internal/board/card.go

@@ -1,15 +1,5 @@
 package board
 
-import "fmt"
-
-type CardNotExistError struct {
-	ID int
-}
-
-func (e CardNotExistError) Error() string {
-	return fmt.Sprintf("card ID '%d' does not exist in the database", e.ID)
-}
-
 // Card represents a card on a Kanban board.
 type Card struct {
 	ID          int
@@ -18,12 +8,23 @@ type Card struct {
 	Created     string
 }
 
-// UpdateId updates the ID of the Card value.
+// SetID updates the ID of the Card value only if
-func (c *Card) UpdateId(id int) {
+// the ID is < 1 (i.e. unset).
-	c.ID = id
+func (c *Card) SetID(id int) error {
+	if id < 1 {
+		return InvalidIDError{id}
 	}
 
-// Id returns the ID of the Card value.
+	if c.ID > 0 {
-func (c *Card) Id() int {
+		return IDAlreadySetError{}
+	}
+
+	c.ID = id
+
+	return nil
+}
+
+// GetID returns the ID of the Card value.
+func (c *Card) GetID() int {
 	return c.ID
 }

internal/board/errors.go

@@ -0,0 +1,53 @@
+package board
+
+import "fmt"
+
+// CardNotExistError is returned when a card does not exist in the database.
+type CardNotExistError struct {
+	ID int
+}
+
+func (e CardNotExistError) Error() string {
+	return fmt.Sprintf("card ID '%d' does not exist in the database", e.ID)
+}
+
+// InvalidIDError is an error for when an attempt to set an ID lower than 1 is made.
+type InvalidIDError struct {
+	ID int
+}
+
+func ( e InvalidIDError) Error() string {
+	return fmt.Sprintf("'%d' is an invalid ID", e.ID)
+}
+
+// IDAlreadySetError is an error for when an attempt is made to set an ID that has already been set.
+type IDAlreadySetError struct {}
+
+func (e IDAlreadySetError) Error() string {
+	return "the item's ID is already set"
+}
+
+// StatusListEmptyError is an error for unexpected empty list of statuses.
+type StatusListEmptyError struct{}
+
+func (e StatusListEmptyError) Error() string {
+	return "the status list must not be empty"
+}
+
+// StatusNotExistError is an error for when a status cannot be found in the database.
+type StatusNotExistError struct {
+	ID int
+}
+
+func (e StatusNotExistError) Error() string {
+	return fmt.Sprintf("status ID '%d' does not exist in the database", e.ID)
+}
+
+// StatusNotEmptyError is an error for when an attempt is made to delete non-empty statuses.
+type StatusNotEmptyError struct {
+	ID int
+}
+
+func (e StatusNotEmptyError) Error() string {
+	return fmt.Sprintf("status ID '%d' must contain no cards before deletion", e.ID)
+}

internal/board/status.go

@@ -1,32 +1,9 @@
 package board
 
 import (
-	"fmt"
 	"sort"
 )
 
-type StatusListEmptyError struct{}
-
-func (e StatusListEmptyError) Error() string {
-	return "the status list must not be empty"
-}
-
-type StatusNotExistError struct {
-	ID int
-}
-
-func (e StatusNotExistError) Error() string {
-	return fmt.Sprintf("status ID '%d' does not exist in the database", e.ID)
-}
-
-type StatusNotEmptyError struct {
-	ID int
-}
-
-func (e StatusNotEmptyError) Error() string {
-	return fmt.Sprintf("status ID '%d' must contain no cards before deletion", e.ID)
-}
-
 // Status represents the status of the Kanban board.
 type Status struct {
 	ID       int
@@ -36,12 +13,22 @@ type Status struct {
 }
 
 // UpdateID updates the ID of the Status value.
-func (s *Status) UpdateId(id int) {
+func (s *Status) SetID(id int) error {
-	s.ID = id
+	if id < 1 {
+		return InvalidIDError{id}
 	}
 
-// Id returns the ID of the Status value.
+	if s.ID > 0 {
-func (s *Status) Id() int {
+		return IDAlreadySetError{}
+	}
+
+	s.ID = id
+
+	return nil
+}
+
+// GetID returns the ID of the Status value.
+func (s *Status) GetID() int {
 	return s.ID
 }
 

internal/db/database.go

@@ -18,8 +18,8 @@ const (
 )
 
 type BoltItem interface {
-	UpdateId(int)
+	SetID(int) error
-	Id() int
+	GetID() int
 }
 
 // OpenDatabase opens the database, at a given path, for reading and writing.
@@ -65,7 +65,7 @@ func Read(db *bolt.DB, bucketName string, itemID int) ([]byte, error) {
 
 		return nil
 	}); err != nil {
-		return nil, fmt.Errorf("error while reading the Bolt item from the database, %w", err)
+		return nil, fmt.Errorf("error while reading the Bolt item from the database; %w", err)
 	}
 
 	return data, nil
@@ -116,13 +116,13 @@ func ReadAll(db *bolt.DB, bucketName string) ([][]byte, error) {
 
 			return nil
 		}); err != nil {
-			return fmt.Errorf("unable to load status, %w", err)
+			return fmt.Errorf("unable to load the Bolt item; %w", err)
 		}
 
 		return nil
 	})
 	if err != nil {
-		return nil, fmt.Errorf("error while loading statuses from the database, %w", err)
+		return nil, fmt.Errorf("error while loading the Bolt items from the database; %w", err)
 	}
 
 	return output, nil
@@ -140,12 +140,15 @@ func Write(db *bolt.DB, bucketName string, item BoltItem) (int, error) {
 			return bucketNotExistError{bucket: string(bucketNameBytes)}
 		}
 
-		if item.Id() < 1 {
+		if item.GetID() < 1 {
 			var id uint64
 			if id, err = bucket.NextSequence(); err != nil {
-				return fmt.Errorf("unable to generate an ID for the card, %w", err)
+				return fmt.Errorf("unable to generate an ID for the Bolt item; %w", err)
+			}
+
+			if err = item.SetID(int(id)); err != nil {
+				return fmt.Errorf("unable to set the generated ID to the Bolt item; %w", err)
 			}
-			item.UpdateId(int(id))
 		}
 
 		buf := new(bytes.Buffer)
@@ -154,17 +157,17 @@ func Write(db *bolt.DB, bucketName string, item BoltItem) (int, error) {
 			return fmt.Errorf("unable to encode data, %w", err)
 		}
 
-		if err = bucket.Put([]byte(strconv.Itoa(item.Id())), buf.Bytes()); err != nil {
+		if err = bucket.Put([]byte(strconv.Itoa(item.GetID())), buf.Bytes()); err != nil {
-			return fmt.Errorf("unable to write the card to the bucket, %w", err)
+			return fmt.Errorf("unable to write the Bolt item to the bucket; %w", err)
 		}
 
 		return nil
 	})
 	if err != nil {
-		return 0, fmt.Errorf("error while saving the card to the database, %w", err)
+		return 0, fmt.Errorf("error while saving the Bolt item to the database; %w", err)
 	}
 
-	return item.Id(), nil
+	return item.GetID(), nil
 }
 
 // WriteMany saves one or more Bolt items to the status bucket.
@@ -187,12 +190,15 @@ func WriteMany(database *bolt.DB, bucketName string, items []BoltItem) ([]int, e
 		for ind, item := range items {
 			var err error
 
-			if item.Id() < 1 {
+			if item.GetID() < 1 {
 				var id uint64
 				if id, err = bucket.NextSequence(); err != nil {
 					return fmt.Errorf("unable to generate ID, %w", err)
 				}
-				item.UpdateId(int(id))
+
+				if err = item.SetID(int(id)); err != nil {
+					return fmt.Errorf("unable to set the generated ID to the Bolt item; %w", err)
+				}
 			}
 
 			buf := new(bytes.Buffer)
@@ -201,11 +207,11 @@ func WriteMany(database *bolt.DB, bucketName string, items []BoltItem) ([]int, e
 				return fmt.Errorf("unable to encode data, %w", err)
 			}
 
-			if err = bucket.Put([]byte(strconv.Itoa(item.Id())), buf.Bytes()); err != nil {
+			if err = bucket.Put([]byte(strconv.Itoa(item.GetID())), buf.Bytes()); err != nil {
 				return fmt.Errorf("unable to add the Bolt Item to the %s bucket, %w", bucketName, err)
 			}
 
-			ids[ind] = item.Id()
+			ids[ind] = item.GetID()
 		}
 
 		return nil
@@ -229,12 +235,12 @@ func Delete(db *bolt.DB, bucketName string, itemID int) error {
 		}
 
 		if err := bucket.Delete([]byte(strconv.Itoa(itemID))); err != nil {
-			return fmt.Errorf("an error occurred when deleting Bolt item '%d', %w", itemID, err)
+			return fmt.Errorf("an error occurred when deleting Bolt item '%d'; %w", itemID, err)
 		}
 
 		return nil
 	}); err != nil {
-		return fmt.Errorf("error deleting data from the '%s' bucket, %w", bucketName, err)
+		return fmt.Errorf("error deleting data from the '%s' bucket; %w", bucketName, err)
 	}
 
 	return nil
@@ -245,7 +251,7 @@ func mkDataDir(path string) error {
 	dir := filepath.Dir(path)
 
 	if err := os.MkdirAll(dir, 0o700); err != nil {
-		return fmt.Errorf("error while making directory %s, %w", dir, err)
+		return fmt.Errorf("error while making directory %s; %w", dir, err)
 	}
 
 	return nil
@@ -258,14 +264,14 @@ func ensureBuckets(db *bolt.DB) error {
 	err := db.Update(func(tx *bolt.Tx) error {
 		for _, v := range buckets {
 			if _, err := tx.CreateBucketIfNotExists([]byte(v)); err != nil {
-				return fmt.Errorf("unable to ensure that %s bucket is created in the database, %w", v, err)
+				return fmt.Errorf("unable to ensure that %s bucket is created in the database; %w", v, err)
 			}
 		}
 
 		return nil
 	})
 	if err != nil {
-		return fmt.Errorf("error while ensuring buckets exist in the database, %w", err)
+		return fmt.Errorf("error while ensuring buckets exist in the database; %w", err)
 	}
 
 	return nil