Add runtime configuration validation

statsd/assets/configuration/spec.yaml

@@ -9,14 +9,12 @@ files:
       - template: instances
         options:
           - name: host
-            required: true
             description: Host to collect StatsD data from.
             value:
               example: localhost
               type: string
           - name: port
             description: Port to use to collect StatsD data.
-            required: true
             value:
               example: 8126
               type: integer

statsd/datadog_checks/statsd/config_models/__init__.py

@@ -0,0 +1,18 @@
+# (C) Datadog, Inc. 2021-present
+# All rights reserved
+# Licensed under a 3-clause BSD style license (see LICENSE)
+from .instance import InstanceConfig
+from .shared import SharedConfig
+
+
+class ConfigMixin:
+    _config_model_instance: InstanceConfig
+    _config_model_shared: SharedConfig
+
+    @property
+    def config(self) -> InstanceConfig:
+        return self._config_model_instance
+
+    @property
+    def shared_config(self) -> SharedConfig:
+        return self._config_model_shared

statsd/datadog_checks/statsd/config_models/defaults.py

@@ -0,0 +1,36 @@
+# (C) Datadog, Inc. 2021-present
+# All rights reserved
+# Licensed under a 3-clause BSD style license (see LICENSE)
+from datadog_checks.base.utils.models.fields import get_default_field_value
+
+
+def shared_service(field, value):
+    return get_default_field_value(field, value)
+
+
+def instance_empty_default_hostname(field, value):
+    return False
+
+
+def instance_host(field, value):
+    return 'localhost'
+
+
+def instance_min_collection_interval(field, value):
+    return 15
+
+
+def instance_port(field, value):
+    return 8126
+
+
+def instance_service(field, value):
+    return get_default_field_value(field, value)
+
+
+def instance_tags(field, value):
+    return get_default_field_value(field, value)
+
+
+def instance_timeout(field, value):
+    return 10

statsd/datadog_checks/statsd/config_models/instance.py

@@ -0,0 +1,48 @@
+# (C) Datadog, Inc. 2021-present
+# All rights reserved
+# Licensed under a 3-clause BSD style license (see LICENSE)
+from __future__ import annotations
+
+from typing import Optional, Sequence
+
+from pydantic import BaseModel, root_validator, validator
+
+from datadog_checks.base.utils.functions import identity
+from datadog_checks.base.utils.models import validation
+
+from . import defaults, validators
+
+
+class InstanceConfig(BaseModel):
+    class Config:
+        allow_mutation = False
+
+    empty_default_hostname: Optional[bool]
+    host: Optional[str]
+    min_collection_interval: Optional[float]
+    port: Optional[int]
+    service: Optional[str]
+    tags: Optional[Sequence[str]]
+    timeout: Optional[int]
+
+    @root_validator(pre=True)
+    def _initial_validation(cls, values):
+        return validation.core.initialize_config(getattr(validators, 'initialize_instance', identity)(values))
+
+    @validator('*', pre=True, always=True)
+    def _ensure_defaults(cls, v, field):
+        if v is not None or field.required:
+            return v
+
+        return getattr(defaults, f'instance_{field.name}')(field, v)
+
+    @validator('*')
+    def _run_validations(cls, v, field):
+        if not v:
+            return v
+
+        return getattr(validators, f'instance_{field.name}', identity)(v, field=field)
+
+    @root_validator(pre=False)
+    def _final_validation(cls, values):
+        return validation.core.finalize_config(getattr(validators, 'finalize_instance', identity)(values))

statsd/datadog_checks/statsd/config_models/shared.py

@@ -0,0 +1,42 @@
+# (C) Datadog, Inc. 2021-present
+# All rights reserved
+# Licensed under a 3-clause BSD style license (see LICENSE)
+from __future__ import annotations
+
+from typing import Optional
+
+from pydantic import BaseModel, root_validator, validator
+
+from datadog_checks.base.utils.functions import identity
+from datadog_checks.base.utils.models import validation
+
+from . import defaults, validators
+
+
+class SharedConfig(BaseModel):
+    class Config:
+        allow_mutation = False
+
+    service: Optional[str]
+
+    @root_validator(pre=True)
+    def _initial_validation(cls, values):
+        return validation.core.initialize_config(getattr(validators, 'initialize_shared', identity)(values))
+
+    @validator('*', pre=True, always=True)
+    def _ensure_defaults(cls, v, field):
+        if v is not None or field.required:
+            return v
+
+        return getattr(defaults, f'shared_{field.name}')(field, v)
+
+    @validator('*')
+    def _run_validations(cls, v, field):
+        if not v:
+            return v
+
+        return getattr(validators, f'shared_{field.name}', identity)(v, field=field)
+
+    @root_validator(pre=False)
+    def _final_validation(cls, values):
+        return validation.core.finalize_config(getattr(validators, 'finalize_shared', identity)(values))

statsd/datadog_checks/statsd/config_models/validators.py

@@ -0,0 +1,3 @@
+# (C) Datadog, Inc. 2021-present
+# All rights reserved
+# Licensed under a 3-clause BSD style license (see LICENSE)

statsd/datadog_checks/statsd/data/conf.yaml.example

@@ -13,15 +13,16 @@ init_config:
 #
 instances:
 
-    ## @param host - string - required
+  -
+    ## @param host - string - optional - default: localhost
     ## Host to collect StatsD data from.
     #
-  - host: localhost
+    # host: localhost
 
-    ## @param port - integer - required
+    ## @param port - integer - optional - default: 8126
     ## Port to use to collect StatsD data.
     #
-    port: 8126
+    # port: 8126
 
     ## @param timeout - integer - optional - default: 10
     ## Custom timeout for your check request.