Extract requirements (#12051)

homeassistant/requirements.py

@@ -0,0 +1,45 @@
+"""Module to handle installing requirements."""
+import asyncio
+from functools import partial
+import logging
+import os
+
+import homeassistant.util.package as pkg_util
+
+DATA_PIP_LOCK = 'pip_lock'
+CONSTRAINT_FILE = 'package_constraints.txt'
+_LOGGER = logging.getLogger(__name__)
+
+
+@asyncio.coroutine
+def async_process_requirements(hass, name, requirements):
+    """Install the requirements for a component or platform.
+
+    This method is a coroutine.
+    """
+    pip_lock = hass.data.get(DATA_PIP_LOCK)
+    if pip_lock is None:
+        pip_lock = hass.data[DATA_PIP_LOCK] = asyncio.Lock(loop=hass.loop)
+
+    pip_install = partial(pkg_util.install_package,
+                          **pip_kwargs(hass.config.config_dir))
+
+    with (yield from pip_lock):
+        for req in requirements:
+            ret = yield from hass.async_add_job(pip_install, req)
+            if not ret:
+                _LOGGER.error("Not initializing %s because could not install "
+                              "requirement %s", name, req)
+                return False
+
+    return True
+
+
+def pip_kwargs(config_dir):
+    """Return keyword arguments for PIP install."""
+    kwargs = {
+        'constraints': os.path.join(os.path.dirname(__file__), CONSTRAINT_FILE)
+    }
+    if not pkg_util.running_under_virtualenv():
+        kwargs['target'] = os.path.join(config_dir, 'deps')
+    return kwargs