""Return a *safe* weak reference to a callable target.
- ``target``: The object to be weakly referenced, if it's a bound
method reference, will create a BoundMethodWeakref, otherwise
creates a simple weakref.
- ``on_delete``: If provided, will have a hard reference stored to
the callable to be called after the safe reference goes out of
scope with the reference object, (either a weakref or a
BoundMethodWeakref) as argument.
"""
try:
im_self = get_self(target)
except AttributeError:
if callable(on_delete):
return weakref.ref(target, on_delete)
else:
return weakref.ref(target)
else:
if im_self is not None:
# Turn a bound method into a BoundMethodWeakref instance.
# Keep track of these instances for lookup by disconnect().
assert hasattr(target, "im_func") or hasattr(target, "__func__"), (
f"safe_ref target {target!r} has im_self, but no im_func, "
"don't know how to create reference"
)
reference = BoundMethodWeakref(target=target, on_delete=on_delete)
return reference
class BoundMethodWeakref:
"""'Safe' and reusable weak references to instance methods.
BoundMethodWeakref objects provide a mechanism for referencing a
bound method without requiring that the method object itself
(which is normally a transient object) is kept alive. Instead,
the BoundMethodWeakref object keeps weak references to both the
object and the function which together define the instance method.
Attributes:
- ``key``: The identity key for the reference, calculated by the
class's calculate_key method applied to the target instance method.
- ``deletion_methods``: Sequence of callable objects taking single
argument, a reference to this object which will be called when
*either* the target object or target function is garbage
collected (i.e. when this object becomes invalid). These are
specified as the on_delete parameters of safe_ref calls.
- ``weak_self``: Weak reference to the target object.
- ``weak_func``: Weak reference to the target function.
Class Attributes:
- ``_all_instances``: Class attribute pointing to all live
BoundMethodWeakref objects indexed by the class's
calculate_key(target) method applied to the target objects.
This weak value dictionary is used to short-circuit creation so
that multiple references to the same (object, function) pair
produce the same BoundMethodWeakref instance.
"""
_all_instances = weakref.WeakValueDictionary() # type: ignore[var-annotated]
def __new__(cls, target, on_delete=None, *arguments, **named):
"""Create new instance or return current instance.
Basically this method of construction allows us to
short-circuit creation of references to already-referenced
instance methods. The key corresponding to the target is
calculated, and if there is already an existing reference,
that is returned, with its deletion_methods attribute updated.
Otherwise the new instance is created and registered in the
table of already-referenced methods.
"""
key = cls.calculate_key(target)
current = cls._all_instances.get(key)
if current is not None:
current.deletion_methods.append(on_delete)
return current
else:
base = super().__new__(cls)
cls._all_instances[key] = base
base.__init__(target, on_delete, *arguments, **named)
return base
def __init__(self, target, on_delete=None):
"""Return a weak-reference-like instance for a bound method.
- ``target``: The instance-method target for the weak reference,
must have im_self and im_func attributes and be
reconstructable via the following, which is true of built-in
instance methods::
target.im_func.__get__( target.im_self )
- ``on_delete``: Optional callback which will be called when
this weak reference ceases to be valid (i.e. either the
object or the function is garbage collected). Should take a
single argument, which will be passed a pointer to this
object.
"""
def remove(weak, self=self):
"""Set self.isDead to True when method or instance is destroyed."""
methods = self.deletion_methods[:]
del self.deletion_methods[:]
try:
del self.__class__._all_instances[self.key]
except KeyError:
pass
for function in methods:
try:
if callable(function):
function(self)
except Exception:
try:
traceback.print_exc()
except AttributeError:
e = sys.exc_info()[1]
print(
f"Exception during saferef {self} "
f"cleanup function {function}: {e}"
)
self.deletion_methods = [on_delete]
self.key = self.calculate_key(target)
im_self = get_self(target)
im_func = get_func(target)
self.weak_self = weakref.ref(im_self, remove)
self.weak_func = weakref.ref(im_func, remove)
self.self_name = str(im_self)
self.func_name = str(im_func.__name__)
@classmethod
def calculate_key(cls, target):
"""Calculate the reference key for this reference.
Currently this is a two-tuple of the id()'s of the target
object and the target function respectively.
"""
return (id(get_self(target)), id(get_func(target)))
def __str__(self):
"""Give a friendly representation of the object."""
return "{}({}.{})".format(
self.__class__.__name__,
self.self_name,
self.func_name,
)
__repr__ = __str__
def __hash__(self):
return hash((self.self_name, self.key))
def __nonzero__(self):
"""Whether we are still a valid reference."""
return self() is not None
def __eq__(self, other):
"""Compare with another reference."""
if not isinstance(other, self.__class__):
return operator.eq(self.__class__, type(other))
return operator.eq(self.key, other.key)
def __call__(self):
"""Return a strong reference to the bound method.
If the target cannot be retrieved, then will return None,
otherwise returns a bound instance method for our object and
function.
Note: You may call this method any number of times, as it does
not invalidate the reference.
"""
target = self.weak_self()
if target is not None:
function = self.weak_func()
if function is not None:
return function.__get__(target)
return None
from __future__ import annotations
import typing as t
from weakref import ref
from blinker._saferef import BoundMethodWeakref
IdentityType = t.Union[t.Tuple[int, int], str, int]
class _symbol:
def __init__(self, name):
"""Construct a new named symbol."""
self.__name__ = self.name = name
def __reduce__(self):
return symbol, (self.name,)
def __repr__(self):
return self.name
_symbol.__name__ = "symbol"
class symbol:
"""A constant symbol.
>>> symbol('foo') is symbol('foo')
True
>>> symbol('foo')
foo
A slight refinement of the MAGICCOOKIE=object() pattern. The primary
advantage of symbol() is its repr(). They are also singletons.
Repeated calls of symbol('name') will all return the same instance.
"""
symbols = {} # type: ignore[var-annotated]
def __new__(cls, name):
try:
return cls.symbols[name]
except KeyError:
return cls.symbols.setdefault(name, _symbol(name))
def hashable_identity(obj: object) -> IdentityType:
if hasattr(obj, "__func__"):
return (id(obj.__func__), id(obj.__self__)) # type: ignore[attr-defined]
elif hasattr(obj, "im_func"):
return (id(obj.im_func), id(obj.im_self)) # type: ignore[attr-defined]
elif isinstance(obj, (int, str)):
return obj
else:
return id(obj)
WeakTypes = (ref, BoundMethodWeakref)
class annotatable_weakref(ref):
"""A weakref.ref that supports custom instance attributes."""
receiver_id: t.Optional[IdentityType]
sender_id: t.Optional[IdentityType]
def reference( # type: ignore[no-untyped-def]
object, callback=None, **annotations
) -> annotatable_weakref:
"""Return an annotated weak ref."""
if callable(object):
weak = callable_reference(object, callback)
else:
weak = annotatable_weakref(object, callback)
for key, value in annotations.items():
setattr(weak, key, value)
return weak # type: ignore[no-any-return]
def callable_reference(object, callback=None):
"""Return an annotated weak ref, supporting bound instance methods."""
if hasattr(object, "im_self") and object.im_self is not None:
return BoundMethodWeakref(target=object, on_delete=callback)
elif hasattr(object, "__self__") and object.__self__ is not None:
return BoundMethodWeakref(target=object, on_delete=callback)
return annotatable_weakref(object, callback)
class lazy_property:
"""A @property that is only evaluated once."""
def __init__(self, deferred):
self._deferred = deferred
self.__doc__ = deferred.__doc__
def __get__(self, obj, cls):
if obj is None:
return self
value = self._deferred(obj)
setattr(obj, self._deferred.__name__, value)
return value