Reader: Add post in API response to feed

[artemiomorales]

Related to https://github.com/Automattic/loop/issues/519

Proposed Changes

• Adds a reader/quick-post-v2 config flag
• Adds posts newly created via Quick Edit immediately to the stream store when behind the config flag
• Adds an isSynthetic property to the post so we can determine whether to render it in the steam component

reader-quick-post.mp4

Why are these changes being made?

• Ongoing work as part of the Quick Edit functionality.

Testing Instructions

• Visit /reader?flags=reader/quick-post,reader/quick-post-v2
• Add a new post using the quick editor
• Verify that the post appears in the feed

Pre-merge Checklist

• Has the general commit checklist been followed? (PCYsg-hS-p2)
• Have you written new tests for your changes?
• Have you tested the feature in Simple (P9HQHe-k8-p2), Atomic (P9HQHe-jW-p2), and self-hosted Jetpack sites (PCYsg-g6b-p2)?
• Have you checked for TypeScript, React or other console errors?
• Have you used memoizing on expensive computations? More info in Memoizing with create-selector and Using memoizing selectors and Our Approach to Data
• Have we added the "[Status] String Freeze" label as soon as any new strings were ready for translation (p4TIVU-5Jq-p2)?
  • For UI changes, have we tested the change in various languages (for example, ES, PT, FR, or DE)? The length of text and words vary significantly between languages.
• For changes affecting Jetpack: Have we added the "[Status] Needs Privacy Updates" label if this pull request changes what data or activity we track or use (p4TIVU-aUh-p2)?

[matticbot]

Calypso Live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-134813

Jetpack Cloud live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-134813&env=jetpack

Automattic for Agencies live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-134813&env=a8c-for-agencies

[matticbot]

This PR modifies the release build for the following Calypso Apps:

For info about this notification, see here: PCYsg-OT6-p2

• notifications
• wpcom-block-editor

To test WordPress.com changes, run install-plugin.sh $pluginSlug try/reader-quick-post-refresh on your sandbox.

[matticbot]

Here is how your PR affects size of JS and CSS bundles shipped to the user's browser:

Sections (~220 bytes added 📈 [gzipped])

name                             parsed_size           gzip_size
reader                                +534 B  (+0.0%)     +209 B  (+0.0%)
plugins                               +307 B  (+0.0%)      +89 B  (+0.0%)
jetpack-cloud-plugin-management       +307 B  (+0.0%)      +89 B  (+0.0%)
home                                  +307 B  (+0.0%)      +89 B  (+0.0%)
a8c-for-agencies-plugins              +307 B  (+0.0%)      +89 B  (+0.0%)
write-flow                            +118 B  (+0.0%)      +36 B  (+0.0%)
site-blocks                           +118 B  (+0.0%)      +36 B  (+0.0%)
build-flow                            +118 B  (+0.0%)      +36 B  (+0.0%)
comments                               +47 B  (+0.0%)      +11 B  (+0.0%)

Sections contain code specific for a given set of routes. Is downloaded and parsed only when a particular route is navigated to.

Async-loaded Components (~36 bytes added 📈 [gzipped])

name                                                     parsed_size           gzip_size
async-load-design-blocks                                      +118 B  (+0.0%)      +36 B  (+0.0%)
async-load-calypso-components-web-preview-component           +118 B  (+0.0%)      +36 B  (+0.0%)
async-load-calypso-blocks-support-article-dialog-dialog       +118 B  (+0.1%)      +36 B  (+0.1%)

React components that are loaded lazily, when a certain part of UI is displayed for the first time.

Legend

What is parsed and gzip size?

Parsed Size: Uncompressed size of the JS and CSS files. This much code needs to be parsed and stored in memory.
Gzip Size: Compressed size of the JS and CSS files. This much data needs to be downloaded over network.

Generated by performance advisor bot at iscalypsofastyet.com.

[artemiomorales]

Rather than use this isSynthetic flag, what I want to do is introduce a new object called temporaryItems or similar in the posts store, which we would populate with the API response, and use that in conjunction with the regular items property from the posts store when rendering the Stream component.

[DustyReagan]

Makes sense.