[lbry] ci: add golangci-lint action

.github/workflows/golangci-lint.yml

@@ -0,0 +1,57 @@
+name: golangci-lint
+
+env:
+  # go needs absolute directories, using the $HOME variable doesn't work here.
+  GOCACHE: /home/runner/work/go/pkg/build
+  GOPATH: /home/runner/work/go
+  GO_VERSION: '^1.17.0'
+
+on:
+  push:
+    tags:
+      - v*
+    branches:
+      - "*"
+  pull_request:
+    branches:
+      - "*"
+
+jobs:
+  golangci:
+    name: lint
+    runs-on: ubuntu-latest
+    steps:
+      - name: setup go ${{ env.GO_VERSION }}
+        uses: actions/setup-go@v2
+        with:
+          go-version: '${{ env.GO_VERSION }}'
+
+      - name: checkout source
+        uses: actions/checkout@v2
+
+      - name: compile code
+        run: go install -v ./...
+
+      - name: golangci-lint
+        uses: golangci/golangci-lint-action@v2
+        with:
+          # Optional: version of golangci-lint to use in form of v1.2 or v1.2.3 or `latest` to use the latest version
+          version: latest
+
+          # Optional: working directory, useful for monorepos
+          # working-directory: somedir
+
+          # Optional: golangci-lint command line arguments.
+          # args: --issues-exit-code=0
+
+          # Optional: show only new issues if it's a pull request. The default value is `false`.
+          # only-new-issues: true
+
+          # Optional: if set to true then the action will use pre-installed Go.
+          skip-go-installation: true
+
+          # Optional: if set to true then the action don't cache or restore ~/go/pkg.
+          # skip-pkg-cache: true
+
+          # Optional: if set to true then the action don't cache or restore ~/.cache/go-build.
+          # skip-build-cache: true

.golangci.yml

@@ -0,0 +1,152 @@
+linters-settings:
+  depguard:
+    list-type: blacklist
+    packages:
+      # logging is allowed only by logutils.Log, logrus
+      # is allowed to use only in logutils package
+      - github.com/sirupsen/logrus
+    packages-with-error-message:
+      - github.com/sirupsen/logrus: "logging is allowed only by logutils.Log"
+  dupl:
+    threshold: 100
+  funlen:
+    lines: 100
+    statements: 50
+  gci:
+    local-prefixes: github.com/golangci/golangci-lint
+  goconst:
+    min-len: 2
+    min-occurrences: 2
+  gocritic:
+    enabled-tags:
+      - diagnostic
+      - experimental
+      - opinionated
+      - performance
+      - style
+    disabled-checks:
+      - dupImport # https://github.com/go-critic/go-critic/issues/845
+      - ifElseChain
+      - octalLiteral
+      - whyNoLint
+      - wrapperFunc
+  gocyclo:
+    min-complexity: 15
+  goimports:
+    local-prefixes: github.com/golangci/golangci-lint
+  gomnd:
+    settings:
+      mnd:
+        # don't include the "operation" and "assign"
+        checks:
+          - argument
+          - case
+          - condition
+          - return
+  govet:
+    check-shadowing: true
+    settings:
+      printf:
+        funcs:
+          - (github.com/golangci/golangci-lint/pkg/logutils.Log).Infof
+          - (github.com/golangci/golangci-lint/pkg/logutils.Log).Warnf
+          - (github.com/golangci/golangci-lint/pkg/logutils.Log).Errorf
+          - (github.com/golangci/golangci-lint/pkg/logutils.Log).Fatalf
+  lll:
+    line-length: 140
+  maligned:
+    suggest-new: true
+  misspell:
+    locale: US
+  nolintlint:
+    allow-leading-space: true # don't require machine-readable nolint directives (i.e. with no leading space)
+    allow-unused: false # report any unused nolint directives
+    require-explanation: false # don't require an explanation for nolint directives
+    require-specific: false # don't require nolint directives to be specific about which linter is being skipped
+
+linters:
+  disable-all: true
+  enable:
+    - asciicheck
+    - bodyclose
+    # - deadcode
+    - depguard
+    # - dogsled
+    # - dupl
+    # - errcheck
+    # - exhaustive
+    - exportloopref
+    # - funlen
+    # - gochecknoglobals
+    # - gochecknoinits
+    # - gocognit
+    # - goconst
+    # - gocritic
+    # - gocyclo
+    # - godot
+    # - godox
+    # - goerr113
+    - gofmt
+    - goimports
+    # - gomnd
+    - goprintffuncname
+    # - gosec
+    # - gosimple
+    # - govet
+    # - ineffassign
+    # - interfacer
+    # - lll
+    # - maligned
+    # - misspell
+    - nakedret
+    # - nestif
+    # - noctx
+    # - nolintlint
+    # - prealloc
+    - rowserrcheck
+    # - revive
+    # - scopelint
+    # - staticcheck
+    # - structcheck
+    # - stylecheck
+    # - testpackage
+    # - typecheck
+    - unconvert
+    # - unparam
+    # - unused
+    # - varcheck
+    # - whitespace
+    # - wsl
+
+issues:
+  # Excluding configuration per-path, per-linter, per-text and per-source
+  exclude-rules:
+    - path: _test\.go
+      linters:
+        - gomnd
+
+    - path: pkg/golinters/errcheck.go
+      text: "SA1019: errCfg.Exclude is deprecated: use ExcludeFunctions instead"
+    - path: pkg/commands/run.go
+      text: "SA1019: lsc.Errcheck.Exclude is deprecated: use ExcludeFunctions instead"
+
+    # TODO must be removed after the release of the next version (v1.41.0)
+    - path: pkg/commands/run.go
+      linters:
+        - gomnd
+    # TODO must be removed after the release of the next version (v1.41.0)
+    - path: pkg/golinters/nolintlint/nolintlint.go
+      linters:
+        - gomnd
+    # TODO must be removed after the release of the next version (v1.41.0)
+    - path: pkg/printers/tab.go
+      linters:
+        - gomnd
+
+
+run:
+  skip-dirs:
+    - test/testdata_etc
+    - internal/cache
+    - internal/renameio
+    - internal/robustio