Files
fn_registry/functions/infra/crud_create_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

93 lines
3.1 KiB
Go

package infra
import (
"database/sql"
"fmt"
"net/http"
"strings"
"time"
"github.com/google/uuid"
)
// CRUDCreateHandler retorna un http.HandlerFunc que parsea un body JSON,
// valida los campos contra la definicion del recurso, genera id UUID y timestamps,
// inserta en la tabla y responde 201 con el registro creado.
func CRUDCreateHandler(res CRUDResource, db *sql.DB) http.HandlerFunc {
return func(w http.ResponseWriter, r *http.Request) {
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 campos required y validaciones
for _, f := range res.Fields {
val, present := body[f.Name]
if !present {
if f.Required && f.Default == "" {
HTTPErrorResponse(w, HTTPError{Status: http.StatusBadRequest, Code: "validation_error", Message: fmt.Sprintf("field %q is required", f.Name)})
return
}
continue
}
if err := crudValidateField(f, val); err != nil {
HTTPErrorResponse(w, HTTPError{Status: http.StatusBadRequest, Code: "validation_error", Message: err.Error()})
return
}
}
id := uuid.NewString()
now := time.Now().UTC().Format(time.RFC3339Nano)
// Construir INSERT solo con los campos presentes
cols := []string{"id"}
placeholders := []string{"?"}
args := []any{id}
for _, f := range res.Fields {
if val, present := body[f.Name]; present {
cols = append(cols, f.Name)
placeholders = append(placeholders, "?")
args = append(args, val)
}
}
cols = append(cols, "created_at", "updated_at")
placeholders = append(placeholders, "?", "?")
args = append(args, now, now)
insertSQL := fmt.Sprintf("INSERT INTO %s (%s) VALUES (%s)", res.Table, strings.Join(cols, ", "), strings.Join(placeholders, ", "))
if _, err := db.Exec(insertSQL, args...); err != nil {
// UNIQUE violations → 409
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 para devolver todas las columnas (incluido defaults)
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()
colsOut, 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.StatusInternalServerError, Code: "db_error", Message: "inserted row not found"})
return
}
row, err := crudScanRow(rows, colsOut)
if err != nil {
HTTPErrorResponse(w, HTTPError{Status: http.StatusInternalServerError, Code: "db_error", Message: err.Error()})
return
}
HTTPJSONResponse(w, http.StatusCreated, row)
}
}