recipes2/internal/storage/postgresql/postgresql.go

361 lines
7.8 KiB
Go

package postgresql
import (
"context"
"fmt"
"recipes/internal/domain/models"
"github.com/jackc/pgx/v5/pgxpool"
)
type Storage struct {
db *pgxpool.Pool
}
// TODO
// handling special errors
// AddRecipeInformation
func New(ctx context.Context, user, password, addr, dbname string) (*Storage, error) {
const op = "storage.postgresql.New"
pool, err := pgxpool.New(ctx, fmt.Sprintf("postgres://%s:%s@%s/%s?sslmode=disable", user, password, addr, dbname))
if err != nil {
return nil, fmt.Errorf("%s: %w", op, err)
}
return &Storage{db: pool}, nil
}
// AddRecipe adds recipe to db.
func (s *Storage) AddRecipe(ctx context.Context, recipe models.Recipe) error {
const op = "storage.postgresql.AddRecipe"
// open transaction
tx, err := s.db.Begin(ctx)
if err != nil {
return fmt.Errorf("%s: %w", op, err)
}
// refactor error handling
// rollback transaction on return
defer tx.Rollback(ctx)
var id uint
// insert recipe
err = s.db.QueryRow(
ctx,
"insert into recipe (title, description, image, cooking_time, servings, cal) values ($1, $2, $3, $4, $5, $6) returning id",
recipe.Title, recipe.Description, recipe.Image, recipe.CookingTime, recipe.ServingsNum, recipe.Calories,
).Scan(&id)
if err != nil {
return fmt.Errorf("%s: %w", op, err)
}
// insert ingredients
for _, r := range recipe.Ingredients {
var ing_id uint
err = s.db.QueryRow(
ctx,
"insert into recipe_ingredients_group (recipe_id, title) values ($1, $2) returning id",
id, r.Title,
).Scan(&ing_id)
if err != nil {
return fmt.Errorf("%s: %w", op, err)
}
for _, i := range r.Ingredients {
_, err = s.db.Exec(
ctx,
"insert into recipe_ingredients (recipe_ingredients_group_id, ingredient) values ($1, $2)",
ing_id, i,
)
if err != nil {
return fmt.Errorf("%s: %w", op, err)
}
}
}
// insert steps
for i, step := range recipe.Recipe_steps {
_, err = s.db.Exec(
ctx,
"insert into recipe_steps (recipe_id, step_num, step_text) values ($1, $2, $3)",
id, i, step,
)
if err != nil {
return fmt.Errorf("%s: %w", op, err)
}
}
// insert advices
for _, a := range recipe.Advices {
_, err = s.db.Exec(
ctx,
"insert into recipe_advices (recipe_id, advice) values ($1, $2)",
id, a,
)
if err != nil {
return fmt.Errorf("%s: %w", op, err)
}
}
// insert categories
for _, c := range recipe.Categories {
_, err = s.db.Exec(
ctx,
"insert into recipe_categories (recipe_id, category) values ($1, $2)",
id, c,
)
if err != nil {
return fmt.Errorf("%s: %w", op, err)
}
}
// commit transaction
if err := tx.Commit(ctx); err != nil {
return fmt.Errorf("%s: %w", op, err)
}
return nil
}
// RecipeExists returns true if recipe is exists.
func (s *Storage) RecipeExists(ctx context.Context, title string) (bool, error) {
const op = "storage.postgresql.RecipeExists"
var exists bool
err := s.db.QueryRow(
ctx,
"select exists(select id from recipe where title = $1)",
title,
).Scan(&exists)
if err != nil {
return false, fmt.Errorf("%s: %w", op, err)
}
return exists, nil
}
// GetRecipes gets recipes by offset and limit.
func (s *Storage) GetRecipes(ctx context.Context, offset, limit int) ([]models.Recipe, error) {
const op = "storage.postgresql.GetRecipes"
rows, err := s.db.Query(
ctx,
"select id, title, image, cooking_time, cal from recipe order by id desc offset $1 limit $2",
offset, limit,
)
if err != nil {
return nil, fmt.Errorf("%s: %w", op, err)
}
defer rows.Close()
var recipes []models.Recipe = make([]models.Recipe, 0, limit)
for rows.Next() {
var r models.Recipe
err = rows.Scan(
&r.ID,
&r.Title,
&r.Image,
&r.CookingTime,
&r.Calories,
)
if err != nil {
return nil, fmt.Errorf("%s: %w", op, err)
}
recipes = append(recipes, r)
}
return recipes, nil
}
// GetRecipe gets recipe by id.
func (s *Storage) GetRecipe(ctx context.Context, r_id uint) (models.Recipe, error) {
const op = "storage.postgresql.GetRecipe"
var recipe models.Recipe
err := s.db.QueryRow(
ctx,
"select title, description, image, cooking_time, servings, cal from recipe where id = $1",
r_id,
).Scan(&recipe)
if err != nil {
return models.Recipe{}, fmt.Errorf("%s: %w", op, err)
}
err = s.AddRecipeInformation(ctx, &recipe)
if err != nil {
return models.Recipe{}, fmt.Errorf("%s: %w", op, err)
}
return recipe, nil
}
// AddRecipeInformation adds to recipe struct info about ingredients, steps, advices, categories.
func (s *Storage) AddRecipeInformation(ctx context.Context, r *models.Recipe) error {
const op = "storage.postgresql.AddRecipeInformation"
// select ingredients
ingredientsg_rows, err := s.db.Query(
ctx,
"select id, title from recipe_ingredients_group where recipe_id = $1",
r.ID,
)
if err != nil {
return fmt.Errorf("%s: %w", op, err)
}
defer ingredientsg_rows.Close()
for ingredientsg_rows.Next() {
var ingredients_group_id uint
var recipe_ingredients models.RecipeIngredients
err = ingredientsg_rows.Scan(
&ingredients_group_id,
&recipe_ingredients.Title,
)
if err != nil {
return fmt.Errorf("%s: %w", op, err)
}
ingredient_rows, err := s.db.Query(
ctx,
"select ingredient from recipe_ingredients where recipe_ingredients_group_id = $1",
ingredients_group_id,
)
if err != nil {
return fmt.Errorf("%s: %w", op, err)
}
defer ingredient_rows.Close()
for ingredient_rows.Next() {
var ingredient string
err = ingredient_rows.Scan(
&ingredient,
)
if err != nil {
return fmt.Errorf("%s: %w", op, err)
}
recipe_ingredients.Ingredients = append(recipe_ingredients.Ingredients, ingredient)
}
r.Ingredients = append(r.Ingredients, recipe_ingredients)
}
// select steps
step_rows, err := s.db.Query(ctx, "select step_text from recipe_steps where recipe_id = $1 order by step_num", r.ID)
if err != nil {
return fmt.Errorf("%s: %w", op, err)
}
defer step_rows.Close()
for step_rows.Next() {
var step string
err = step_rows.Scan(
&step,
)
if err != nil {
return fmt.Errorf("%s: %w", op, err)
}
r.Recipe_steps = append(r.Recipe_steps, step)
}
// select advices
advice_rows, err := s.db.Query(ctx, "select advice from recipe_advices where recipe_id = $1", r.ID)
if err != nil {
return fmt.Errorf("%s: %w", op, err)
}
defer advice_rows.Close()
for advice_rows.Next() {
var advice string
err = advice_rows.Scan(
&advice,
)
if err != nil {
return fmt.Errorf("%s: %w", op, err)
}
r.Advices = append(r.Advices, advice)
}
// select categories
category_rows, err := s.db.Query(ctx, "select category from recipe_categories where recipe_id = $1", r.ID)
if err != nil {
return fmt.Errorf("%s: %w", op, err)
}
defer category_rows.Close()
for category_rows.Next() {
var category string
err = category_rows.Scan(
&category,
)
if err != nil {
return fmt.Errorf("%s: %w", op, err)
}
r.Categories = append(r.Categories, category)
}
return nil
}
// GetRecipesByCategory gets recipes by category, offset and limit.
func (s *Storage) GetRecipesByCategory(ctx context.Context, offset, limit int, category string) ([]models.Recipe, error) {
const op = "storage.postgresql.GetRecipesByCategory"
rows, err := s.db.Query(
ctx,
"select r.id, r.title, r.image, r.cooking_time, r.cal from recipe r inner join recipe_categories c on r.id = c.recipe_id where c.category = $1 order by r.id limit $2 offset $3",
category, limit, offset,
)
if err != nil {
return nil, fmt.Errorf("%s: %w", op, err)
}
defer rows.Close()
var recipes []models.Recipe = make([]models.Recipe, 0, limit)
for rows.Next() {
var r models.Recipe
err = rows.Scan(
&r.ID,
&r.Title,
&r.Image,
&r.CookingTime,
&r.Calories,
)
if err != nil {
return nil, fmt.Errorf("%s: %w", op, err)
}
err = s.AddRecipeInformation(ctx, &r)
if err != nil {
return nil, fmt.Errorf("%s: %w", op, err)
}
recipes = append(recipes, r)
}
return recipes, nil
}