cron: add integration tests (#59830)

* cron: add integration tests

Use faketime in order to reduce waiting time. Using opensuse15
container:

    Tuesday 30 July 2019  23:03:19 +0000 (0:00:05.410)       0:01:28.291 **********
    ===============================================================================
    cron : install cron and faketime packages ------------------------------ 78.65s
    cron : wait 70 seconds max ---------------------------------------------- 5.41s
    Gathering Facts --------------------------------------------------------- 0.97s
    cron : enable cron service ---------------------------------------------- 0.72s
    cron : Use faketime with cron service ----------------------------------- 0.71s
    cron : command ---------------------------------------------------------- 0.41s
    cron : create directory for cron drop-in file --------------------------- 0.41s
    cron : add cron task ---------------------------------------------------- 0.40s
    cron : command ---------------------------------------------------------- 0.25s
    cron : command ---------------------------------------------------------- 0.25s
    cron : include_vars ----------------------------------------------------- 0.06s

* cron test, simplify: use Environment instead ExecStart

Thanks to mscherer for the suggestion.

* clean up comment: remove reference to outdated path

$OUTPUT_DIR is a plain path which doesn't reference any other
environment variables

* cron test: display elapsed time

* cron test: display some logs in case of failure

* cron test: handle FreeBSD

* cron tests: add checks

test/integration/targets/cron/aliases

@@ -0,0 +1,3 @@
+destructive
+shippable/posix/group4
+skip/osx

test/integration/targets/cron/defaults/cron.debian.yml

@@ -0,0 +1,4 @@
+---
+cron_pkg: cron
+cron_service: cron
+list_pkg_files: dpkg -L

test/integration/targets/cron/defaults/cron.fedora.yml

@@ -0,0 +1,4 @@
+---
+cron_pkg: cronie
+cron_service: crond
+list_pkg_files: rpm -ql

test/integration/targets/cron/defaults/cron.freebsd.yml

@@ -0,0 +1,4 @@
+---
+cron_pkg:
+cron_service: cron
+list_pkg_files: pkg info --list-files

test/integration/targets/cron/defaults/cron.redhat.yml

@@ -0,0 +1,5 @@
+---
+cron_pkg: cronie
+cron_service: crond
+faketime_pkg:
+list_pkg_files: rpm -ql

test/integration/targets/cron/defaults/cron.suse.yml

@@ -0,0 +1,4 @@
+---
+cron_pkg: cron
+cron_service: cron
+list_pkg_files: rpm -ql

test/integration/targets/cron/defaults/main.yml

@@ -0,0 +1,2 @@
+---
+faketime_pkg: libfaketime

test/integration/targets/cron/tasks/main.yml

@@ -0,0 +1,173 @@
+- include_vars: "{{ lookup('first_found', search) }}"
+  vars:
+    search:
+      files:
+        - 'cron.{{ ansible_system | lower }}.yml'
+        - 'cron.{{ ansible_distribution | lower }}.yml'
+        - 'cron.{{ ansible_os_family | lower }}.yml'
+      paths:
+        - '../defaults/'
+
+- vars:
+    remote_dir: "{{ lookup('env', 'OUTPUT_DIR') }}"
+  block:
+    - name: install cron package
+      package:
+        name: '{{ cron_pkg }}'
+      when: cron_pkg|default(false, true)
+      register: cron_package_installed
+      until: cron_package_installed is success
+
+    - when: faketime_pkg|default(false, true)
+      block:
+        - name: install cron and faketime packages
+          package:
+            name: '{{ faketime_pkg }}'
+          register: faketime_package_installed
+          until: faketime_package_installed is success
+
+        - name: Find libfaketime path
+          shell: '{{ list_pkg_files }} {{ faketime_pkg }} | grep -F libfaketime.so.1'
+          args:
+            warn: false
+          register: libfaketime_path
+
+        - when: ansible_service_mgr == 'systemd'
+          block:
+            - name: create directory for cron drop-in file
+              file:
+                path: '/etc/systemd/system/{{ cron_service }}.service.d'
+                state: directory
+                owner: root
+                group: root
+                mode: 0755
+
+            - name: Use faketime with cron service
+              copy:
+                content: |-
+                  [Service]
+                  Environment=LD_PRELOAD={{ libfaketime_path.stdout_lines[0].strip() }}
+                  Environment="FAKETIME=+0y x10"
+                  Environment=RANDOM_DELAY=0
+                dest: '/etc/systemd/system/{{ cron_service }}.service.d/faketime.conf'
+                owner: root
+                group: root
+                mode: 0644
+
+        - when: ansible_system == 'FreeBSD'
+          name: Use faketime with cron service
+          copy:
+            content: |-
+              cron_env='LD_PRELOAD={{ libfaketime_path.stdout_lines[0].strip() }} FAKETIME="+0y x10"'
+            dest: '/etc/rc.conf.d/cron'
+            owner: root
+            group: wheel
+            mode: 0644
+
+    - name: enable cron service
+      service:
+        daemon-reload: "{{ (ansible_service_mgr == 'systemd')|ternary(true, omit) }}"
+        name: '{{ cron_service }}'
+        state: restarted
+
+    - name: add cron task (check mode enabled, cron task not already created)
+      cron:
+        name: test cron task
+        job: 'date > {{ remote_dir }}/cron_canary1'
+      check_mode: yes
+      register: check_mode_enabled_state_present
+
+    - assert:
+        that: check_mode_enabled_state_present is changed
+
+    - name: add cron task (check mode disabled, task hasn't already been created)
+      cron:
+        name: test cron task
+        job: 'date > {{ remote_dir }}/cron_canary1'
+      register: add_cron_task
+
+    - assert:
+        that: add_cron_task is changed
+
+    - name: add cron task (check mode enabled, cron task already exists)
+      cron:
+        name: test cron task
+        job: 'date > {{ remote_dir }}/cron_canary1'
+      check_mode: yes
+      register: check_mode_enabled_state_present_cron_task_already_exists
+
+    - assert:
+        that: check_mode_enabled_state_present_cron_task_already_exists is not changed
+
+    - name: add cron task (check mode disabled, cron task already created)
+      cron:
+        name: test cron task
+        job: 'date > {{ remote_dir }}/cron_canary1'
+      register: cron_task_already_created
+
+    - assert:
+        that: cron_task_already_created is not changed
+
+    - block:
+        - name: wait for canary creation
+          wait_for:
+            path: '{{ remote_dir }}/cron_canary1'
+            timeout: '{{ 20 if faketime_pkg else 70 }}'
+          register: wait_canary
+      always:
+        - name: display some logs in case of failure
+          command: 'journalctl -u {{ cron_service }}'
+          when: wait_canary is failed and ansible_service_mgr == 'systemd'
+
+    - debug:
+        msg: 'elapsed time waiting for canary: {{ wait_canary.elapsed }}'
+
+    - name: Check check_mode
+      cron:
+        name: test cron task
+        job: 'date > {{ remote_dir }}/cron_canary1'
+        state: absent
+      check_mode: yes
+      register: check_check_mode
+
+    - assert:
+        that: check_check_mode is changed
+
+    - name: Remove a cron task
+      cron:
+        name: test cron task
+        job: 'date > {{ remote_dir }}/cron_canary1'
+        state: absent
+      register: remove_task
+
+    - assert:
+        that: remove_task is changed
+
+    - name: 'cron task missing: check idempotence (check mode enabled, state=absent)'
+      cron:
+        name: test cron task
+        job: 'date > {{ remote_dir }}/cron_canary1'
+        state: absent
+      register: check_mode_enabled_remove_task_idempotence
+
+    - assert:
+        that: check_mode_enabled_remove_task_idempotence is not changed
+
+    - name: 'cron task missing: check idempotence (check mode disabled, state=absent)'
+      cron:
+        name: test cron task
+        job: 'date > {{ remote_dir }}/cron_canary1'
+        state: absent
+      register: remove_task_idempotence
+
+    - assert:
+        that: remove_task_idempotence is not changed
+
+    - name: Check that removing a cron task with cron_file and without specifying an user is allowed (#58493)
+      cron:
+        cron_file: unexistent_cron_file
+        state: absent
+      register: remove_cron_file
+
+    - assert:
+        that: remove_cron_file is not changed