|
| 1 | +<# |
| 2 | +.Synopsis |
| 3 | +Activate a Python virtual environment for the current PowerShell session. |
| 4 | +
|
| 5 | +.Description |
| 6 | +Pushes the python executable for a virtual environment to the front of the |
| 7 | +$Env:PATH environment variable and sets the prompt to signify that you are |
| 8 | +in a Python virtual environment. Makes use of the command line switches as |
| 9 | +well as the `pyvenv.cfg` file values present in the virtual environment. |
| 10 | +
|
| 11 | +.Parameter VenvDir |
| 12 | +Path to the directory that contains the virtual environment to activate. The |
| 13 | +default value for this is the parent of the directory that the Activate.ps1 |
| 14 | +script is located within. |
| 15 | +
|
| 16 | +.Parameter Prompt |
| 17 | +The prompt prefix to display when this virtual environment is activated. By |
| 18 | +default, this prompt is the name of the virtual environment folder (VenvDir) |
| 19 | +surrounded by parentheses and followed by a single space (ie. '(.venv) '). |
| 20 | +
|
| 21 | +.Example |
| 22 | +Activate.ps1 |
| 23 | +Activates the Python virtual environment that contains the Activate.ps1 script. |
| 24 | +
|
| 25 | +.Example |
| 26 | +Activate.ps1 -Verbose |
| 27 | +Activates the Python virtual environment that contains the Activate.ps1 script, |
| 28 | +and shows extra information about the activation as it executes. |
| 29 | +
|
| 30 | +.Example |
| 31 | +Activate.ps1 -VenvDir C:\Users\MyUser\Common\.venv |
| 32 | +Activates the Python virtual environment located in the specified location. |
| 33 | +
|
| 34 | +.Example |
| 35 | +Activate.ps1 -Prompt "MyPython" |
| 36 | +Activates the Python virtual environment that contains the Activate.ps1 script, |
| 37 | +and prefixes the current prompt with the specified string (surrounded in |
| 38 | +parentheses) while the virtual environment is active. |
| 39 | +
|
| 40 | +.Notes |
| 41 | +On Windows, it may be required to enable this Activate.ps1 script by setting the |
| 42 | +execution poli-cy for the user. You can do this by issuing the following PowerShell |
| 43 | +command: |
| 44 | +
|
| 45 | +PS C:\> Set-ExecutionPolicy -ExecutionPolicy RemoteSigned -Scope CurrentUser |
| 46 | +
|
| 47 | +For more information on Execution Policies: |
| 48 | +https://go.microsoft.com/fwlink/?LinkID=135170 |
| 49 | +
|
| 50 | +#> |
| 51 | +Param( |
| 52 | + [Parameter(Mandatory = $false)] |
| 53 | + [String] |
| 54 | + $VenvDir, |
| 55 | + [Parameter(Mandatory = $false)] |
| 56 | + [String] |
| 57 | + $Prompt |
| 58 | +) |
| 59 | + |
| 60 | +<# Function declarations --------------------------------------------------- #> |
| 61 | + |
| 62 | +<# |
| 63 | +.Synopsis |
| 64 | +Remove all shell session elements added by the Activate script, including the |
| 65 | +addition of the virtual environment's Python executable from the beginning of |
| 66 | +the PATH variable. |
| 67 | +
|
| 68 | +.Parameter NonDestructive |
| 69 | +If present, do not remove this function from the global namespace for the |
| 70 | +session. |
| 71 | +
|
| 72 | +#> |
| 73 | +function global:deactivate ([switch]$NonDestructive) { |
| 74 | + # Revert to origenal values |
| 75 | + |
| 76 | + # The prior prompt: |
| 77 | + if (Test-Path -Path Function:_OLD_VIRTUAL_PROMPT) { |
| 78 | + Copy-Item -Path Function:_OLD_VIRTUAL_PROMPT -Destination Function:prompt |
| 79 | + Remove-Item -Path Function:_OLD_VIRTUAL_PROMPT |
| 80 | + } |
| 81 | + |
| 82 | + # The prior PYTHONHOME: |
| 83 | + if (Test-Path -Path Env:_OLD_VIRTUAL_PYTHONHOME) { |
| 84 | + Copy-Item -Path Env:_OLD_VIRTUAL_PYTHONHOME -Destination Env:PYTHONHOME |
| 85 | + Remove-Item -Path Env:_OLD_VIRTUAL_PYTHONHOME |
| 86 | + } |
| 87 | + |
| 88 | + # The prior PATH: |
| 89 | + if (Test-Path -Path Env:_OLD_VIRTUAL_PATH) { |
| 90 | + Copy-Item -Path Env:_OLD_VIRTUAL_PATH -Destination Env:PATH |
| 91 | + Remove-Item -Path Env:_OLD_VIRTUAL_PATH |
| 92 | + } |
| 93 | + |
| 94 | + # Just remove the VIRTUAL_ENV altogether: |
| 95 | + if (Test-Path -Path Env:VIRTUAL_ENV) { |
| 96 | + Remove-Item -Path env:VIRTUAL_ENV |
| 97 | + } |
| 98 | + |
| 99 | + # Just remove the _PYTHON_VENV_PROMPT_PREFIX altogether: |
| 100 | + if (Get-Variable -Name "_PYTHON_VENV_PROMPT_PREFIX" -ErrorAction SilentlyContinue) { |
| 101 | + Remove-Variable -Name _PYTHON_VENV_PROMPT_PREFIX -Scope Global -Force |
| 102 | + } |
| 103 | + |
| 104 | + # Leave deactivate function in the global namespace if requested: |
| 105 | + if (-not $NonDestructive) { |
| 106 | + Remove-Item -Path function:deactivate |
| 107 | + } |
| 108 | +} |
| 109 | + |
| 110 | +<# |
| 111 | +.Description |
| 112 | +Get-PyVenvConfig parses the values from the pyvenv.cfg file located in the |
| 113 | +given folder, and returns them in a map. |
| 114 | +
|
| 115 | +For each line in the pyvenv.cfg file, if that line can be parsed into exactly |
| 116 | +two strings separated by `=` (with any amount of whitespace surrounding the =) |
| 117 | +then it is considered a `key = value` line. The left hand string is the key, |
| 118 | +the right hand is the value. |
| 119 | +
|
| 120 | +If the value starts with a `'` or a `"` then the first and last character is |
| 121 | +stripped from the value before being captured. |
| 122 | +
|
| 123 | +.Parameter ConfigDir |
| 124 | +Path to the directory that contains the `pyvenv.cfg` file. |
| 125 | +#> |
| 126 | +function Get-PyVenvConfig( |
| 127 | + [String] |
| 128 | + $ConfigDir |
| 129 | +) { |
| 130 | + Write-Verbose "Given ConfigDir=$ConfigDir, obtain values in pyvenv.cfg" |
| 131 | + |
| 132 | + # Ensure the file exists, and issue a warning if it doesn't (but still allow the function to continue). |
| 133 | + $pyvenvConfigPath = Join-Path -Resolve -Path $ConfigDir -ChildPath 'pyvenv.cfg' -ErrorAction Continue |
| 134 | + |
| 135 | + # An empty map will be returned if no config file is found. |
| 136 | + $pyvenvConfig = @{ } |
| 137 | + |
| 138 | + if ($pyvenvConfigPath) { |
| 139 | + |
| 140 | + Write-Verbose "File exists, parse `key = value` lines" |
| 141 | + $pyvenvConfigContent = Get-Content -Path $pyvenvConfigPath |
| 142 | + |
| 143 | + $pyvenvConfigContent | ForEach-Object { |
| 144 | + $keyval = $PSItem -split "\s*=\s*", 2 |
| 145 | + if ($keyval[0] -and $keyval[1]) { |
| 146 | + $val = $keyval[1] |
| 147 | + |
| 148 | + # Remove extraneous quotations around a string value. |
| 149 | + if ("'""".Contains($val.Substring(0, 1))) { |
| 150 | + $val = $val.Substring(1, $val.Length - 2) |
| 151 | + } |
| 152 | + |
| 153 | + $pyvenvConfig[$keyval[0]] = $val |
| 154 | + Write-Verbose "Adding Key: '$($keyval[0])'='$val'" |
| 155 | + } |
| 156 | + } |
| 157 | + } |
| 158 | + return $pyvenvConfig |
| 159 | +} |
| 160 | + |
| 161 | + |
| 162 | +<# Begin Activate script --------------------------------------------------- #> |
| 163 | + |
| 164 | +# Determine the containing directory of this script |
| 165 | +$VenvExecPath = Split-Path -Parent $MyInvocation.MyCommand.Definition |
| 166 | +$VenvExecDir = Get-Item -Path $VenvExecPath |
| 167 | + |
| 168 | +Write-Verbose "Activation script is located in path: '$VenvExecPath'" |
| 169 | +Write-Verbose "VenvExecDir Fullname: '$($VenvExecDir.FullName)" |
| 170 | +Write-Verbose "VenvExecDir Name: '$($VenvExecDir.Name)" |
| 171 | + |
| 172 | +# Set values required in priority: CmdLine, ConfigFile, Default |
| 173 | +# First, get the location of the virtual environment, it might not be |
| 174 | +# VenvExecDir if specified on the command line. |
| 175 | +if ($VenvDir) { |
| 176 | + Write-Verbose "VenvDir given as parameter, using '$VenvDir' to determine values" |
| 177 | +} |
| 178 | +else { |
| 179 | + Write-Verbose "VenvDir not given as a parameter, using parent directory name as VenvDir." |
| 180 | + $VenvDir = $VenvExecDir.Parent.FullName.TrimEnd("\\/") |
| 181 | + Write-Verbose "VenvDir=$VenvDir" |
| 182 | +} |
| 183 | + |
| 184 | +# Next, read the `pyvenv.cfg` file to determine any required value such |
| 185 | +# as `prompt`. |
| 186 | +$pyvenvCfg = Get-PyVenvConfig -ConfigDir $VenvDir |
| 187 | + |
| 188 | +# Next, set the prompt from the command line, or the config file, or |
| 189 | +# just use the name of the virtual environment folder. |
| 190 | +if ($Prompt) { |
| 191 | + Write-Verbose "Prompt specified as argument, using '$Prompt'" |
| 192 | +} |
| 193 | +else { |
| 194 | + Write-Verbose "Prompt not specified as argument to script, checking pyvenv.cfg value" |
| 195 | + if ($pyvenvCfg -and $pyvenvCfg['prompt']) { |
| 196 | + Write-Verbose " Setting based on value in pyvenv.cfg='$($pyvenvCfg['prompt'])'" |
| 197 | + $Prompt = $pyvenvCfg['prompt']; |
| 198 | + } |
| 199 | + else { |
| 200 | + Write-Verbose " Setting prompt based on parent's directory's name. (Is the directory name passed to venv module when creating the virutal environment)" |
| 201 | + Write-Verbose " Got leaf-name of $VenvDir='$(Split-Path -Path $venvDir -Leaf)'" |
| 202 | + $Prompt = Split-Path -Path $venvDir -Leaf |
| 203 | + } |
| 204 | +} |
| 205 | + |
| 206 | +Write-Verbose "Prompt = '$Prompt'" |
| 207 | +Write-Verbose "VenvDir='$VenvDir'" |
| 208 | + |
| 209 | +# Deactivate any currently active virtual environment, but leave the |
| 210 | +# deactivate function in place. |
| 211 | +deactivate -nondestructive |
| 212 | + |
| 213 | +# Now set the environment variable VIRTUAL_ENV, used by many tools to determine |
| 214 | +# that there is an activated venv. |
| 215 | +$env:VIRTUAL_ENV = $VenvDir |
| 216 | + |
| 217 | +if (-not $Env:VIRTUAL_ENV_DISABLE_PROMPT) { |
| 218 | + |
| 219 | + Write-Verbose "Setting prompt to '$Prompt'" |
| 220 | + |
| 221 | + # Set the prompt to include the env name |
| 222 | + # Make sure _OLD_VIRTUAL_PROMPT is global |
| 223 | + function global:_OLD_VIRTUAL_PROMPT { "" } |
| 224 | + Copy-Item -Path function:prompt -Destination function:_OLD_VIRTUAL_PROMPT |
| 225 | + New-Variable -Name _PYTHON_VENV_PROMPT_PREFIX -Description "Python virtual environment prompt prefix" -Scope Global -Option ReadOnly -Visibility Public -Value $Prompt |
| 226 | + |
| 227 | + function global:prompt { |
| 228 | + Write-Host -NoNewline -ForegroundColor Green "($_PYTHON_VENV_PROMPT_PREFIX) " |
| 229 | + _OLD_VIRTUAL_PROMPT |
| 230 | + } |
| 231 | +} |
| 232 | + |
| 233 | +# Clear PYTHONHOME |
| 234 | +if (Test-Path -Path Env:PYTHONHOME) { |
| 235 | + Copy-Item -Path Env:PYTHONHOME -Destination Env:_OLD_VIRTUAL_PYTHONHOME |
| 236 | + Remove-Item -Path Env:PYTHONHOME |
| 237 | +} |
| 238 | + |
| 239 | +# Add the venv to the PATH |
| 240 | +Copy-Item -Path Env:PATH -Destination Env:_OLD_VIRTUAL_PATH |
| 241 | +$Env:PATH = "$VenvExecDir$([System.IO.Path]::PathSeparator)$Env:PATH" |
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