Add CI workflow to lint and check formatting of Go code

.github/workflows/check-go.yml

@@ -0,0 +1,71 @@
+name: Check Go
+
+# See: https://docs.github.com/en/actions/reference/events-that-trigger-workflows
+on:
+  push:
+    paths:
+      - ".github/workflows/check-go.yml"
+      - "Taskfile.yml"
+      - "**.go"
+  pull_request:
+    paths:
+      - ".github/workflows/check-go.yml"
+      - "Taskfile.yml"
+      - "**.go"
+  schedule:
+    # Run every Tuesday at 8 AM UTC to catch breakage caused by changes to tools.
+    - cron: "0 8 * * TUE"
+  workflow_dispatch:
+  repository_dispatch:
+
+jobs:
+  check-errors:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v2
+
+      - name: Install Task
+        uses: arduino/actions/setup-taskfile@master
+        with:
+          repo-token: ${{ secrets.GITHUB_TOKEN }}
+          version: 3.x
+
+      - name: Check for errors
+        run: task go:vet
+
+  check-style:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v2
+
+      - name: Install Task
+        uses: arduino/actions/setup-taskfile@master
+        with:
+          repo-token: ${{ secrets.GITHUB_TOKEN }}
+          version: 3.x
+
+      - name: Check style
+        run: task --silent go:lint
+
+  check-formatting:
+    runs-on: ubuntu-latest
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v2
+
+      - name: Install Task
+        uses: arduino/actions/setup-taskfile@master
+        with:
+          repo-token: ${{ secrets.GITHUB_TOKEN }}
+          version: 3.x
+
+      - name: Format code
+        run: task go:format
+
+      - name: Check formatting
+        run: git diff --color --exit-code

README.md

@@ -1,3 +1,5 @@
+[![Check Go status](https://github.com/arduino/libraries-repository-engine/actions/workflows/check-go.yml/badge.svg)](https://github.com/arduino/libraries-repository-engine/actions/workflows/check-go.yml)
+
 BUILD
 ----------------------------
 

Taskfile.yml

@@ -1,7 +1,7 @@
 # See: https://taskfile.dev/#/usage
 version: "3"
 
-env:
+vars:
   DEFAULT_GO_PACKAGES:
     sh: echo $(go list ./... | tr '\n' ' ')
 
@@ -15,3 +15,34 @@ tasks:
     desc: Run unit tests
     cmds:
       - go test -v -short -run '{{default ".*" .GO_TEST_REGEX}}' {{default "-timeout 10m -coverpkg=./... -covermode=atomic" .GO_TEST_FLAGS}} -coverprofile=coverage_unit.txt {{default .DEFAULT_GO_PACKAGES .GO_PACKAGES}}
+
+  go:check:
+    desc: Check for problems with Go code
+    deps:
+      - task: go:vet
+      - task: go:lint
+
+  go:vet:
+    desc: Check for errors in Go code
+    cmds:
+      - go vet {{default .DEFAULT_GO_PACKAGES .GO_PACKAGES}}
+
+  go:lint:
+    desc: Lint Go code
+    cmds:
+      - |
+        PROJECT_PATH="$PWD"
+        # `go get` and `go list` commands must be run from a temporary folder to avoid polluting go.mod
+        cd "$(mktemp -d "${TMPDIR-${TMP-/tmp}}/task-temporary-XXXXX")"
+        go get golang.org/x/lint/golint
+        GOLINT_PATH="$(go list -f '{{"{{"}}.Target{{"}}"}}' golang.org/x/lint/golint || echo "false")"
+        # `golint` must be run from the module folder
+        cd "$PROJECT_PATH"
+        "$GOLINT_PATH" \
+          {{default "-min_confidence 0.8 -set_exit_status" .GO_LINT_FLAGS}} \
+          {{default .DEFAULT_GO_PACKAGES .GO_PACKAGES}}
+
+  go:format:
+    desc: Format Go code
+    cmds:
+      - go fmt {{default .DEFAULT_GO_PACKAGES .GO_PACKAGES}}

libraries/bad_file_cleaner.go

@@ -7,6 +7,7 @@ import (
 	"path/filepath"
 )
 
+// FailIfHasUndesiredFiles returns an error if the folder contains any undesired files.
 func FailIfHasUndesiredFiles(folder string) error {
 	err := failIfContainsForbiddenFileInRoot(folder)
 	if err != nil {
@@ -15,10 +16,11 @@ func FailIfHasUndesiredFiles(folder string) error {
 	return failIfContainsExes(folder)
 }
 
-var FORBIDDEN_FILES = []string{".development"}
+// ForbiddenFiles is the names of the forbidden files.
+var ForbiddenFiles = []string{".development"}
 
 func failIfContainsForbiddenFileInRoot(folder string) error {
-	for _, file := range FORBIDDEN_FILES {
+	for _, file := range ForbiddenFiles {
 		if _, err := os.Stat(filepath.Join(folder, file)); err == nil {
 			return errors.New(file + " file found, skipping")
 		}
@@ -27,10 +29,11 @@ func failIfContainsForbiddenFileInRoot(folder string) error {
 	return nil
 }
 
-var PATTERNS = []string{"*.exe"}
+// Patterns is the file patterns of executables.
+var Patterns = []string{"*.exe"}
 
 func failIfContainsExes(folder string) error {
-	for _, pattern := range PATTERNS {
+	for _, pattern := range Patterns {
 		cmd := exec.Command("find", folder, "-type", "f", "-name", pattern)
 		output, err := cmd.CombinedOutput()
 		if err != nil {

libraries/clamav.go

@@ -31,6 +31,7 @@ func modifyEnv(env []string, key, value string) []string {
 	return envMapToSlice(envMap)
 }
 
+// RunAntiVirus scans the folder for viruses.
 func RunAntiVirus(folder string) ([]byte, error) {
 	cmd := exec.Command("clamdscan", "-i", folder)
 	cmd.Env = modifyEnv(os.Environ(), "LANG", "en")
@@ -42,7 +43,7 @@ func RunAntiVirus(folder string) ([]byte, error) {
 
 	output := string(out)
 	if strings.Index(output, "Infected files: 0") == -1 {
-		return out, errors.New("Infected files found!")
+		return out, errors.New("Infected files found")
 	}
 
 	return out, nil

libraries/cron/fill_missing_checksums.go

@@ -1,15 +1,16 @@
 package cron
 
 import (
-	"arduino.cc/repository/libraries/hash"
 	"io"
 	"net/http"
 	"os"
+
+	"arduino.cc/repository/libraries/hash"
 )
 
 /*
-   Check for missing size and checksum field and fills them
-   by downloading a copy of the file.
+FillMissingChecksumsForDownloadArchives checks for missing size and checksum field and fills them
+by downloading a copy of the file.
 */
 func FillMissingChecksumsForDownloadArchives(URL string, filename string) (int64, string, error) {
 	size, err := download(URL, filename)

libraries/db/db.go

@@ -55,10 +55,12 @@ type Dependency struct {
 	Version string
 }
 
+// New returns a new DB object.
 func New(libraryFile string) *DB {
 	return &DB{libraryFile: libraryFile}
 }
 
+// AddLibrary adds a library to the database.
 func (db *DB) AddLibrary(library *Library) error {
 	db.mutex.Lock()
 	defer db.mutex.Unlock()
@@ -70,6 +72,7 @@ func (db *DB) AddLibrary(library *Library) error {
 	return nil
 }
 
+// HasLibrary returns whether the database already contains the given library.
 func (db *DB) HasLibrary(libraryName string) bool {
 	db.mutex.Lock()
 	defer db.mutex.Unlock()
@@ -81,6 +84,7 @@ func (db *DB) hasLibrary(libraryName string) bool {
 	return found != nil
 }
 
+// FindLibrary returns the Library object for the given name.
 func (db *DB) FindLibrary(libraryName string) (*Library, error) {
 	db.mutex.Lock()
 	defer db.mutex.Unlock()
@@ -96,6 +100,7 @@ func (db *DB) findLibrary(libraryName string) (*Library, error) {
 	return nil, errors.New("library not found")
 }
 
+// AddRelease adds a library release to the database.
 func (db *DB) AddRelease(release *Release, repoURL string) error {
 	db.mutex.Lock()
 	defer db.mutex.Unlock()
@@ -120,6 +125,7 @@ func (db *DB) AddRelease(release *Release, repoURL string) error {
 	return nil
 }
 
+// HasReleaseByNameVersion returns whether the database contains a release for the given library and version number.
 func (db *DB) HasReleaseByNameVersion(libraryName string, libraryVersion string) bool {
 	db.mutex.Lock()
 	defer db.mutex.Unlock()
@@ -131,6 +137,7 @@ func (db *DB) hasReleaseByNameVersion(libraryName string, libraryVersion string)
 	return found != nil
 }
 
+// HasRelease returns whether the database already contains the given Release object.
 func (db *DB) HasRelease(release *Release) bool {
 	db.mutex.Lock()
 	defer db.mutex.Unlock()
@@ -141,6 +148,7 @@ func (db *DB) hasRelease(release *Release) bool {
 	return db.hasReleaseByNameVersion(release.LibraryName, release.Version.String())
 }
 
+// FindRelease returns the Release object from the database that matches the given object.
 func (db *DB) FindRelease(release *Release) (*Release, error) {
 	db.mutex.Lock()
 	defer db.mutex.Unlock()
@@ -156,6 +164,7 @@ func (db *DB) findReleaseByNameVersion(libraryName string, libraryVersion string
 	return nil, errors.New("library not found")
 }
 
+// LoadFromFile returns a DB object loaded from the given filename.
 func LoadFromFile(filename string) (*DB, error) {
 	file, err := os.Open(filename)
 	if err != nil {
@@ -170,6 +179,7 @@ func LoadFromFile(filename string) (*DB, error) {
 	return db, nil
 }
 
+// Load returns a DB object loaded from the given reader.
 func Load(r io.Reader) (*DB, error) {
 	decoder := json.NewDecoder(r)
 	db := new(DB)
@@ -180,6 +190,7 @@ func Load(r io.Reader) (*DB, error) {
 	return db, nil
 }
 
+// SaveToFile saves the database to a file.
 func (db *DB) SaveToFile() error {
 	db.mutex.Lock()
 	defer db.mutex.Unlock()
@@ -191,6 +202,7 @@ func (db *DB) SaveToFile() error {
 	return db.save(file)
 }
 
+// Save writes the database via the given writer.
 func (db *DB) Save(r io.Writer) error {
 	db.mutex.Lock()
 	defer db.mutex.Unlock()
@@ -222,6 +234,7 @@ func (db *DB) findLatestReleaseOfLibrary(lib *Library) (*Release, error) {
 	return found, nil
 }
 
+// FindReleasesOfLibrary returns the database's releases for the given Library object.
 func (db *DB) FindReleasesOfLibrary(lib *Library) []*Release {
 	db.mutex.Lock()
 	defer db.mutex.Unlock()
@@ -239,10 +252,12 @@ func (db *DB) findReleasesOfLibrary(lib *Library) []*Release {
 	return releases
 }
 
+// Commit saves the database to disk.
 func (db *DB) Commit() error {
 	return db.SaveToFile()
 }
 
+// Init loads a database from file and returns it.
 func Init(libraryFile string) *DB {
 	libs, err := LoadFromFile(libraryFile)
 	if err != nil {

libraries/db/versioning.go

@@ -2,28 +2,34 @@ package db
 
 import "encoding/json"
 
+// Version is the type for library versions.
 type Version struct {
 	version string
 }
 
+// Less returns whether the receiver version is lower than the argument.
 func (version *Version) Less(other Version) (bool, error) {
 	// TODO: apply semantic versioning
 	return version.version < other.version, nil
 }
 
+// String returns the version in string form.
 func (version *Version) String() string {
 	return version.version
 }
 
+// UnmarshalJSON parses the JSON-encoded argument and stores the result in the receiver.
 func (version *Version) UnmarshalJSON(data []byte) error {
 	return json.Unmarshal(data, &version.version)
 }
 
+// MarshalJSON returns the JSON encoding of the receiver.
 func (version *Version) MarshalJSON() ([]byte, error) {
 	// Encode version as a string
 	return json.Marshal(version.version)
 }
 
+// VersionFromString parses a string to a Version object.
 func VersionFromString(str string) Version {
 	return Version{version: str}
 }

libraries/file/SCCS.go

@@ -1,5 +1,6 @@
 package file
 
+// SCCSFiles is a map of folder names used internally by source code control systems.
 var SCCSFiles = map[string]bool{
 	"CVS":  true,
 	"RCS":  true,
@@ -8,6 +9,7 @@ var SCCSFiles = map[string]bool{
 	".hg":  true,
 	".bzr": true}
 
+// IsSCCS returns whether the given string is a folder name used internally by source code control systems.
 func IsSCCS(name string) bool {
 	return SCCSFiles[name]
 }