Add dry_run feature

_configuration/src/opentelemetry/configuration/_internal/__init__.py

@@ -26,6 +26,7 @@
 from jsonschema.validators import Draft202012Validator
 from referencing import Registry, Resource
 from yaml import safe_load
+from black import Mode, format_str
 
 from opentelemetry.configuration._internal.path_function import path_function
 
@@ -69,7 +70,6 @@ def validate_configuration(schema_path: Path, configuration: dict):
         raise Exception(f"{schema_path} does not exist")
 
     def retrieve_from_path(path: str):
-        set_trace()
         return Resource.from_contents(json_loads(Path(path).read_text()))
 
     Draft202012Validator(
@@ -279,14 +279,18 @@ def traverse(
 
 
 def create_object(
-    configuration: dict, processed_schema: dict, object_name: str
+    configuration: dict,
+    processed_schema: dict,
+    object_name: str,
+    dry_run=False
 ) -> object:
     def create_object(
         configuration: dict,
         processed_schema: dict,
         path_function: dict,
         original_processed_schema: dict,
         original_path_function: dict,
+        dry_run=False
     ) -> object:
 
         positional_arguments = []
@@ -355,18 +359,29 @@ def create_object(
             else:
                 optional_arguments[configuration_key] = object_
 
-        return path_function["function"](
+        result = path_function["function"](
             *positional_arguments, **optional_arguments
         )
-
-    return create_object(
+        if dry_run:
+            return result[1]
+        elif isinstance(result, tuple):
+            return result[0]
+        else:
+            return result
+
+    result = create_object(
         configuration[object_name],
         processed_schema[object_name],
         path_function[object_name],
         processed_schema,
         path_function,
+        dry_run=dry_run,
     )
 
+    if isinstance(result, str):
+        return format_str(result, mode=Mode(line_length=1))
+    return result
+
 
 def substitute_environment_variables(
     configuration: dict, processed_schema: dict

_configuration/src/opentelemetry/configuration/_internal/path_function.py

@@ -22,7 +22,7 @@
     OTLPSpanExporter as HTTPOTLPSpanExporter,
 )
 from opentelemetry.exporter.zipkin.proto.http import ZipkinExporter
-from opentelemetry.sdk.resources import Resource
+from opentelemetry.sdk.resources import Resource  # noqa
 from opentelemetry.sdk.trace import (
     SpanLimits,
     SynchronousMultiSpanProcessor,
@@ -38,6 +38,9 @@
     ALWAYS_ON,
     ParentBasedTraceIdRatio,
 )
+from ipdb import set_trace
+
+set_trace
 
 _resource = None
 
@@ -634,11 +637,19 @@ def tracer_provider_sampler_trace_id_ratio_based(ratio: float = None):
 
 
 def resource(attributes: object = None, schema_url: str = None):
-    return Resource.create(attributes=attributes, schema_url=schema_url)
+    command = (
+        f'resource = Resource.create(attributes={attributes}, '
+        f'schema_url="{schema_url}")'
+    )
+    exec(command)
+    return locals()["resource"], command
 
 
 def resource_attributes(service_name: str = None, **kwargs):
-    return {"service.name": service_name, **kwargs}
+    command = str({"service.name": service_name, **kwargs})
+    command = f'resource_attributes = {command}'
+    exec(command)
+    return locals()["resource_attributes"], command
 
 
 path_function = {

_configuration/tests/test_configuration.py

@@ -32,6 +32,8 @@
 )
 from opentelemetry.configuration._internal.path_function import set_resource
 
+set_trace
+
 data_path = Path(__file__).parent.joinpath("data")
 
 
@@ -152,12 +154,34 @@ def test_subschemas():
     # dictionary the schema components of each plugin component sub schema then
     # use the resulting schema dictionary to do the validation.
 
-    set_trace()
-
     configuration = load_configuration(
         data_path.joinpath("configuration").joinpath("configuration_0.yaml")
     )
 
     # FIXME do the same for configuration components
 
     Draft202012Validator(resolved_schema).validate(configuration)
+
+
+def test_dry_run():
+
+    configuration = load_configuration(
+        data_path.joinpath("configuration").joinpath("configuration_0.yaml")
+    )
+
+    schema_path = data_path.joinpath("schema").joinpath(
+        "opentelemetry_configuration.json"
+    )
+
+    try:
+        validate_configuration(schema_path, configuration)
+    except Exception as error:
+        fail(f"Unexpected exception raised: {error}")
+
+    processed_schema = process_schema(resolve_schema(schema_path))
+
+    result = create_object(
+        configuration, processed_schema, "resource", dry_run=True
+    )
+    print()
+    print(result)