chore(examples): zero-downtime pm2 typescript example

[dschewchenko]

Types of changes

• Bug fix (a non-breaking change which fixes an issue)
• New feature (a non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

New example

Description

Add process.send('ready') when nuxt server is listening
Resolves #3078
I added simple example with pm2 configuration and use listen hook in nuxt.config for sending ready event to pm2

Checklist:

• My change requires a change to the documentation.
• I have updated the documentation accordingly. (PR: #)
• I have added tests to cover my changes (if not applicable, please state why)
• All new and existing tests are passing.

[codecov-io]

Codecov Report

Merging #4907 into dev will decrease coverage by 0.04%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##              dev    #4907      +/-   ##
==========================================
- Coverage   91.79%   91.74%   -0.05%     
==========================================
  Files          73       73              
  Lines        2412     2412              
  Branches      593      593              
==========================================
- Hits         2214     2213       -1     
- Misses        180      181       +1     
  Partials       18       18

Impacted Files	Coverage Δ
packages/vue-renderer/src/renderer.js	94.56% <0%> (-0.55%)	⬇️

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[kevinmarrec]

Thank you for the PR !

I suggested some changes 🙂

Can't wait to be able to have a true zero-downtime PM2 setup 😃

[pimlie]

Would it be possible to extend the example to include documentation and/or a command to have zero-downtime while also having to (re)build Nuxt? It seems to me that currently this example is only about zero-downtime while restarting nuxt server but (again it seems, maybe nuxt-ts works differently on start) to skip the build phase?

[dschewchenko]

Would it be possible to extend the example to include documentation and/or a command to have zero-downtime while also having to (re)build Nuxt? It seems to me that currently this example is only about zero-downtime while restarting nuxt server but (again it seems, maybe nuxt-ts works differently on start) to skip the build phase?

All depends on your need.
Of course, before starting server, you need to build app. It's described in documentation.
Before restarting service you may to deploy all files to temp dir, build there, then move files to your project root, then restart pm2 startOrReload ecosystem.config.js. All described in docs. It's simple.
Recommended steps I will describe in example Readme

[kevinmarrec]

@dschewchenko I changed the title as it's not changing anymore Nuxt core but using the listen hook directly in the example. So it's not a "feature" but a helpful example which we'll be able to link in a proper "PM2 deployment" section or FAQ in documentation.

Thanks for your time ! And thank you @pimlie for the hook tip !

Will test it on my server later this day and approve the PR.

FYI there is a pending PR regarding big perf enhancement using nuxt-ts start on a production server :
#4906