basics

internal/usernotes/store_postgres.go

@@ -0,0 +1,93 @@
+package usernotes
+
+import (
+	"context"
+
+	"github.com/Masterminds/squirrel"
+	"github.com/bnkamalesh/errors"
+	"github.com/bnkamalesh/goapp/internal/users"
+	"github.com/google/uuid"
+	"github.com/jackc/pgx/v5/pgxpool"
+)
+
+type pgstore struct {
+	qbuilder  squirrel.StatementBuilderType
+	pqdriver  *pgxpool.Pool
+	tableName string
+}
+
+func (ps *pgstore) GetNoteByID(ctx context.Context, userID string, noteID string) (*Note, error) {
+	query, args, err := ps.qbuilder.Select(
+		"id",
+		"title",
+		"content",
+	).From(
+		ps.tableName,
+	).Where(
+		squirrel.Eq{
+			"id":      noteID,
+			"user_id": userID,
+		},
+	).ToSql()
+	if err != nil {
+		return nil, errors.Wrap(err, "failed preparing query")
+	}
+
+	usernote := &Note{
+		Creator: &users.User{
+			ID: userID,
+		},
+	}
+
+	err = ps.pqdriver.QueryRow(
+		ctx, query, args...,
+	).Scan(
+		usernote.ID,
+		usernote.Title,
+		usernote.Content,
+	)
+	if err != nil {
+		return nil, errors.Wrap(err, "failed getting user note")
+	}
+
+	return usernote, nil
+}
+
+func (ps *pgstore) SaveNote(ctx context.Context, note *Note) (string, error) {
+	noteID := ps.newNoteID()
+	query, args, err := ps.qbuilder.Insert(
+		ps.tableName,
+	).Columns(
+		"id",
+		"title",
+		"content",
+		"user_id",
+	).Values(
+		note.ID,
+		note.Title,
+		note.Content,
+		note.Creator.ID,
+	).ToSql()
+	if err != nil {
+		return "", errors.Wrap(err, "failed preparing query")
+	}
+
+	_, err = ps.pqdriver.Exec(ctx, query, args...)
+	if err != nil {
+		return "", errors.Wrap(err, "failed storing note")
+	}
+
+	return noteID, nil
+}
+
+func (ps *pgstore) newNoteID() string {
+	return uuid.New().String()
+}
+
+func NewPostgresStore(pqdriver *pgxpool.Pool, tableName string) store {
+	return &pgstore{
+		qbuilder:  squirrel.StatementBuilder.PlaceholderFormat(squirrel.Dollar),
+		pqdriver:  pqdriver,
+		tableName: tableName,
+	}
+}

internal/usernotes/usernotes.go

@@ -0,0 +1,81 @@
+// Package usernotes maintains notes of a user
+package usernotes
+
+import (
+	"context"
+	"strings"
+	"time"
+
+	"github.com/bnkamalesh/errors"
+	"github.com/bnkamalesh/goapp/internal/users"
+)
+
+type Note struct {
+	ID        string
+	Title     string
+	Content   string
+	Creator   *users.User
+	CreatedAt time.Time
+	UpdatedAt time.Time
+}
+
+func (note *Note) ValidateForCreate() error {
+	if note == nil {
+		return errors.Validation("empty note")
+	}
+
+	note.Sanitize()
+	if note.Title == "" {
+		return errors.Validation("note title cannot be empty")
+	}
+
+	if note.Content == "" {
+		return errors.Validation("note content cannot be empty")
+	}
+
+	if note.Creator == nil || note.Creator.ID == "" {
+		return errors.Validation("note creator cannot be anonymous")
+	}
+
+	return nil
+}
+
+func (note *Note) Sanitize() {
+	note.Title = strings.TrimSpace(note.Title)
+	note.Content = strings.TrimSpace(note.Content)
+}
+
+type store interface {
+	GetNoteByID(ctx context.Context, userID string, noteID string) (*Note, error)
+	SaveNote(ctx context.Context, note *Note) (string, error)
+}
+
+type UserNotes struct {
+	store store
+}
+
+func (un *UserNotes) SaveNote(ctx context.Context, note *Note) (*Note, error) {
+	err := note.ValidateForCreate()
+	if err != nil {
+		return nil, err
+	}
+
+	note.CreatedAt = time.Now()
+	note.UpdatedAt = time.Now()
+	note.ID, err = un.store.SaveNote(ctx, note)
+	if err != nil {
+		return nil, err
+	}
+
+	return note, nil
+}
+
+func (un *UserNotes) GetNoteByID(ctx context.Context, userID string, noteID string) (*Note, error) {
+	return un.store.GetNoteByID(ctx, userID, noteID)
+}
+
+func NewService(store store) *UserNotes {
+	return &UserNotes{
+		store: store,
+	}
+}