diff --git a/.gitignore b/.gitignore
index 35013a4..eba8e8f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,5 @@
 client.py
+.coverage
+htmlcov
 __pycache__/
+.pytest_cache
diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 305ada7..dfe554a 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -23,4 +23,4 @@ lint:
   - source /var/venv/bin/activate
   - pip install -r requirements.txt
   - pip install -r requirements-dev.txt
-  - make --no-print-directory lint
+  - make --no-print-directory --quiet lint
diff --git a/Makefile b/Makefile
index c163908..75be1bc 100644
--- a/Makefile
+++ b/Makefile
@@ -7,14 +7,14 @@ help: # Print help on Makefile
 
 open_all: # Open all projects files
 	${EDITOR} ${VBIN}/activate
-	${EDITOR} .gitignore .gitlab-ci.yaml client* main.py Makefile pyproject.toml README.md requirements-dev.txt requirements.txt
+	${EDITOR} .gitignore .gitlab-ci.yaml client* main.py Makefile pyproject.toml README.md requirements-dev.txt requirements.txt tests_*
 	${EDITOR} .git/hooks/p*-commit
 
 pre_commit: # Run the pre-commit hook
 	.git/hooks/pre-commit
 
 clean: # Remove files not tracked in source control
-	rm -rf __pycache__
+	rm -rf .pytest_cache htmlcov __pycache__
 	find . -type f -name "*.orig" -delete
 	find . -type f -name "*.pyc" -delete
 	find . -type d -empty -delete
@@ -24,3 +24,9 @@ lint: # Lint code
 	${VBIN}/pflake8 --config=pyproject.toml && echo "✅ pflake8"  || echo "🚨 pflake8"
 	${VBIN}/pydocstyle && echo "✅ pydocstyle"  || echo "🚨 pydocstyle"
 	${VBIN}/pylint --rcfile=pyproject.toml *.py && echo "✅ pylint"  || echo "🚨 pylint"
+
+test: # Test code
+	${VBIN}/pytest tests_*.py
+
+test_pdb: # Test code and open debugger if fail
+	${VBIN}/pytest --pdb tests_*.py
diff --git a/README.md b/README.md
index 84a90d5..de226f4 100644
--- a/README.md
+++ b/README.md
@@ -61,4 +61,3 @@ python main.py -h
 Details in [`requirements.txt`](requirements.txt) & [`requirements-dev.txt`](requirements-dev.txt)
 
 - [`opensearch-py`](https://opensearch.org/docs/latest/clients/python/)
-- [`opensearch_dsl`](https://pypi.org/project/opensearch-dsl/)
diff --git a/pyproject.toml b/pyproject.toml
index 3fc10b8..0ea49a1 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -5,3 +5,6 @@ max-line-length = 90
 score = false
 disable = ["W0107", "W0102"]
 ignore = "client.sample.py"
+
+[tool.pytest.ini_options]
+addopts = "--doctest-modules --exitfirst --failed-first --cov-report=html --cov-report=term:skip-covered --cov=."
diff --git a/requirements-dev.txt b/requirements-dev.txt
index 7577837..6c6bf80 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -1,5 +1,9 @@
 black
+coverage
 flake8==4 # see: https://github.com/johnthagen/python-blueprint/issues/113
 pydocstyle
 pylint
 pyproject-flake8
+pytest
+pytest-cov
+toml
diff --git a/tests_main.py b/tests_main.py
new file mode 100644
index 0000000..1f6ddf0
--- /dev/null
+++ b/tests_main.py
@@ -0,0 +1,93 @@
+#!/usr/bin/env python3
+# coding: utf8
+
+"""test_main.
+
+Testing `main.py`
+
+Author: frederic zind 2022-09-24
+Licenses: GNU AGPL v3: http://www.gnu.org/licenses/
+"""
+import logging
+from pytest import raises
+
+import main
+
+
+# Faking options from argparse
+class FakeOptions:  # pylint: disable=too-few-public-methods
+    """Options object mock."""
+
+    debug = False
+    mapping = False
+
+    def __init__(self, options):
+        """Built loggers options."""
+        if "debug" in options:
+            self.debug = True
+        if "mapping" in options:
+            self.mapping = True
+
+
+# ###
+# Testing setup_logging()
+# ###
+def test_logging_debug():
+    """Logger level is DEBUG. Set up with --debug argument."""
+    options = FakeOptions(["debug"])
+    main.setup_logging(options)
+
+    assert isinstance((main.logger), logging.Logger)
+    assert main.logger.level == 10
+
+
+def test_logging_default():
+    """Logger level is INFO. Set up without arguments."""
+    options = FakeOptions([])
+    main.setup_logging(options)
+
+    assert isinstance((main.logger), logging.Logger)
+    assert main.logger.level == 20
+
+
+# ###
+# Testing parse_args()
+# ###
+def test_parse_args():
+    """Defaults arguments are here."""
+    cli_options = main.parse_args(["--debug", "--mapping"])
+    assert cli_options.debug
+    assert cli_options.mapping
+
+
+# ###
+# Testing get_map_props()
+# ###
+def test_get_map_props():
+    """This is an integration test.
+
+    It need credentials to guery LDP stream.
+    """
+    pass
+
+
+# ###
+# Testing main()
+# ###
+def test_main_whithout_option():
+    """Called without option."""
+    options = FakeOptions([])
+
+    with raises(RuntimeError):
+        main.main(options)
+
+
+def test_main_demo_whith_mapping():
+    """Called with mapping option.
+
+    `main()` just tranfers `get_map_props()` return: this test is not really useful
+    """
+    options = FakeOptions(["mapping"])
+    response = main.main(options)
+
+    assert isinstance(response, list)