React Token

This token represents a reaction created by a user.

The react token must not contain a content (c) field. The token must contain a subject (sub) field which points to the action being reacted to. For other constraints see the Action Tokens.

Content-Addressing

This token is content-addressed using SHA-256:

• The entire JWT token (header + payload + signature) is hashed
• Action ID format: a1~{base64_hash}
• Changing any field invalidates the action_id
• See Content-Addressing & Merkle Trees for details

Immutability: Once created, a REACT token cannot be modified without changing its action ID.

Subject Reference

The sub (subject) field references the action being reacted to:

• Contains the target action’s action_id (a1~...)
• Target action must exist and be verified
• Creates a non-hierarchical reference (reactions don’t create visible threading)
• Cannot modify subject without breaking reference

Why Subject Instead of Parent:

• parent (p) is used for hierarchical threading (comments create visible child hierarchy)
• subject (sub) is used for non-hierarchical references (reactions reference without creating hierarchy)
• Reactions don’t create visible child actions in the timeline
• This semantic distinction keeps threading clean

Properties:

• Subject references are immutable
• Cannot change which post you’re reacting to
• Merkle tree ensures subject hasn’t been tampered with
• Federation: remote instances can verify the complete reference

Database Key

The database key for a react token is {type}:{sub}:{iss}

Purpose: This key ensures that a user can only have one active reaction of each type to a specific action. The key components are:

• {type}: Full type including subtype (e.g., “REACT:LIKE”)
• {sub}: Subject ID (what they’re reacting to)
• {iss}: Issuer identity (who is reacting)

Example:

• Alice LIKEs a post → Stored with key REACT:LIKE:a1~post123:alice.example.com
• Alice changes to LOVE → New LOVE token, previous LIKE is marked deleted
• Only ONE reaction of each type per user per post
• Changing reaction type creates a new action but invalidates the previous one

Audience Resolution

The aud (audience) field is automatically resolved from the subject action:

• Set to the issuer of the subject action (the post owner)
• Ensures the reaction notification reaches the content creator
• Does not need to be explicitly provided when creating the reaction

Example

User @someotheruser.cloudillo.net likes a post:

Subtypes

REACT tokens use subtypes to indicate the reaction type:

See Also

• Post Token - Creating content that can receive reactions
• Comment Token - Comments use parent for threading (different from reactions)
• Actions & Action Tokens - Overview of the action token system