refac: atomic merge, lost-update race, RunPurge cost, duplicated walks

internal/domain/contenttype/fieldSchema.go

@@ -115,6 +115,21 @@ func (f Field) validDefault() bool {
 	return !f.Unique && f.Violation(f.Default) == ""
 }
 
+type MediaRef struct {
+	Field Field
+	ID    uint32
+}
+
+func MediaRefs(fields []Field, data map[string]any) []MediaRef {
+	var refs []MediaRef
+	for _, field := range MediaFields(fields) {
+		if id, set := MediaID(data[field.Key]); set {
+			refs = append(refs, MediaRef{Field: field, ID: id})
+		}
+	}
+	return refs
+}
+
 func MediaFields(fields []Field) []Field {
 	var media []Field
 	for _, field := range fields {

internal/domain/entry/entryData.go

@@ -51,12 +51,12 @@ func validateField(field contenttype.Field, data map[string]any) error {
 	value := data[field.Key]
 	if value == nil {
 		if field.Required {
-			return invalidField(field.Key, RuleRequired)
+			return InvalidField(field.Key, RuleRequired)
 		}
 		return nil
 	}
 	if rule := field.Violation(value); rule != "" {
-		return invalidField(field.Key, rule)
+		return InvalidField(field.Key, rule)
 	}
 	return nil
 }
@@ -76,7 +76,7 @@ func firstUnknownField(fields []contenttype.Field, data map[string]any) error {
 		return nil
 	}
 	sort.Strings(unknown)
-	return invalidField(unknown[0], RuleUnknownField)
+	return InvalidField(unknown[0], RuleUnknownField)
 }
 
 func UniqueValues(fields []contenttype.Field, data map[string]any) []UniqueValue {
@@ -91,10 +91,15 @@ func UniqueValues(fields []contenttype.Field, data map[string]any) []UniqueValue
 
 func MediaIDs(fields []contenttype.Field, data map[string]any) map[string]uint32 {
 	ids := map[string]uint32{}
-	for _, field := range contenttype.MediaFields(fields) {
-		if id, ok := contenttype.MediaID(data[field.Key]); ok {
-			ids[field.Key] = id
-		}
+	for _, ref := range contenttype.MediaRefs(fields, data) {
+		ids[ref.Field.Key] = ref.ID
 	}
 	return ids
 }
+
+func MissingMedia(field contenttype.Field, unchanged bool) error {
+	if unchanged {
+		return InvalidField(field.Key, RuleRequired)
+	}
+	return InvalidField(field.Key, contenttype.RuleType)
+}

internal/domain/entry/entryDomain.go

@@ -55,12 +55,8 @@ func (e FieldError) Unwrap() error {
 	return e.Cause
 }
 
-func invalidField(key string, rule string) error {
-	return FieldError{Key: key, Rule: rule, Cause: ErrInvalidEntry}
-}
-
 func InvalidField(key string, rule string) error {
-	return invalidField(key, rule)
+	return FieldError{Key: key, Rule: rule, Cause: ErrInvalidEntry}
 }
 
 func UniqueViolation(key string) error {

internal/domain/image/imageDomain.go

@@ -246,3 +246,52 @@ type Image struct {
 	CreatedAt    time.Time `json:"created_at"`
 	UpdatedAt    time.Time `json:"updated_at"`
 }
+
+func isStoredNameByte(char byte) bool {
+	return char == '-' || char == '_' || char == '.' || char >= '0' && char <= '9' || char >= 'a' && char <= 'z' || char >= 'A' && char <= 'Z'
+}
+
+func continuesName(body string, end int) bool {
+	if end >= len(body) || !isStoredNameByte(body[end]) {
+		return false
+	}
+	return body[end] != '.' || end+1 < len(body) && isStoredNameByte(body[end+1])
+}
+
+func storedNameMatches(body string, name string) []int {
+	var starts []int
+	if name == "" {
+		return starts
+	}
+	for from := 0; from < len(body); {
+		found := strings.Index(body[from:], name)
+		if found < 0 {
+			break
+		}
+		start := from + found
+		end := start + len(name)
+		from = start + 1
+		if start > 0 && isStoredNameByte(body[start-1]) || continuesName(body, end) {
+			continue
+		}
+		starts = append(starts, start)
+		from = end
+	}
+	return starts
+}
+
+func ContainsStoredName(body string, name string) bool {
+	return len(storedNameMatches(body, name)) > 0
+}
+
+func ReplaceStoredName(body string, from string, to string) string {
+	var rewritten strings.Builder
+	last := 0
+	for _, start := range storedNameMatches(body, from) {
+		rewritten.WriteString(body[last:start])
+		rewritten.WriteString(to)
+		last = start + len(from)
+	}
+	rewritten.WriteString(body[last:])
+	return rewritten.String()
+}

internal/domain/transaction/transactionDomain.go

@@ -0,0 +1,22 @@
+package transaction
+
+import (
+	"RenewCMS/internal/domain/article"
+	"RenewCMS/internal/domain/author"
+	"RenewCMS/internal/domain/entry"
+	"RenewCMS/internal/domain/image"
+	"RenewCMS/internal/domain/site"
+	"context"
+)
+
+type Repositories struct {
+	Articles article.Repository
+	Sites    site.Repository
+	Authors  author.Repository
+	Entries  entry.Repository
+	Images   image.Repository
+}
+
+type Transactor interface {
+	Run(ctx context.Context, work func(Repositories) error) error
+}