diff --git a/swh/icinga_plugins/tests/test_deposit.py b/swh/icinga_plugins/tests/test_deposit.py
index de4327c..60658c4 100644
--- a/swh/icinga_plugins/tests/test_deposit.py
+++ b/swh/icinga_plugins/tests/test_deposit.py
@@ -1,467 +1,467 @@
 # Copyright (C) 2019  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
 import io
 import os
 import tarfile
 import time
 
 from click.testing import CliRunner
 import pytest
 
 from swh.icinga_plugins.cli import icinga_cli_group
 
 from .web_scenario import WebScenario
 
 BASE_URL = "http://swh-deposit.example.org/1"
 
 COMMON_OPTIONS = [
     "--server",
     BASE_URL,
     "--username",
     "test",
     "--password",
     "test",
     "--collection",
     "testcol",
 ]
 
 
 SAMPLE_METADATA = """
 <?xml version="1.0" encoding="utf-8"?>
 <entry xmlns="http://www.w3.org/2005/Atom"
 xmlns:codemeta="https://doi.org/10.5063/SCHEMA/CODEMETA-2.0">
   <title>Test Software</title>
   <client>swh</client>
   <external_identifier>test-software</external_identifier>
   <codemeta:author>
     <codemeta:name>No One</codemeta:name>
   </codemeta:author>
 </entry>
 """
 
 
 ENTRY_TEMPLATE = """
 <entry xmlns="http://www.w3.org/2005/Atom"
        xmlns:sword="http://purl.org/net/sword/"
        xmlns:dcterms="http://purl.org/dc/terms/">
     <deposit_id>42</deposit_id>
     <deposit_date>2019-12-19 18:11:00</deposit_date>
     <deposit_archive>foo.tar.gz</deposit_archive>
     <deposit_status>{status}</deposit_status>
 
     <sword:packaging>http://purl.org/net/sword/package/SimpleZip</sword:packaging>
 </entry>
 """
 
 
 STATUS_TEMPLATE = """
 <entry xmlns="http://www.w3.org/2005/Atom"
        xmlns:sword="http://purl.org/net/sword/"
        xmlns:dcterms="http://purl.org/dc/terms/">
     <deposit_id>42</deposit_id>
     <deposit_status>{status}</deposit_status>
     <deposit_status_detail>{status_detail}</deposit_status_detail>
 </entry>
 """
 
 
 @pytest.fixture(scope="session")
 def tmp_path(tmp_path_factory):
     return tmp_path_factory.mktemp(__name__)
 
 
 @pytest.fixture(scope="session")
 def sample_metadata(tmp_path):
     """Returns a sample metadata file's path
 
     """
     path = os.path.join(tmp_path, "metadata.xml")
 
     with open(path, "w") as fd:
         fd.write(SAMPLE_METADATA)
 
     return path
 
 
 @pytest.fixture(scope="session")
 def sample_archive(tmp_path):
     """Returns a sample archive's path
 
     """
     path = os.path.join(tmp_path, "archive.tar.gz")
 
     with tarfile.open(path, "w:gz") as tf:
         tf.addfile(tarfile.TarInfo("hello.py"), io.BytesIO(b'print("Hello world")'))
 
     return path
 
 
 def invoke(args, catch_exceptions=False):
     runner = CliRunner()
     result = runner.invoke(icinga_cli_group, args)
     if not catch_exceptions and result.exception:
         print(result.output)
         raise result.exception
     return result
 
 
 def test_deposit_immediate_success(
     requests_mock, mocker, sample_archive, sample_metadata, mocked_time
 ):
     scenario = WebScenario()
 
     scenario.add_step(
-        "post", BASE_URL + "/testcol/", ENTRY_TEMPLATE.format(status="done")
+        "post", f"{BASE_URL}/testcol/", ENTRY_TEMPLATE.format(status="done")
     )
 
     scenario.install_mock(requests_mock)
 
     result = invoke(
         [
             "check-deposit",
             *COMMON_OPTIONS,
             "single",
             "--archive",
             sample_archive,
             "--metadata",
             sample_metadata,
         ]
     )
 
     assert result.output == (
         "DEPOSIT OK - Deposit took 0.00s and succeeded.\n"
         "| 'load_time' = 0.00s\n"
         "| 'total_time' = 0.00s\n"
         "| 'upload_time' = 0.00s\n"
         "| 'validation_time' = 0.00s\n"
     )
     assert result.exit_code == 0, result.output
 
 
 def test_deposit_delays(
     requests_mock, mocker, sample_archive, sample_metadata, mocked_time
 ):
     scenario = WebScenario()
 
     scenario.add_step(
-        "post", BASE_URL + "/testcol/", ENTRY_TEMPLATE.format(status="deposited")
+        "post", f"{BASE_URL}/testcol/", ENTRY_TEMPLATE.format(status="deposited")
     )
     scenario.add_step(
         "get",
-        BASE_URL + "/testcol/42/status/",
+        f"{BASE_URL}/testcol/42/status/",
         STATUS_TEMPLATE.format(status="verified", status_detail=""),
     )
     scenario.add_step(
         "get",
-        BASE_URL + "/testcol/42/status/",
+        f"{BASE_URL}/testcol/42/status/",
         STATUS_TEMPLATE.format(status="loading", status_detail=""),
     )
     scenario.add_step(
         "get",
-        BASE_URL + "/testcol/42/status/",
+        f"{BASE_URL}/testcol/42/status/",
         STATUS_TEMPLATE.format(status="done", status_detail=""),
     )
 
     scenario.install_mock(requests_mock)
 
     result = invoke(
         [
             "check-deposit",
             *COMMON_OPTIONS,
             "single",
             "--archive",
             sample_archive,
             "--metadata",
             sample_metadata,
         ]
     )
 
     assert result.output == (
         "DEPOSIT OK - Deposit took 30.00s and succeeded.\n"
         "| 'load_time' = 20.00s\n"
         "| 'total_time' = 30.00s\n"
         "| 'upload_time' = 0.00s\n"
         "| 'validation_time' = 10.00s\n"
     )
     assert result.exit_code == 0, result.output
 
 
 def test_deposit_delay_warning(
     requests_mock, mocker, sample_archive, sample_metadata, mocked_time
 ):
     scenario = WebScenario()
 
     scenario.add_step(
-        "post", BASE_URL + "/testcol/", ENTRY_TEMPLATE.format(status="deposited")
+        "post", f"{BASE_URL}/testcol/", ENTRY_TEMPLATE.format(status="deposited")
     )
     scenario.add_step(
         "get",
-        BASE_URL + "/testcol/42/status/",
+        f"{BASE_URL}/testcol/42/status/",
         STATUS_TEMPLATE.format(status="verified", status_detail=""),
     )
     scenario.add_step(
         "get",
-        BASE_URL + "/testcol/42/status/",
+        f"{BASE_URL}/testcol/42/status/",
         STATUS_TEMPLATE.format(status="done", status_detail=""),
     )
 
     scenario.install_mock(requests_mock)
 
     result = invoke(
         [
             "--warning",
             "15",
             "check-deposit",
             *COMMON_OPTIONS,
             "single",
             "--archive",
             sample_archive,
             "--metadata",
             sample_metadata,
         ],
         catch_exceptions=True,
     )
 
     assert result.output == (
         "DEPOSIT WARNING - Deposit took 20.00s and succeeded.\n"
         "| 'load_time' = 10.00s\n"
         "| 'total_time' = 20.00s\n"
         "| 'upload_time' = 0.00s\n"
         "| 'validation_time' = 10.00s\n"
     )
     assert result.exit_code == 1, result.output
 
 
 def test_deposit_delay_critical(
     requests_mock, mocker, sample_archive, sample_metadata, mocked_time
 ):
     scenario = WebScenario()
 
     scenario.add_step(
-        "post", BASE_URL + "/testcol/", ENTRY_TEMPLATE.format(status="deposited")
+        "post", f"{BASE_URL}/testcol/", ENTRY_TEMPLATE.format(status="deposited")
     )
     scenario.add_step(
         "get",
-        BASE_URL + "/testcol/42/status/",
+        f"{BASE_URL}/testcol/42/status/",
         STATUS_TEMPLATE.format(status="verified", status_detail=""),
     )
     scenario.add_step(
         "get",
-        BASE_URL + "/testcol/42/status/",
+        f"{BASE_URL}/testcol/42/status/",
         STATUS_TEMPLATE.format(status="done", status_detail=""),
         callback=lambda: time.sleep(60),
     )
 
     scenario.install_mock(requests_mock)
 
     result = invoke(
         [
             "--critical",
             "50",
             "check-deposit",
             *COMMON_OPTIONS,
             "single",
             "--archive",
             sample_archive,
             "--metadata",
             sample_metadata,
         ],
         catch_exceptions=True,
     )
 
     assert result.output == (
         "DEPOSIT CRITICAL - Deposit took 80.00s and succeeded.\n"
         "| 'load_time' = 70.00s\n"
         "| 'total_time' = 80.00s\n"
         "| 'upload_time' = 0.00s\n"
         "| 'validation_time' = 10.00s\n"
     )
     assert result.exit_code == 2, result.output
 
 
 def test_deposit_timeout(
     requests_mock, mocker, sample_archive, sample_metadata, mocked_time
 ):
     scenario = WebScenario()
 
     scenario.add_step(
         "post",
-        BASE_URL + "/testcol/",
+        f"{BASE_URL}/testcol/",
         ENTRY_TEMPLATE.format(status="deposited"),
         callback=lambda: time.sleep(1500),
     )
     scenario.add_step(
         "get",
-        BASE_URL + "/testcol/42/status/",
+        f"{BASE_URL}/testcol/42/status/",
         STATUS_TEMPLATE.format(status="verified", status_detail=""),
         callback=lambda: time.sleep(1500),
     )
     scenario.add_step(
         "get",
-        BASE_URL + "/testcol/42/status/",
+        f"{BASE_URL}/testcol/42/status/",
         STATUS_TEMPLATE.format(status="loading", status_detail=""),
         callback=lambda: time.sleep(1500),
     )
 
     scenario.install_mock(requests_mock)
 
     result = invoke(
         [
             "check-deposit",
             *COMMON_OPTIONS,
             "single",
             "--archive",
             sample_archive,
             "--metadata",
             sample_metadata,
         ],
         catch_exceptions=True,
     )
 
     assert result.output == (
         "DEPOSIT CRITICAL - Timed out while in status loading "
         "(4520.0s seconds since deposit started)\n"
         "| 'total_time' = 4520.00s\n"
         "| 'upload_time' = 1500.00s\n"
         "| 'validation_time' = 1510.00s\n"
     )
     assert result.exit_code == 2, result.output
 
 
 def test_deposit_rejected(
     requests_mock, mocker, sample_archive, sample_metadata, mocked_time
 ):
     scenario = WebScenario()
 
     scenario.add_step(
-        "post", BASE_URL + "/testcol/", ENTRY_TEMPLATE.format(status="deposited")
+        "post", f"{BASE_URL}/testcol/", ENTRY_TEMPLATE.format(status="deposited")
     )
     scenario.add_step(
         "get",
-        BASE_URL + "/testcol/42/status/",
+        f"{BASE_URL}/testcol/42/status/",
         STATUS_TEMPLATE.format(status="rejected", status_detail="booo"),
     )
 
     scenario.install_mock(requests_mock)
 
     result = invoke(
         [
             "check-deposit",
             *COMMON_OPTIONS,
             "single",
             "--archive",
             sample_archive,
             "--metadata",
             sample_metadata,
         ],
         catch_exceptions=True,
     )
 
     assert result.output == (
         "DEPOSIT CRITICAL - Deposit was rejected: booo\n"
         "| 'total_time' = 10.00s\n"
         "| 'upload_time' = 0.00s\n"
         "| 'validation_time' = 10.00s\n"
     )
     assert result.exit_code == 2, result.output
 
 
 def test_deposit_failed(
     requests_mock, mocker, sample_archive, sample_metadata, mocked_time
 ):
     scenario = WebScenario()
 
     scenario.add_step(
-        "post", BASE_URL + "/testcol/", ENTRY_TEMPLATE.format(status="deposited")
+        "post", f"{BASE_URL}/testcol/", ENTRY_TEMPLATE.format(status="deposited")
     )
     scenario.add_step(
         "get",
-        BASE_URL + "/testcol/42/status/",
+        f"{BASE_URL}/testcol/42/status/",
         STATUS_TEMPLATE.format(status="verified", status_detail=""),
     )
     scenario.add_step(
         "get",
-        BASE_URL + "/testcol/42/status/",
+        f"{BASE_URL}/testcol/42/status/",
         STATUS_TEMPLATE.format(status="loading", status_detail=""),
     )
     scenario.add_step(
         "get",
-        BASE_URL + "/testcol/42/status/",
+        f"{BASE_URL}/testcol/42/status/",
         STATUS_TEMPLATE.format(status="failed", status_detail="booo"),
     )
 
     scenario.install_mock(requests_mock)
 
     result = invoke(
         [
             "check-deposit",
             *COMMON_OPTIONS,
             "single",
             "--archive",
             sample_archive,
             "--metadata",
             sample_metadata,
         ],
         catch_exceptions=True,
     )
 
     assert result.output == (
         "DEPOSIT CRITICAL - Deposit loading failed: booo\n"
         "| 'load_time' = 20.00s\n"
         "| 'total_time' = 30.00s\n"
         "| 'upload_time' = 0.00s\n"
         "| 'validation_time' = 10.00s\n"
     )
     assert result.exit_code == 2, result.output
 
 
 def test_deposit_unexpected_status(
     requests_mock, mocker, sample_archive, sample_metadata, mocked_time
 ):
     scenario = WebScenario()
 
     scenario.add_step(
-        "post", BASE_URL + "/testcol/", ENTRY_TEMPLATE.format(status="deposited")
+        "post", f"{BASE_URL}/testcol/", ENTRY_TEMPLATE.format(status="deposited")
     )
     scenario.add_step(
         "get",
-        BASE_URL + "/testcol/42/status/",
+        f"{BASE_URL}/testcol/42/status/",
         STATUS_TEMPLATE.format(status="verified", status_detail=""),
     )
     scenario.add_step(
         "get",
-        BASE_URL + "/testcol/42/status/",
+        f"{BASE_URL}/testcol/42/status/",
         STATUS_TEMPLATE.format(status="loading", status_detail=""),
     )
     scenario.add_step(
         "get",
-        BASE_URL + "/testcol/42/status/",
+        f"{BASE_URL}/testcol/42/status/",
         STATUS_TEMPLATE.format(status="what", status_detail="booo"),
     )
 
     scenario.install_mock(requests_mock)
 
     result = invoke(
         [
             "check-deposit",
             *COMMON_OPTIONS,
             "single",
             "--archive",
             sample_archive,
             "--metadata",
             sample_metadata,
         ],
         catch_exceptions=True,
     )
 
     assert result.output == (
         "DEPOSIT CRITICAL - Deposit got unexpected status: what (booo)\n"
         "| 'load_time' = 20.00s\n"
         "| 'total_time' = 30.00s\n"
         "| 'upload_time' = 0.00s\n"
         "| 'validation_time' = 10.00s\n"
     )
     assert result.exit_code == 2, result.output