Files
fn_registry/functions/infra/crud_update_handler.go
T
egutierrez 28599436e5 feat(crud): handlers HTTP y registro de rutas para recursos CRUD
Anade los 5 handlers CRUD genericos (list, get, create, update, delete) a
partir de un CRUDResource y *sql.DB, la factory crud_generate_handlers que
compone los 5 en un mapa, y crud_register_routes que registra todas las
rutas REST en un http.ServeMux con la sintaxis METHOD /path de Go 1.22+.

Caracteristicas:
- List con paginacion (page, per_page), orden (sort_by, sort_dir) y
  filtros exactos (filter_<campo>), validando nombres de columna contra
  la definicion del recurso para evitar SQL injection.
- Create valida required y validaciones (min/max, min_length/max_length,
  pattern, enum) antes de insertar; mapea UNIQUE violations a 409.
- Update hace partial update — solo los campos presentes en el JSON.
- Delete hace hard delete o soft delete segun CRUDResource.SoftDelete.
- UUIDs generados via github.com/google/uuid; timestamps en RFC3339Nano UTC.

Los handlers usan las funciones HTTP del registry (http_json_response,
http_error_response, http_parse_body) y se pueden componer con el mux
via http_router.
2026-04-18 17:15:33 +02:00

98 lines
3.3 KiB
Go

package infra
import (
"database/sql"
"fmt"
"net/http"
"strings"
"time"
)
// CRUDUpdateHandler retorna un http.HandlerFunc que hace partial update por id.
// Solo actualiza los campos presentes en el body JSON. Valida los campos enviados
// contra las reglas del recurso. 404 si no existe (o soft-deleted), 400 si falla validacion.
func CRUDUpdateHandler(res CRUDResource, db *sql.DB) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
id := r.PathValue("id")
if id == "" {
HTTPErrorResponse(w, HTTPError{Status: http.StatusBadRequest, Code: "missing_id", Message: "id path parameter is required"})
return
}
body := map[string]any{}
if err := HTTPParseBody(r, &body, 1<<20); err != nil {
HTTPErrorResponse(w, HTTPError{Status: http.StatusBadRequest, Code: "invalid_body", Message: err.Error()})
return
}
// Validar que existe
existsSQL := fmt.Sprintf("SELECT 1 FROM %s WHERE id = ?", res.Table)
if res.SoftDelete {
existsSQL += " AND deleted_at IS NULL"
}
var dummy int
if err := db.QueryRow(existsSQL, id).Scan(&dummy); err != nil {
if err == sql.ErrNoRows {
HTTPErrorResponse(w, HTTPError{Status: http.StatusNotFound, Code: "not_found", Message: fmt.Sprintf("%s %q not found", res.Name, id)})
return
}
HTTPErrorResponse(w, HTTPError{Status: http.StatusInternalServerError, Code: "db_error", Message: err.Error()})
return
}
// Validar los campos presentes
setCols := []string{}
args := []any{}
for _, f := range res.Fields {
val, present := body[f.Name]
if !present {
continue
}
if err := crudValidateField(f, val); err != nil {
HTTPErrorResponse(w, HTTPError{Status: http.StatusBadRequest, Code: "validation_error", Message: err.Error()})
return
}
setCols = append(setCols, fmt.Sprintf("%s = ?", f.Name))
args = append(args, val)
}
now := time.Now().UTC().Format(time.RFC3339Nano)
setCols = append(setCols, "updated_at = ?")
args = append(args, now)
args = append(args, id)
updateSQL := fmt.Sprintf("UPDATE %s SET %s WHERE id = ?", res.Table, strings.Join(setCols, ", "))
if _, err := db.Exec(updateSQL, args...); err != nil {
if strings.Contains(strings.ToLower(err.Error()), "unique") {
HTTPErrorResponse(w, HTTPError{Status: http.StatusConflict, Code: "unique_violation", Message: err.Error()})
return
}
HTTPErrorResponse(w, HTTPError{Status: http.StatusInternalServerError, Code: "db_error", Message: err.Error()})
return
}
// Leer de vuelta
rows, err := db.Query(fmt.Sprintf("SELECT * FROM %s WHERE id = ?", res.Table), id)
if err != nil {
HTTPErrorResponse(w, HTTPError{Status: http.StatusInternalServerError, Code: "db_error", Message: err.Error()})
return
}
defer rows.Close()
cols, err := rows.Columns()
if err != nil {
HTTPErrorResponse(w, HTTPError{Status: http.StatusInternalServerError, Code: "db_error", Message: err.Error()})
return
}
if !rows.Next() {
HTTPErrorResponse(w, HTTPError{Status: http.StatusNotFound, Code: "not_found", Message: fmt.Sprintf("%s %q not found after update", res.Name, id)})
return
}
row, err := crudScanRow(rows, cols)
if err != nil {
HTTPErrorResponse(w, HTTPError{Status: http.StatusInternalServerError, Code: "db_error", Message: err.Error()})
return
}
HTTPJSONResponse(w, http.StatusOK, row)
}
}