commit e19a046c4be9b0654884259b9df94f41561e4fc3
parent a1fe552fc9e622a15010a94281f604eb85bebd84
Author: Bjørn Erik Pedersen <bjorn.erik.pedersen@gmail.com>
Date: Thu, 21 Jan 2021 16:52:32 +0100
js: Add Shims option
This commit adds a new `shims` option to `js.Build` that allows swapping out a component with another.
Fixes #8165
Diffstat:
3 files changed, 46 insertions(+), 35 deletions(-)
diff --git a/docs/content/en/hugo-pipes/js.md b/docs/content/en/hugo-pipes/js.md
@@ -43,19 +43,42 @@ minify [bool]
avoidTDZ {{< new-in "0.78.0" >}}
: There is/was a bug in WebKit with severe performance issue with the tracking of TDZ checks in JavaScriptCore. Enabling this flag removes the TDZ and `const` assignment checks and may improve performance of larger JS codebases until the WebKit fix is in widespread use. See https://bugs.webkit.org/show_bug.cgi?id=199866
+shims {{< new-in "0.81.0" >}}
+: This option allows swapping out a component with another. A common use case is to load dependencies like React from a CDN (with _shims_) when in production, but running with the full bundled `node_modules` dependency during development:
+
+```
+{{ $shims := dict "react" "js/shims/react.js" "react-dom" "js/shims/react-dom.js" }}
+{{ $js = $js | js.Build dict "shims" $shims }}
+```
+
+The _shim_ files may look like these:
+
+```js
+// js/shims/react.js
+module.exports = window.React;
+```
+
+```js
+// js/shims/react-dom.js
+module.exports = window.ReactDOM;
+```
+
+
+With the above, these imports should work in both scenarios:
+
+```js
+import * as React from 'react'
+import * as ReactDOM from 'react-dom';
+```
+
target [string]
: The language target.
One of: `es5`, `es2015`, `es2016`, `es2017`, `es2018`, `es2019`, `es2020` or `esnext`.
Default is `esnext`.
externals [slice]
-: External dependencies. If a dependency should not be included in the bundle (Ex. library loaded from a CDN.), it should be listed here.
-
-```go-html-template
-{{ $externals := slice "react" "react-dom" }}
-```
+: External dependencies. Use this to trim dependencies you know will never be executed. See https://esbuild.github.io/api/#external
-> Marking a package as external doesn't imply that the library can be loaded from a CDN. It simply tells Hugo not to expand/include the package in the JS file.
defines [map]
: Allow to define a set of string replacement to be performed when building. Should be a map where each key is to be replaced by its value.
@@ -145,29 +168,4 @@ Or with options:
<script type="text/javascript" src="{{ $built.RelPermalink }}" defer></script>
```
-#### Shimming a JS library
-
-It's a common practice to load external libraries using a content delivery network (CDN) rather than importing all packages in a single JS file. To load scripts from a CDN with Hugo, you'll need to shim the libraries as follows. In this example, `react` and `react-dom` will be shimmed.
-
-First, add React and ReactDOM [CDN script tags](https://reactjs.org/docs/add-react-to-a-website.html#tip-minify-javascript-for-production) in your HTML template files. Then create `assets/js/shims/react.js` and `assets/js/shims/react-dom.js` with the following contents:
-```js
-// In assets/js/shims/react.js
-module.exports = window.React;
-
-// In assets/js/shims/react-dom.js
-module.exports = window.ReactDOM;
-```
-
-Finally, add the following to your project's `package.json`:
-```json
-{
- "browser": {
- "react": "./assets/js/shims/react.js",
- "react-dom": "./assets/js/shims/react-dom.js"
- }
-}
-```
-
-This tells Hugo's `js.Build` command to look for `react` and `react-dom` in the project's `assets/js/shims` folder. Note that the `browser` field in your `package.json` file will cause React and ReactDOM to be excluded from your JavaScript bundle. Therefore, **it is unnecessary to add them to the `js.Build` command's `externals` argument.**
-That's it! You should now have a browser-friendly JS which can use external JS libraries.
diff --git a/hugolib/js_test.go b/hugolib/js_test.go
@@ -187,7 +187,7 @@ path="github.com/gohugoio/hugoTestProjectJSModImports"
go 1.15
-require github.com/gohugoio/hugoTestProjectJSModImports v0.5.0 // indirect
+require github.com/gohugoio/hugoTestProjectJSModImports v0.8.0 // indirect
`)
@@ -215,4 +215,9 @@ Hello3 from mod2. Date from date-fns: ${today}
Hello from lib in the main project
Hello5 from mod2.
var myparam = "Hugo Rocks!";`)
+
+ // React JSX, verify the shimming.
+ b.AssertFileContent("public/js/like.js", `@v0.8.0/assets/js/shims/react.js
+module.exports = window.ReactDOM;
+`)
}
diff --git a/resources/resource_transformers/js/options.go b/resources/resource_transformers/js/options.go
@@ -62,11 +62,14 @@ type Options struct {
Format string
// External dependencies, e.g. "react".
- Externals []string `hash:"set"`
+ Externals []string
// User defined symbols.
Defines map[string]interface{}
+ // Maps a component import to another.
+ Shims map[string]string
+
// User defined params. Will be marshaled to JSON and available as "@params", e.g.
// import * as params from '@params';
Params interface{}
@@ -138,6 +141,13 @@ func createBuildPlugins(c *Client, opts Options) ([]api.Plugin, error) {
fs := c.rs.Assets
resolveImport := func(args api.OnResolveArgs) (api.OnResolveResult, error) {
+ impPath := args.Path
+ if opts.Shims != nil {
+ override, found := opts.Shims[impPath]
+ if found {
+ impPath = override
+ }
+ }
isStdin := args.Importer == stdinImporter
var relDir string
if !isStdin {
@@ -153,8 +163,6 @@ func createBuildPlugins(c *Client, opts Options) ([]api.Plugin, error) {
relDir = filepath.Dir(opts.sourcefile)
}
- impPath := args.Path
-
// Imports not starting with a "." is assumed to live relative to /assets.
// Hugo makes no assumptions about the directory structure below /assets.
if relDir != "" && strings.HasPrefix(impPath, ".") {