feat: add agent-friendly ufile CLI

cmd/ufile-cli/errors.go

@@ -0,0 +1,123 @@
+package main
+
+import (
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"net"
+	"net/http"
+)
+
+type commandError struct {
+	Code       string
+	Message    string
+	HTTPStatus int
+	ExitCode   int
+	Cause      error
+}
+
+func (e *commandError) Error() string {
+	if e.Cause != nil {
+		return fmt.Sprintf("%s: %v", e.Message, e.Cause)
+	}
+	return e.Message
+}
+
+func usageError(message string) *commandError {
+	return &commandError{Code: "usage_error", Message: message, ExitCode: exitUsage}
+}
+
+func localError(message string, cause error) *commandError {
+	return &commandError{Code: "local_io_error", Message: message, ExitCode: exitLocalIO, Cause: cause}
+}
+
+func networkError(message string, cause error) *commandError {
+	return &commandError{Code: "network_error", Message: message, ExitCode: exitNetwork, Cause: cause}
+}
+
+func fromHTTPError(err *apiError) *commandError {
+	code := err.Code
+	exitCode := exitGeneral
+	switch err.Status {
+	case http.StatusBadRequest, http.StatusConflict, http.StatusUnprocessableEntity:
+		exitCode = exitValidation
+		if code == "" {
+			code = "validation_failed"
+		}
+	case http.StatusUnauthorized:
+		exitCode = exitAuth
+		if code == "" {
+			code = "authentication_required"
+		}
+	case http.StatusForbidden:
+		exitCode = exitPermission
+		if code == "" {
+			code = "permission_denied"
+		}
+	case http.StatusNotFound, http.StatusGone:
+		exitCode = exitUnavailable
+		if code == "" {
+			code = "file_unavailable"
+		}
+	default:
+		if err.Status >= 500 {
+			exitCode = exitNetwork
+		}
+	}
+	if code == "" {
+		code = "request_failed"
+	}
+	return &commandError{Code: code, Message: err.Message, HTTPStatus: err.Status, ExitCode: exitCode}
+}
+
+func classifyError(err error) *commandError {
+	if err == nil {
+		return nil
+	}
+	var commandErr *commandError
+	if errors.As(err, &commandErr) {
+		return commandErr
+	}
+	var remoteErr *apiError
+	if errors.As(err, &remoteErr) {
+		return fromHTTPError(remoteErr)
+	}
+	var netErr net.Error
+	if errors.As(err, &netErr) {
+		return networkError("请求 ufile 服务失败", err)
+	}
+	return &commandError{Code: "unexpected_error", Message: "执行失败", ExitCode: exitGeneral, Cause: err}
+}
+
+func writeCommandError(out io.Writer, err *commandError) int {
+	payload := struct {
+		Error struct {
+			Code       string `json:"code"`
+			Message    string `json:"message"`
+			HTTPStatus int    `json:"httpStatus,omitempty"`
+		} `json:"error"`
+	}{}
+	payload.Error.Code = err.Code
+	payload.Error.Message = err.Message
+	if err.Cause != nil {
+		payload.Error.Message += ": " + err.Cause.Error()
+	}
+	payload.Error.HTTPStatus = err.HTTPStatus
+	encoder := json.NewEncoder(out)
+	encoder.SetEscapeHTML(false)
+	_ = encoder.Encode(payload)
+	if err.ExitCode == 0 {
+		return exitGeneral
+	}
+	return err.ExitCode
+}
+
+func writeJSON(out io.Writer, value any) int {
+	encoder := json.NewEncoder(out)
+	encoder.SetEscapeHTML(false)
+	if err := encoder.Encode(value); err != nil {
+		return exitLocalIO
+	}
+	return exitOK
+}