feat: add linters, minor refactors

.golangci.yml

@@ -9,13 +9,30 @@ outputs:
   format: colored-line-number
 
 linters:
-  enable:
-    - revive
-    - gosec
-    - lll
-    - wsl
+  presets:
+    - bugs
+    - comment
+    - complexity
+    - error
+    - format
+    - import
+    - metalinter
+    - module
+    - performance
+    - style
+    - test
+    - unused
+  disable:
+   - depguard # tbd
+   - exhaustruct # tbd
+   - wrapcheck # tbd
+   - tagliatelle # json case differs from output to output
+   - gochecknoinits # we need init for lambda
+   - gochecknoglobals # we need globals for lambda
 
 linters-settings:
   gosec:
     excludes:
       - G107
+  funlen:
+    lines: 80

go.mod

@@ -34,5 +34,3 @@ require (
 	github.com/google/uuid v1.6.0 // indirect
 	golang.org/x/net v0.30.0 // indirect
 )
-
-replace gopkg.in/yaml.v2 => gopkg.in/yaml.v2 v2.2.8

internal/atom.go

@@ -2,11 +2,15 @@ package internal
 
 import (
 	"encoding/xml"
+	"fmt"
 	"strings"
 	"time"
 )
 
-const NSAtom = "http://www.w3.org/2005/Atom"
+const (
+	NSAtom         = "http://www.w3.org/2005/Atom"
+	AtomLinksCount = 2
+)
 
 // Atom Docs - https://validator.w3.org/feed/docs/atom.html
 
@@ -25,7 +29,12 @@ type Atom struct {
 }
 
 func (atom Atom) XML() ([]byte, error) {
-	return xml.Marshal(atom)
+	data, err := xml.Marshal(atom)
+	if err != nil {
+		return nil, fmt.Errorf("can't marshal atom feed: %w", err)
+	}
+
+	return data, nil
 }
 
 type AtomGenerator struct {
@@ -68,7 +77,7 @@ type AtomLink struct {
 
 func ConvertFeedEntryToAtomEntry(entry *FeedEntry) AtomEntry {
 	var (
-		links      = make([]AtomLink, 0, 2)
+		links      = make([]AtomLink, 0, AtomLinksCount)
 		authors    = make([]AtomAuthor, len(entry.Authors))
 		categories = make([]AtomCategory, len(entry.Categories))
 	)
@@ -104,7 +113,7 @@ func ConvertFeedToAtom(feed *Feed) Atom {
 		entries[i] = item.Atom()
 	}
 
-	links := make([]AtomLink, 0, 2)
+	links := make([]AtomLink, 0, AtomLinksCount)
 
 	links = append(links, AtomLink{
 		Href: feed.Links.Alternate,

internal/errors.go

@@ -15,8 +15,9 @@ func (c *ErrorCollector) CollectMany(e []error) { *c = append(*c, e...) }
 
 func (c *ErrorCollector) CollectFrom(e ErrorCollector) { *c = append(*c, e...) }
 
-func (c *ErrorCollector) String() (err string) {
-	err = "Collected errors:\n"
+func (c *ErrorCollector) String() string {
+	err := "Collected errors:\n"
+
 	for i, e := range *c {
 		err += fmt.Sprintf("\tError %d: %s\n", i, e.Error())
 	}
@@ -25,7 +26,7 @@ func (c *ErrorCollector) String() (err string) {
 }
 
 func (c *ErrorCollector) Error() error {
-	return fmt.Errorf(c.String())
+	return fmt.Errorf("%s", c.String()) //nolint:err113
 }
 
 func (c *ErrorCollector) Size() int {

internal/files.go

@@ -11,6 +11,8 @@ type FeedFile struct {
 	Buffer   []byte
 }
 
+const filesCount = 3 // atom, rss, jsonfeed, json (will be added lately)
+
 var feedMimeType = map[string]string{
 	"atom":     "application/atom+xml",
 	"rss":      "application/rss+xml",
@@ -25,14 +27,14 @@ var feedBufferGenerators = map[string]func(feed Feed) ([]byte, error){
 
 func GenerateFeedFiles(feed Feed, domain string, name string) ([]FeedFile, []error) {
 	var (
-		generatedFiles   = make([]FeedFile, 0, 4)
-		generationErrors = make([]error, 0, 4)
+		generatedFiles   = make([]FeedFile, 0, filesCount)
+		generationErrors = make([]error, 0, filesCount)
 		formats          = []string{"atom", "rss", "jsonfeed"}
 	)
 
 	for _, format := range formats {
 		mime := feedMimeType[format]
-		filename := fmt.Sprintf("%s.%s", name, format)
+		filename := name + "." + format // "%s.%s"
 
 		if domain != "" {
 			feed.Links.Self = fmt.Sprintf("https://%s/%s", domain, filename)
@@ -69,3 +71,7 @@ func GenerateRawFile(entries interface{}, name string) (FeedFile, error) {
 func FormatFilePath(path string) string {
 	return strings.ReplaceAll(strings.ToLower(path), "_", "-")
 }
+
+func FormatAbstractFilePath(path string) string {
+	return "/" + path + ".*" // "/%s.*"
+}

internal/jsonfeed.go

@@ -38,9 +38,7 @@ type JSONFeedEntry struct {
 }
 
 func ConvertFeedEntryToJSONFeedEntry(entry *FeedEntry) JSONFeedEntry {
-	var (
-		authors = make([]JSONFeedAuthor, len(entry.Authors))
-	)
+	authors := make([]JSONFeedAuthor, len(entry.Authors))
 
 	for i, author := range entry.Authors {
 		authors[i] = JSONFeedAuthor{Name: author}

internal/processor.go

@@ -70,6 +70,7 @@ func (p *MainProcessor[ParamType]) Process(params []ParamType) error {
 		generatedPathsCollector = []string{}
 	)
 
+	//nolint:forbidigo // need for lambda logs
 	fmt.Printf(
 		"Starting processing %s with %d parameters and %d concurrency\n",
 		p.Name,
@@ -81,18 +82,21 @@ func (p *MainProcessor[ParamType]) Process(params []ParamType) error {
 		go p.ProcessChunk(generatedPathsChannel, errorsChannel, chunk, p.S3Client)
 	}
 
-	for i := 0; i < p.Concurrency; i++ {
+	for range p.Concurrency {
 		errorsCollector.CollectFrom(<-errorsChannel)
 
 		generatedPathsCollector = append(generatedPathsCollector, <-generatedPathsChannel...)
 	}
 
 	if len(generatedPathsCollector) > 0 {
+		//nolint:forbidigo // need for lambda logs
 		fmt.Printf("Updated paths (%d): %v\n", len(generatedPathsCollector), generatedPathsCollector)
 	}
 
 	if errorsCollector.Size() > 0 {
-		fmt.Printf("During execution %d errors occured\n", errorsCollector.Size())
+		//nolint:forbidigo // need for lambda logs
+		fmt.Printf("During execution %d errors occurred\n", errorsCollector.Size())
+
 		return errorsCollector.Error()
 	}
 

internal/rss.go

@@ -2,6 +2,7 @@ package internal
 
 import (
 	"encoding/xml"
+	"fmt"
 	"strings"
 	"time"
 )
@@ -19,7 +20,12 @@ type RSS struct {
 }
 
 func (rss RSS) XML() ([]byte, error) {
-	return xml.Marshal(rss)
+	data, err := xml.Marshal(rss)
+	if err != nil {
+		return nil, fmt.Errorf("can't marshal rss feed: %w", err)
+	}
+
+	return data, nil
 }
 
 type RSSChannel struct {
@@ -53,9 +59,7 @@ type RSSEntry struct {
 }
 
 func ConvertFeedEntryToRSSEntry(entry *FeedEntry) RSSEntry {
-	var (
-		image *RSSEnclosure
-	)
+	var image *RSSEnclosure
 
 	if entry.Image != "" {
 		image = &RSSEnclosure{URL: entry.Image, Length: 0, Type: "image/*"}

internal/s3.go

@@ -13,9 +13,7 @@ import (
 	"github.com/aws/aws-sdk-go-v2/service/s3"
 )
 
-var (
-	bucketName string
-)
+var bucketName string
 
 func init() {
 	bucketName = os.Getenv("BUCKET_NAME")

internal/slice.go

@@ -1,9 +1,5 @@
 package internal
 
-import (
-	"fmt"
-)
-
 func SplitSliceToChunks[T interface{}](arr []T, count int) [][]T {
 	var (
 		size   = int(float64(len(arr)) / float64(count))
@@ -12,32 +8,32 @@ func SplitSliceToChunks[T interface{}](arr []T, count int) [][]T {
 	)
 
 	pointer := 0
-	for i := 0; i < count; i++ {
+	for index := range count {
 		start := pointer
-		pointer = pointer + size
+		pointer += size
 
-		if i < exceed {
-			pointer = pointer + 1
+		if index < exceed {
+			pointer++
 		}
 
 		if pointer > len(arr) {
 			pointer = len(arr)
 		}
 
-		result[i] = make([]T, pointer-start)
-		copy(result[i], arr[start:pointer])
+		result[index] = make([]T, pointer-start)
+		copy(result[index], arr[start:pointer])
 	}
 
 	return result
 }
 
-func IsEqual[T interface{}](a, b []T, comparator func(a, b T) bool) bool {
-	if len(a) != len(b) {
+func IsEqual[T interface{}](first, second []T, comparator func(a, b T) bool) bool {
+	if len(first) != len(second) {
 		return false
 	}
 
-	for i := range a {
-		if !comparator(a[i], b[i]) {
+	for i := range first {
+		if !comparator(first[i], second[i]) {
 			return false
 		}
 	}
@@ -46,32 +42,33 @@ func IsEqual[T interface{}](a, b []T, comparator func(a, b T) bool) bool {
 }
 
 func CompareAndGetDiff[T interface{}](
-	old, new []T,
+	olditems, newitems []T,
 	keyfunc func(item T) string,
-) (diff []string, isEqual bool) {
-	om := make(map[string]int8, len(old))
+) ([]string, bool) {
+	changesmap := make(map[string]int8, len(olditems))
+	diff := []string{}
 
-	for _, olditem := range old {
-		om[keyfunc(olditem)] = om[keyfunc(olditem)] + 1
+	for _, olditem := range olditems {
+		changesmap[keyfunc(olditem)] = changesmap[keyfunc(olditem)] + 1
 	}
 
-	for _, newitem := range new {
+	for _, newitem := range newitems {
 		key := keyfunc(newitem)
 
-		val, found := om[key]
+		val, found := changesmap[key]
 		if found {
-			om[key] = val - 1
+			changesmap[key] = val - 1
 		} else {
-			diff = append(diff, fmt.Sprintf("+ %s", key))
+			diff = append(diff, "+ "+key)
 		}
 	}
 
-	for key, value := range om {
+	for key, value := range changesmap {
 		switch {
 		case value < 0:
-			diff = append(diff, fmt.Sprintf("+ %s", key))
+			diff = append(diff, "+ "+key)
 		case value > 0:
-			diff = append(diff, fmt.Sprintf("- %s", key))
+			diff = append(diff, "- "+key)
 		}
 	}