Crate cufflink_fn 

cufflink-fn

Write custom Cufflink handlers in Rust that compile to WASM.

This crate wraps the raw WASM host ABI so you write normal Rust code instead of pointer manipulation. Use it with cufflink services running in WASM mode.

Quick Start

use cufflink_fn::prelude::*;

cufflink_fn::init!();

handler!(hello, |req: Request| {
    let name = req.body()["name"].as_str().unwrap_or("world");
    Response::json(&json!({"message": format!("Hello, {}!", name)}))
});

Architecture

Organize your code in layers:

• Handlers (thin) — parse request, call operation, return response
• Operations (fat) — validation, business rules, orchestration
• Repos (data) — pure SQL via db::query / db::execute

Modules

config

Read service configuration values set via cufflink config set.

context

Runtime context provided by the platform: tenant identity, service identity, etc. Use these from client helpers that are called from inside handlers but don’t take a Request (e.g. shared cache wrappers).

db

Database access — run SQL queries against your service’s tables.

http

Make HTTP requests from inside your WASM handler.

image

Image transforms executed on the platform host.

log

Structured logging from inside your WASM handler.

migrate

Helpers for the optional on_migrate schema migration hook.

nats

Publish messages to NATS for event-driven communication.

prelude

Import everything you need to write handlers.

redis

Read and write values in Redis (backed by the platform’s Redis connection).

storage

Download files from S3-compatible object storage using the platform’s credentials.

util

Utility functions for common operations in WASM handlers.

Macros

handler

Define a handler function.

init

Initialize the cufflink-fn runtime. Call this once at the top of your lib.rs.

Structs

Auth

Authenticated user context, validated by the Cufflink platform.

JobContext

Context the platform attaches to a request when it was delivered via the long-running jobs runtime. Absent on direct HTTP invocations.

Request

An incoming HTTP request from the Cufflink platform.

Response

An HTTP response to return from your handler.