github.com/google/yamlfmt@v0.12.2-0.20240514121411-7f77800e2681/feature.go (about) 1 // Copyright 2022 Google LLC 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 yamlfmt 16 17 import "fmt" 18 19 type FeatureFunc func([]byte) ([]byte, error) 20 21 type Feature struct { 22 Name string 23 BeforeAction FeatureFunc 24 AfterAction FeatureFunc 25 } 26 27 type FeatureList []Feature 28 29 type FeatureApplyMode string 30 31 var ( 32 FeatureApplyBefore FeatureApplyMode = "Before" 33 FeatureApplyAfter FeatureApplyMode = "After" 34 ) 35 36 type FeatureApplyError struct { 37 err error 38 featureName string 39 mode FeatureApplyMode 40 } 41 42 func (e *FeatureApplyError) Error() string { 43 return fmt.Sprintf("Feature %s %sAction failed with error: %v", e.featureName, e.mode, e.err) 44 } 45 46 func (e *FeatureApplyError) Unwrap() error { 47 return e.err 48 } 49 50 func (fl FeatureList) ApplyFeatures(input []byte, mode FeatureApplyMode) ([]byte, error) { 51 // Declare err here so the result variable doesn't get shadowed in the loop 52 var err error 53 result := make([]byte, len(input)) 54 copy(result, input) 55 for _, feature := range fl { 56 if mode == FeatureApplyBefore { 57 if feature.BeforeAction != nil { 58 result, err = feature.BeforeAction(result) 59 } 60 } else { 61 if feature.AfterAction != nil { 62 result, err = feature.AfterAction(result) 63 } 64 } 65 66 if err != nil { 67 return nil, &FeatureApplyError{ 68 err: err, 69 featureName: feature.Name, 70 mode: mode, 71 } 72 } 73 } 74 return result, nil 75 }