github.com/linchen2chris/hugo@v0.0.0-20230307053224-cec209389705/tpl/internal/resourcehelpers/helpers.go (about)

     1  // Copyright 2020 The Hugo Authors. All rights reserved.
     2  //
     3  // Portions Copyright The Go 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  // http://www.apache.org/licenses/LICENSE-2.0
     9  //
    10  // Unless required by applicable law or agreed to in writing, software
    11  // distributed under the License is distributed on an "AS IS" BASIS,
    12  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    13  // See the License for the specific language governing permissions and
    14  // limitations under the License.
    15  
    16  package resourcehelpers
    17  
    18  import (
    19  	"errors"
    20  	"fmt"
    21  
    22  	"github.com/gohugoio/hugo/common/maps"
    23  	"github.com/gohugoio/hugo/resources"
    24  )
    25  
    26  // We allow string or a map as the first argument in some cases.
    27  func ResolveIfFirstArgIsString(args []any) (resources.ResourceTransformer, string, bool) {
    28  	if len(args) != 2 {
    29  		return nil, "", false
    30  	}
    31  
    32  	v1, ok1 := args[0].(string)
    33  	if !ok1 {
    34  		return nil, "", false
    35  	}
    36  	v2, ok2 := args[1].(resources.ResourceTransformer)
    37  
    38  	return v2, v1, ok2
    39  }
    40  
    41  // This roundabout way of doing it is needed to get both pipeline behaviour and options as arguments.
    42  func ResolveArgs(args []any) (resources.ResourceTransformer, map[string]any, error) {
    43  	if len(args) == 0 {
    44  		return nil, nil, errors.New("no Resource provided in transformation")
    45  	}
    46  
    47  	if len(args) == 1 {
    48  		r, ok := args[0].(resources.ResourceTransformer)
    49  		if !ok {
    50  			return nil, nil, fmt.Errorf("type %T not supported in Resource transformations", args[0])
    51  		}
    52  		return r, nil, nil
    53  	}
    54  
    55  	r, ok := args[1].(resources.ResourceTransformer)
    56  	if !ok {
    57  		if _, ok := args[1].(map[string]any); !ok {
    58  			return nil, nil, fmt.Errorf("no Resource provided in transformation")
    59  		}
    60  		return nil, nil, fmt.Errorf("type %T not supported in Resource transformations", args[0])
    61  	}
    62  
    63  	m, err := maps.ToStringMapE(args[0])
    64  	if err != nil {
    65  		return nil, nil, fmt.Errorf("invalid options type: %w", err)
    66  	}
    67  
    68  	return r, m, nil
    69  }