Fix the auto instrumentation command

docs/examples/auto-instrumentation/README.md

@@ -92,7 +92,7 @@ Span(name="serv_request", context=SpanContext(trace_id=0x9c0e0ce8f7b7dbb51d1d6e7
 Now, kill the execution of `server_instrumented.py` with `ctrl + c` and run this instead:
 
 ```sh
-$ opentelemetry-auto-instrumentation opentelemetry-python/opentelemetry-auto-instrumentation/example/server_uninstrumented.py
+$ opentelemetry-auto-instrumentation python docs/examples/auto-instrumentation/server_uninstrumented.py
 ```
 
 In the console where you previously executed `client.py`, run again this again:

opentelemetry-auto-instrumentation/src/opentelemetry/auto_instrumentation/__init__.py

@@ -20,9 +20,9 @@
 
 ::
 
-    opentelemetry-auto-instrumentation program.py
+    opentelemetry-auto-instrumentation python program.py
 
 The code in ``program.py`` needs to use one of the packages for which there is
-an OpenTelemetry extension. For a list of the available extensions please check
-`here <https://opentelemetry-python.readthedocs.io/>`_.
+an OpenTelemetry integration. For a list of the available integrations please
+check `here <https://opentelemetry-python.readthedocs.io/>`_.
 """

opentelemetry-auto-instrumentation/src/opentelemetry/auto_instrumentation/auto_instrumentation.py

@@ -15,22 +15,40 @@
 # limitations under the License.
 
 from logging import getLogger
-from runpy import run_path
+from os import environ, execl, getcwd
+from os.path import abspath, dirname, pathsep
+from shutil import which
 from sys import argv
 
-from pkg_resources import iter_entry_points
-
 logger = getLogger(__file__)
 
 
 def run() -> None:
 
-    for entry_point in iter_entry_points("opentelemetry_instrumentor"):
-        try:
-            entry_point.load()().instrument()  # type: ignore
-            logger.debug("Instrumented %s", entry_point.name)
+    python_path = environ.get("PYTHONPATH")
+
+    if not python_path:
+        python_path = []
+
+    else:
+        python_path = python_path.split(pathsep)
+
+    cwd_path = getcwd()
+
+    # This is being added to support applications that are being run from their
+    # own executable, like Django.
+    # FIXME investigate if there is another way to achieve this
+    if cwd_path not in python_path:
+        python_path.insert(0, cwd_path)
+
+    filedir_path = dirname(abspath(__file__))
+
+    python_path = [path for path in python_path if path != filedir_path]
+
+    python_path.insert(0, filedir_path)
+
+    environ["PYTHONPATH"] = pathsep.join(python_path)
 
-        except Exception:  # pylint: disable=broad-except
-            logger.exception("Instrumenting of %s failed", entry_point.name)
+    executable = which(argv[1])
 
-    run_path(argv[1], run_name="__main__")  # type: ignore
+    execl(executable, executable, *argv[2:])

opentelemetry-auto-instrumentation/src/opentelemetry/auto_instrumentation/sitecustomize.py

@@ -0,0 +1,28 @@
+# Copyright The OpenTelemetry Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from logging import getLogger
+
+from pkg_resources import iter_entry_points
+
+logger = getLogger(__file__)
+
+
+for entry_point in iter_entry_points("opentelemetry_instrumentor"):
+    try:
+        entry_point.load()().instrument()  # type: ignore
+        logger.debug("Instrumented %s", entry_point.name)
+
+    except Exception:  # pylint: disable=broad-except
+        logger.exception("Instrumenting of %s failed", entry_point.name)

opentelemetry-auto-instrumentation/tests/test_run.py

@@ -0,0 +1,106 @@
+# Copyright The OpenTelemetry Authors
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+# type: ignore
+
+from os import environ, getcwd
+from os.path import abspath, dirname, pathsep
+from unittest import TestCase
+from unittest.mock import patch
+
+from opentelemetry.auto_instrumentation import auto_instrumentation
+
+
+class TestRun(TestCase):
+    auto_instrumentation_path = dirname(abspath(auto_instrumentation.__file__))
+
+    @classmethod
+    def setUpClass(cls):
+        cls.argv_patcher = patch(
+            "opentelemetry.auto_instrumentation.auto_instrumentation.argv"
+        )
+        cls.execl_patcher = patch(
+            "opentelemetry.auto_instrumentation.auto_instrumentation.execl"
+        )
+        cls.which_patcher = patch(
+            "opentelemetry.auto_instrumentation.auto_instrumentation.which"
+        )
+
+        cls.argv_patcher.start()
+        cls.execl_patcher.start()
+        cls.which_patcher.start()
+
+    @classmethod
+    def tearDownClass(cls):
+        cls.argv_patcher.stop()
+        cls.execl_patcher.stop()
+        cls.which_patcher.stop()
+
+    @patch.dict("os.environ", {"PYTHONPATH": ""})
+    def test_empty(self):
+        auto_instrumentation.run()
+        self.assertEqual(
+            environ["PYTHONPATH"],
+            pathsep.join([self.auto_instrumentation_path, getcwd()]),
+        )
+
+    @patch.dict("os.environ", {"PYTHONPATH": "abc"})
+    def test_non_empty(self):
+        auto_instrumentation.run()
+        self.assertEqual(
+            environ["PYTHONPATH"],
+            pathsep.join([self.auto_instrumentation_path, getcwd(), "abc"]),
+        )
+
+    @patch.dict(
+        "os.environ",
+        {"PYTHONPATH": pathsep.join(["abc", auto_instrumentation_path])},
+    )
+    def test_after_path(self):
+        auto_instrumentation.run()
+        self.assertEqual(
+            environ["PYTHONPATH"],
+            pathsep.join([self.auto_instrumentation_path, getcwd(), "abc"]),
+        )
+
+    @patch.dict(
+        "os.environ",
+        {
+            "PYTHONPATH": pathsep.join(
+                [auto_instrumentation_path, "abc", auto_instrumentation_path]
+            )
+        },
+    )
+    def test_single_path(self):
+        auto_instrumentation.run()
+        self.assertEqual(
+            environ["PYTHONPATH"],
+            pathsep.join([self.auto_instrumentation_path, getcwd(), "abc"]),
+        )
+
+
+class TestExecl(TestCase):
+    @patch(
+        "opentelemetry.auto_instrumentation.auto_instrumentation.argv",
+        new=[1, 2, 3],
+    )
+    @patch("opentelemetry.auto_instrumentation.auto_instrumentation.which")
+    @patch("opentelemetry.auto_instrumentation.auto_instrumentation.execl")
+    def test_execl(
+        self, mock_execl, mock_which
+    ):  # pylint: disable=no-self-use
+        mock_which.configure_mock(**{"return_value": "python"})
+
+        auto_instrumentation.run()
+
+        mock_execl.assert_called_with("python", "python", 3)