Fix some basic tech debt

.github/workflows/go.yml

@@ -8,7 +8,8 @@ on:
 
 jobs:
 
-  build:
+  test:
+    name: Test
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v2
@@ -20,3 +21,29 @@ jobs:
 
     - name: Test
       run: go test -v ./...
+
+  lint:
+    name: Lint
+    runs-on: ubuntu-latest
+    container: golangci/golangci-lint:v1.42
+    steps:
+      - uses: actions/checkout@v2
+
+      - name: Check linters are up to date
+        run: make test-update-linters
+
+      - name: golangci-lint
+        uses: golangci/golangci-lint-action@v2
+        with:
+          version: v1.42
+
+  codespell:
+    name: Spell Check
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - uses: codespell-project/actions-codespell@master
+      with:
+        skip: .git
+        check_filenames: true
+        check_hidden: true

.golangci.yml

@@ -0,0 +1,116 @@
+output:
+  sort-results: true
+
+issues:
+  exclude-use-default: false
+  max-same-issues: 0
+  max-issues-per-linter: 0
+  exclude-rules:
+    # False positive: https://github.com/kunwardeep/paralleltest/issues/8.
+    - linters:
+        - paralleltest
+      text: "does not use range value in test Run"
+
+linters-settings:
+  errcheck:
+    check-type-assertions: true
+    check-blank: true
+  gci:
+    local-prefixes: github.com/flatcar-linux/fleetlock
+  godot:
+    capital: true
+  gofumpt:
+    extra-rules: true
+  govet:
+    enable-all: true
+    disable:
+      - fieldalignment
+      - shadow
+  makezero:
+    always: true
+  nolintlint:
+    allow-leading-space: false
+    require-explanation: true
+    require-specific: true
+  wsl:
+    force-err-cuddling: true
+
+linters:
+  disable-all: false
+  disable:
+    # We do not have clearly defined error types yet.
+    - goerr113
+    # We do not require all used structs to have all fields initialized.
+    - exhaustivestruct
+    # This linters has been deprecated.
+    - interfacer
+    - maligned
+    - golint
+  enable:
+    - asciicheck
+    - bodyclose
+    - cyclop
+    - deadcode
+    - depguard
+    - dogsled
+    - dupl
+    - durationcheck
+    - errcheck
+    - errname
+    - errorlint
+    - exhaustive
+    - exportloopref
+    - forbidigo
+    - forcetypeassert
+    - funlen
+    - gci
+    - gochecknoglobals
+    - gochecknoinits
+    - gocognit
+    - goconst
+    - gocritic
+    - gocyclo
+    - godot
+    - godox
+    - gofmt
+    - gofumpt
+    - goheader
+    - goimports
+    - gomnd
+    - gomoddirectives
+    - gomodguard
+    - goprintffuncname
+    - ifshort
+    - importas
+    - ineffassign
+    - lll
+    - makezero
+    - misspell
+    - nakedret
+    - nestif
+    - nilerr
+    - nlreturn
+    - noctx
+    - nolintlint
+    - paralleltest
+    - prealloc
+    - predeclared
+    - promlinter
+    - revive
+    - rowserrcheck
+    - scopelint
+    - sqlclosecheck
+    - structcheck
+    - stylecheck
+    - tagliatelle
+    - testpackage
+    - thelper
+    - tparallel
+    - typecheck
+    - unconvert
+    - unparam
+    - varcheck
+    - wastedassign
+    - whitespace
+    - wrapcheck
+    - wsl

Makefile

@@ -1,2 +1,24 @@
-build:
+GOLANGCILINT := go run github.com/golangci/golangci-lint/cmd/golangci-lint@v1.42.1
+
+.PHONY: build
+build: ## Compiles CLI binary.
 	@go build -o ./fleetlockctl main.go
+
+.PHONY: test-working-tree-clean
+test-working-tree-clean: ## Checks if working directory is clean.
+	@test -z "$$(git status --porcelain)" || (echo "Commit all changes before running this target"; exit 1)
+
+.PHONY: update-linters
+update-linters: ## Updates list of linters in .golangci.yml file based on currently installed golangci-lint binary.
+	# Remove all enabled linters.
+	sed -i '/^  enable:/q0' .golangci.yml
+	# Then add all possible linters to config.
+	$(GOLANGCILINT) linters | grep -E '^\S+:' | cut -d: -f1 | sort | sed 's/^/    - /g' | grep -v -E "($$(grep '^  disable:' -A 100 .golangci.yml  | grep -E '    - \S+$$' | awk '{print $$2}' | tr \\n '|' | sed 's/|$$//g'))" >> .golangci.yml
+
+.PHONY: test-update-linters
+test-update-linters: test-working-tree-clean update-linters ## Verifies that list of linters in .golangci.yml file is up to date.
+	@test -z "$$(git status --porcelain)" || (echo "Linter configuration outdated. Run 'make update-linters' and commit generated changes to fix."; exit 1)
+
+.PHONY: help
+help: ## Prints help message.
+	@grep -E '^[a-zA-Z_-]+:.*?## .*$$' $(MAKEFILE_LIST) | awk 'BEGIN {FS = ":.*?## "}; {printf "\033[36m%-30s\033[0m %s\n", $$1, $$2}'

README.md

@@ -1,4 +1,4 @@
-## Fleetlock client
+## FleetLock client
 
 [![Go Reference](https://pkg.go.dev/badge/github.com/flatcar-linux/fleetlock.svg)](https://pkg.go.dev/github.com/flatcar-linux/fleetlock)
 [![Go](https://github.com/flatcar-linux/fleetlock/actions/workflows/go.yml/badge.svg?branch=main)](https://github.com/flatcar-linux/fleetlock/actions/workflows/go.yml)

cmd/lock.go

@@ -1,6 +1,7 @@
 package cmd
 
 import (
+	"context"
 	"fmt"
 	"net/http"
 
@@ -9,22 +10,23 @@ import (
 	"github.com/flatcar-linux/fleetlock/pkg/client"
 )
 
-var (
-	lock = &cobra.Command{
-		Use: "recursive-lock",
+func lock(group, id, url *string) *cobra.Command {
+	return &cobra.Command{
+		Use:   "recursive-lock",
+		Short: "Try to reserve (lock) a slot for rebooting",
 		RunE: func(cmd *cobra.Command, args []string) error {
 			httpClient := http.DefaultClient
 
-			c, err := client.New(url, group, id, httpClient)
+			c, err := client.New(*url, *group, *id, httpClient)
 			if err != nil {
 				return fmt.Errorf("building the client: %w", err)
 			}
 
-			if err := c.RecursiveLock(); err != nil {
+			if err := c.RecursiveLock(context.Background()); err != nil {
 				return fmt.Errorf("locking: %w", err)
 			}
 
 			return nil
 		},
 	}
-)
+}

cmd/root.go

@@ -1,20 +1,22 @@
+// Package cmd implements fleetlockctl CLI.
 package cmd
 
 import (
 	"github.com/spf13/cobra"
 )
 
-var (
-	group, id, url string
+// Command returns CLI command to be executed.
+func Command() *cobra.Command {
+	cli := &cobra.Command{Use: "fleetlockctl"}
 
-	Root = &cobra.Command{Use: "fleetlockctl"}
-)
+	var group, id, url string
+
+	cli.PersistentFlags().StringVarP(&group, "group", "g", "default", "FleetLock group")
+	cli.PersistentFlags().StringVarP(&id, "id", "i", "", "FleetLock instance ID (e.g. content of /etc/machine-id file)")
+	cli.PersistentFlags().StringVarP(&url, "url", "u", "", "FleetLock endpoint URL")
 
-func init() {
-	Root.PersistentFlags().StringVarP(&group, "group", "g", "default", "Fleet-Lock group")
-	Root.PersistentFlags().StringVarP(&id, "id", "i", "", "Fleet-Lock instance ID (/etc/machine-id for example)")
-	Root.PersistentFlags().StringVarP(&url, "url", "u", "", "Fleet-Lock endpoint URL")
+	cli.AddCommand(lock(&group, &id, &url))
+	cli.AddCommand(unlock(&group, &id, &url))
 
-	Root.AddCommand(lock)
-	Root.AddCommand(unlock)
+	return cli
 }

cmd/unlock.go

@@ -1,6 +1,7 @@
 package cmd
 
 import (
+	"context"
 	"fmt"
 	"net/http"
 
@@ -9,22 +10,23 @@ import (
 	"github.com/flatcar-linux/fleetlock/pkg/client"
 )
 
-var (
-	unlock = &cobra.Command{
-		Use: "unlock-if-held",
+func unlock(group, id, url *string) *cobra.Command {
+	return &cobra.Command{
+		Use:   "unlock-if-held",
+		Short: "Try to release (unlock) a slot that it was previously holding",
 		RunE: func(cmd *cobra.Command, args []string) error {
 			httpClient := http.DefaultClient
 
-			c, err := client.New(url, group, id, httpClient)
+			c, err := client.New(*url, *group, *id, httpClient)
 			if err != nil {
 				return fmt.Errorf("building the client: %w", err)
 			}
 
-			if err := c.UnlockIfHeld(); err != nil {
+			if err := c.UnlockIfHeld(context.Background()); err != nil {
 				return fmt.Errorf("unlocking: %w", err)
 			}
 
 			return nil
 		},
 	}
-)
+}

main.go

@@ -1,14 +1,13 @@
 package main
 
 import (
-	"fmt"
 	"os"
 
 	"github.com/flatcar-linux/fleetlock/cmd"
 )
 
 func main() {
-	if err := cmd.Root.Execute(); err != nil {
-		fmt.Fprintf(os.Stderr, "unable to execute command: %v", err)
+	if err := cmd.Command().Execute(); err != nil {
+		os.Exit(1)
 	}
 }