Add services.yaml validator (#23205)

* Add services.yaml validator

* Fix path

script/hassfest/services.py

@@ -0,0 +1,104 @@
+"""Validate dependencies."""
+import pathlib
+from typing import Dict
+
+import re
+import voluptuous as vol
+from voluptuous.humanize import humanize_error
+
+from homeassistant.exceptions import HomeAssistantError
+from homeassistant.helpers import config_validation as cv
+from homeassistant.util.yaml import load_yaml
+
+from .model import Integration
+
+
+def exists(value):
+    """Check if value exists."""
+    if value is None:
+        raise vol.Invalid("Value cannot be None")
+    return value
+
+
+FIELD_SCHEMA = vol.Schema({
+    vol.Required('description'): str,
+    vol.Optional('example'): exists,
+    vol.Optional('default'): exists,
+    vol.Optional('values'): exists,
+    vol.Optional('required'): bool,
+})
+
+SERVICE_SCHEMA = vol.Schema({
+    vol.Required('description'): str,
+    vol.Optional('fields'): vol.Schema({
+        str: FIELD_SCHEMA
+    })
+})
+
+SERVICES_SCHEMA = vol.Schema({
+    cv.slug: SERVICE_SCHEMA
+})
+
+
+def grep_dir(path: pathlib.Path, glob_pattern: str, search_pattern: str) \
+        -> bool:
+    """Recursively go through a dir and it's children and find the regex."""
+    pattern = re.compile(search_pattern)
+
+    for fil in path.glob(glob_pattern):
+        if not fil.is_file():
+            continue
+
+        if pattern.search(fil.read_text()):
+            return True
+
+    return False
+
+
+def validate_services(integration: Integration):
+    """Validate services."""
+    # Find if integration uses services
+    has_services = grep_dir(integration.path, "**/*.py",
+                            r"hass\.(services|async_register)")
+
+    if not has_services:
+        return
+
+    try:
+        data = load_yaml(str(integration.path / 'services.yaml'))
+    except FileNotFoundError:
+        print(
+            "Warning: {} registeres services but has no services.yaml".format(
+                integration.domain))
+        # integration.add_error(
+        #     'services', 'Registers services but has no services.yaml')
+        return
+    except HomeAssistantError:
+        integration.add_error(
+            'services', 'Registers services but unable to load services.yaml')
+        return
+
+    try:
+        SERVICES_SCHEMA(data)
+    except vol.Invalid as err:
+        integration.add_error(
+            'services',
+            "Invalid services.yaml: {}".format(humanize_error(data, err)))
+
+
+def validate(integrations: Dict[str, Integration], config):
+    """Handle dependencies for integrations."""
+    # check services.yaml is cool
+    for integration in integrations.values():
+        if not integration.manifest:
+            continue
+
+        validate_services(integration)
+
+        # check that all referenced dependencies exist
+        for dep in integration.manifest['dependencies']:
+            if dep not in integrations:
+                integration.add_error(
+                    'dependencies',
+                    "Dependency {} does not exist"
+                )