spfx-fast-serve

SPFx Fast Serve Tool

A command line utility, which modifies your SharePoint Framework solution, so that it runs continuous serve command as fast as possible.

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Compare "refresh" time (the time needed to compile your project when you change a file and start refreshing a page in a browser):

NOTE: The actual time depends on the environment, hardware, but at least you can see the difference

	gulp serve	spfx-fast-serve
Default "Hello World" React web part	3-5 sec	0.3-0.5 sec
PnP Modern Search solution	28-34 sec	2-4 sec
SP Starter Kit solution (v1)	40-50 sec	2-3 sec

Read more info in my blog post here.

How to use

1. npm install spfx-fast-serve -g
2. Open a command line in a folder with your SharePoint Framework solution you want to speed up.
3. Run spfx-fast-serve and follow instructions. In most cases you shouldn't do anything specific and the cli "just works".
4. Run npm install
5. Run npm run serve and enjoy the incredible speed of serve command!

Which SharePoint Framework versions are supported

If you develop for SharePoint Online, simply use the latests version of the tool.
If you target is SharePoint 2019 (which uses SharePoint Framework 1.4.1), then run specific spfx-fast-serve version with SP 2019 support:

npx spfx-fast-serve@1.4.x

SharePoint 2016 is NOT supported.

How it works

The tool adds necessary files to run your own webpack based build with webpack dev server. Technically it's a custom webpack build, which produces the same output files as SharePoint Framework build pipeline, but does it a lot faster, because of a number of improvements:

• all compilation are done in a memory with webpack, no additional "copy", "prepare", "typescript", "whatever" tasks.
• incremental TypeScript compilation when a file is being changed. It means only necessary files are compiled, not everything.
• asynchronous type checking and linting.

Also

• supports local and hosted workbench
• live reloading (for hosted workbench as well)
• debugging from VSCode with Chrome Debugger extension
• doesn't mess up your default SPFx build. If you have troubles, simply switch back to regular gulp serve

With spfx-fast-serve you will be able to significantly reduce the time from code change to a page refresh in a browser (a few times faster than the default gulp serve command).

FAQs / known issues

1. When I run npm run serve I see

ERROR in <Component>.tsx Cannot find module './<Component>.module.scss':

a. Try to explicitly change and then save any of .tsx files in the solution in order to trigger the build. Maybe the error will disappear automatically. If not, go to #b

b. Check that you use styles variable in .tsx file. For example, if you have import styles from './<Component>.module.scss'; and you don't have usages of styles in your <Component>.tsx, you will see the error. Simply delete unused import. If it's not the case, goto #c.

c. Maybe you don't have <Component>.module.scss.d.ts which is generated automatically. Request generation by going to <Component>.module.scss and explicitly saving the file using Ctrl+S combination or just by changing something and saving. This should generate <Component>.module.scss.d.ts and fix the issue. If not, please raise an issue.

2. After I applied sfpx-fast-serve tool I have formatting broken in package.json and gulpfile.js

• sfpx-fast-serve patches those files and doesn't respect original file formatting (tabs vs whitespace, size, etc.). You have to fix it afterwards, if needed.

3. I added a new dependency in my solution (or started using new import from "@microsoft/*" modules) and now I see some strange errors

• every time you introduce a new dependency for your solution, you should re-run npm run serve command, so that it picks up all new dependencies correctly.

4. When I modify localization files, live reload doesn't work

• this scenario isn't supported, thus in that case you have to reload page manually

5. I use custom loaders and / or webpack modifications in my gulpfile.js

• if you use custom webpack loaders or other webpack modifications via build.configureWebpack.mergeConfig feature, you should manually apply them to webpack.js file created by the cli to make everything work

6. Does it support React Hot Module Replacement (aka HMR)?

• HMR is not supported. I tried different things, but was not able to make it work. If you have ideas, please welcome to issues or PRs :)

Manual merge warning

As part of the steps, spfx-fast-serve modifies your gulpfile.js. In most cases it smoothly merges all required stuff. However, in case if you use build.configureWebpack.mergeConfig in your code, the tool is unable to perform merge correctly. In that case you should do manual merge.

Simply locate you code with build.configureWebpack.mergeConfig and insert the line

fs.writeFileSync("./temp/_webpack_config.json", JSON.stringify(generatedConfiguration, null, 2));

at the beginning of your additionalConfiguration callback method.
For example:

  build.configureWebpack.mergeConfig({
    additionalConfiguration: (generatedConfiguration) => {

      fs.writeFileSync("./temp/_webpack_config.json", JSON.stringify(generatedConfiguration, null, 2)); // <-- the needed line

      // your stuff goes here

      return generatedConfiguration;
    }
  });

Additionally at the top of your gulpfile.js add fs tool import: const fs = require("fs");.

That's it!

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Please use issues for questions, suggestions and, of course, issues.