chore: support golangci-lint in drone (#29)

Author: appleboy

.drone.yml

@@ -7,8 +7,15 @@ platform:
   arch: amd64
 
 steps:
+- name: lint
+  image: golangci/golangci-lint:v1.41.1
+  commands:
+  - golangci-lint run -v
+  volumes:
+  - name: gopath
+    path: /go
+
 - name: test
-  pull: always
   image: golang:1.16
   commands:
   - go test -v -covermode=atomic -coverprofile=coverage.out ./...
@@ -17,7 +24,6 @@ steps:
     path: /go
 
 - name: codecov
-  pull: always
   image: robertstettner/drone-codecov
   settings:
     token:

.golangci.yml

@@ -0,0 +1,38 @@
+linters:
+  disable-all: true
+  enable:
+    - bodyclose
+    - deadcode
+    - depguard
+    - dogsled
+    - dupl
+    - errcheck
+    - exportloopref
+    - exhaustive
+    - gochecknoinits
+    - goconst
+    - gocritic
+    - gocyclo
+    - gofmt
+    - goimports
+    - goprintffuncname
+    - gosec
+    - gosimple
+    - govet
+    - ineffassign
+    - lll
+    - misspell
+    - nakedret
+    - noctx
+    - nolintlint
+    - rowserrcheck
+    - staticcheck
+    - structcheck
+    - stylecheck
+    - typecheck
+    - unconvert
+    - unparam
+    - unused
+    - varcheck
+    - whitespace
+    - gofumpt