Unable to extract multi file attachments fields from BudibaseDB for n8n automation

[iambricegg]

Checklist

• I have searched budibase discussions and github issues to check if my issue already exists

Hosting

• Self
  • Method: docker compose
  • Budibase Version: 3.2.11
  • App Version: 3.2.11

Describe the bug
With a BudibaseDB, I have one table with multi file attachments field.
I have a form where I can upload up to 5 files to the database. The saving work well.
I'm able to extract the files names and urls with the help of the code in Budibase Docs (https://docs.budibase.com/docs/send-email#adding-attachments).

I send this payload to n8n (the extracted info is inserted in pieces_justificatives) :

{
  "email_demandeur": "{{trigger.fields.email_demandeur}}",
  "pieces_justificatives": "{{trigger.fields.pieces_justificatives}}"
}

Now I try to pass this information to n8n step in automation. But always got "Invalid payload JSON".
When I remove the field from the JSON payload sent to n8n, the automation is successful. When I add it back, I got the error.

To Reproduce
Steps to reproduce the behavior:

1. Go to 'Automation'
2. Add a step "App trigger"
3. Add a field "attachments" of type "string" or "array"
4. Click on 'Run test'
5. Fill the "attachments" field with this code :

const f = [{"size":479,"name":"Color Hunt Palette e7f0dc597445658147729762.png","extension":"png","key":"app_11d87e18d32947f5b7868225896acdbd/attachments/6286465c-220d-499e-9bc2-fc36f39eee19.png","url":"/files/signed/prod-budi-app-assets/app_11d87e18d32947f5b7868225896acdbd/attachments/6286465c-220d-499e-9bc2-fc36f39eee19.png?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=budibase%2F20240626%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20240626T100749Z&X-Amz-Expires=3600&X-Amz-Signature=846b15bc1518525f1826b10f6dd128265f40a3179a210832ee1b8eb04d5d2405&X-Amz-SignedHeaders=host"},{"size":2081558,"name":"unDrawCards_1718749166782_yq13p1.png","extension":"png","key":"app_11d87e18d32947f5b7868225896acdbd/attachments/d6822d2e-252f-4c39-9cb8-0a07d90a6fa5.png","url":"/files/signed/prod-budi-app-assets/app_11d87e18d32947f5b7868225896acdbd/attachments/d6822d2e-252f-4c39-9cb8-0a07d90a6fa5.png?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=budibase%2F20240626%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20240626T100749Z&X-Amz-Expires=3600&X-Amz-Signature=ed467de1e1731de0f64d067de2c75d0b9f9029e0c4cf5a0571f5d773d430b7c5&X-Amz-SignedHeaders=host"}];

const pj = f.map(p => {
    return {
      filename: p.name,
      url: p.url
    }
  })
return JSON.stringify(pj);

8. See error

Expected behavior
The automation run successfully.

• OS: Ubuntu Linux 24.01.1 LTS
• Browser : Google Chrome 131.0.6778.86 (64 bits)
• Version : Budibase 3.2.11

Additional info
I also try to directly access the “attachments” field with bindings {{ Action 3.Saved Rows.attachments }}. But I got the same result : “Invalid JSON payload”.

Anybody knows how to get this working ?

[linear[bot]]

BUDI-8875 Unable to extract multi file attachments fields from BudibaseDB for n8n automation

[andz-bb]

hey @iambricegg, I've converted this to a discussion. could you send some screenshots of your automation setup and the output for the steps please?

[iambricegg]

After a lot of tests and errors, I figure out how to make it work.

It seems that sending a payload with double quote ("...") in it mess up.

I use the following code to extract the informations (names and urls) without any quote :

const f = [
  {
    "size": 479,
    "name": "Color Hunt Palette e7f0dc597445658147729762.png",
    "extension": "png",
    "key": "app_11d87e18d32947f5b7868225896acdbd/attachments/6286465c-220d-499e-9bc2-fc36f39eee19.png",
    "url": "/files/signed/prod-budi-app-assets/app_11d87e18d32947f5b7868225896acdbd/attachments/6286465c-220d-499e-9bc2-fc36f39eee19.png?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=budibase%2F20240626%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20240626T100749Z&X-Amz-Expires=3600&X-Amz-Signature=846b15bc1518525f1826b10f6dd128265f40a3179a210832ee1b8eb04d5d2405&X-Amz-SignedHeaders=host"
  },
  {
    "size": 2081558,
    "name": "unDrawCards_1718749166782_yq13p1.png",
    "extension": "png",
    "key": "app_11d87e18d32947f5b7868225896acdbd/attachments/d6822d2e-252f-4c39-9cb8-0a07d90a6fa5.png",
    "url": "/files/signed/prod-budi-app-assets/app_11d87e18d32947f5b7868225896acdbd/attachments/d6822d2e-252f-4c39-9cb8-0a07d90a6fa5.png?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=budibase%2F20240626%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20240626T100749Z&X-Amz-Expires=3600&X-Amz-Signature=ed467de1e1731de0f64d067de2c75d0b9f9029e0c4cf5a0571f5d773d430b7c5&X-Amz-SignedHeaders=host"
  }
];

// Convert the objects into a new array with only 'name' and 'url' properties
const pj = f.map(p => {
  return {
    name: p.name,
    url: p.url
  };
});

// Custom log format to display the result without quotes
const formattedResult = pj.map(item => {
  return `{name: ${item.name}, url: ${item.url}}`;
}).join(',');

return (`[${formattedResult}]`);

This code produce a result like this :

[
  {
    name: Color Hunt Palette e7f0dc597445658147729762.png, 
    url: /files/signed/prod-budi-app-assets/app_11d87e18d32947f5b7868225896acdbd/attachments/6286465c-220d-499e-9bc2-fc36f39eee19.png?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=budibase%2F20240626%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20240626T100749Z&X-Amz-Expires=3600&X-Amz-Signature=846b15bc1518525f1826b10f6dd128265f40a3179a210832ee1b8eb04d5d2405&X-Amz-SignedHeaders=host
  },
  {
    name: unDrawCards_1718749166782_yq13p1.png, 
    url: /files/signed/prod-budi-app-assets/app_11d87e18d32947f5b7868225896acdbd/attachments/d6822d2e-252f-4c39-9cb8-0a07d90a6fa5.png?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Credential=budibase%2F20240626%2Fus-east-1%2Fs3%2Faws4_request&X-Amz-Date=20240626T100749Z&X-Amz-Expires=3600&X-Amz-Signature=ed467de1e1731de0f64d067de2c75d0b9f9029e0c4cf5a0571f5d773d430b7c5&X-Amz-SignedHeaders=host
  }
]

And finally, I pass that extracted array to the n8n payload :
I send this payload to n8n (the extracted info is inserted in pieces_justificatives) :

{
  "email_demandeur": "{{trigger.fields.email_demandeur}}",
  "pieces_justificatives": "{{trigger.fields.pieces_justificatives}}"
}