Add code quality tracking from Code Climate

Author: Mordil

.codeclimate.yml

@@ -0,0 +1,39 @@
+version: "2"
+checks:
+  argument-count:
+    config:
+      threshold: 6
+  complex-logic:
+    config:
+      threshold: 5
+  file-lines:
+    config:
+      threshold: 600
+  method-complexity:
+    config:
+      threshold: 6
+  method-count:
+    config:
+      threshold: 20
+  method-lines:
+    config:
+      threshold: 50
+  nested-control-flow:
+    config:
+      threshold: 4
+  return-statements:
+    enabled: false
+  similar-code:
+    config:
+      threshold: 40
+  identical-code:
+    config:
+      threshold: 40
+exclude_patterns:
+  - "docs/"
+  - ".gitlab-ci/"
+  - "scripts/"
+  - "Tests/"
+  - "*.md"
+  - "*.resolved"
+  - "*.txt"

.gitlab-ci/main.yml

@@ -1,4 +1,5 @@
 stages:
+  - Quality Checks
   - Platform Tests
   - Docs
 
@@ -32,6 +33,30 @@ pages:
     paths:
       - public
 
+Code Climate:
+  only:
+    refs:
+      - branches
+      - tags
+  stage: Quality Checks
+  image: docker:stable
+  services:
+    - docker:stable-dind
+  variables:
+    DOCKER_DRIVER: overlay2
+    CODE_QUALITY_IMAGE: "registry.gitlab.com/gitlab-org/security-products/codequality:latest"
+  script:
+    - docker pull --quiet "$CODE_QUALITY_IMAGE"
+    - docker run
+        --env SOURCE_CODE="$PWD"
+        --volume "$PWD":/code
+        --volume /var/run/docker.sock:/var/run/docker.sock
+        "$CODE_QUALITY_IMAGE" /code
+  artifacts:
+    expire_in: 1 week
+    reports:
+      codequality: gl-code-quality-report.json
+
 Ubuntu Bionic:
   stage: Platform Tests
   trigger:

README.md

@@ -2,12 +2,16 @@
 <p><img src="https://gitlab.com/Mordil/swift-redi-stack/wikis/uploads/cb4c517e40bd2f5ab796f1093efbd697/RediStack_social-preview_transparent.png" width="350" alt="RediStack logo"></p>
 
 <p>
-    <a href="https://gitlab.com/Mordil/swift-redi-stack/pipelines"><img src="https://gitlab.com/Mordil/swift-redi-stack/badges/master/pipeline.svg" alt="Build Status"></a>
     <a href="https://github.com/swift-server/sswg/blob/master/process/incubation.md#sandbox-level"><img src="https://img.shields.io/badge/sswg-sandbox-lightgrey.svg" alt="SSWG Maturity"></a>
     <a href="https://gitlab.com/Mordil/swift-redi-stack/blob/master/LICENSE.txt"><img src="https://img.shields.io/badge/License-Apache%202.0-yellow.svg" alt="Apache 2 License"></a>
     <a href="https://swift.org"><img src="https://img.shields.io/badge/Swift-5.0+-orange.svg" alt="Swift 5.0+"></a>
     <a href="https://redis.io"><img src="https://img.shields.io/badge/Redis-5.0-red.svg" alt="Redis 5.0"></a>
 </p>
+
+<p>
+    <a href="https://gitlab.com/Mordil/swift-redi-stack/pipelines"><img src="https://gitlab.com/Mordil/swift-redi-stack/badges/master/pipeline.svg" alt="Build Status"></a>
+    <a href="https://codeclimate.com/github/Mordil/swift-redi-stack/maintainability"><img src="https://api.codeclimate.com/v1/badges/3ff84c8d384b01cb5875/maintainability" /></a>
+</p>
 </div>
 
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