Joaquim Domingos António

If you wish to ‘Create comments’ using REST API, without exposing Administrator credentials to the Front-End application, you are at the right place. Since WordPress 4.7, REST API was natively included in WordPress.
In order to ‘Create a comment’ , the authentication for a user with ‘Administrator’ role is required. While this is a deliberately done for security reasons, such implementation makes it very hard for Front-End applications to implement a simple ‘Post Comment’ or ‘Reply Comment’ function.
This plugin fulfils such requirement by extending the existing WordPress REST API endpoints.
Requirements:
Minimum PHP version: 7.0 
Minimum WordPress version: 5.5
Installation:
Download the plugin form wordpress marketplace install it like any other WordPress plugin. 
After the installation activate the plugin through the ‘Plugins’ menu in WordPress
Endpoint:
When this plugin is installed one new endpoint is added to the wp/v2 namespace.
 Endpoint 
 HTTP Verb 
 Permalinks
 */wp-json/wp/v2/comments/create 
 POST 
 enabled
 */?rest_route=/wp/v2/comments/create 
 POST 
 disabled
Usage:
<ol>
<li>Create a Comment</li>
</ol>
To create a comment using REST API, send a <code>POST</code> request to:
<blockquote>
<code>/wp-json/wp/v2/comments/create</code> – if permalinks is enabled on your wordpress website.
</blockquote>
Or
<blockquote>
<code>/?rest_route=/wp/v2/comments/create</code> if permalinks is not enabled on your wordpress website.
</blockquote>
With a JSON body, as shown bellow:
<pre><code>`Json
</code></pre>
{ 
 “post”: “Post ID”, 
 “author_name”: “Comment Author’s name”, 
 “author_email”: “Comment Author’s email”, 
 “content”: “Comment content” 
} 
 `
The content may also be send as an object:
<pre><code>`Json
</code></pre>
{ 
 “post”: “Post ID”, 
 “author_name”: “Comment Author’s name”, 
 “author_email”: “Comment Author’s email”, 
 “content”: { 
 “raw”:”Comment content” 
 } 
} 
 `
Set header to:
<pre><code>`
</code></pre>
content-type: application/json 
 ` 
If successful, you should receive a response with the data of the created comment:
<pre><code>`Json
</code></pre>
{ 
 “id”: “[comment id]”, 
 “status”: “[comment status]”, 
 “message”:”[server response message]” 
} 
 `
In response header the status code should be:
<pre><code>`Http
</code></pre>
HTTP 201 Created 
 `
<ol>
<li>Reply a comment</li>
</ol>
To reply a comment you just need to add the field parent for the parent comment to the JSON body
<pre><code>`Json
</code></pre>
{ 
 “post”: “Post ID”, 
 “author_name”: “Comment Author’s name”, 
 “author_email”: “Comment Author’s email”, 
 “content”: “Comment content”, 
 “parent”:”Comment parent ID” 
} 
 `
<blockquote>
Note: Ensure the parent is a comment id that belongs to the post informed in the field post. The comment parent post id must match the post id otherwise the following error will be shown:
</blockquote>
<pre><code>`Json
</code></pre>
{ 
 “code”: “rest_post_mismatch_parent_post_id”, 
 “message”: “Post ID and Parent post ID does not match”, 
 “data”: { 
 “status”: 400 
 } 
} 
 `
<h3>Contact</h3>
If there is any thing to say about the plugin fill free to <a href="mailto:sopport@appsdabanda.com" rel="nofollow ugc">contact us</a>.

REST API Comment

REST API Comment adds in the 'Comment creation' function to the Wordpress REST API.

Acato

Richard Korthuis

This plugin is no longer updated, but is open for adoption 
As of Yoast SEO version 16.7 the functionality provided by this plugin is now <a href="https://developer.yoast.com/customization/apis/rest-api/" rel="nofollow ugc">part of the Yoast SEO plugin</a> itself. This plugin will no longer be updated, but is open for adoption. If you are interested in adopting this plugin, please contact the authors.
Are you using WordPress for a headless set-up, using the WP REST API? And would you like to use the Yoast SEO plugin just like you would for any other project? This plugin adds the meta tags generated by the Yoast SEO plugin to the WP REST API output, allowing your headless set-up to implement them. Also when you are using Yoast SEO Premium you have the option to retrieve redirects throught the API: this plugin adds a custom endpoint (<code>/wp-rest-yoast-meta/v1/redirects</code>) to provide those redirects in a JSON format. Since Yoast 11.0 JSON LD Schema.org data is also supported and is now also available through the WP REST API when using this plugin.
<h3>Installation from within WordPress</h3>
<ol>
<li>Visit ‘Plugins > Add New’ (or ‘My Sites > Network Admin > Plugins > Add New’ if you are on a multisite installation).</li>
<li>Search for ‘WP REST Yoast Meta’.</li>
<li>Activate the WP REST Yoast Meta plugin through the ‘Plugins’ menu in WordPress.</li>
</ol>
<h3>Installation manually</h3>
<ol>
<li>Upload the <code>wp-rest-yoast-meta</code> folder to the <code>/wp-content/plugins/</code> directory.</li>
<li>Activate the WP REST Yoast Meta plugin through the ‘Plugins’ menu in WordPress.</li>
</ol>

WP REST Yoast Meta

Adds meta tags as generated by Yoast SEO to the WP REST API. And adds a custom endpoint to retrieve all redirects as they are set in Yoast SEO Premium …

REST API Comment vs WP REST Yoast Meta