Naveen Sampath | 04696f7 | 2022-06-13 15:19:14 +0530 | [diff] [blame^] | 1 | /* |
| 2 | * Licensed to the Apache Software Foundation (ASF) under one |
| 3 | * or more contributor license agreements. See the NOTICE file |
| 4 | * distributed with this work for additional information |
| 5 | * regarding copyright ownership. The ASF licenses this file |
| 6 | * to you under the Apache License, Version 2.0 (the |
| 7 | * "License"); you may not use this file except in compliance |
| 8 | * with the License. You may obtain a copy of the License at |
| 9 | * |
| 10 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 11 | * |
| 12 | * Unless required by applicable law or agreed to in writing, |
| 13 | * software distributed under the License is distributed on an |
| 14 | * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| 15 | * KIND, either express or implied. See the License for the |
| 16 | * specific language governing permissions and limitations |
| 17 | * under the License. |
| 18 | */ |
| 19 | |
| 20 | package thrift |
| 21 | |
| 22 | import ( |
| 23 | "errors" |
| 24 | ) |
| 25 | |
| 26 | // Generic Thrift exception |
| 27 | type TException interface { |
| 28 | error |
| 29 | |
| 30 | TExceptionType() TExceptionType |
| 31 | } |
| 32 | |
| 33 | // Prepends additional information to an error without losing the Thrift exception interface |
| 34 | func PrependError(prepend string, err error) error { |
| 35 | msg := prepend + err.Error() |
| 36 | |
| 37 | var te TException |
| 38 | if errors.As(err, &te) { |
| 39 | switch te.TExceptionType() { |
| 40 | case TExceptionTypeTransport: |
| 41 | if t, ok := err.(TTransportException); ok { |
| 42 | return prependTTransportException(prepend, t) |
| 43 | } |
| 44 | case TExceptionTypeProtocol: |
| 45 | if t, ok := err.(TProtocolException); ok { |
| 46 | return prependTProtocolException(prepend, t) |
| 47 | } |
| 48 | case TExceptionTypeApplication: |
| 49 | var t TApplicationException |
| 50 | if errors.As(err, &t) { |
| 51 | return NewTApplicationException(t.TypeId(), msg) |
| 52 | } |
| 53 | } |
| 54 | |
| 55 | return wrappedTException{ |
| 56 | err: err, |
| 57 | msg: msg, |
| 58 | tExceptionType: te.TExceptionType(), |
| 59 | } |
| 60 | } |
| 61 | |
| 62 | return errors.New(msg) |
| 63 | } |
| 64 | |
| 65 | // TExceptionType is an enum type to categorize different "subclasses" of TExceptions. |
| 66 | type TExceptionType byte |
| 67 | |
| 68 | // TExceptionType values |
| 69 | const ( |
| 70 | TExceptionTypeUnknown TExceptionType = iota |
| 71 | TExceptionTypeCompiled // TExceptions defined in thrift files and generated by thrift compiler |
| 72 | TExceptionTypeApplication // TApplicationExceptions |
| 73 | TExceptionTypeProtocol // TProtocolExceptions |
| 74 | TExceptionTypeTransport // TTransportExceptions |
| 75 | ) |
| 76 | |
| 77 | // WrapTException wraps an error into TException. |
| 78 | // |
| 79 | // If err is nil or already TException, it's returned as-is. |
| 80 | // Otherwise it will be wraped into TException with TExceptionType() returning |
| 81 | // TExceptionTypeUnknown, and Unwrap() returning the original error. |
| 82 | func WrapTException(err error) TException { |
| 83 | if err == nil { |
| 84 | return nil |
| 85 | } |
| 86 | |
| 87 | if te, ok := err.(TException); ok { |
| 88 | return te |
| 89 | } |
| 90 | |
| 91 | return wrappedTException{ |
| 92 | err: err, |
| 93 | msg: err.Error(), |
| 94 | tExceptionType: TExceptionTypeUnknown, |
| 95 | } |
| 96 | } |
| 97 | |
| 98 | type wrappedTException struct { |
| 99 | err error |
| 100 | msg string |
| 101 | tExceptionType TExceptionType |
| 102 | } |
| 103 | |
| 104 | func (w wrappedTException) Error() string { |
| 105 | return w.msg |
| 106 | } |
| 107 | |
| 108 | func (w wrappedTException) TExceptionType() TExceptionType { |
| 109 | return w.tExceptionType |
| 110 | } |
| 111 | |
| 112 | func (w wrappedTException) Unwrap() error { |
| 113 | return w.err |
| 114 | } |
| 115 | |
| 116 | var _ TException = wrappedTException{} |