Kāru

A Go package for forum and comment system logic, agnostic of the consuming application.

Features

• Dual database: PostgreSQL via pgx and SQLite via modernc.org/sqlite
• Hierarchical paths: Organise content under arbitrary paths (e.g. forum/general, blog/post-123, gallery/image-456)
• Flexible permissions: Permission groups with codes (r read, w post, d delete own, D delete any, t delete thread, l lock/unlock, m move)
• Path-inherited permissions: Strictest permission across all matching path levels applies
• Silent denial: Paths and posts without access are invisible
• Threaded replies: Full nesting of posts via parent_id
• User preferences: Per-user key-value storage for filtering and settings
• Search: Title and content search across posts
• No account system: The consuming application handles authentication and passes user IDs and permission strings with each API call

Usage

import "github.com/grimdork/karu"

k, err := karu.New("sqlite", "file::memory:?cache=shared")
if err != nil { /* handle */ }
defer k.Close()

ctx := context.Background()
if err := k.Migrate(ctx); err != nil { /* handle */ }

post, err := k.CreateThread(ctx, "general", "user1",
    "Hello World", "First post!", "general:rwd")
if err != nil { /* handle */ }

reply, err := k.CreatePost(ctx, post.ID, "user2",
    "Nice reply", "general:rwd")
if err != nil { /* handle */ }

Permission strings

Format: keyword:code[,keyword:code]*

Example: general:rwdDtlm,moderators:rw

Permission codes:

Code	Meaning
r	Read posts
w	Create posts/replies
d	Delete own posts
D	Delete any post
t	Delete threads
l	Lock/unlock threads
m	Move threads/posts

Permission evaluation walks from the most specific path to root and takes the intersection of all matching groups.