React-rails: Is it possible to use association in component -- a Rails app

[wenwei63029869]

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(Describe your issue here)
I am trying to an array of posts which have several comments belongs each posts to a component. I already tested that I can't use post.comments within the component. One solution I can think of is to create a hash with post.id as key and an array of comment instances as value. Then I will be able to get to right comment array as long as I know the post_id. I wonder if there is a better to do it.

[rmosolgo]

Usually, I handle this by including the children (comments) with the parent (post). For example:

<!-- include the comments in each post's JSON: --> 
<% posts_json = @posts.include(:comments).map { |post| post.as_json.merge({comments: post.comments.as_json}) } %>
<!-- then pass the JSON to React: -->
<%= react_component("PostsList", {posts: posts_json}) %>

That way, you _can_ use post.comments in the component.

Would that work in your case?

[wenwei63029869]

It is almost correct. Just a few changes to make it works:

<% posts_json = Post.includes(:comments).map { |post| post.as_json.merge({comments: post.comments.as_json}) } %>

Thank you so much, @rmosolgo

[rmosolgo]

Glad it worked!