Account for PEP668 in pip invocations

Set the PIP_BREAK_SYSTEM_PACKAGES environment variable anywhere
pip is in use to account for PEP668 which would change pip to not
allow us to install in the system environment for newer versions of
pip.

src/ansible_builder/_target_scripts/assemble

@@ -20,6 +20,9 @@
 # at build time.
 set -ex
 
+# Account for PEP668
+export PIP_BREAK_SYSTEM_PACKAGES=1
+
 RELEASE=$(source /etc/os-release; echo $ID)
 
 # NOTE(pabelanger): Allow users to force either microdnf or dnf as a package

src/ansible_builder/_target_scripts/install-from-bindep

@@ -15,6 +15,10 @@
 # limitations under the License.
 
 set -ex
+
+# Account for PEP668
+export PIP_BREAK_SYSTEM_PACKAGES=1
+
 # NOTE(pabelanger): Allow users to force either microdnf or dnf as a package
 # manager.
 PKGMGR="${PKGMGR:-}"

src/ansible_builder/containerfile.py

@@ -235,6 +235,10 @@ def _insert_global_args(self, include_values: bool = False) -> None:
                 self.steps.append(f'ARG {arg}="{value}"')
             else:
                 self.steps.append(f"ARG {arg}")
+
+        # To account for PEP668 (https://peps.python.org/pep-0668/), always set this
+        # pip environment variable for every EE version in every stage.
+        self.steps.append("ENV PIP_BREAK_SYSTEM_PACKAGES=1")
         self.steps.append("")
 
     def _create_folder_copy_files(self) -> None:

test/unit/test_containerfile.py

@@ -207,3 +207,50 @@ def test__handle_additional_build_files(build_dir_and_ee_yml):
     config_dir = tmpdir / '_build' / 'configs'
     assert config_dir.exists()
     assert (config_dir / 'ansible.cfg').exists()
+
+
+def test_pep668_env_var_v1(build_dir_and_ee_yml):
+    """
+    Test that we add the pip env var to handle PEP668.
+    """
+    ee_data = """
+    version: 1
+    """
+    tmpdir, ee_path = build_dir_and_ee_yml(ee_data)
+    c = make_containerfile(tmpdir, ee_path, run_validate=True)
+    c.prepare()
+    assert "ENV PIP_BREAK_SYSTEM_PACKAGES=1" in c.steps
+
+
+def test_pep668_env_var_v2(build_dir_and_ee_yml):
+    """
+    Test that we add the pip env var to handle PEP668.
+    """
+    ee_data = """
+    version: 2
+    images:
+      base_image:
+        name: quay.io/user/mycustombaseimage:latest
+      builder_image:
+        name: quay.io/user/mycustombuilderimage:latest
+    """
+    tmpdir, ee_path = build_dir_and_ee_yml(ee_data)
+    c = make_containerfile(tmpdir, ee_path, run_validate=True)
+    c.prepare()
+    assert "ENV PIP_BREAK_SYSTEM_PACKAGES=1" in c.steps
+
+
+def test_pep668_env_var_v3(build_dir_and_ee_yml):
+    """
+    Test that we add the pip env var to handle PEP668.
+    """
+    ee_data = """
+    version: 3
+    images:
+      base_image:
+        name: quay.io/user/mycustombaseimage:latest
+    """
+    tmpdir, ee_path = build_dir_and_ee_yml(ee_data)
+    c = make_containerfile(tmpdir, ee_path, run_validate=True)
+    c.prepare()
+    assert "ENV PIP_BREAK_SYSTEM_PACKAGES=1" in c.steps