Pubky.app Data Model Specification

Version 0.2.1

⚠️ Warning: Rapid Development Phase
This specification is in an early development phase and is evolving quickly. Expect frequent changes and updates as the system matures. Consider this a v0 draft.

When we reach the first stable, long-term support version of the schemas, paths will adopt the format: pubky.app/v1/ to indicate compatibility and stability.

Table of Contents

1. Introduction
2. Quick Start
3. Data Models
   • PubkyAppUser
   • PubkyAppFile
   • PubkyAppPost
   • PubkyAppTag
   • PubkyAppBookmark
   • PubkyAppFollow
   • PubkyAppMute
   • PubkyAppFeed
   • PubkyAppLastRead
4. Validation Rules
   • Common Rules
   • ID Generation
5. Glossary
6. Examples
   • PubkyAppUser
   • PubkyAppPost
   • PubkyAppTag
7. License

---

Introduction

This document specifies the data models and validation rules for the Pubky.app clients interactions. It defines the structure of data entities, their properties, and the validation rules to ensure data integrity and consistency. This is intended for developers building compatible libraries or clients.

This document intents to be a faithful representation of our Rust pubky.app models. If you intend to develop in Rust, use them directly. In case of disagreement between this document and the Rust implementation, the Rust implementation prevails.

---

Quick Start

Pubky.app models are designed for decentralized content sharing. The system uses a combination of timestamp-based IDs and Blake3-hashed IDs encoded in Crockford Base32 to ensure unique identifiers for each entity.

Concepts:

• Timestamp IDs for sequential objects like posts and files.
• Hash IDs for content-based uniqueness (e.g., tags and bookmarks).
• Validation Rules ensure consistent and interoperable data formats.

---

Data Models

PubkyAppUser

Description: Represents a user's profile information.

URI: /pub/pubky.app/profile.json

Field	Type	Description	Validation Rules
name	String	User's name.	Required. Length: 3–50 characters. Cannot be "[DELETED]".
bio	String	Short biography.	Optional. Maximum length: 160 characters.
image	String	URL to the user's profile image.	Optional. Valid URL. Maximum length: 300 characters.
links	Array	List of associated links (title + URL).	Optional. Maximum of 5 links, each with title (100 chars max) and valid URL (300 chars max).
status	String	User's current status.	Optional. Maximum length: 50 characters.

Validation Notes:

• Reserved keyword [DELETED] cannot be used for name.
• Each UserLink in links must have a valid title and URL.

Example: Valid User

{
  "name": "Alice",
  "bio": "Toxic maximalist.",
  "image": "pubky://user_id/pub/pubky.app/files/0000000000000",
  "links": [
    {
      "title": "GitHub",
      "url": "https://github.com/alice"
    }
  ],
  "status": "Exploring decentralized tech."
}

---

PubkyAppFile

Description: Represents metadata of file uploaded by the user.

URI: /pub/pubky.app/files/:file_id

Field	Type	Description	Validation Rules
name	String	Name of the file.	Required.
created_at	Integer	Unix timestamp of creation.	Required.
src	String	File blob URL	Required.
content_type	String	MIME type of the file.	Required.
size	Integer	Size of the file in bytes.	Required. Positive integer.

Validation Notes:

• The file_id in the URI must be a valid Timestamp ID.

---

PubkyAppPost

Description: Represents a user's post.

URI: /pub/pubky.app/posts/:post_id

Field	Type	Description	Validation Rules
content	String	Content of the post.	Required. Max length: 1000 (short), 50000 (long). Cannot be "[DELETED]".
kind	String	Type of post.	Required. Must be a valid PubkyAppPostKind value.
parent	String	URI of the parent post (if a reply).	Optional. Must be a valid URI if present.
embed	Object	Embedded content (type + URI).	Optional. URI must be valid if present.
attachments	Array	List of attachment URIs.	Optional. Each must be a valid URI.

Post Kinds:

• short
• long
• image
• video
• link
• file

Example: Valid Post

{
  "content": "Hello world! This is my first post.",
  "kind": "short",
  "parent": null,
  "embed": {
    "kind": "short",
    "uri": "pubky://user_id/pub/pubky.app/posts/0000000000000"
  },
  "attachments": ["pubky://user_id/pub/pubky.app/files/0000000000000"]
}

---

PubkyAppTag

Description: Represents a tag applied to a URI.

URI: /pub/pubky.app/tags/:tag_id

Field	Type	Description	Validation Rules
uri	String	URI of the tagged object.	Required. Must be a valid URI.
label	String	Label for the tag.	Required. Trimmed, lowercase. Max length: 20 characters.
created_at	Integer	Unix timestamp of creation.	Required.

Validation Notes:

• The tag_id is a Hash ID derived from the uri and label.

---

PubkyAppBookmark

Description: Represents a bookmark to a URI.

URI: /pub/pubky.app/bookmarks/:bookmark_id

Field	Type	Description	Validation Rules
uri	String	URI of the bookmark.	Required. Must be a valid URI.
created_at	Integer	Timestamp of creation.	Required.

Validation Notes:

• The bookmark_id is a Hash ID derived from the uri.

---

PubkyAppFollow

Description: Represents a follow relationship.

URI: /pub/pubky.app/follows/:user_id

Field	Type	Description	Validation Rules
created_at	Integer	Timestamp of creation.	Required.

---

PubkyAppFeed

Description: Represents a feed configuration.

URI: /pub/pubky.app/feeds/:feed_id

Field	Type	Description	Validation Rules
tags	Array	List of tags for filtering.	Optional. Strings must be trimmed.
reach	String	Feed visibility (e.g., all, friends).	Required. Must be a valid reach.
layout	String	Feed layout style (e.g., columns).	Required. Must be valid layout.
sort	String	Sort order (e.g., recent).	Required. Must be valid sort.
content	String	Type of content filtered.	Optional.
name	String	Name of the feed.	Required.

---

Validation Rules

Common Rules

1. Timestamp IDs: 13-character Crockford Base32 strings derived from timestamps (in microseconds).
2. Hash IDs: First half of the bytes from the resulting Blake3-hashed strings encoded in Crockford Base32.
3. URLs: All URLs must pass standard validation.

---

License

This specification is released under the MIT License.