Add a script that installs examples (#171)

* Add install_examples.py

* install_examples.py: Run Black

* install_examples.py: Fix lint error

* install_examples.py: Implement Matthew's feedback on _deactivate_venv()

Author: bkeryan

scripts/install_examples.py

@@ -0,0 +1,68 @@
+#!/usr/bin/env python3
+"""Install all example services."""
+
+import os
+import pathlib
+import shutil
+import subprocess
+
+EXAMPLES_PATH = pathlib.Path(__file__).parent.parent / "examples"
+SERVICES_PATH = (
+    pathlib.Path(os.environ["ProgramData"])
+    / "National Instruments"
+    / "MeasurementLink"
+    / "Services"
+)
+
+
+def main():
+    """Install all example services."""
+    clean_env = _get_clean_env()
+    for example_path in EXAMPLES_PATH.iterdir():
+        if not (example_path / "pyproject.toml").exists():
+            continue
+
+        print(f"{example_path.name}:")
+
+        poetry_lock = example_path / "poetry.lock"
+        if poetry_lock.exists():
+            print(f"Deleting lock file {poetry_lock}")
+            poetry_lock.unlink()
+
+        venv_dir = example_path / ".venv"
+        if venv_dir.is_dir():
+            print(f"Deleting virtualenv {venv_dir}")
+            shutil.rmtree(venv_dir)
+
+        print(f"Installing dependencies")
+        subprocess.run(["poetry", "-v", "install"], check=True, cwd=example_path, env=clean_env)
+
+        install_path = SERVICES_PATH / example_path.name
+        if install_path.is_dir():
+            print(f"Deleting example from {install_path}")
+            shutil.rmtree(install_path)
+
+        print(f"Installing example into {install_path}")
+        shutil.copytree(example_path, install_path)
+
+        print("")
+
+
+def _get_clean_env():
+    """Get a clean environment with no venv activated.
+
+    This is a workaround for https://github.com/python-poetry/poetry/issues/4055
+    Option to force Poetry to create a virtual environment, even if a virtual env is active
+
+    """
+    env = os.environ.copy()
+    if env.pop("VIRTUAL_ENV", None) is not None:
+        for var in os.environ.keys():
+            value = env.pop(f"_OLD_VIRTUAL_{var}", None)
+            if value is not None:
+                env[var] = value
+    return env
+
+
+if __name__ == "__main__":
+    main()