add test

ddtrace/__init__.py

@@ -6,12 +6,9 @@
 LOADED_MODULES = frozenset(sys.modules.keys())
 
 # Configuration for the whole tracer from file. Do it before anything else happens.
-from ddtrace.internal.native import PyConfigurator
+from ddtrace.internal.native import get_configuration_from_disk
 
-configurator = PyConfigurator(debug_logs=False)
-configurator.set_envp(["%s=%s" % (k, v) for k, v in os.environ.items()])
-configurator.set_args(sys.argv)
-for key, value in configurator.get_configuration().items():
+for key, value in get_configuration_from_disk().items():
     os.environ[key] = str(value).lower()
 
 from ddtrace.internal.module import ModuleWatchdog

ddtrace/internal/native/__init__.py

@@ -1,2 +1,24 @@
+import os
+import sys
+from typing import Dict
+
 from ._native import DDSketch  # noqa: F401
-from ._native import PyConfigurator  # noqa: F401
+from ._native import PyConfigurator
+
+
+def get_configuration_from_disk(debug_logs: bool = False, file_override="") -> Dict[str, str]:
+    # type: (bool, str) -> Dict[str, str]
+    """
+    Retrieves the tracer configuration from disk. Calls the PyConfigurator object
+    to read the configuration from the disk using the libdatadog shared library
+    and returns the corresponding configuration
+    """
+    configurator = PyConfigurator(debug_logs)
+    configurator.set_envp(["%s=%s" % (k, v) for k, v in os.environ.items()])
+    configurator.set_args(sys.argv)
+
+    # Set the file override if provided. Only used for testing purposes.
+    if file_override:
+        configurator.set_file_override(file_override)
+
+    return configurator.get_configuration()

ddtrace/internal/native/_native.pyi

@@ -1,4 +1,4 @@
-from typing import List
+from typing import List, Dict
 
 class DDSketch:
     def __init__(self): ...
@@ -11,4 +11,5 @@ class PyConfigurator:
     def __init__(self, debug_logs: bool): ...
     def set_envp(self, envp: List[str]) -> None: ...
     def set_args(self, args: List[str]) -> None: ...
-    def get_configuration(self) -> dict: ...
+    def set_file_override(self, file: str) -> None: ...
+    def get_configuration(self) -> Dict[str, str]: ...

setup.py

@@ -666,7 +666,6 @@ def get_exts_for(name):
             py_limited_api="auto",
             binding=Binding.PyO3,
             debug=os.getenv("_DD_RUSTC_DEBUG") == "1",
-            strip=Strip.No if os.getenv("_DD_RUSTC_DEBUG") == "1" else Strip.All,
         ),
     ],
 )

src/native/Cargo.toml

@@ -4,9 +4,9 @@ version = "0.1.0"
 edition = "2021"
 
 [profile.release]
-lto = true
+lto = "fat" # lto = true breaks with libdatadog 15.0.0, so we use the next best thing
 strip = "debuginfo"
-opt-level = 3
+opt-level = 3 # Optimize for performance
 
 [dependencies]
 pyo3 = { version = "0.22.3", features = ["extension-module"] }

src/native/library_config.rs

@@ -6,6 +6,7 @@ use pyo3::types::PyDict;
 #[pyclass(name = "PyConfigurator", module = "ddtrace.internal._native")]
 pub struct PyConfigurator {
     configurator: Box<Configurator>,
+    file: String,
     envp: Vec<String>,
     args: Vec<String>,
 }
@@ -16,6 +17,7 @@ impl PyConfigurator {
     pub fn new(debug_logs: bool) -> Self {
         PyConfigurator {
             configurator: Box::new(Configurator::new(debug_logs)),
+            file: "/etc/datadog-agent/managed/datadog-apm-libraries/stable/libraries_config.yaml".to_string(), // TODO: Use const from libdatadog (PR pending)
             envp: Vec::new(),
             args: Vec::new(),
         }
@@ -30,6 +32,11 @@ impl PyConfigurator {
         self.args = args;
         Ok(())
     }
+
+    pub fn set_file_override(&mut self, file: String) -> PyResult<()> {
+        self.file = file;
+        Ok(())
+    }
 
     pub fn get_configuration(&self, py: Python<'_>) -> PyResult<PyObject> {
         let envp: Vec<&[u8]> = self.envp.iter().map(|s| s.as_bytes()).collect();
@@ -42,8 +49,7 @@ impl PyConfigurator {
         };
 
         let res_config = self.configurator.get_config_from_file(
-            "/etc/datadog-agent/managed/datadog-apm-libraries/stable/libraries_config.yaml"
-                .as_ref(),
+            self.file.as_ref(),
             process_info,
         );
         match res_config {

tests/internal/test_native.py

@@ -0,0 +1,34 @@
+from ddtrace.internal.native import get_configuration_from_disk
+
+def test_get_configuration_from_disk(tmp_path):
+    # First test -- config matches & should be returned
+    config_1 = tmp_path / "config_1.yaml"
+    config_1.write_text("""
+rules:
+  - selectors:
+    - origin: language
+      matches:
+        - python
+      operator: equals
+    configuration:
+      DD_SERVICE: my-service
+""", encoding="utf-8")
+
+    config = get_configuration_from_disk(file_override=str(config_1))
+    assert config == {"DD_SERVICE": "my-service"}
+
+    # Second test -- config does not match & should not be returned
+    config_2 = tmp_path / "config_2.yaml"
+    config_2.write_text("""
+rules:
+  - selectors:
+    - origin: language
+      matches:
+        - nodejs
+      operator: equals
+    configuration:
+      DD_SERVICE: my-service
+""", encoding="utf-8")
+
+    config = get_configuration_from_disk(file_override=str(config_2))
+    assert config == {}

tests/suitespec.yml

@@ -62,6 +62,7 @@ components:
     - ddtrace/internal/logger.py
     - ddtrace/internal/metrics.py
     - ddtrace/internal/module.py
+    - ddtrace/internal/native/*
     - ddtrace/internal/packages.py
     - ddtrace/internal/third-party.tar.gz
     - ddtrace/internal/periodic.py