Add tljh_post_install hook

integration-tests/plugins/simplest/tljh_simplest.py

@@ -1,6 +1,9 @@
 """
 Simplest plugin that exercises all the hooks
 """
+from textwrap import dedent
+
+from tljh import systemd
 from tljh.hooks import hookimpl
 
 
@@ -39,4 +42,22 @@ def tljh_config_post_install(config):
 
 @hookimpl
 def tljh_custom_jupyterhub_config(c):
-    c.JupyterHub.authenticator_class = 'tmpauthenticator.TmpAuthenticator'
+    c.JupyterHub.authenticator_class = 'tmpauthenticator.TmpAuthenticator'
+
+
+@hookimpl
+def tljh_post_install():
+    post_install_service = dedent("""
+    [Unit]
+    Description=Post Install Test Service
+
+    [Service]
+    ExecStart=ls
+
+    [Install]
+    WantedBy=multi-user.target
+    """)
+    service = "post-install-test.service"
+    systemd.install_unit(service, post_install_service)
+    systemd.enable_service(service)
+    systemd.reload_daemon()

integration-tests/test_simplest_plugin.py

@@ -6,6 +6,7 @@ import requests
 import os
 import subprocess
 from tljh.config import CONFIG_FILE, USER_ENV_PREFIX, HUB_ENV_PREFIX
+from tljh.systemd import check_service_enabled
 
 yaml = YAML(typ='rt')
 
@@ -54,6 +55,7 @@ def test_config_hook():
 
     assert data['simplest_plugin']['present']
 
+
 def test_jupyterhub_config_hook():
     """
     Test that tmpauthenticator is enabled by our custom config plugin
@@ -61,3 +63,10 @@ def test_jupyterhub_config_hook():
     resp = requests.get('http://localhost/hub/tmplogin', allow_redirects=False)
     assert resp.status_code == 302
     assert resp.headers['Location'] == '/hub/spawn'
+
+
+def test_post_install_hook():
+    """
+    Test that the post-install-test systemd service is enabled
+    """
+    assert check_service_enabled("post-install-test")

tljh/hooks.py

@@ -58,4 +58,14 @@ def tljh_config_post_install(config):
     be the serialized contents of config, so try to not
     overwrite anything the user might have explicitly set.
     """
+    pass
+
+@hookspec
+def tljh_post_install():
+    """
+    Post install script to be executed after installation
+    and after all the other hooks.
+
+    This can be arbitrary Python code.
+    """
     pass

tljh/installer.py

@@ -405,6 +405,9 @@ def run_plugin_actions(plugin_manager, plugins):
         ))
         conda.ensure_pip_packages(USER_ENV_PREFIX, user_pip_packages)
 
+    # Custom post install actions
+    hook.tljh_post_install()
+
 
 def ensure_config_yaml(plugin_manager):
     """