ref: 30159b58e9de7fc9026996503d86c4646d2d93ff
dir: /resources/resource_transformers/js/build.go/
// Copyright 2020 The Hugo Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package js
import (
"fmt"
"io/ioutil"
"path"
"strings"
"github.com/spf13/cast"
"github.com/gohugoio/hugo/helpers"
"github.com/gohugoio/hugo/hugolib/filesystems"
"github.com/gohugoio/hugo/media"
"github.com/gohugoio/hugo/resources/internal"
"github.com/mitchellh/mapstructure"
"github.com/evanw/esbuild/pkg/api"
"github.com/gohugoio/hugo/resources"
"github.com/gohugoio/hugo/resources/resource"
)
type Options struct {
// If not set, the source path will be used as the base target path.
// Note that the target path's extension may change if the target MIME type
// is different, e.g. when the source is TypeScript.
TargetPath string
// Whether to minify to output.
Minify bool
// Whether to write mapfiles (currently inline only)
SourceMap string
// The language target.
// One of: es2015, es2016, es2017, es2018, es2019, es2020 or esnext.
// Default is esnext.
Target string
// The output format.
// One of: iife, cjs, esm
// Default is to esm.
Format string
// External dependencies, e.g. "react".
Externals []string `hash:"set"`
// User defined symbols.
Defines map[string]interface{}
// What to use instead of React.createElement.
JSXFactory string
// What to use instead of React.Fragment.
JSXFragment string
mediaType media.Type
outDir string
contents string
sourcefile string
resolveDir string
}
func decodeOptions(m map[string]interface{}) (Options, error) {
var opts Options
if err := mapstructure.WeakDecode(m, &opts); err != nil {
return opts, err
}
if opts.TargetPath != "" {
opts.TargetPath = helpers.ToSlashTrimLeading(opts.TargetPath)
}
opts.Target = strings.ToLower(opts.Target)
opts.Format = strings.ToLower(opts.Format)
return opts, nil
}
type Client struct {
rs *resources.Spec
sfs *filesystems.SourceFilesystem
}
func New(fs *filesystems.SourceFilesystem, rs *resources.Spec) *Client {
return &Client{rs: rs, sfs: fs}
}
type buildTransformation struct {
optsm map[string]interface{}
rs *resources.Spec
sfs *filesystems.SourceFilesystem
}
func (t *buildTransformation) Key() internal.ResourceTransformationKey {
return internal.NewResourceTransformationKey("jsbuild", t.optsm)
}
func (t *buildTransformation) Transform(ctx *resources.ResourceTransformationCtx) error {
ctx.OutMediaType = media.JavascriptType
opts, err := decodeOptions(t.optsm)
if err != nil {
return err
}
if opts.TargetPath != "" {
ctx.OutPath = opts.TargetPath
} else {
ctx.ReplaceOutPathExtension(".js")
}
src, err := ioutil.ReadAll(ctx.From)
if err != nil {
return err
}
sdir, sfile := path.Split(ctx.SourcePath)
opts.sourcefile = sfile
opts.resolveDir = t.sfs.RealFilename(sdir)
opts.contents = string(src)
opts.mediaType = ctx.InMediaType
buildOptions, err := toBuildOptions(opts)
if err != nil {
return err
}
result := api.Build(buildOptions)
if len(result.Errors) > 0 {
return fmt.Errorf("%s", result.Errors[0].Text)
}
ctx.To.Write(result.OutputFiles[0].Contents)
return nil
}
func (c *Client) Process(res resources.ResourceTransformer, opts map[string]interface{}) (resource.Resource, error) {
return res.Transform(
&buildTransformation{rs: c.rs, sfs: c.sfs, optsm: opts},
)
}
func toBuildOptions(opts Options) (buildOptions api.BuildOptions, err error) {
var target api.Target
switch opts.Target {
case "", "esnext":
target = api.ESNext
case "es5":
target = api.ES5
case "es6", "es2015":
target = api.ES2015
case "es2016":
target = api.ES2016
case "es2017":
target = api.ES2017
case "es2018":
target = api.ES2018
case "es2019":
target = api.ES2019
case "es2020":
target = api.ES2020
default:
err = fmt.Errorf("invalid target: %q", opts.Target)
return
}
mediaType := opts.mediaType
if mediaType.IsZero() {
mediaType = media.JavascriptType
}
var loader api.Loader
switch mediaType.SubType {
// TODO(bep) ESBuild support a set of other loaders, but I currently fail
// to see the relevance. That may change as we start using this.
case media.JavascriptType.SubType:
loader = api.LoaderJS
case media.TypeScriptType.SubType:
loader = api.LoaderTS
case media.TSXType.SubType:
loader = api.LoaderTSX
case media.JSXType.SubType:
loader = api.LoaderJSX
default:
err = fmt.Errorf("unsupported Media Type: %q", opts.mediaType)
return
}
var format api.Format
// One of: iife, cjs, esm
switch opts.Format {
case "", "iife":
format = api.FormatIIFE
case "esm":
format = api.FormatESModule
case "cjs":
format = api.FormatCommonJS
default:
err = fmt.Errorf("unsupported script output format: %q", opts.Format)
return
}
var defines map[string]string
if opts.Defines != nil {
defines = cast.ToStringMapString(opts.Defines)
}
var sourceMap api.SourceMap
switch opts.SourceMap {
case "inline":
sourceMap = api.SourceMapInline
case "":
sourceMap = api.SourceMapNone
default:
err = fmt.Errorf("unsupported sourcemap type: %q", opts.SourceMap)
return
}
buildOptions = api.BuildOptions{
Outfile: "",
Bundle: true,
Target: target,
Format: format,
Sourcemap: sourceMap,
MinifyWhitespace: opts.Minify,
MinifyIdentifiers: opts.Minify,
MinifySyntax: opts.Minify,
Outdir: opts.outDir,
Defines: defines,
Externals: opts.Externals,
JSXFactory: opts.JSXFactory,
JSXFragment: opts.JSXFragment,
//Tsconfig: opts.TSConfig,
Stdin: &api.StdinOptions{
Contents: opts.contents,
Sourcefile: opts.sourcefile,
ResolveDir: opts.resolveDir,
Loader: loader,
},
}
return
}