github.com/cloudwego/kitex@v0.9.0/pkg/remote/trans/nphttp2/status/status.go (about)

     1  /*
     2   *
     3   * Copyright 2020 gRPC authors.
     4   *
     5   * Licensed under the Apache License, Version 2.0 (the "License");
     6   * you may not use this file except in compliance with the License.
     7   * You may obtain a copy of the License at
     8   *
     9   *     http://www.apache.org/licenses/LICENSE-2.0
    10   *
    11   * Unless required by applicable law or agreed to in writing, software
    12   * distributed under the License is distributed on an "AS IS" BASIS,
    13   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    14   * See the License for the specific language governing permissions and
    15   * limitations under the License.
    16   *
    17   * This file may have been modified by CloudWeGo authors. All CloudWeGo
    18   * Modifications are Copyright 2021 CloudWeGo Authors.
    19   */
    20  
    21  // Package status implements errors returned by gRPC. These errors are
    22  // serialized and transmitted on the wire between server and client, and allow
    23  // for additional data to be transmitted via the Details field in the status
    24  // proto. gRPC service handlers should return an error created by this
    25  // package, and gRPC clients should expect a corresponding error to be
    26  // returned from the RPC call.
    27  //
    28  // This package upholds the invariants that a non-nil error may not
    29  // contain an OK code, and an OK code must result in a nil error.
    30  package status
    31  
    32  import (
    33  	"context"
    34  	"errors"
    35  	"fmt"
    36  
    37  	spb "google.golang.org/genproto/googleapis/rpc/status"
    38  	"google.golang.org/protobuf/proto"
    39  	"google.golang.org/protobuf/types/known/anypb"
    40  
    41  	"github.com/cloudwego/kitex/pkg/remote/trans/nphttp2/codes"
    42  )
    43  
    44  type Iface interface {
    45  	GRPCStatus() *Status
    46  }
    47  
    48  // Status represents an RPC status code, message, and details.  It is immutable
    49  // and should be created with New, Newf, or FromProto.
    50  type Status struct {
    51  	s *spb.Status
    52  }
    53  
    54  // New returns a Status representing c and msg.
    55  func New(c codes.Code, msg string) *Status {
    56  	return &Status{s: &spb.Status{Code: int32(c), Message: msg}}
    57  }
    58  
    59  // Newf returns New(c, fmt.Sprintf(format, a...)).
    60  func Newf(c codes.Code, format string, a ...interface{}) *Status {
    61  	return New(c, fmt.Sprintf(format, a...))
    62  }
    63  
    64  // ErrorProto returns an error representing s.  If s.Code is OK, returns nil.
    65  func ErrorProto(s *spb.Status) error {
    66  	return FromProto(s).Err()
    67  }
    68  
    69  // FromProto returns a Status representing s.
    70  func FromProto(s *spb.Status) *Status {
    71  	return &Status{s: proto.Clone(s).(*spb.Status)}
    72  }
    73  
    74  // Err returns an error representing c and msg.  If c is OK, returns nil.
    75  func Err(c codes.Code, msg string) error {
    76  	return New(c, msg).Err()
    77  }
    78  
    79  // Errorf returns Error(c, fmt.Sprintf(format, a...)).
    80  func Errorf(c codes.Code, format string, a ...interface{}) error {
    81  	return Err(c, fmt.Sprintf(format, a...))
    82  }
    83  
    84  // Code returns the status code contained in s.
    85  func (s *Status) Code() codes.Code {
    86  	if s == nil || s.s == nil {
    87  		return codes.OK
    88  	}
    89  	return codes.Code(s.s.Code)
    90  }
    91  
    92  // Message returns the message contained in s.
    93  func (s *Status) Message() string {
    94  	if s == nil || s.s == nil {
    95  		return ""
    96  	}
    97  	return s.s.Message
    98  }
    99  
   100  // AppendMessage append extra msg for Status
   101  func (s *Status) AppendMessage(extraMsg string) *Status {
   102  	if s == nil || s.s == nil || extraMsg == "" {
   103  		return s
   104  	}
   105  	s.s.Message = fmt.Sprintf("%s %s", s.s.Message, extraMsg)
   106  	return s
   107  }
   108  
   109  // Proto returns s's status as an spb.Status proto message.
   110  func (s *Status) Proto() *spb.Status {
   111  	if s == nil {
   112  		return nil
   113  	}
   114  	return proto.Clone(s.s).(*spb.Status)
   115  }
   116  
   117  // Err returns an immutable error representing s; returns nil if s.Code() is OK.
   118  func (s *Status) Err() error {
   119  	if s.Code() == codes.OK {
   120  		return nil
   121  	}
   122  	return &Error{e: s.Proto()}
   123  }
   124  
   125  // WithDetails returns a new status with the provided details messages appended to the status.
   126  // If any errors are encountered, it returns nil and the first error encountered.
   127  func (s *Status) WithDetails(details ...proto.Message) (*Status, error) {
   128  	if s.Code() == codes.OK {
   129  		return nil, errors.New("no error details for status with code OK")
   130  	}
   131  	// s.Code() != OK implies that s.Proto() != nil.
   132  	p := s.Proto()
   133  	for _, detail := range details {
   134  		any, err := anypb.New(detail)
   135  		if err != nil {
   136  			return nil, err
   137  		}
   138  		p.Details = append(p.Details, any)
   139  	}
   140  	return &Status{s: p}, nil
   141  }
   142  
   143  // Details returns a slice of details messages attached to the status.
   144  // If a detail cannot be decoded, the error is returned in place of the detail.
   145  func (s *Status) Details() []interface{} {
   146  	if s == nil || s.s == nil {
   147  		return nil
   148  	}
   149  	details := make([]interface{}, 0, len(s.s.Details))
   150  	for _, any := range s.s.Details {
   151  		detail, err := any.UnmarshalNew()
   152  		if err != nil {
   153  			details = append(details, err)
   154  			continue
   155  		}
   156  		details = append(details, detail)
   157  	}
   158  	return details
   159  }
   160  
   161  // Error wraps a pointer of a status proto. It implements error and Status,
   162  // and a nil *Error should never be returned by this package.
   163  type Error struct {
   164  	e *spb.Status
   165  }
   166  
   167  func (e *Error) Error() string {
   168  	return fmt.Sprintf("rpc error: code = %d desc = %s", codes.Code(e.e.GetCode()), e.e.GetMessage())
   169  }
   170  
   171  // GRPCStatus returns the Status represented by se.
   172  func (e *Error) GRPCStatus() *Status {
   173  	return FromProto(e.e)
   174  }
   175  
   176  // Is implements future error.Is functionality.
   177  // A Error is equivalent if the code and message are identical.
   178  func (e *Error) Is(target error) bool {
   179  	tse, ok := target.(*Error)
   180  	if !ok {
   181  		return false
   182  	}
   183  	return proto.Equal(e.e, tse.e)
   184  }
   185  
   186  // FromError returns a Status representing err if it was produced from this
   187  // package or has a method `GRPCStatus() *Status`. Otherwise, ok is false and a
   188  // Status is returned with codes.Unknown and the original error message.
   189  func FromError(err error) (s *Status, ok bool) {
   190  	if err == nil {
   191  		return nil, true
   192  	}
   193  	var se Iface
   194  	if errors.As(err, &se) {
   195  		return se.GRPCStatus(), true
   196  	}
   197  	return New(codes.Unknown, err.Error()), false
   198  }
   199  
   200  // Convert is a convenience function which removes the need to handle the
   201  // boolean return value from FromError.
   202  func Convert(err error) *Status {
   203  	s, _ := FromError(err)
   204  	return s
   205  }
   206  
   207  // Code returns the Code of the error if it is a Status error, codes.OK if err
   208  // is nil, or codes.Unknown otherwise.
   209  func Code(err error) codes.Code {
   210  	// Don't use FromError to avoid allocation of OK status.
   211  	if err == nil {
   212  		return codes.OK
   213  	}
   214  	var se Iface
   215  	if errors.As(err, &se) {
   216  		return se.GRPCStatus().Code()
   217  	}
   218  	return codes.Unknown
   219  }
   220  
   221  // FromContextError converts a context error into a Status.  It returns a
   222  // Status with codes.OK if err is nil, or a Status with codes.Unknown if err is
   223  // non-nil and not a context error.
   224  func FromContextError(err error) *Status {
   225  	switch err {
   226  	case nil:
   227  		return nil
   228  	case context.DeadlineExceeded:
   229  		return New(codes.DeadlineExceeded, err.Error())
   230  	case context.Canceled:
   231  		return New(codes.Canceled, err.Error())
   232  	default:
   233  		return New(codes.Unknown, err.Error())
   234  	}
   235  }