Serverless templates not rendering correct data and associated build issues

[dwkns]

I'm trying to create a live preview system for a CMS

Consider this data:

[
  {
    "name": "post1",
    "content": "Content for Post 1"
  },
  {
    "name": "post2",
    "content": "Content for Post 2"
  },
  {
    "name": "post3",
    "content": "Content for Post 3"
  }
]

And this template:

---
layout: _page-skeleton.njk
pagination:
  data: posts
  alias: post
  size: 1
  # serverless: eleventy.serverless.path.id
  # addAllPagesToCollections: true
permalink:
  build: "/posts/{{ post.name | slug }}/"
  preview: "/preview/posts/:id"
---
<h1>Hello from: {{post.name}}</h1>
<p>{{post.content}}</p>

It builds /posts/post1/, /posts/post2/, /posts/post3/ as expected.

The serverless routes on /preview/posts/post1/, /preview/posts/post2/, /preview/posts/post3/ all work, however they all show the data from post1. I think this is expected?

As I understand it from the documentation I should uncomment serverless: eleventy.serverless.path.id which should match id to the slug and therefore render the correct content.

However when I do that, two things happen:

1. Only post1 gets built post2 and post3 do not, no error is given, which was unexpected.
   Make sure you do rm -rf _site netlify netlify.toml .netlify && netlify dev otherwise you can get caught out testing this.
2. None of the serverless /preview/posts/ routes render. I get an "error": "json.filter is not a function" error in the browser and Could not find pagination data, went looking for: post2 (via Error) type errors in the console when I try to visit those pages.

If I add in addAllPagesToCollections: true (thanks to @chriskirknielsen in Discord) it solves the first issue. But I can't get the /preview/posts/... routes to render with the correct data.

It happens in 1.0.2 & 2.0.0-canary.15

Is this a bug, a couple of bugs? Or am I doing something wrong?

Environment:

• OS and Version: Mac (12.5)
• Eleventy Version: 1.0.2 & 2.0.0-canary.15

Additional context
Repo to reproduce

I looked at the this code (from the 11ty website) the only differences I can see are :

• The 11ty websites Authors are rendered with on demand builders rather standard serverless.
• It is not simultaneously building and doing serverless routes in the same template.

I don't know if either of these are relevant.

[treb0r]

I am seeing the same issue with Eleventy serverless. The data from the first item in the pagination array is returned regardless of the route. Using 2.0.0-canary.15.

[dwkns]

Same issue exists on 2.0.0-canaray.16

[dwkns]

OK finally worked it out. Your data has to be an Object not an Array.

If you use this as your data pagination data structure it will work as expected.

{
  "post1": {
    "name": "post1",
    "content": "Content for Post 1"
  },
  "post2": {
    "name": "post2",
    "content": "Content for Post 2"
  },
  "post3": {
    "name": "post3",
    "content": "Content for Post 3"
  }
}

[dwkns]

Closing this as it's a documentation issue, not a Eleventy one.
If anyone else comes across it, there is a working prototype here:
https://github.com/dwkns/eleventy-serverless-issue