Adding upstream version 6.17.2.upstream/6.17.2

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 63 insertions, 0 deletions

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+# key-order
+
+This rule recommends reordering key names in ansible content to make
+code easier to maintain and less prone to errors.
+
+Here are some examples of common ordering checks done for tasks and handlers:
+
+- `name` must always be the first key for plays, tasks and handlers
+- on tasks, the `block`, `rescue` and `always` keys must be the last keys,
+  as this would avoid accidental miss-indentation errors between the last task
+  and the parent level.
+
+## Problematic code
+
+```yaml
+---
+- hosts: localhost
+  name: This is a playbook # <-- name key should be the first one
+  tasks:
+    - name: A block
+      block:
+        - name: Display a message
+          debug:
+            msg: "Hello world!"
+      when: true # <-- when key should be before block
+```
+
+## Correct code
+
+```yaml
+---
+- name: This is a playbook
+  hosts: localhost
+  tasks:
+    - name: A block
+      when: true
+      block:
+        - name: Display a message
+          debug:
+            msg: "Hello world!"
+```
+
+## Reasoning
+
+Making decisions about the optimal order of keys for ansible tasks or plays is
+no easy task, as we had a huge number of combinations to consider. This is also
+the reason why we started with a minimal sorting rule (name to be the first),
+and aimed to gradually add more fields later, and only when we find the proofs
+that one approach is likely better than the other.
+
+### Why I no longer can put `when` after a `block`?
+
+Try to remember that in real life, `block/rescue/always` have the habit to
+grow due to the number of tasks they host inside, making them exceed what a single screen. This would move the `when` task further away from the rest of the task properties. A `when` from the last task inside the block can
+easily be confused as being at the block level, or the reverse. When tasks are
+moved from one location to another, there is a real risk of moving the block
+level when with it.
+
+By putting the `when` before the `block`, we avoid that kind of risk. The same risk applies to any simple property at the task level, so that is why
+we concluded that the block keys must be the last ones.
+
+Another common practice was to put `tags` as the last property. Still, for the
+same reasons, we decided that they should not be put after block keys either.