github.com/graemephi/kahugo@v0.62.3-0.20211121071557-d78c0423784d/resources/post_publish.go (about)

     1  // Copyright 2020 The Hugo Authors. All rights reserved.
     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  // http://www.apache.org/licenses/LICENSE-2.0
     7  //
     8  // Unless required by applicable law or agreed to in writing, software
     9  // distributed under the License is distributed on an "AS IS" BASIS,
    10  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    11  // See the License for the specific language governing permissions and
    12  // limitations under the License.
    13  
    14  package resources
    15  
    16  import (
    17  	"github.com/gohugoio/hugo/resources/postpub"
    18  	"github.com/gohugoio/hugo/resources/resource"
    19  )
    20  
    21  type transformationKeyer interface {
    22  	TransformationKey() string
    23  }
    24  
    25  // PostProcess wraps the given Resource for later processing.
    26  func (spec *Spec) PostProcess(r resource.Resource) (postpub.PostPublishedResource, error) {
    27  	key := r.(transformationKeyer).TransformationKey()
    28  	spec.postProcessMu.RLock()
    29  	result, found := spec.PostProcessResources[key]
    30  	spec.postProcessMu.RUnlock()
    31  	if found {
    32  		return result, nil
    33  	}
    34  
    35  	spec.postProcessMu.Lock()
    36  	defer spec.postProcessMu.Unlock()
    37  
    38  	// Double check
    39  	result, found = spec.PostProcessResources[key]
    40  	if found {
    41  		return result, nil
    42  	}
    43  
    44  	result = postpub.NewPostPublishResource(spec.incr.Incr(), r)
    45  	if result == nil {
    46  		panic("got nil result")
    47  	}
    48  	spec.PostProcessResources[key] = result
    49  
    50  	return result, nil
    51  }