Use pre-commit with black + yamllint

* Added pre-commit config
  * Added yamllint config
  * Updated example YAML files to match the yamllint config
  * black'd existing Python code

.pre-commit-config.yaml

@@ -0,0 +1,26 @@
+repos:
+  - repo: https://github.com/pre-commit/pre-commit-hooks
+    rev: v4.3.0
+    hooks:
+      - id: check-case-conflict
+      - id: check-added-large-files
+      - id: check-merge-conflict
+      - id: mixed-line-ending
+        args: [ --fix=lf ]
+      - id: trailing-whitespace
+        args: [ --markdown-linebreak-ext=md ]
+      - id: debug-statements
+      - id: requirements-txt-fixer
+        args: [ requirements-dev.txt ]
+  - repo: https://github.com/adrienverge/yamllint
+    rev: v1.28.0
+    hooks:
+      - id: yamllint
+        types: [ file ]
+        files: ^(.*\.ya?ml(\.example)?|\.yamllint)$
+  - repo: https://github.com/psf/black
+    rev: 22.8.0
+    hooks:
+      - id: black
+        language_version: python3.9
+        args: [ -l , '88' ]

.yamllint

@@ -0,0 +1,47 @@
+rules:
+  braces: &braces_config
+    min-spaces-inside: 1
+    max-spaces-inside: 1
+    min-spaces-inside-empty: 0
+    max-spaces-inside-empty: 1
+  brackets: *braces_config
+  colons:
+    max-spaces-before: 0
+    max-spaces-after: 1
+  commas:
+    max-spaces-before: 1
+    min-spaces-after: 1
+    max-spaces-after: 1
+  comments:
+    require-starting-space: true
+    ignore-shebangs: true
+    min-spaces-from-content: 4
+  comments-indentation: { level: warning }
+  document-end: { present: false }
+  document-start: disable
+  empty-lines:
+    max: 2
+    max-start: 0
+    max-end: 0
+  empty-values:
+    forbid-in-block-mappings: true
+    forbid-in-flow-mappings: true
+  hyphens: { max-spaces-after: 1 }
+  indentation:
+    spaces: 2
+    indent-sequences: true
+  key-duplicates: enable
+  key-ordering: disable
+  line-length:
+    max: 88
+    allow-non-breakable-words: true
+    allow-non-breakable-inline-mappings: true
+  new-line-at-end-of-file: enable
+  new-lines:
+    type: unix
+  octal-values: disable
+  quoted-strings:
+    required: only-when-needed
+    quote-type: single
+  trailing-spaces: enable
+  truthy: { allowed-values: [ 'true' , 'false' ] }

example/00-data.yml

@@ -1,7 +1,7 @@
 all:
   hosts:
 
-    localhost:
+    localhost: {}
 
     # All of this should obviously come from some other inventory plugin.
 

example/01-test-reconstructed.yml

@@ -18,12 +18,12 @@ instructions:
     block:
       - when: inventory_hostname.startswith( 'evil' )
         action: fail
-        msg: "{{ inventory_hostname }} is obviously evil, skipping."
+        msg: '{{ inventory_hostname }} is obviously evil, skipping.'
     rescue:
       # Do not crash on redeemably evil VMs, but still skip them.
       - when: inv__data.unredeemable is defined
         action: fail
-        msg: "{{ reconstructed_error }}"
+        msg: '{{ reconstructed_error }}'
       - action: create_group
         group: reedmably_evil
         add_host: true
@@ -35,9 +35,9 @@ instructions:
     block:
       - action: create_group
         group: managed
-      - loop: [by_environment, by_network, by_failover_stack, by_service]
+      - loop: [ by_environment, by_network, by_failover_stack, by_service ]
         action: create_group
-        group: "{{ item }}"
+        group: '{{ item }}'
         parent: managed
 
   # Copy inv__data fields to separate inv__ variables
@@ -51,8 +51,8 @@ instructions:
       - subcomponent
     when: inv__data[item] is defined
     action: set_fact
-    name: "inv__{{ item }}"
-    value: "{{ inv__data[ item ] }}"
+    name: inv__{{ item }}
+    value: '{{ inv__data[ item ] }}'
 
   # Environment variable and groups
   - action: set_fact
@@ -64,7 +64,7 @@ instructions:
         )
       }}
   - action: create_group
-    group: "env_{{ inv__environment }}"
+    group: env_{{ inv__environment }}
     parent: by_environment
     add_host: true
 
@@ -80,33 +80,33 @@ instructions:
 
   # Network group
   - action: create_group
-    group: "net_{{ inv__network }}"
+    group: net_{{ inv__network }}
     parent: by_network
     add_host: true
 
   # Service group
   - action: set_var
     name: service_group
-    value: "svc_{{ inv__service }}"
+    value: svc_{{ inv__service }}
   - action: create_group
-    group: "{{ service_group }}"
+    group: '{{ service_group }}'
     parent: by_service
 
   # Component group. We add the host directly if there is no subcomponent.
   - when: inv__component is defined
     action: block
     vars:
-      comp_group: "svcm_{{ inv__service }}_{{ inv__component }}"
+      comp_group: svcm_{{ inv__service }}_{{ inv__component }}
     block:
-    - action: create_group
-      group: "{{ comp_group }}"
-      parent: "{{ service_group }}"
-    # Subcomponent group, or lack thereof.
-    - when: inv__subcomponent is not defined
-      action: add_host
-      group: "{{ comp_group }}"
-    - when: inv__subcomponent is defined
-      action: create_group
-      group: "svcm_{{ inv__service }}_{{ inv__subcomponent }}"
-      parent: "{{ comp_group }}"
-      add_host: true
+      - action: create_group
+        group: '{{ comp_group }}'
+        parent: '{{ service_group }}'
+      # Subcomponent group, or lack thereof.
+      - when: inv__subcomponent is not defined
+        action: add_host
+        group: '{{ comp_group }}'
+      - when: inv__subcomponent is defined
+        action: create_group
+        group: svcm_{{ inv__service }}_{{ inv__subcomponent }}
+        parent: '{{ comp_group }}'
+        add_host: true

inventory_plugins/reconstructed.py

@@ -893,11 +893,7 @@ class RciBlock(RcInstruction):
             output.extend("    " + s for s in instr.dump())
 
     def parse_action(self, record):
-        assert (
-            self._block is None
-            and self._rescue is None
-            and self._always is None
-        )
+        assert self._block is None and self._rescue is None and self._always is None
         if "block" not in record:
             raise AnsibleParserError("%s: missing 'block' field" % (self._action,))
         self._block = self.parse_block(record, "block")
@@ -938,11 +934,7 @@ class RciBlock(RcInstruction):
         return instructions
 
     def execute_action(self, host_name, variables):
-        assert not (
-            self._block is None
-            or self._rescue is None
-            or self._always is None
-        )
+        assert not (self._block is None or self._rescue is None or self._always is None)
         try:
             try:
                 self._display.vvv("- running 'block' instructions")

requirements-dev.txt

@@ -1,2 +1,3 @@
 ansible-core>=2.13
+pre-commit
 pytest>=7.1,<7.2