chore(lint): Add Elvis Linter Config and Github Action

.github/workflows/elvis_lint.yaml

@@ -0,0 +1,13 @@
+name: Elvis Linter
+
+on: [push, pull_request]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v1
+      - run: |
+          echo "$GITHUB_BASE_REF"
+          echo "$GITHUB_HEAD_REF"
+           ./elvis-check.sh $GITHUB_BASE_REF $GITHUB_HEAD_REF

.gitignore

@@ -41,3 +41,4 @@ erlang.mk
 *.coverdata
 etc/emqx.conf.rendered
 Mnesia.*/
+elvis

elvis-check.sh

@@ -0,0 +1,36 @@
+#!/bin/bash
+
+set -euo pipefail
+
+echo "GITHUB_BASE_REF  $1"
+echo "GITHUB_HEAD_REF  $2"
+echo "$GITHUB_SHA"
+
+ELVIS_VERSION='1.0.0-emqx-1'
+
+base=${GITHUB_BASE_REF:-$1}
+elvis_version="${3:-$ELVIS_VERSION}"
+
+echo "$elvis_version"
+echo "$base"
+
+if [ ! -f ./elvis ] || [ "$(./elvis -v | grep -oE '[1-9]+\.[0-9]+\.[0-9]+\-emqx-[0-9]+')" != "$ELVIS_VERSION" ]; then
+    curl  -fLO "https://github.com/emqx/elvis/releases/download/$elvis_version/elvis"
+    chmod +x ./elvis
+fi
+
+git fetch origin "$base"
+git checkout -b refBranch HEAD
+git diff --name-only origin/"$base" refBranch
+
+bad_file_count=0
+for n in $(git diff --name-only origin/"$base" refBranch); do
+
+    if ! ./elvis rock "$n"; then
+        bad_file_count=$(( bad_file_count + 1))
+    fi
+done
+if [ $bad_file_count -gt 0 ]; then
+    echo "elvis: $bad_file_count errors"
+    exit 1
+fi

elvis.config

@@ -0,0 +1,31 @@
+[
+ {
+   elvis,
+   [
+    {config,
+     [
+      {dirs => ["apps"],
+        filter => "*.erl",
+        ruleset => erl_files,
+#        rules => [
+#            {elvis_style, max_module_length, #{}},
+#            {elvis_style, no_common_caveats_call, #{}}
+#          ]
+       },
+      {dirs => ["."],
+        filter => "Makefile",
+        ruleset => makefiles
+       },
+      {dirs => ["."],
+        filter => "rebar.config",
+        ruleset => rebar_config
+       },
+      {dirs => ["."],
+        filter => "elvis.config",
+        ruleset => elvis_config
+       }
+     ]
+    }
+   ]
+ }
+].