Automation
While convenient, I’d like it even better were I not be required to remember to run this script every time I open a project. Visual Studio Code’s automation capabilities, offered through tasks, come in useful. Here’s what I need to consider when opening a project.
- The virtual environment from the last time I worked on this project might still be lingering about.
- Temporary folders such as
__pycache__ and .ipynb_checkpoints from my previous development session need to be cleaned up.
- A brainwave during the night might entail adding new packages to
requirements.txt
- And, of course, I need to remember to run the
build script
These folders aren’t trivial and, depending on the size and number of projects, take up space on my workstation. I’d prefer to not even have my projects sit in my workstation anyways, isn’t that what GitHub is for?
Tasks help you automate routine activities in Visual Studio Code. Tasks can be folder-specific or workspace-specific and can call additional scripts upon certain triggers (such as opening a folder for instance). Tasks can also be sequenced.
Create a Python program which resides in a scripts folder in your project (you may choose to even have this reside in build but I like to keep them separate). An example is shown here.
from pathlib import Path
import shutil
root = Path(__file__).resolve().parents[1]
delete_dirs = {"__pycache__", ".ipynb_checkpoints", ".pytest_cache", "buildproj", "node_modules"}
delete_files = {".DS_Store"}
for path in root.rglob("*"):
if path.is_dir() and path.name in delete_dirs:
shutil.rmtree(path, ignore_errors=True)
elif path.is_file():
if path.name in delete_files or path.suffix == ".pyc":
try:
path.unlink()
except FileNotFoundError:
pass
This program searches for specified directories and files anywhere within the repository and deletes them. I have included common files which I do not require (since I shall probably be recreating them as I develop).
Next, create a folder called .vscode (it may already exist) in the root folder of your project and add a tasks.json there. If a tasks.json exists, it’s possible that you already know how to define a task and in this case, would be adding one more. Here’s the block to add to your tasks.json.
{
"version": "2.0.0",
"tasks": [
{
"label": "Clean Python cache",
"type": "shell",
"command": "python",
"args": [
"${workspaceFolder}/scripts/clean_cache.py"
],
"runOptions": {
"runOn": "folderOpen"
},
"presentation": {
"reveal": "never",
"panel": "shared"
},
"problemMatcher": []
}
]
}
This is only the first task. Simply expressed, it runs every time this folder ( ${workspaceFolder} ) is opened and executes a Python program (the one above) that cleans up unwanted folders and files. Tasks can also be configured through the command palette of Visual Studio Code.
The second task, which you would ideally want to have run after the first task is as follows. This may also be added to the tasks list in the tasks.jsonfile above.
{
"label": "build_environment",
"type": "shell",
"command": "cd build && ./build.sh",
"args": [
],
"dependsOn": "Clean Python cache",
"dependsOrder": "sequence",
"runOptions": {
"runOn": "folderOpen"
},
"presentation": {
"reveal": "always",
"panel": "shared"
},
"problemMatcher": []
}
Once you’ve deleted unwanted files and folders, you can proceed with building the environment afresh. Note the additional options here: dependsOn and dependsOrder . dependsOn specifies that the build_environmenttask depends on the successful run of the Clean Python cache task. dependsOrder specifies that this should run in sequence, i.e. after Clean Python cache. The final tasks.json is as follows.
{
"version": "2.0.0",
"tasks": [
{
"label": "Clean Python cache",
"type": "shell",
"command": "python",
"args": [
"${workspaceFolder}/scripts/clean_cache.py"
],
"runOptions": {
"runOn": "folderOpen"
},
"presentation": {
"reveal": "never",
"panel": "shared"
},
"problemMatcher": []
},
{
"label": "build_environment",
"type": "shell",
"command": "cd build && ./build.sh",
"args": [
],
"dependsOn": "Clean Python cache",
"dependsOrder": "sequence",
"runOptions": {
"runOn": "folderOpen"
},
"presentation": {
"reveal": "always",
"panel": "shared"
},
"problemMatcher": []
}
]
}
Test this by closing (File -> Close Folder) and then reopening the project folder. Be prepared to show a little patience the first time as waiting for the task to complete may take some getting used to.
Be aware of the tradeoffs. Depending on their complexity, tasks may run for some time and you may need to wait a short while after opening the folder to commence your work. Also, some projects with complex dependencies and heavy packages might be better off left alone without having to rebuild them every time. Your configuration is a carefully crafted context-contingent choice.
