feat(errors): implemented custom errors

Signed-off-by: SoXX <soxx@fenpa.ws>

error/validation.go

@@ -1,7 +0,0 @@
-package error
-
-type MissingAnthrovePostIDError struct{}
-
-func (e *MissingAnthrovePostIDError) Error() string {
-	return "AnthrovePostID is empty"
-}

internal/postgres/post.go

@@ -3,24 +3,29 @@ package postgres
 import (
 	"context"
 	"errors"
+	errors2 "git.dragse.it/anthrove/otter-space-sdk/pkg/errors"
 
-	error2 "git.dragse.it/anthrove/otter-space-sdk/error"
 	"git.dragse.it/anthrove/otter-space-sdk/pkg/models"
 	log "github.com/sirupsen/logrus"
 	"gorm.io/gorm"
 )
 
 func CreatePost(ctx context.Context, db *gorm.DB, anthrovePost *models.Post) error {
-	result := db.WithContext(ctx).Create(&anthrovePost)
 
-	if result.RowsAffected == 0 {
-		return &error2.NoDataWritten{}
+	if anthrovePost == nil {
+		return &errors2.EntityValidationFailed{Reason: "anthrovePost is nil"}
 	}
 
+	result := db.WithContext(ctx).Create(&anthrovePost)
 	if result.Error != nil {
 		if errors.Is(result.Error, gorm.ErrDuplicatedKey) {
-			return &error2.EntityAlreadyExists{}
+			return &errors2.EntityAlreadyExists{}
 		}
+		return result.Error
+	}
+
+	if result.RowsAffected == 0 {
+		return &errors2.NoDataWritten{}
 	}
 
 	log.WithFields(log.Fields{
@@ -32,44 +37,58 @@ func CreatePost(ctx context.Context, db *gorm.DB, anthrovePost *models.Post) err
 }
 
 func GetPostByAnthroveID(ctx context.Context, db *gorm.DB, anthrovePostID models.AnthrovePostID) (*models.Post, error) {
+
 	if anthrovePostID == "" {
-		return nil, &error2.MissingAnthrovePostIDError{}
+		return nil, &errors2.EntityValidationFailed{Reason: "anthrovePostID is not set"}
 	}
 
+	//TODO maybe check ofor id length too...?
+
 	var post models.Post
 	result := db.WithContext(ctx).First(&post, "id = ?", anthrovePostID)
 	if result.Error != nil {
 		if errors.Is(result.Error, gorm.ErrRecordNotFound) {
-			return nil, &error2.NoDataFound{}
+			return nil, &errors2.NoDataFound{}
 		}
+		return nil, result.Error
 	}
 
 	return &post, nil
 }
 
 func GetPostByURL(ctx context.Context, db *gorm.DB, sourceURL string) (*models.Post, error) {
-	var post models.Post
-	err := db.WithContext(ctx).Raw(`SELECT p.id AS id, p.rating as rating FROM "Post" AS p INNER JOIN "PostReference" AS pr ON p.id = pr.post_id AND pr.url = $1 LIMIT 1`, sourceURL).First(&post).Error
 
-	if err != nil {
-		if errors.Is(err, gorm.ErrRecordNotFound) {
-			return nil, nil
+	if sourceURL == "" {
+		return nil, &errors2.EntityValidationFailed{Reason: "sourceURL is not set"}
 	}
-		return nil, err
+
+	var post models.Post
+	result := db.WithContext(ctx).Raw(`SELECT p.id AS id, p.rating as rating FROM "Post" AS p INNER JOIN "PostReference" AS pr ON p.id = pr.post_id AND pr.url = $1 LIMIT 1`, sourceURL).First(&post)
+
+	if result.Error != nil {
+		if errors.Is(result.Error, gorm.ErrRecordNotFound) {
+			return nil, &errors2.NoDataFound{}
+		}
+		return nil, result.Error
 	}
 
 	return &post, nil
 }
 
 func GetPostBySourceID(ctx context.Context, db *gorm.DB, sourceID models.AnthroveSourceID) (*models.Post, error) {
-	var post models.Post
-	err := db.WithContext(ctx).Raw(`SELECT p.id AS id, p.rating as rating FROM "Post" AS p INNER JOIN "PostReference" AS pr ON p.id = pr.post_id AND pr.source_id = $1 LIMIT 1`, sourceID).First(&post).Error
 
-	if err != nil {
-		if errors.Is(err, gorm.ErrRecordNotFound) {
-			return nil, nil
+	if sourceID == "" {
+		return nil, &errors2.EntityValidationFailed{Reason: "sourceID is not set"}
 	}
-		return nil, err
+
+	var post models.Post
+	result := db.WithContext(ctx).Raw(`SELECT p.id AS id, p.rating as rating FROM "Post" AS p INNER JOIN "PostReference" AS pr ON p.id = pr.post_id AND pr.source_id = $1 LIMIT 1`, sourceID).First(&post)
+
+	if result.Error != nil {
+		if errors.Is(result.Error, gorm.ErrRecordNotFound) {
+			return nil, &errors2.NoDataFound{}
+		}
+		return nil, result.Error
 	}
 
 	return &post, nil

internal/postgres/relationships.go

@@ -2,6 +2,8 @@ package postgres
 
 import (
 	"context"
+	"errors"
+	errors2 "git.dragse.it/anthrove/otter-space-sdk/pkg/errors"
 	"git.dragse.it/anthrove/otter-space-sdk/pkg/models"
 	log "github.com/sirupsen/logrus"
 	"gorm.io/gorm"
@@ -9,23 +11,44 @@ import (
 
 func CreateReferenceBetweenPostAndSource(ctx context.Context, db *gorm.DB, anthrovePostID models.AnthrovePostID, sourceDomain models.AnthroveSourceDomain) error {
 	var source models.Source
-	var err error
+
+	if anthrovePostID == "" {
+		return &errors2.EntityValidationFailed{Reason: "anthrovePostID cannot be empty"}
+	}
+
+	if len(anthrovePostID) != 25 {
+		return &errors2.EntityValidationFailed{Reason: "anthrovePostID needs to be 25 characters long"}
+	}
+
+	if sourceDomain == "" {
+		return &errors2.EntityValidationFailed{Reason: "sourceDomain cannot be empty"}
+	}
 
 	// Find the source
-	err = db.WithContext(ctx).Where("domain = ?", sourceDomain).First(&source).Error
-	if err != nil {
-		return err
+	result := db.WithContext(ctx).Where("domain = ?", sourceDomain).First(&source)
+	if result.Error != nil {
+		if errors.Is(result.Error, gorm.ErrRecordNotFound) {
+			return &errors2.NoDataFound{}
+		}
+		return result.Error
 	}
 
 	// Establish the relationship
-	err = db.WithContext(ctx).Create(models.PostReference{
+	result = db.WithContext(ctx).Create(models.PostReference{
 		PostID:   string(anthrovePostID),
 		SourceID: string(source.ID),
 		URL:      string(sourceDomain),
-	}).Error
+	})
 
-	if err != nil {
-		return err
+	if result.Error != nil {
+		if errors.Is(result.Error, gorm.ErrDuplicatedKey) {
+			return &errors2.EntityAlreadyExists{}
+		}
+		return result.Error
+	}
+
+	if result.RowsAffected == 0 {
+		return &errors2.NoDataWritten{}
 	}
 
 	log.WithFields(log.Fields{
@@ -37,14 +60,34 @@ func CreateReferenceBetweenPostAndSource(ctx context.Context, db *gorm.DB, anthr
 }
 
 func CreateReferenceBetweenUserAndPost(ctx context.Context, db *gorm.DB, anthroveUserID models.AnthroveUserID, anthrovePostID models.AnthrovePostID) error {
+
+	if anthrovePostID == "" {
+		return &errors2.EntityValidationFailed{Reason: "anthrovePostID cannot be empty"}
+	}
+
+	if len(anthrovePostID) != 25 {
+		return &errors2.EntityValidationFailed{Reason: "anthrovePostID needs to be 25 characters long"}
+	}
+
+	if anthroveUserID == "" {
+		return &errors2.EntityValidationFailed{Reason: "anthroveUserID cannot be empty"}
+	}
+
 	userFavorite := models.UserFavorites{
 		UserID: string(anthroveUserID),
 		PostID: string(anthrovePostID),
 	}
 
-	err := db.WithContext(ctx).Create(&userFavorite).Error
-	if err != nil {
-		return err
+	result := db.WithContext(ctx).Create(&userFavorite)
+	if result.Error != nil {
+		if errors.Is(result.Error, gorm.ErrDuplicatedKey) {
+			return &errors2.EntityAlreadyExists{}
+		}
+		return result.Error
+	}
+
+	if result.RowsAffected == 0 {
+		return &errors2.NoDataWritten{}
 	}
 
 	log.WithFields(log.Fields{
@@ -57,9 +100,25 @@ func CreateReferenceBetweenUserAndPost(ctx context.Context, db *gorm.DB, anthrov
 
 func CheckReferenceBetweenUserAndPost(ctx context.Context, db *gorm.DB, anthroveUserID models.AnthroveUserID, anthrovePostID models.AnthrovePostID) (bool, error) {
 	var count int64
-	err := db.WithContext(ctx).Model(&models.UserFavorites{}).Where("user_id = ? AND post_id = ?", string(anthroveUserID), string(anthrovePostID)).Count(&count).Error
-	if err != nil {
-		return false, err
+
+	if anthrovePostID == "" {
+		return false, &errors2.EntityValidationFailed{Reason: "anthrovePostID cannot be empty"}
+	}
+
+	if len(anthrovePostID) != 25 {
+		return false, &errors2.EntityValidationFailed{Reason: "anthrovePostID needs to be 25 characters long"}
+	}
+
+	if anthroveUserID == "" {
+		return false, &errors2.EntityValidationFailed{Reason: "anthroveUserID cannot be empty"}
+	}
+
+	result := db.WithContext(ctx).Model(&models.UserFavorites{}).Where("user_id = ? AND post_id = ?", string(anthroveUserID), string(anthrovePostID)).Count(&count)
+	if result.Error != nil {
+		if errors.Is(result.Error, gorm.ErrRecordNotFound) {
+			return false, &errors2.NoDataFound{}
+		}
+		return false, result.Error
 	}
 
 	exists := count > 0

internal/postgres/source.go

@@ -2,7 +2,8 @@ package postgres
 
 import (
 	"context"
-	"fmt"
+	"errors"
+	errors2 "git.dragse.it/anthrove/otter-space-sdk/pkg/errors"
 	"git.dragse.it/anthrove/otter-space-sdk/pkg/models"
 
 	log "github.com/sirupsen/logrus"
@@ -13,15 +14,22 @@ import (
 func CreateSource(ctx context.Context, db *gorm.DB, anthroveSource *models.Source) error {
 
 	if anthroveSource.Domain == "" {
-		return fmt.Errorf("anthroveSource domain is required")
+		return &errors2.EntityValidationFailed{Reason: "Domain is required"}
 	}
 
 	result := db.WithContext(ctx).Where(models.Source{Domain: anthroveSource.Domain}).FirstOrCreate(anthroveSource)
 
 	if result.Error != nil {
+		if errors.Is(result.Error, gorm.ErrDuplicatedKey) {
+			return &errors2.EntityAlreadyExists{}
+		}
 		return result.Error
 	}
 
+	if result.RowsAffected == 0 {
+		return &errors2.NoDataWritten{}
+	}
+
 	log.WithFields(log.Fields{
 		"node_source_url":         anthroveSource.Domain,
 		"node_source_displayName": anthroveSource.DisplayName,
@@ -38,6 +46,9 @@ func GetAllSource(ctx context.Context, db *gorm.DB) ([]models.Source, error) {
 	result := db.WithContext(ctx).Find(&sources)
 
 	if result.Error != nil {
+		if errors.Is(result.Error, gorm.ErrRecordNotFound) {
+			return nil, &errors2.NoDataFound{}
+		} // TODO  really...? i don't think this error handling should be here..? / not possible
 		return nil, result.Error
 	}
 
@@ -53,12 +64,15 @@ func GetSourceByDomain(ctx context.Context, db *gorm.DB, sourceDomain models.Ant
 	var sources models.Source
 
 	if sourceDomain == "" {
-		return nil, fmt.Errorf("domain is required")
+		return nil, &errors2.EntityValidationFailed{Reason: "AnthroveSourceDomain is not set"}
 	}
 
 	result := db.WithContext(ctx).Where("domain = ?", sourceDomain).First(&sources)
 
 	if result.Error != nil {
+		if errors.Is(result.Error, gorm.ErrRecordNotFound) {
+			return nil, &errors2.NoDataFound{}
+		}
 		return nil, result.Error
 	}
 

internal/postgres/tag.go

@@ -2,7 +2,8 @@ package postgres
 
 import (
 	"context"
-	"fmt"
+	"errors"
+	errors2 "git.dragse.it/anthrove/otter-space-sdk/pkg/errors"
 	"git.dragse.it/anthrove/otter-space-sdk/pkg/models"
 	log "github.com/sirupsen/logrus"
 	"gorm.io/gorm"
@@ -10,10 +11,20 @@ import (
 
 func CreateTag(ctx context.Context, db *gorm.DB, tag *models.Tag) error {
 
-	resultTag := db.WithContext(ctx).Where(tag).Create(tag)
+	if tag == nil {
+		return &errors2.EntityValidationFailed{Reason: "Tag is nil"}
+	}
 
-	if resultTag.Error != nil {
-		return resultTag.Error
+	result := db.WithContext(ctx).Where(tag).Create(tag)
+	if result.Error != nil {
+		if errors.Is(result.Error, gorm.ErrDuplicatedKey) {
+			return &errors2.EntityAlreadyExists{}
+		}
+		return result.Error
+	}
+
+	if result.RowsAffected == 0 {
+		return &errors2.NoDataWritten{}
 	}
 
 	log.WithFields(log.Fields{
@@ -24,30 +35,36 @@ func CreateTag(ctx context.Context, db *gorm.DB, tag *models.Tag) error {
 	return nil
 }
 
-func CreateTagAndReferenceToPost(ctx context.Context, db *gorm.DB, PostID models.AnthrovePostID, tag *models.Tag) error {
+func CreateTagAndReferenceToPost(ctx context.Context, db *gorm.DB, anthrovePostID models.AnthrovePostID, tag *models.Tag) error {
 
-	if PostID == "" {
-		return fmt.Errorf("PostID is empty")
+	if anthrovePostID == "" {
+		return &errors2.EntityValidationFailed{Reason: "anthrovePostID cannot be empty"}
+	}
+
+	if len(anthrovePostID) != 25 {
+		return &errors2.EntityValidationFailed{Reason: "anthrovePostID needs to be 25 characters long"}
 	}
 
 	if tag == nil {
-		return fmt.Errorf("tag is nill")
+		return &errors2.EntityValidationFailed{Reason: "Tag is nil"}
 	}
 
 	pgPost := models.Post{
 		BaseModel: models.BaseModel[models.AnthrovePostID]{
-			ID: PostID,
+			ID: anthrovePostID,
 		},
 	}
 
 	err := db.WithContext(ctx).Model(&pgPost).Association("Tags").Append(tag)
-
 	if err != nil {
-		return err
+		if errors.Is(err, gorm.ErrRecordNotFound) {
+			return &errors2.NoDataFound{}
+		}
+		return errors.Join(err, &errors2.NoRelationCreated{})
 	}
 
 	log.WithFields(log.Fields{
-		"anthrove_post_id": PostID,
+		"anthrove_post_id": anthrovePostID,
 		"tag_name":         tag.Name,
 		"tag_type":         tag.Type,
 	}).Trace("database: created tag node")
@@ -57,8 +74,13 @@ func CreateTagAndReferenceToPost(ctx context.Context, db *gorm.DB, PostID models
 
 func GetTags(ctx context.Context, db *gorm.DB) ([]models.Tag, error) {
 	var tags []models.Tag
+
 	result := db.WithContext(ctx).Find(&tags)
+
 	if result.Error != nil {
+		if errors.Is(result.Error, gorm.ErrRecordNotFound) { // TODO  really...? i don't think this error handling should be here..? / not possible
+			return nil, &errors2.NoDataFound{}
+		}
 		return nil, result.Error
 	}
 

internal/postgres/user.go

@@ -2,7 +2,8 @@ package postgres
 
 import (
 	"context"
-	"fmt"
+	"errors"
+	errors2 "git.dragse.it/anthrove/otter-space-sdk/pkg/errors"
 	"git.dragse.it/anthrove/otter-space-sdk/pkg/models"
 	log "github.com/sirupsen/logrus"
 	"gorm.io/gorm"
@@ -11,7 +12,11 @@ import (
 func CreateUser(ctx context.Context, db *gorm.DB, anthroveUserID models.AnthroveUserID) error {
 
 	if anthroveUserID == "" {
-		return fmt.Errorf("anthroveUserID cannot be empty")
+		return &errors2.EntityValidationFailed{Reason: "anthroveUserID cannot be empty"}
+	}
+
+	if len(anthroveUserID) != 25 {
+		return &errors2.EntityValidationFailed{Reason: "anthroveUserID needs to be 25 characters long"}
 	}
 
 	user := models.User{
@@ -20,12 +25,16 @@ func CreateUser(ctx context.Context, db *gorm.DB, anthroveUserID models.Anthrove
 		},
 	}
 
-	err := db.WithContext(ctx).FirstOrCreate(&user).Error
-	if err != nil {
-		log.WithFields(log.Fields{
-			"anthrove_user_id": anthroveUserID,
-		}).Error("database: failed to create user")
-		return err
+	result := db.WithContext(ctx).FirstOrCreate(&user)
+	if result.Error != nil {
+		if errors.Is(result.Error, gorm.ErrDuplicatedKey) {
+			return &errors2.EntityAlreadyExists{}
+		}
+		return result.Error
+	}
+
+	if result.RowsAffected == 0 {
+		return &errors2.NoDataWritten{}
 	}
 
 	return nil
@@ -34,15 +43,19 @@ func CreateUser(ctx context.Context, db *gorm.DB, anthroveUserID models.Anthrove
 func CreateUserWithRelationToSource(ctx context.Context, db *gorm.DB, anthroveUserID models.AnthroveUserID, sourceID models.AnthroveSourceID, accountId string, accountUsername string) error {
 
 	if anthroveUserID == "" {
-		return fmt.Errorf("anthroveUserID cannot be empty")
+		return &errors2.EntityValidationFailed{Reason: "anthroveUserID cannot be empty"}
+	}
+
+	if len(anthroveUserID) != 25 {
+		return &errors2.EntityValidationFailed{Reason: "anthroveUserID needs to be 25 characters long"}
 	}
 
 	if accountId == "" {
-		return fmt.Errorf("account_id cannot be empty")
+		return &errors2.EntityValidationFailed{Reason: "accountID cannot be empty"}
 	}
 
 	if accountUsername == "" {
-		return fmt.Errorf("account_username cannot be empty")
+		return &errors2.EntityValidationFailed{Reason: "accountUsername cannot be empty"}
 	}
 
 	err := CreateUser(ctx, db, anthroveUserID)
@@ -54,11 +67,12 @@ func CreateUserWithRelationToSource(ctx context.Context, db *gorm.DB, anthroveUs
 		BaseModel: models.BaseModel[models.AnthroveSourceID]{ID: sourceID},
 	}
 
-	if err := db.WithContext(ctx).Where(&source).First(&source).Error; err != nil {
-		log.WithFields(log.Fields{
-			"source_id": sourceID,
-		}).Error("database: failed to find source")
-		return err
+	result := db.WithContext(ctx).Where(&source).First(&source)
+	if result.Error != nil {
+		if errors.Is(result.Error, gorm.ErrRecordNotFound) {
+			return &errors2.NoDataFound{}
+		}
+		return result.Error
 	}
 
 	userSource := models.UserSource{
@@ -69,14 +83,13 @@ func CreateUserWithRelationToSource(ctx context.Context, db *gorm.DB, anthroveUs
 		UserID:          string(anthroveUserID),
 	}
 
-	if err := db.WithContext(ctx).FirstOrCreate(&userSource).Error; err != nil {
-		log.WithFields(log.Fields{
-			"anthrove_user_id": anthroveUserID,
-			"source_id":        sourceID,
-			"account_username": accountUsername,
-			"account_id":       accountId,
-		}).Error("database: failed to create user-source relationship")
-		return err
+	result = db.WithContext(ctx).FirstOrCreate(&userSource)
+	if result.Error != nil {
+		return errors.Join(result.Error, &errors2.NoRelationCreated{})
+	}
+
+	if result.RowsAffected == 0 {
+		return &errors2.NoDataWritten{}
 	}
 
 	log.WithFields(log.Fields{
@@ -90,17 +103,22 @@ func CreateUserWithRelationToSource(ctx context.Context, db *gorm.DB, anthroveUs
 }
 
 func GetUserFavoritesCount(ctx context.Context, db *gorm.DB, anthroveUserID models.AnthroveUserID) (int64, error) {
+	var count int64
+
 	if anthroveUserID == "" {
-		return 0, fmt.Errorf("anthroveUserID cannot be empty")
+		return 0, &errors2.EntityValidationFailed{Reason: "anthroveUserID cannot be empty"}
 	}
 
-	var count int64
-	err := db.WithContext(ctx).Model(&models.UserFavorites{}).Where("user_id = ?", string(anthroveUserID)).Count(&count).Error
-	if err != nil {
-		log.WithFields(log.Fields{
-			"anthrove_user_id": anthroveUserID,
-		}).Error("database: failed to get user favorites count")
-		return 0, err
+	if len(anthroveUserID) != 25 {
+		return 0, &errors2.EntityValidationFailed{Reason: "anthroveUserID needs to be 25 characters long"}
+	}
+
+	result := db.WithContext(ctx).Model(&models.UserFavorites{}).Where("user_id = ?", string(anthroveUserID)).Count(&count)
+	if result.Error != nil {
+		if errors.Is(result.Error, gorm.ErrRecordNotFound) {
+			return 0, &errors2.NoDataFound{}
+		}
+		return 0, result.Error
 	}
 
 	log.WithFields(log.Fields{
@@ -115,22 +133,30 @@ func GetUserSourceLinks(ctx context.Context, db *gorm.DB, anthroveUserID models.
 	var userSources []models.UserSource
 	userSourceMap := make(map[string]models.UserSource)
 
-	err := db.WithContext(ctx).Model(&models.UserSource{}).Where("user_id = ?", string(anthroveUserID)).Find(&userSources).Error
-	if err != nil {
-		log.WithFields(log.Fields{
-			"anthrove_user_id": anthroveUserID,
-		}).Error("database: failed to get user source link")
-		return nil, err
+	if anthroveUserID == "" {
+		return nil, &errors2.EntityValidationFailed{Reason: "anthroveUserID cannot be empty"}
+	}
+
+	if len(anthroveUserID) != 25 {
+		return nil, &errors2.EntityValidationFailed{Reason: "anthroveUserID needs to be 25 characters long"}
+	}
+
+	result := db.WithContext(ctx).Model(&models.UserSource{}).Where("user_id = ?", string(anthroveUserID)).Find(&userSources)
+	if result.Error != nil {
+		if errors.Is(result.Error, gorm.ErrRecordNotFound) {
+			return nil, &errors2.NoDataFound{}
+		}
+		return nil, result.Error
 	}
 
 	for _, userSource := range userSources {
 		var source models.Source
-		err = db.WithContext(ctx).Model(&models.Source{}).Where("id = ?", userSource.SourceID).First(&source).Error
-		if err != nil {
-			log.WithFields(log.Fields{
-				"source_id": userSource.SourceID,
-			}).Error("database: failed to get source")
-			return nil, err
+		result = db.WithContext(ctx).Model(&models.Source{}).Where("id = ?", userSource.SourceID).First(&source)
+		if result.Error != nil {
+			if errors.Is(result.Error, gorm.ErrRecordNotFound) {
+				return nil, &errors2.NoDataFound{}
+			}
+			return nil, result.Error
 		}
 
 		userSourceMap[source.DisplayName] = models.UserSource{
@@ -152,34 +178,41 @@ func GetUserSourceLinks(ctx context.Context, db *gorm.DB, anthroveUserID models.
 }
 
 func GetUserSourceBySourceID(ctx context.Context, db *gorm.DB, anthroveUserID models.AnthroveUserID, sourceID models.AnthroveSourceID) (map[string]models.UserSource, error) {
-	if anthroveUserID == "" {
-		return nil, fmt.Errorf("anthroveUserID cannot be empty")
-	}
-
-	if sourceID == "" {
-		return nil, fmt.Errorf("sourceID cannot be empty")
-	}
-
 	var userSources []models.UserSource
 	userSourceMap := make(map[string]models.UserSource)
 
-	err := db.WithContext(ctx).Model(&models.UserSource{}).InnerJoins("Source", db.Where("id = ?", sourceID)).Where("user_id = ?", string(anthroveUserID)).First(&userSources).Error
-	if err != nil {
-		log.WithFields(log.Fields{
-			"anthrove_user_id": anthroveUserID,
-			"source_id":        sourceID,
-		}).Error("database: failed to get specified user source link")
-		return nil, err
+	if anthroveUserID == "" {
+		return nil, &errors2.EntityValidationFailed{Reason: "anthroveUserID cannot be empty"}
+	}
+
+	if len(anthroveUserID) != 25 {
+		return nil, &errors2.EntityValidationFailed{Reason: "anthroveUserID needs to be 25 characters long"}
+	}
+
+	if sourceID == "" {
+		return nil, &errors2.EntityValidationFailed{Reason: "sourceID cannot be empty"}
+	}
+
+	if len(sourceID) != 25 {
+		return nil, &errors2.EntityValidationFailed{Reason: "sourceID needs to be 25 characters long"}
+	}
+
+	result := db.WithContext(ctx).Model(&models.UserSource{}).InnerJoins("Source", db.Where("id = ?", sourceID)).Where("user_id = ?", string(anthroveUserID)).First(&userSources)
+	if result.Error != nil {
+		if errors.Is(result.Error, gorm.ErrRecordNotFound) {
+			return nil, &errors2.NoDataFound{}
+		}
+		return nil, result.Error
 	}
 
 	for _, userSource := range userSources {
 		var source models.Source
-		err = db.WithContext(ctx).Model(&models.Source{}).Where("id = ?", userSource.SourceID).First(&source).Error
-		if err != nil {
-			log.WithFields(log.Fields{
-				"source_id": userSource.SourceID,
-			}).Error("database: failed to get source")
-			return nil, err
+		result = db.WithContext(ctx).Model(&models.Source{}).Where("id = ?", userSource.SourceID).First(&source)
+		if result.Error != nil {
+			if errors.Is(result.Error, gorm.ErrRecordNotFound) {
+				return nil, &errors2.NoDataFound{}
+			}
+			return nil, result.Error
 		}
 
 		userSourceMap[source.DisplayName] = models.UserSource{
@@ -205,14 +238,16 @@ func GetAllAnthroveUserIDs(ctx context.Context, db *gorm.DB) ([]models.AnthroveU
 	var users []models.User
 	var userIDs []models.AnthroveUserID
 
-	err := db.WithContext(ctx).Model(&models.User{}).Find(&users).Error
-	if err != nil {
-		log.Error("database: failed to get all anthrove user IDs")
-		return nil, err
+	result := db.WithContext(ctx).Model(&models.User{}).Find(&users)
+	if result.Error != nil {
+		if errors.Is(result.Error, gorm.ErrRecordNotFound) {
+			return nil, &errors2.NoDataFound{}
+		}
+		return nil, result.Error
 	}
 
 	for _, user := range users {
-		userIDs = append(userIDs, models.AnthroveUserID(user.ID))
+		userIDs = append(userIDs, user.ID)
 	}
 
 	log.WithFields(log.Fields{
@@ -226,13 +261,19 @@ func GetUserFavoriteWithPagination(ctx context.Context, db *gorm.DB, anthroveUse
 	var userFavorites []models.UserFavorites
 	var favoritePosts []models.Post
 
+	if anthroveUserID == "" {
+		return nil, &errors2.EntityValidationFailed{Reason: "anthroveUserID cannot be empty"}
+	}
+
+	if len(anthroveUserID) != 25 {
+		return nil, &errors2.EntityValidationFailed{Reason: "anthroveUserID needs to be 25 characters long"}
+	}
+
 	err := db.WithContext(ctx).Model(&models.UserFavorites{}).Where("user_id = ?", string(anthroveUserID)).Offset(skip).Limit(limit).Find(&userFavorites).Error
 	if err != nil {
-		log.WithFields(log.Fields{
-			"anthrove_user_id": anthroveUserID,
-			"skip":             skip,
-			"limit":            limit,
-		}).Error("database: failed to get user favorites with pagination")
+		if errors.Is(err, gorm.ErrRecordNotFound) {
+			return nil, &errors2.NoDataFound{}
+		}
 		return nil, err
 	}
 
@@ -240,9 +281,9 @@ func GetUserFavoriteWithPagination(ctx context.Context, db *gorm.DB, anthroveUse
 		var post models.Post
 		err = db.WithContext(ctx).Model(&models.Post{}).Where("id = ?", userFavorite.PostID).First(&post).Error
 		if err != nil {
-			log.WithFields(log.Fields{
-				"post_id": userFavorite.PostID,
-			}).Error("database: failed to get post")
+			if errors.Is(err, gorm.ErrRecordNotFound) {
+				return nil, &errors2.NoDataFound{}
+			}
 			return nil, err
 		}
 
@@ -263,12 +304,21 @@ func GetUserFavoriteWithPagination(ctx context.Context, db *gorm.DB, anthroveUse
 
 func GetUserTagWitRelationToFavedPosts(ctx context.Context, db *gorm.DB, anthroveUserID models.AnthroveUserID) ([]models.TagsWithFrequency, error) {
 	var userFavorites []models.UserFavorites
-	err := db.WithContext(ctx).Where("user_id = ?", string(anthroveUserID)).Find(&userFavorites).Error
-	if err != nil {
-		log.WithFields(log.Fields{
-			"anthrove_user_id": anthroveUserID,
-		}).Error("database: failed to get user favorites")
-		return nil, err
+
+	if anthroveUserID == "" {
+		return nil, &errors2.EntityValidationFailed{Reason: "anthroveUserID cannot be empty"}
+	}
+
+	if len(anthroveUserID) != 25 {
+		return nil, &errors2.EntityValidationFailed{Reason: "anthroveUserID needs to be 25 characters long"}
+	}
+
+	result := db.WithContext(ctx).Where("user_id = ?", string(anthroveUserID)).Find(&userFavorites)
+	if result.Error != nil {
+		if errors.Is(result.Error, gorm.ErrRecordNotFound) {
+			return nil, &errors2.NoDataFound{}
+		}
+		return nil, result.Error
 	}
 
 	tagFrequency := make(map[struct {
@@ -278,12 +328,12 @@ func GetUserTagWitRelationToFavedPosts(ctx context.Context, db *gorm.DB, anthrov
 
 	for _, userFavorite := range userFavorites {
 		var post models.Post
-		err = db.WithContext(ctx).Preload("Tags").First(&post, "id = ?", userFavorite.PostID).Error
-		if err != nil {
-			log.WithFields(log.Fields{
-				"post_id": userFavorite.PostID,
-			}).Error("database: failed to get post tags")
-			return nil, err
+		result = db.WithContext(ctx).Preload("Tags").First(&post, "id = ?", userFavorite.PostID)
+		if result.Error != nil {
+			if errors.Is(result.Error, gorm.ErrRecordNotFound) {
+				return nil, &errors2.NoDataFound{}
+			}
+			return nil, result.Error
 		}
 
 		for _, tag := range post.Tags {

pkg/errors/database.go

@@ -1,19 +1,25 @@
-package error
+package errors
 
 type EntityAlreadyExists struct{}
 
-type NoDataWritten struct{}
-
-type NoDataFound struct{}
-
 func (e *EntityAlreadyExists) Error() string {
 	return "EntityAlreadyExists error"
 }
 
+type NoDataWritten struct{}
+
 func (e *NoDataWritten) Error() string {
 	return "NoDataWritten error"
 }
 
+type NoDataFound struct{}
+
 func (e *NoDataFound) Error() string {
 	return "NoDataFound error"
 }
+
+type NoRelationCreated struct{}
+
+func (e *NoRelationCreated) Error() string {
+	return "relationship creation error"
+}

pkg/errors/validation.go

@@ -0,0 +1,11 @@
+package errors
+
+import "fmt"
+
+type EntityValidationFailed struct {
+	Reason string
+}
+
+func (e EntityValidationFailed) Error() string {
+	return fmt.Sprintf("Entity validation failed: %s", e.Reason)
+}