Python Virtual Environments

# ===== Membuat virtual environment =====

# Nama konvensi: .venv atau venv
python3 -m venv .venv

# Dengan Python versi spesifik
python3.11 -m venv .venv
python3.12 -m venv .venv

# Dengan pip versi terbaru
python3 -m venv --upgrade-deps .venv

# Tanpa pip (hemat space)
python3 -m venv --without-pip .venv

# ===== Mengaktifkan virtual environment =====

# Linux / macOS:
source .venv/bin/activate

# Windows (Command Prompt):
.venv\Scripts\activate.bat

# Windows (PowerShell):
.venv\Scripts\Activate.ps1

# Windows (Git Bash):
source .venv/Scripts/activate

# ===== Setelah aktif, prompt berubah =====
# (.venv) user@machine:~/project$

# ===== Verifikasi =====
which python    # → /home/user/project/.venv/bin/python
which pip       # → /home/user/project/.venv/bin/pip
python --version

# ===== Deactivate =====
deactivate

# ===== Menghapus virtual environment =====
rm -rf .venv         # Linux/Mac
rmdir /s /q .venv    # Windows

# Struktur folder venv (Linux/macOS):
.venv/
├── bin/
│   ├── activate        # Script aktivasi (bash)
│   ├── activate.csh    # Script aktivasi (csh)
│   ├── activate.fish   # Script aktivasi (fish)
│   ├── python          # Symlink ke Python interpreter
│   ├── python3         # Symlink ke Python interpreter
│   └── pip             # pip executable
├── include/            # Header files (C extensions)
├── lib/
│   └── python3.11/
│       └── site-packages/  # ← Packages terinstal di sini
│           ├── pip/
│           ├── setuptools/
│           └── ...
├── pyvenv.cfg          # Konfigurasi venv
└── share/              # Shared data

# Struktur folder venv (Windows):
.venv/
├── Scripts/
│   ├── activate.bat
│   ├── activate.ps1
│   ├── python.exe
│   └── pip.exe
├── Lib/
│   └── site-packages/
├── Include/
├── pyvenv.cfg
└── tcl/

# Isi pyvenv.cfg:
# home = /usr/bin
# include-system-site-packages = false
# version = 3.11.4
# executable = /usr/bin/python3.11
# command = /usr/bin/python3 -m venv /home/user/project/.venv

# ===== Instalasi packages =====

# Instal package terbaru
pip install requests

# Instal versi spesifik
pip install requests==2.31.0

# Instal dengan batasan versi
pip install "requests>=2.28,<3.0"
pip install "django~=4.2"      # Compatible release (>=4.2, ==4.*)
pip install "flask>=3.0"       # Minimum version

# Instal dari git
pip install git+https://github.com/user/repo.git
pip install git+https://github.com/user/repo.git@branch-name
pip install git+https://github.com/user/repo.git@v1.0.0

# Instal dari local directory
pip install ./my-package/
pip install -e ./my-package/   # Editable mode (development)

# Instal beberapa packages sekaligus
pip install requests flask sqlalchemy

# ===== Upgrade dan Uninstall =====

# Upgrade package
pip install --upgrade requests
pip install -U requests

# Upgrade pip itu sendiri
pip install --upgrade pip

# Uninstall
pip uninstall requests

# ===== List dan Info =====

# List semua package terinstal
pip list

# List dengan format columns
pip list --format=columns

# List outdated packages
pip list --outdated

# Info tentang package
pip show requests

# ===== Requirements File =====

# Generate requirements.txt dari environment saat ini
pip freeze > requirements.txt

# Instal dari requirements.txt
pip install -r requirements.txt

# Instal dari requirements.txt dengan upgrade
pip install -r requirements.txt --upgrade

# ===== Cache =====

# Lihat cache
pip cache info

# Hapus cache
pip cache purge

# requirements.txt — Production (pinned versions)
# Untuk reproducible builds

# Web framework
django==4.2.13
djangorestframework==3.15.2

# Database
psycopg2-binary==2.9.9
sqlalchemy==2.0.31

# HTTP
requests==2.32.3
httpx==0.27.0

# Task queue
celery==5.4.0
redis==5.0.7

# Testing
pytest==8.2.2
pytest-django==4.8.0
pytest-cov==5.0.0

# Development
ruff==0.5.0
mypy==1.10.0
ipython==8.25.0

# requirements.in — Base requirements (unpinned)
# Digunakan dengan pip-tools untuk generate pinned requirements.txt

django>=4.2,<5.0
djangorestframework>=3.15
psycopg2-binary>=2.9
sqlalchemy>=2.0
requests>=2.28
httpx>=0.27
celery>=5.4
redis>=5.0

# Dev dependencies (opsional, pisahkan ke requirements-dev.in)
pytest
pytest-django
ruff
mypy

# Pisahkan dependency berdasarkan environment:

# requirements-base.txt    — shared dependencies
# requirements.txt         — production (includes base)
# requirements-dev.txt     — development (includes base + testing tools)
# requirements-test.txt    — testing only

# Contoh requirements-dev.txt:
# -r requirements.txt
pytest>=8.0
pytest-cov>=5.0
ruff>=0.5
mypy>=1.10
ipython>=8.0
debugpy>=1.8

# Menggunakan constraint file
# constraints.txt: membatasi versi tanpa menginstall
# django==4.2.13
# sqlalchemy==2.0.31

pip install -r requirements.txt -c constraints.txt

# Instal requirements-dev
pip install -r requirements-dev.txt

# ===== Instalasi pip-tools =====
pip install pip-tools

# ===== Workflow pip-tools =====

# 1. Buat requirements.in (input — apa yang kamu butuhkan)
# requirements.in:
# django>=4.2
# requests>=2.28
# sqlalchemy>=2.0

# 2. Compile ke requirements.txt (output — resolved, pinned)
pip-compile requirements.in
# Menghasilkan requirements.txt dengan versi exact + hash
# django==4.2.13 (via django>=4.2)
# requests==2.32.3 (via requests>=2.28)
# sqlalchemy==2.0.31 (via sqlalchemy>=2.0)
# ... beserta semua transitive dependencies

# 3. Sync environment dengan requirements.txt
pip-sync requirements.txt
# Menginstall yang kurang, menghapus yang tidak perlu

# ===== Advanced pip-tools =====

# Compile dengan upgrade semua
pip-compile --upgrade requirements.in

# Compile dengan upgrade package tertentu
pip-compile --upgrade-package django requirements.in

# Output ke file berbeda
pip-compile requirements.in -o requirements.txt

# Dev dependencies
pip-compile requirements-dev.in -o requirements-dev.txt

# Generate dengan hashes (untuk security)
pip-compile --generate-hashes requirements.in

# Sync dari multiple requirements files
pip-sync requirements.txt requirements-dev.txt

# ===== pip-tools Configuration (pyproject.toml) =====
# [tool.pip-tools]
# generate-hashes = true
# allow-unsafe = false
# strip-extras = true

# ===== Instalasi Poetry =====

# Linux / macOS / WSL
curl -sSL https://install.python-poetry.org | python3 -

# Windows (PowerShell)
(Invoke-WebRequest -Uri https://install.python-poetry.org -UseBasicParsing).Content | python -

# Atau via pip (kurang recommended)
pip install poetry

# Verifikasi
poetry --version

# ===== Konfigurasi =====
# Membuat venv di dalam project folder (recommended)
poetry config virtualenvs.in-project true

# Lihat semua konfigurasi
poetry config --list

# ===== Membuat Project Baru =====
poetry new my-project
# Menghasilkan:
# my-project/
# ├── pyproject.toml
# ├── README.md
# ├── my_project/
# │   └── __init__.py
# └── tests/
#     └── __init__.py

# Inisialisasi di project yang sudah ada
cd existing-project
poetry init

# ===== Menambah dependencies =====

# Add production dependency
poetry add requests
poetry add "django>=4.2,<5.0"
poetry add sqlalchemy@^2.0

# Add dev dependency
poetry add --group dev pytest ruff mypy
poetry add -G dev pytest

# Add optional dependency
poetry add --group optional redis

# ===== Menghapus dependencies =====
poetry remove requests
poetry remove --group dev pytest

# ===== Install semua dependencies =====
poetry install

# Install tanpa dev dependencies
poetry install --only main

# Install hanya dev
poetry install --only dev

# ===== Update dependencies =====
# Update semua
poetry update

# Update package tertentu
poetry update requests

# ===== Lock file =====
# poetry.lock otomatis dibuat/diupdate
# SELALU commit poetry.lock ke git!

# Re-resolve semua dependencies
poetry lock

# Lock tanpa update
poetry lock --no-update

# ===== List dependencies =====
poetry show
poetry show --tree        # Dengan dependency tree
poetry show --outdated    # Package yang bisa diupdate

# ===== Export ke requirements.txt =====
poetry export -f requirements.txt --output requirements.txt
poetry export -f requirements.txt --without-hashes -o requirements.txt

[tool.poetry]
name = "my-awesome-project"
version = "1.0.0"
description = "Deskripsi project kamu"
authors = ["Budi Santoso <budi@email.com>"]
license = "MIT"
readme = "README.md"
repository = "https://github.com/user/my-project"
keywords = ["python", "tutorial"]
packages = [{include = "my_project"}]

[tool.poetry.dependencies]
python = "^3.11"
django = "^4.2"
djangorestframework = "^3.15"
requests = "^2.31"
sqlalchemy = "^2.0"
celery = {version = "^5.4", extras = ["redis"]}
redis = "^5.0"
gunicorn = {version = "^22.0", optional = true}

[tool.poetry.group.dev.dependencies]
pytest = "^8.2"
pytest-cov = "^5.0"
pytest-django = "^4.8"
ruff = "^0.5"
mypy = "^1.10"
ipython = "^8.25"

[tool.poetry.group.docs.dependencies]
sphinx = "^7.3"
sphinx-rtd-theme = "^2.0"

[tool.poetry.scripts]
myproject = "my_project.cli:main"

[tool.poetry.plugins."my_project.plugins"]
myplugin = "my_project.plugins:MyPlugin"

[build-system]
requires = ["poetry-core"]
build-backend = "poetry.core.masonry.api"

# ===== Virtual Environment =====
poetry env info              # Info tentang venv
poetry env list              # List semua venv
poetry env use python3.11    # Ganti Python version
poetry env remove .venv      # Hapus venv

# ===== Running =====
poetry run python script.py  # Jalankan script di venv
poetry run pytest            # Jalankan pytest di venv
poetry run python -m mymodule

# Shell di dalam venv
poetry shell
# Sekarang semua command berjalan di venv
exit  # Keluar dari shell

# ===== Building dan Publishing =====
# Build package
poetry build
# Menghasilkan dist/my_project-1.0.0.tar.gz dan .whl

# Publish ke PyPI
poetry publish

# Build + Publish
poetry publish --build

# Publish ke private repository
poetry config repositories.private https://private.pypi.org/simple/
poetry publish -r private

# ===== Check dan Versioning =====
poetry check                  # Validasi pyproject.toml
poetry version                # Lihat versi
poetry version patch          # 1.0.0 → 1.0.1
poetry version minor          # 1.0.0 → 1.1.0
poetry version major          # 1.0.0 → 2.0.0

# ===== Instalasi Miniconda (recommended, lebih ringan dari Anaconda) =====

# Linux
wget https://repo.anaconda.com/miniconda/Miniconda3-latest-Linux-x86_64.sh
bash Miniconda3-latest-Linux-x86_64.sh

# macOS
wget https://repo.anaconda.com/miniconda/Miniconda3-latest-MacOSX-arm64.sh
bash Miniconda3-latest-MacOSX-arm64.sh

# Windows: Download installer dari https://docs.conda.io/en/latest/miniconda.html

# Verifikasi
conda --version
conda info

# ===== Konfigurasi =====
# Auto-activate base environment (optional)
conda config --set auto_activate_base false

# Tambah channel
conda config --add channels conda-forge
conda config --set channel_priority strict

# ===== Membuat Environment =====

# Buat env dengan Python versi spesifik
conda create -n myproject python=3.11

# Buat env dengan beberapa packages
conda create -n datascience python=3.11 numpy pandas scikit-learn jupyter

# Buat env dari file
conda env create -f environment.yml

# Buat env di folder spesifik
conda create --prefix ./envs python=3.11

# ===== Mengaktifkan / Deactivate =====
conda activate myproject
conda deactivate

# ===== List Environments =====
conda env list
# atau
conda info --envs

# ===== Install / Update / Remove Packages =====
# Install
conda install numpy pandas matplotlib
conda install -c conda-forge scikit-learn
conda install "numpy>=1.24,<2.0"

# Update
conda update numpy
conda update --all

# Remove
conda remove numpy

# ===== Export / Import Environment =====
# Export ke YAML
conda env export > environment.yml
conda env export --no-builds > environment.yml  # Tanpa build numbers

# Export hanya packages yang diinstall secara eksplisit
conda env export --from-history > environment.yml

# Import dari YAML
conda env create -f environment.yml

# Update existing env dari YAML
conda env update -f environment.yml --prune

# ===== YAML File =====
# environment.yml:
# name: myproject
# channels:
#   - conda-forge
#   - defaults
# dependencies:
#   - python=3.11
#   - numpy>=1.24
#   - pandas>=2.0
#   - scikit-learn>=1.3
#   - pip:
#     - some-pip-package>=1.0

# ===== Instalasi uv =====
# Linux / macOS
curl -LsSf https://astral.sh/uv/install.sh | sh

# Windows (PowerShell)
powershell -c "irm https://astral.sh/uv/install.ps1 | iex"

# Atau via pip
pip install uv

# Verifikasi
uv --version

# ===== Virtual Environment =====
# Buat venv dengan uv (sangat cepat!)
uv venv
uv venv --python 3.11
uv venv .venv --python 3.12

# ===== Install Packages =====
# Install packages (10-100x lebih cepat dari pip!)
uv pip install requests
uv pip install "django>=4.2" sqlalchemy

# Install dari requirements.txt
uv pip install -r requirements.txt

# Compile requirements
uv pip compile requirements.in -o requirements.txt

# Sync environment
uv pip sync requirements.txt

# ===== uv sebagai Python Manager =====
# Install Python versions
uv python install 3.11 3.12 3.13
uv python list

# ===== uv Project Management (v0.4+) =====
# Inisialisasi project
uv init my-project
cd my-project

# Tambah dependency
uv add requests
uv add "django>=4.2"
uv add --dev pytest ruff

# Remove dependency
uv remove requests

# Run command
uv run python script.py
uv run pytest

# Lock dependencies
uv lock

# Sync environment
uv sync

# ===== Benchmark =====
# pip install (dengan cache): ~10 detik
# uv pip install (dengan cache): ~0.3 detik
# Perbedaan sangat signifikan untuk CI/CD!

# pyproject.toml — Standalone (tanpa Poetry)
[project]
name = "my-project"
version = "1.0.0"
description = "Deskripsi project"
readme = "README.md"
license = {text = "MIT"}
requires-python = ">=3.11"
authors = [
    {name = "Budi Santoso", email = "budi@email.com"},
]
keywords = ["python", "web", "api"]
classifiers = [
    "Development Status :: 4 - Beta",
    "Programming Language :: Python :: 3",
    "Programming Language :: Python :: 3.11",
    "Programming Language :: Python :: 3.12",
]

# Dependencies
dependencies = [
    "django>=4.2,<5.0",
    "djangorestframework>=3.15",
    "requests>=2.28",
    "sqlalchemy>=2.0",
]

# Optional dependencies
[project.optional-dependencies]
dev = [
    "pytest>=8.0",
    "pytest-cov>=5.0",
    "ruff>=0.5",
    "mypy>=1.10",
]
docs = [
    "sphinx>=7.3",
    "sphinx-rtd-theme>=2.0",
]
all = [
    "my-project[dev,docs]",
]

# Entry points / CLI
[project.scripts]
myproject = "my_project.cli:main"

# URLs
[project.urls]
Homepage = "https://github.com/user/my-project"
Documentation = "https://my-project.readthedocs.io"
Repository = "https://github.com/user/my-project"
Issues = "https://github.com/user/my-project/issues"

# ===== Build System =====
[build-system]
requires = ["setuptools>=68.0", "wheel"]
build-backend = "setuptools.backends._legacy:_Backend"

# ===== Tool Configurations =====

# Ruff (linter + formatter)
[tool.ruff]
target-version = "py311"
line-length = 100

[tool.ruff.lint]
select = ["E", "F", "I", "N", "W", "UP", "B", "A", "SIM"]

# Pytest
[tool.pytest.ini_options]
testpaths = ["tests"]
python_files = "test_*.py"
addopts = "-v --tb=short --cov=my_project"

# MyPy
[tool.mypy]
python_version = "3.11"
strict = true
warn_return_any = true
warn_unused_configs = true

# Coverage
[tool.coverage.run]
source = ["my_project"]
omit = ["tests/*"]

[tool.coverage.report]
exclude_lines = [
    "pragma: no cover",
    "if TYPE_CHECKING:",
    "if __name__ == .__main__.",
]

# ===== Setup Awal Project =====
mkdir my-project && cd my-project
git init

# Buat virtual environment
python3 -m venv .venv
source .venv/bin/activate   # Linux/Mac
# .venv\Scripts\activate    # Windows

# Buat file standar
touch README.md
echo ".venv/" >> .gitignore
echo "__pycache__/" >> .gitignore
echo "*.pyc" >> .gitignore

# Install dependencies
pip install django pytest ruff
pip freeze > requirements.txt

# ===== Daily Development =====
# Aktivasi (setiap buka terminal baru)
source .venv/bin/activate

# Install package baru
pip install new-package
pip freeze > requirements.txt  # Update requirements!
git add requirements.txt
git commit -m "Add new-package dependency"

# ===== Join Project yang Sudah Ada =====
git clone https://github.com/user/project.git
cd project
python3 -m venv .venv
source .venv/bin/activate
pip install -r requirements.txt

# ===== Deployment Preparation =====
pip install -r requirements.txt
python manage.py test          # Jalankan test
ruff check .                   # Lint check
python manage.py collectstatic # Django specific

# ===== Setup Awal =====
poetry new my-project
cd my-project
git init

# Tambah dependencies
poetry add django requests sqlalchemy
poetry add --group dev pytest ruff mypy

# ===== Daily Development =====
# Tidak perlu aktivasi manual — poetry handle semuanya!
poetry run python manage.py runserver
poetry run pytest
poetry run ruff check .

# Atau masuk ke shell
poetry shell
python manage.py runserver
pytest
exit

# Tambah dependency baru
poetry add httpx
# Poetry otomatis update pyproject.toml dan poetry.lock!

# Commit ke git
git add pyproject.toml poetry.lock
git commit -m "Add httpx dependency"

# ===== Join Project =====
git clone https://github.com/user/project.git
cd project
poetry install
# Poetry baca pyproject.toml + poetry.lock, install semua!

# ===== Update Dependencies =====
poetry update              # Update semua
poetry update requests     # Update satu package
poetry show --outdated     # Cek yang bisa diupdate

# ===== Dockerfile dengan venv =====
FROM python:3.11-slim

WORKDIR /app

# Buat virtual environment
RUN python -m venv /opt/venv
ENV PATH="/opt/venv/bin:$PATH"

# Install dependencies
COPY requirements.txt .
RUN pip install --no-cache-dir -r requirements.txt

# Copy application
COPY . .

# Run
CMD ["python", "app.py"]

# ===== Dockerfile dengan Poetry =====
FROM python:3.11-slim

WORKDIR /app

# Install Poetry
RUN pip install poetry && \
    poetry config virtualenvs.in-project true

# Copy dependency files
COPY pyproject.toml poetry.lock ./

# Install dependencies (tanpa dev)
RUN poetry install --only main --no-interaction

# Copy application
COPY . .

# Activate venv
ENV PATH="/app/.venv/bin:$PATH"

CMD ["python", "app.py"]

# ===== Multi-stage build (lebih kecil) =====
FROM python:3.11-slim AS builder

WORKDIR /app
RUN python -m venv /opt/venv
ENV PATH="/opt/venv/bin:$PATH"

COPY requirements.txt .
RUN pip install --no-cache-dir -r requirements.txt

FROM python:3.11-slim AS runtime

WORKDIR /app
COPY --from=builder /opt/venv /opt/venv
ENV PATH="/opt/venv/bin:$PATH"

COPY . .
CMD ["python", "app.py"]

# ===== docker-compose.yml =====
# version: "3.8"
# services:
#   app:
#     build: .
#     volumes:
#       - .:/app
#     ports:
#       - "8000:8000"
#     environment:
#       - DATABASE_URL=postgresql://user:pass@db:5432/mydb
#   db:
#     image: postgres:15
#     environment:
#       - POSTGRES_PASSWORD=pass

# .gitignore — Python project

# Virtual environments
.venv/
venv/
env/
ENV/

# Python
__pycache__/
*.py[cod]
*$py.class
*.so
*.egg-info/
dist/
build/
*.egg

# IDE
.vscode/
.idea/
*.swp
*.swo

# OS
.DS_Store
Thumbs.db

# Environment variables
.env
.env.local

# Coverage
.coverage
htmlcov/

# Mypy
.mypy_cache/

# Ruff
.ruff_cache/

# Pytest
.pytest_cache/

# Jupyter
.ipynb_checkpoints/

# ===== Decision Tree =====
#
# Kamu membuat apa?
# │
# ├── 📚 Library yang akan di-publish ke PyPI?
# │   └── → Poetry atau Hatchling
# │
# ├── 🌐 Web application / API?
# │   └── → venv + pip-tools (atau Poetry)
# │
# ├── 📊 Data Science / Machine Learning?
# │   └── → Conda (atau mamba)
# │
# ├── 🤖 Script / Automation?
# │   └── → venv + pip (simplest)
# │
# ├── ⚡ Performance-critical CI/CD?
# │   └── → uv (sangat cepat)
# │
# └── 🏢 Enterprise / Tim besar?
#     └── → Poetry (atau PDM) + Docker
#
# ===== Quick Reference =====
#
# Tool       │ Buat Venv │ Install │ Lock │ Build │ Publish
# ───────────┼───────────┼─────────┼──────┼───────┼────────
# venv+pip   │ ✅        │ ✅      │ ❌    │ ❌     │ ❌
# pip-tools  │ ❌        │ ✅      │ ✅    │ ❌     │ ❌
# Poetry     │ ✅        │ ✅      │ ✅    │ ✅     │ ✅
# Conda      │ ✅        │ ✅      │ ❌    │ ❌     │ ❌
# uv         │ ✅        │ ✅      │ ✅    │ ✅     │ ❌
# PDM        │ ✅        │ ✅      │ ✅    │ ✅     │ ✅