github.com/hasnat/dolt/go@v0.0.0-20210628190320-9eb5d843fbb7/store/blobstore/errors.go (about)

     1  // Copyright 2019 Dolthub, Inc.
     2  //
     3  // Licensed under the Apache License, Version 2.0 (the "License");
     4  // you may not use this file except in compliance with the License.
     5  // You may obtain a copy of the License at
     6  //
     7  //     http://www.apache.org/licenses/LICENSE-2.0
     8  //
     9  // Unless required by applicable law or agreed to in writing, software
    10  // distributed under the License is distributed on an "AS IS" BASIS,
    11  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    12  // See the License for the specific language governing permissions and
    13  // limitations under the License.
    14  
    15  package blobstore
    16  
    17  // NotFound is an error type used only when a key is not found in a Blobstore.
    18  type NotFound struct {
    19  	Key string
    20  }
    21  
    22  // Error returns the key which was not found
    23  func (nf NotFound) Error() string {
    24  	return "Blob not found: " + nf.Key
    25  }
    26  
    27  // IsNotFoundError is a helper method used to determine if returned errors resulted
    28  // because the key didn't exist as opposed to something going wrong.
    29  func IsNotFoundError(err error) bool {
    30  	_, ok := err.(NotFound)
    31  
    32  	return ok
    33  }
    34  
    35  // CheckAndPutError is an error type used when CheckAndPut fails because of a version
    36  // mismatch.
    37  type CheckAndPutError struct {
    38  	Key             string
    39  	ExpectedVersion string
    40  	ActualVersion   string
    41  }
    42  
    43  // Error (Required method of error) returns an error message for debugging
    44  func (err CheckAndPutError) Error() string {
    45  	return "Blob: \"" + err.Key + "\" expected: \"" + err.ExpectedVersion + "\" actual: \"" + err.ActualVersion + "\""
    46  }
    47  
    48  // IsCheckAndPutError is a helper method used to determine if CheckAndPut errors
    49  // resulted because of version mismatches (Which happens when you have multiple)
    50  // writers of a blob with a given key.
    51  func IsCheckAndPutError(err error) bool {
    52  	_, ok := err.(CheckAndPutError)
    53  
    54  	return ok
    55  }