fix: copy static image as it is if image compression fail

[endiliey]

Motivation

Fix #701

There is no error handling on https://github.com/facebook/Docusaurus/blob/ef80581e8ef950a0865fc7851407c672c4bbd510/lib/server/generate.js#L255-L264

If the image compression fails, it will cause the image to be missing.

Example:
https://circleci.com/gh/facebook/Docusaurus/2846

The build succeed but along the line there is an unhandled promise. Causing christopher-chedeau.jpg and ricky-vetter.jpg to be missing.

This PR add a fallback functionality to copy the image as it is if the image compression fail

Have you read the Contributing Guidelines on pull requests?

Yes

Test Plan

https://deploy-preview-887--docusaurus-preview.netlify.com/

Related PRs

#654

[docusaurus-bot]

Deploy preview for docusaurus-preview ready!

Built with commit dfc0619

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[JoelMarcey]

👍

It would be interesting to see what errors are being thrown at random times to cause images not to compress correctly.

On that note, do you think having the image compression functionality is still useful for us? Or is it causing more problems than it helps?

[JoelMarcey]

Was this always wrong? I see you removed this from your update.

[endiliey]

It's not really wrong but this is not declarative enough. I think using function from nodejs path clearly shows the intent.

const targetDirectory = path.dirname(targetFile);

The previous code in the below section

mkdirp.sync(path.dirname(targetDirectory));

is wrong though. It should be

mkdirp.sync(targetDirectory);

[endiliey]

@JoelMarcey i think it definitely help in the sense that it reduces the website loading page since image size is reduced. It's causing problem because we completely skip that image if compression is failing. Ex: #701

[endiliey]

It still fails but at least the image is now intact and image is copied to build.

Here is the error printed:

{ Error: Error in file: /home/circleci/docusaurus/website/static/img/christopher-chedeau.jpg

spawn /home/circleci/docusaurus/node_modules/jpegtran-bin/vendor/jpegtran ENOENT
    at _errnoException (util.js:992:11)
    at Process.ChildProcess._handle.onexit (internal/child_process.js:190:19)
    at onErrorNT (internal/child_process.js:372:16)
    at _combinedTickCallback (internal/process/next_tick.js:138:11)
    at process._tickCallback (internal/process/next_tick.js:180:9)
  code: 'ENOENT',
  errno: 'ENOENT',
  syscall: 'spawn /home/circleci/docusaurus/node_modules/jpegtran-bin/vendor/jpegtran',
  path: '/home/circleci/docusaurus/node_modules/jpegtran-bin/vendor/jpegtran',
  spawnargs: 
   [ '-copy',
     'none',
     '-optimize',
     '-outfile',
     '/tmp/c0b1b392-9983-40e2-bc2f-dca2418d460c',
     '/tmp/aa77e0b6-cbfa-4f21-b08f-02ed65dff725' ],
  killed: false,
  stdout: '',
  stderr: '',
  failed: true,
  signal: null,
  cmd: '/home/circleci/docusaurus/node_modules/jpegtran-bin/vendor/jpegtran -copy none -optimize -outfile /tmp/c0b1b392-9983-40e2-bc2f-dca2418d460c /tmp/aa77e0b6-cbfa-4f21-b08f-02ed65dff725',
  timedOut: false }
{ Error: Error in file: /home/circleci/docusaurus/website/static/img/ricky-vetter.jpg

[JoelMarcey]

Bad image? Or buggy compressor?

_{Sent with GitHawk}

[ahmadalfy]

@JoelMarcey I think it should copy in either cases ... I didn't notice that case would happen to be honest