From ab8b831b385c085ff8b30b0ca423799f05fde691 Mon Sep 17 00:00:00 2001
From: per1234 <accounts@perglass.com>
Date: Thu, 6 May 2021 02:52:02 -0700
Subject: [PATCH 1/6] Fix error in Taskfile generation of packages list

An environment variable was used instead of the intended dynamic variable.
---
 Taskfile.yml | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/Taskfile.yml b/Taskfile.yml
index 6966653a..7eef9a28 100644
--- a/Taskfile.yml
+++ b/Taskfile.yml
@@ -1,7 +1,7 @@
 # See: https://taskfile.dev/#/usage
 version: "3"
 
-env:
+vars:
   DEFAULT_GO_PACKAGES:
     sh: echo $(go list ./... | tr '\n' ' ')
 

From f07b211e9bbce648d2d36700f5e41b2dd0595449 Mon Sep 17 00:00:00 2001
From: per1234 <accounts@perglass.com>
Date: Thu, 6 May 2021 02:53:25 -0700
Subject: [PATCH 2/6] Add CI workflow to lint and check formatting of Go code

On every push and pull request that affects relevant files, and periodically, lint and check formatting of the
repository's Go module.
---
 .github/workflows/check-go.yml | 71 ++++++++++++++++++++++++++++++++++
 README.md                      |  2 +
 Taskfile.yml                   | 31 +++++++++++++++
 3 files changed, 104 insertions(+)
 create mode 100644 .github/workflows/check-go.yml

diff --git a/.github/workflows/check-go.yml b/.github/workflows/check-go.yml
new file mode 100644
index 00000000..b62d24d9
--- /dev/null
+++ b/.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
diff --git a/README.md b/README.md
index f77c114f..7b9a9187 100644
--- a/README.md
+++ b/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
 ----------------------------
 
diff --git a/Taskfile.yml b/Taskfile.yml
index 7eef9a28..f673941e 100644
--- a/Taskfile.yml
+++ b/Taskfile.yml
@@ -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}}

From a83f6d992f1436a534edf4777d5bc4a2c602fae7 Mon Sep 17 00:00:00 2001
From: per1234 <accounts@perglass.com>
Date: Thu, 6 May 2021 05:12:10 -0700
Subject: [PATCH 3/6] Follow standard Golang naming conventions

As mandated by golint.
---
 libraries/bad_file_cleaner.go          |  8 +++----
 libraries/github_release_downloader.go | 10 ++++----
 libraries/repoarchive.go               |  2 +-
 libraries/repoclone.go                 |  4 ++--
 libraries/repoclone_test.go            |  2 +-
 libraries/repolist.go                  | 26 ++++++++++-----------
 libraries/repolist_test.go             | 32 +++++++++++++-------------
 libraries/zip/ziphelper.go             |  2 +-
 libraries/zip/ziphelper_test.go        |  2 +-
 sync_libraries.go                      |  6 ++---
 10 files changed, 47 insertions(+), 47 deletions(-)

diff --git a/libraries/bad_file_cleaner.go b/libraries/bad_file_cleaner.go
index c1cd0a3e..4be6d0f6 100644
--- a/libraries/bad_file_cleaner.go
+++ b/libraries/bad_file_cleaner.go
@@ -15,10 +15,10 @@ func FailIfHasUndesiredFiles(folder string) error {
 	return failIfContainsExes(folder)
 }
 
-var FORBIDDEN_FILES = []string{".development"}
+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 +27,10 @@ func failIfContainsForbiddenFileInRoot(folder string) error {
 	return nil
 }
 
-var PATTERNS = []string{"*.exe"}
+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 {
diff --git a/libraries/github_release_downloader.go b/libraries/github_release_downloader.go
index 53b43235..caa5bd8b 100644
--- a/libraries/github_release_downloader.go
+++ b/libraries/github_release_downloader.go
@@ -9,16 +9,16 @@ import (
 	"strings"
 )
 
-func GithubDownloadRelease(repoUrl, version string) (string, int64, string, error) {
+func GithubDownloadRelease(repoURL, version string) (string, int64, string, error) {
 	tempfile, err := ioutil.TempFile("", "github")
 	if err != nil {
 		return "", -1, "", err
 	}
 	defer os.Remove(tempfile.Name())
 
-	zipFileUrl := strings.Replace(repoUrl, ".git", "", 1) + "/archive/" + version + ".zip"
+	zipFileURL := strings.Replace(repoURL, ".git", "", 1) + "/archive/" + version + ".zip"
 
-	err = saveUrlIn(zipFileUrl, tempfile)
+	err = saveURLIn(zipFileURL, tempfile)
 	if err != nil {
 		return "", -1, "", err
 	}
@@ -34,10 +34,10 @@ func GithubDownloadRelease(repoUrl, version string) (string, int64, string, erro
 		return "", -1, "", err
 	}
 
-	return zipFileUrl, size, checksum, nil
+	return zipFileURL, size, checksum, nil
 }
 
-func saveUrlIn(url string, tempfile *os.File) error {
+func saveURLIn(url string, tempfile *os.File) error {
 	resp, err := http.Get(url)
 	if err != nil {
 		return err
diff --git a/libraries/repoarchive.go b/libraries/repoarchive.go
index c68018cd..5be8e88e 100644
--- a/libraries/repoarchive.go
+++ b/libraries/repoarchive.go
@@ -15,7 +15,7 @@ func ZipRepo(repoFolder string, baseFolder string, zipFolderName string) (string
 		return "", err
 	}
 	absoluteFileName := filepath.Join(baseFolder, zipFolderName+".zip")
-	if err := zip.ZipDirectory(repoFolder, zipFolderName, absoluteFileName); err != nil {
+	if err := zip.Directory(repoFolder, zipFolderName, absoluteFileName); err != nil {
 		os.Remove(absoluteFileName)
 		return "", err
 	}
diff --git a/libraries/repoclone.go b/libraries/repoclone.go
index 0fff9931..4c498d9a 100644
--- a/libraries/repoclone.go
+++ b/libraries/repoclone.go
@@ -25,11 +25,11 @@ type Repository struct {
 func CloneOrFetch(repoMeta *Repo, folderName string) (*Repository, error) {
 	repo := Repository{
 		FolderPath: folderName,
-		URL:        repoMeta.Url,
+		URL:        repoMeta.URL,
 	}
 
 	if _, err := os.Stat(folderName); os.IsNotExist(err) {
-		repo.Repository, err = git.PlainClone(folderName, false, &git.CloneOptions{URL: repoMeta.Url})
+		repo.Repository, err = git.PlainClone(folderName, false, &git.CloneOptions{URL: repoMeta.URL})
 		if err != nil {
 			return nil, err
 		}
diff --git a/libraries/repoclone_test.go b/libraries/repoclone_test.go
index 2dac1569..086cab01 100644
--- a/libraries/repoclone_test.go
+++ b/libraries/repoclone_test.go
@@ -9,7 +9,7 @@ import (
 )
 
 func TestCloneRepos(t *testing.T) {
-	meta := &Repo{Url: "https://github.com/arduino-libraries/Servo.git"}
+	meta := &Repo{URL: "https://github.com/arduino-libraries/Servo.git"}
 
 	subfolder, err := meta.AsFolder()
 	require.NoError(t, err)
diff --git a/libraries/repolist.go b/libraries/repolist.go
index 6b82ca24..f42c67d2 100644
--- a/libraries/repolist.go
+++ b/libraries/repolist.go
@@ -30,7 +30,7 @@ func loadRepoListFromFile(filename string) ([]*Repo, error) {
 			types := strings.Split(split[1], ",")
 			name := split[2]
 			repos = append(repos, &Repo{
-				Url:         url,
+				URL:         url,
 				Types:       types,
 				LibraryName: name,
 			})
@@ -46,7 +46,7 @@ type repoMatcher interface {
 
 type repoMatcherIfDotGit struct{}
 
-func (_ repoMatcherIfDotGit) Match(url string) bool {
+func (repoMatcherIfDotGit) Match(url string) bool {
 	return strings.Index(url, "https://") == 0 && strings.LastIndex(url, ".git") == len(url)-len(".git")
 }
 
@@ -69,7 +69,7 @@ type GitURLsError struct {
 }
 
 type Repo struct {
-	Url         string
+	URL         string
 	Types       []string
 	LibraryName string
 }
@@ -78,7 +78,7 @@ type Repo struct {
 // For example if the repo URL is https://github.com/example/lib.git this function
 // will return "github.com/example/lib"
 func (repo *Repo) AsFolder() (string, error) {
-	u, err := url.Parse(repo.Url)
+	u, err := url.Parse(repo.URL)
 	if err != nil {
 		return "", err
 	}
@@ -87,24 +87,24 @@ func (repo *Repo) AsFolder() (string, error) {
 	return folderName, nil
 }
 
-type ReposByUrl []*Repo
+type ReposByURL []*Repo
 
-func (r ReposByUrl) Len() int {
+func (r ReposByURL) Len() int {
 	return len(r)
 }
 
-func (r ReposByUrl) Swap(i, j int) {
+func (r ReposByURL) Swap(i, j int) {
 	r[i], r[j] = r[j], r[i]
 }
 
-func (r ReposByUrl) Less(i, j int) bool {
-	return r[i].Url < r[j].Url
+func (r ReposByURL) Less(i, j int) bool {
+	return r[i].URL < r[j].URL
 }
 
 func (err GitURLsError) Error() string {
 	error := bytes.NewBufferString("Following URL are unknown or unsupported git repos:\n")
 	for _, v := range err.Repos {
-		fmt.Fprintln(error, v.Url)
+		fmt.Fprintln(error, v.URL)
 	}
 
 	return error.String()
@@ -114,7 +114,7 @@ func filterReposBy(repos []*Repo, matcher repoMatcher) ([]*Repo, error) {
 	var filtered []*Repo
 	var wrong []*Repo
 	for _, repo := range repos {
-		if matcher.Match(repo.Url) {
+		if matcher.Match(repo.URL) {
 			filtered = append(filtered, repo)
 		} else {
 			wrong = append(wrong, repo)
@@ -171,9 +171,9 @@ func toListOfUniqueRepos(repos []*Repo) []*Repo {
 	var finalRepos []*Repo
 
 	for _, repo := range repos {
-		if _, contains := repoMap[repo.Url]; !contains {
+		if _, contains := repoMap[repo.URL]; !contains {
 			finalRepos = append(finalRepos, repo)
-			repoMap[repo.Url] = repo
+			repoMap[repo.URL] = repo
 		}
 	}
 
diff --git a/libraries/repolist_test.go b/libraries/repolist_test.go
index 207e9081..ed28b233 100644
--- a/libraries/repolist_test.go
+++ b/libraries/repolist_test.go
@@ -11,33 +11,33 @@ func TestListRepos(t *testing.T) {
 
 	require.Equal(t, 11, len(repos))
 
-	require.Equal(t, "https://github.com/PaulStoffregen/OctoWS2811.git", repos[0].Url)
-	require.Equal(t, "https://github.com/PaulStoffregen/AltSoftSerial.git", repos[1].Url)
-
-	require.Equal(t, "https://github.com/Cheong2K/ble-sdk-arduino.git", repos[2].Url)
-	require.Equal(t, "https://github.com/arduino-libraries/Bridge.git", repos[3].Url)
-	require.Equal(t, "https://github.com/adafruit/Adafruit_ADS1X15.git", repos[4].Url)
-	require.Equal(t, "https://github.com/adafruit/Adafruit_ADXL345.git", repos[5].Url)
-	require.Equal(t, "https://github.com/adafruit/Adafruit_AHRS.git", repos[6].Url)
-	require.Equal(t, "https://github.com/adafruit/Adafruit_AM2315.git", repos[7].Url)
-	require.Equal(t, "https://github.com/arduino-libraries/Scheduler.git", repos[8].Url)
-	require.Equal(t, "https://github.com/arduino-libraries/SD.git", repos[9].Url)
-	require.Equal(t, "https://github.com/arduino-libraries/Servo.git", repos[10].Url)
+	require.Equal(t, "https://github.com/PaulStoffregen/OctoWS2811.git", repos[0].URL)
+	require.Equal(t, "https://github.com/PaulStoffregen/AltSoftSerial.git", repos[1].URL)
+
+	require.Equal(t, "https://github.com/Cheong2K/ble-sdk-arduino.git", repos[2].URL)
+	require.Equal(t, "https://github.com/arduino-libraries/Bridge.git", repos[3].URL)
+	require.Equal(t, "https://github.com/adafruit/Adafruit_ADS1X15.git", repos[4].URL)
+	require.Equal(t, "https://github.com/adafruit/Adafruit_ADXL345.git", repos[5].URL)
+	require.Equal(t, "https://github.com/adafruit/Adafruit_AHRS.git", repos[6].URL)
+	require.Equal(t, "https://github.com/adafruit/Adafruit_AM2315.git", repos[7].URL)
+	require.Equal(t, "https://github.com/arduino-libraries/Scheduler.git", repos[8].URL)
+	require.Equal(t, "https://github.com/arduino-libraries/SD.git", repos[9].URL)
+	require.Equal(t, "https://github.com/arduino-libraries/Servo.git", repos[10].URL)
 	require.Error(t, err)
 
 	error, ok := err.(GitURLsError)
 	require.True(t, ok)
-	require.Equal(t, "https://github.com/arduino-libraries", error.Repos[0].Url)
-	require.Equal(t, "git@github.com:PaulStoffregen/Audio.git", error.Repos[1].Url)
+	require.Equal(t, "https://github.com/arduino-libraries", error.Repos[0].URL)
+	require.Equal(t, "git@github.com:PaulStoffregen/Audio.git", error.Repos[1].URL)
 }
 
 func TestRepoFolderPathDetermination(t *testing.T) {
-	repo := &Repo{Url: "https://github.com/arduino-libraries/Servo.git"}
+	repo := &Repo{URL: "https://github.com/arduino-libraries/Servo.git"}
 	f, err := repo.AsFolder()
 	require.NoError(t, err)
 	require.Equal(t, "github.com/arduino-libraries/Servo", f)
 
-	repo = &Repo{Url: "https://bitbucket.org/bjoern/arduino_osc"}
+	repo = &Repo{URL: "https://bitbucket.org/bjoern/arduino_osc"}
 	f, err = repo.AsFolder()
 	require.NoError(t, err)
 	require.Equal(t, "bitbucket.org/bjoern/arduino_osc", f)
diff --git a/libraries/zip/ziphelper.go b/libraries/zip/ziphelper.go
index 8501b6d9..e8c1cb9a 100644
--- a/libraries/zip/ziphelper.go
+++ b/libraries/zip/ziphelper.go
@@ -12,7 +12,7 @@ import (
 
 // ZipDirectory creates a new zip archive that contains a copy of "rootFolder" into "zipFile".
 // Inside the archive "rootFolder" will be renamed to "zipRootFolderName".
-func ZipDirectory(rootFolder string, zipRootFolderName string, zipFile string) error {
+func Directory(rootFolder string, zipRootFolderName string, zipFile string) error {
 	checks := func(path string, info os.FileInfo, err error) error {
 		info, err = os.Lstat(path)
 		if err != nil {
diff --git a/libraries/zip/ziphelper_test.go b/libraries/zip/ziphelper_test.go
index 1a8d5e83..8d9566f7 100644
--- a/libraries/zip/ziphelper_test.go
+++ b/libraries/zip/ziphelper_test.go
@@ -18,7 +18,7 @@ func TestZip(t *testing.T) {
 	require.NoError(t, os.Remove(zipFileName))
 	defer os.RemoveAll(zipFileName)
 
-	err = ZipDirectory("./testzip", "a_zip", zipFileName)
+	err = Directory("./testzip", "a_zip", zipFileName)
 	require.NoError(t, err)
 
 	zipFileReader, err := zip.OpenReader(zipFileName)
diff --git a/sync_libraries.go b/sync_libraries.go
index b4c520e1..cdf4a554 100644
--- a/sync_libraries.go
+++ b/sync_libraries.go
@@ -18,7 +18,7 @@ import (
 )
 
 type Config struct {
-	BaseDownloadUrl string
+	BaseDownloadURL string
 	LibrariesFolder string
 	LogsFolder      string
 	LibrariesDB     string
@@ -179,7 +179,7 @@ func setup(config *Config) {
 }
 
 func syncLibrary(logger *log.Logger, repoMetadata *libraries.Repo, libraryDb *db.DB) {
-	logger.Printf("Scraping %s", repoMetadata.Url)
+	logger.Printf("Scraping %s", repoMetadata.URL)
 
 	repoFolderName, err := repoMetadata.AsFolder()
 	if err != nil {
@@ -282,7 +282,7 @@ func syncLibraryTaggedRelease(logger *log.Logger, repo *libraries.Repository, ta
 		return fmt.Errorf("Error while calculating checksums: %s", err)
 	}
 	release := db.FromLibraryToRelease(library)
-	release.URL = config.BaseDownloadUrl + host + "/" + lib + "/" + zipName + ".zip"
+	release.URL = config.BaseDownloadURL + host + "/" + lib + "/" + zipName + ".zip"
 	release.ArchiveFileName = zipName + ".zip"
 	release.Size = size
 	release.Checksum = checksum

From 03f5f8d7f9910e114bcd68fcec2194b3e5ef4dca Mon Sep 17 00:00:00 2001
From: per1234 <accounts@perglass.com>
Date: Thu, 6 May 2021 05:14:16 -0700
Subject: [PATCH 4/6] Add missing doc comments

---
 libraries/bad_file_cleaner.go            |  3 +++
 libraries/clamav.go                      |  1 +
 libraries/cron/fill_missing_checksums.go |  4 ++--
 libraries/db/db.go                       | 15 +++++++++++++++
 libraries/db/versioning.go               |  6 ++++++
 libraries/file/SCCS.go                   |  2 ++
 libraries/github_release_downloader.go   |  1 +
 libraries/hash/checksumhelper.go         |  2 +-
 libraries/repoarchive.go                 |  2 ++
 libraries/repoclone.go                   |  3 +++
 libraries/repolist.go                    |  4 ++++
 libraries/zip/ziphelper.go               |  2 +-
 sync_libraries.go                        |  1 +
 13 files changed, 42 insertions(+), 4 deletions(-)

diff --git a/libraries/bad_file_cleaner.go b/libraries/bad_file_cleaner.go
index 4be6d0f6..bef3a8b8 100644
--- a/libraries/bad_file_cleaner.go
+++ b/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 {
@@ -15,6 +16,7 @@ func FailIfHasUndesiredFiles(folder string) error {
 	return failIfContainsExes(folder)
 }
 
+// ForbiddenFiles is the names of the forbidden files.
 var ForbiddenFiles = []string{".development"}
 
 func failIfContainsForbiddenFileInRoot(folder string) error {
@@ -27,6 +29,7 @@ func failIfContainsForbiddenFileInRoot(folder string) error {
 	return nil
 }
 
+// Patterns is the file patterns of executables.
 var Patterns = []string{"*.exe"}
 
 func failIfContainsExes(folder string) error {
diff --git a/libraries/clamav.go b/libraries/clamav.go
index b031eb1a..ed161e06 100644
--- a/libraries/clamav.go
+++ b/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")
diff --git a/libraries/cron/fill_missing_checksums.go b/libraries/cron/fill_missing_checksums.go
index 35b67a81..7ed2afa4 100644
--- a/libraries/cron/fill_missing_checksums.go
+++ b/libraries/cron/fill_missing_checksums.go
@@ -8,8 +8,8 @@ import (
 )
 
 /*
-   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)
diff --git a/libraries/db/db.go b/libraries/db/db.go
index d41ec5b8..d02bee93 100644
--- a/libraries/db/db.go
+++ b/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 {
diff --git a/libraries/db/versioning.go b/libraries/db/versioning.go
index 72be7768..7b4cd6ee 100644
--- a/libraries/db/versioning.go
+++ b/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}
 }
diff --git a/libraries/file/SCCS.go b/libraries/file/SCCS.go
index 089b0319..9355a602 100644
--- a/libraries/file/SCCS.go
+++ b/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]
 }
diff --git a/libraries/github_release_downloader.go b/libraries/github_release_downloader.go
index caa5bd8b..43736309 100644
--- a/libraries/github_release_downloader.go
+++ b/libraries/github_release_downloader.go
@@ -9,6 +9,7 @@ import (
 	"strings"
 )
 
+// GithubDownloadRelease downloads GitHub's archive of the release.
 func GithubDownloadRelease(repoURL, version string) (string, int64, string, error) {
 	tempfile, err := ioutil.TempFile("", "github")
 	if err != nil {
diff --git a/libraries/hash/checksumhelper.go b/libraries/hash/checksumhelper.go
index 50e022b9..dfdae2e7 100644
--- a/libraries/hash/checksumhelper.go
+++ b/libraries/hash/checksumhelper.go
@@ -7,7 +7,7 @@ import (
 	"os"
 )
 
-// Calculate hash for the file
+// Checksum calculates the hash for the file.
 func Checksum(filename string) (string, error) {
 	hasher := sha256.New()
 	file, err := os.Open(filename)
diff --git a/libraries/repoarchive.go b/libraries/repoarchive.go
index 5be8e88e..b916cfa0 100644
--- a/libraries/repoarchive.go
+++ b/libraries/repoarchive.go
@@ -9,6 +9,7 @@ import (
 	"arduino.cc/repository/libraries/zip"
 )
 
+// ZipRepo creates a ZIP archive of the repo folder and returns its path.
 func ZipRepo(repoFolder string, baseFolder string, zipFolderName string) (string, error) {
 	err := os.MkdirAll(baseFolder, os.FileMode(0755))
 	if err != nil {
@@ -23,6 +24,7 @@ func ZipRepo(repoFolder string, baseFolder string, zipFolderName string) (string
 	return absoluteFileName, nil
 }
 
+// ZipFolderName returns the name to use for the folder.
 func ZipFolderName(library *metadata.LibraryMetadata) string {
 	pattern := regexp.MustCompile("[^a-zA-Z0-9]")
 	return pattern.ReplaceAllString(library.Name, "_") + "-" + library.Version
diff --git a/libraries/repoclone.go b/libraries/repoclone.go
index 4c498d9a..237743df 100644
--- a/libraries/repoclone.go
+++ b/libraries/repoclone.go
@@ -22,6 +22,7 @@ type Repository struct {
 	URL        string
 }
 
+// CloneOrFetch returns a Repository object. If the repository is already present, it is opened. Otherwise, cloned.
 func CloneOrFetch(repoMeta *Repo, folderName string) (*Repository, error) {
 	repo := Repository{
 		FolderPath: folderName,
@@ -64,6 +65,7 @@ func CloneOrFetch(repoMeta *Repo, folderName string) (*Repository, error) {
 	return &repo, err
 }
 
+// GenerateLibraryFromRepo parses a repository and returns the library metadata.
 func GenerateLibraryFromRepo(repo *Repository) (*metadata.LibraryMetadata, error) {
 	bytes, err := ioutil.ReadFile(filepath.Join(repo.FolderPath, "library.properties"))
 	if err != nil {
@@ -88,6 +90,7 @@ func GenerateLibraryFromRepo(repo *Repository) (*metadata.LibraryMetadata, error
 	return library, nil
 }
 
+// UpdateLibrary adds a release to the library database.
 func UpdateLibrary(release *db.Release, repoURL string, libraryDb *db.DB) error {
 	var err error
 
diff --git a/libraries/repolist.go b/libraries/repolist.go
index f42c67d2..297ac7eb 100644
--- a/libraries/repolist.go
+++ b/libraries/repolist.go
@@ -64,10 +64,12 @@ func (_ repoMatcherIfGithub) Match(r string) bool {
 }
 */
 
+// GitURLsError is the type for the unknown or unsupported repositories data.
 type GitURLsError struct {
 	Repos []*Repo
 }
 
+// Repo is the type for the library repository data.
 type Repo struct {
 	URL         string
 	Types       []string
@@ -87,6 +89,7 @@ func (repo *Repo) AsFolder() (string, error) {
 	return folderName, nil
 }
 
+// ReposByURL is the type for the libraries repository data.
 type ReposByURL []*Repo
 
 func (r ReposByURL) Len() int {
@@ -180,6 +183,7 @@ func toListOfUniqueRepos(repos []*Repo) []*Repo {
 	return finalRepos
 }
 
+// ListRepos loads a list from the given filename.
 func ListRepos(reposFilename string) ([]*Repo, error) {
 	repos, err := loadRepoListFromFile(reposFilename)
 	if err != nil {
diff --git a/libraries/zip/ziphelper.go b/libraries/zip/ziphelper.go
index e8c1cb9a..dd6eeea5 100644
--- a/libraries/zip/ziphelper.go
+++ b/libraries/zip/ziphelper.go
@@ -10,7 +10,7 @@ import (
 	"arduino.cc/repository/libraries/file"
 )
 
-// ZipDirectory creates a new zip archive that contains a copy of "rootFolder" into "zipFile".
+// Directory creates a new zip archive that contains a copy of "rootFolder" into "zipFile".
 // Inside the archive "rootFolder" will be renamed to "zipRootFolderName".
 func Directory(rootFolder string, zipRootFolderName string, zipFile string) error {
 	checks := func(path string, info os.FileInfo, err error) error {
diff --git a/sync_libraries.go b/sync_libraries.go
index cdf4a554..dd6fa25d 100644
--- a/sync_libraries.go
+++ b/sync_libraries.go
@@ -17,6 +17,7 @@ import (
 	"github.com/go-git/go-git/v5/plumbing"
 )
 
+// Config is the type of the engine configuration.
 type Config struct {
 	BaseDownloadURL string
 	LibrariesFolder string

From 28f3f685636359925a8e91ba83142460ceee417a Mon Sep 17 00:00:00 2001
From: per1234 <accounts@perglass.com>
Date: Thu, 6 May 2021 05:14:38 -0700
Subject: [PATCH 5/6] Follow standard error message format conventions

As mandated by golint.
---
 libraries/clamav.go | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/libraries/clamav.go b/libraries/clamav.go
index ed161e06..9718e864 100644
--- a/libraries/clamav.go
+++ b/libraries/clamav.go
@@ -43,7 +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

From e4d3584d7bea2c98da46151517c5118b039ef1ab Mon Sep 17 00:00:00 2001
From: per1234 <accounts@perglass.com>
Date: Thu, 6 May 2021 05:15:54 -0700
Subject: [PATCH 6/6] Follow standard imports order

---
 libraries/cron/fill_missing_checksums.go | 3 ++-
 libraries/github_release_downloader.go   | 3 ++-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/libraries/cron/fill_missing_checksums.go b/libraries/cron/fill_missing_checksums.go
index 7ed2afa4..39ed6636 100644
--- a/libraries/cron/fill_missing_checksums.go
+++ b/libraries/cron/fill_missing_checksums.go
@@ -1,10 +1,11 @@
 package cron
 
 import (
-	"arduino.cc/repository/libraries/hash"
 	"io"
 	"net/http"
 	"os"
+
+	"arduino.cc/repository/libraries/hash"
 )
 
 /*
diff --git a/libraries/github_release_downloader.go b/libraries/github_release_downloader.go
index 43736309..25cf98ba 100644
--- a/libraries/github_release_downloader.go
+++ b/libraries/github_release_downloader.go
@@ -1,12 +1,13 @@
 package libraries
 
 import (
-	"arduino.cc/repository/libraries/hash"
 	"io"
 	"io/ioutil"
 	"net/http"
 	"os"
 	"strings"
+
+	"arduino.cc/repository/libraries/hash"
 )
 
 // GithubDownloadRelease downloads GitHub's archive of the release.