feat: complete contract-driven business development and MySQL integration

middleware/contextErrors.go

@@ -0,0 +1,30 @@
+package middleware
+
+import (
+	"context"
+	"errors"
+	apierrors "git.yuntuo.hk/k2safe/go-omni/errors"
+	"git.yuntuo.hk/k2safe/go-omni/httpx"
+)
+
+// ContextErrors classifies unhandled context errors using project catalog keys.
+// Empty keys leave that class unchanged. Explicit API errors always take
+// precedence, even if they wrap a context failure. Causes stay available to logs.
+func ContextErrors(canceledKey, deadlineKey string) httpx.Middleware {
+	return func(next httpx.Handler) httpx.Handler {
+		return func(c *httpx.Context) error {
+			err := next(c)
+			var public *apierrors.APIError
+			if err == nil || errors.As(err, &public) {
+				return err
+			}
+			if canceledKey != "" && errors.Is(err, context.Canceled) {
+				return apierrors.ByCode(canceledKey).WithCause(err)
+			}
+			if deadlineKey != "" && errors.Is(err, context.DeadlineExceeded) {
+				return apierrors.ByCode(deadlineKey).WithCause(err)
+			}
+			return err
+		}
+	}
+}

middleware/contextErrors_test.go

@@ -0,0 +1,25 @@
+package middleware_test
+
+import (
+	"context"
+	"errors"
+	"fmt"
+	apierrors "git.yuntuo.hk/k2safe/go-omni/errors"
+	"git.yuntuo.hk/k2safe/go-omni/httpx"
+	"git.yuntuo.hk/k2safe/go-omni/middleware"
+	"testing"
+)
+
+func TestContextErrorsPreservesExplicitBusinessFailures(t *testing.T) {
+	business := apierrors.New(409, "CONFLICT", "conflict").WithCause(context.DeadlineExceeded)
+	for _, tc := range []struct {
+		err  error
+		code string
+	}{{context.Canceled, "CANCELED"}, {fmt.Errorf("operation: %w", context.DeadlineExceeded), "TIMEOUT"}, {business, "CONFLICT"}} {
+		err := middleware.ContextErrors("CANCELED", "TIMEOUT")(func(*httpx.Context) error { return tc.err })(nil)
+		var result *apierrors.APIError
+		if !errors.As(err, &result) || result.Code != tc.code || !errors.Is(err, tc.err) {
+			t.Fatal(err)
+		}
+	}
+}