madbase/WASI_DENO.md

Plan: Deno Compatibility for MadBase Edge Functions

Problem Statement

Currently, MadBase executes Edge Functions as WASM modules via wasmtime. Supabase-compatible Edge Functions (like those in accountaflow) are written in TypeScript and target a Deno environment. Migrating these requires 1:1 compatibility for the Deno namespace, ES modules, and standard web APIs (Fetch, Request, Response).

Proposed Architecture

1. Dual-Runtime Strategy

Extend the functions crate to support two runtimes:

• WasmRuntime: Existing wasmtime based executor for compiled modules.
• DenoRuntime: A new V8-based executor utilizing deno_core and deno_runtime.

2. Runtime Detection

The gateway should detect the function type:

• DenoRuntime (V8): Files ending in .ts or .js. Recommended for standard Edge Functions due to JIT-optimized performance.
• WasmRuntime (Wasmtime): Native WASM binaries (Rust, Go, C++). Best for specialized, high-performance logic or pre-compiled modules.

Implementation Steps

Phase 1: Core Integration

• Add deno_core and deno_runtime dependencies to madbase/functions/Cargo.toml.
• Create functions/src/deno_runtime.rs.
• Implement execute_script(code: String, payload: Value) using JsRuntime.

Phase 2: Supabase Environment Compatibility

• Process Environment: Inject SUPABASE_URL, SUPABASE_ANON_KEY, and SUPABASE_SERVICE_ROLE_KEY.
• Global Objects: Implement a shim for Deno.serve to capture the incoming request and route it to the script's handler.
• Header Parsing: Ensure standard headers (apikey, Authorization) are passed through.

Phase 3: Module Resolution

• Implement a ModuleLoader that handles imports from https://esm.sh/.
• Support local imports from a shared functions directory (like _shared).

API Changes

Gateway

Modify POST /functions/v1 to accept type: "typescript" | "wasm". Default to "typescript" for source code.

Deployment Table

Update the functions table schema in the control plane to store the runtime type.

Verification Plan

Automated Tests

1. Hello World Test: Deploy a simple .ts function and verify the output.
2. Supabase Client Test: Deploy a function that imports @supabase/supabase-js from esm.sh and queries the MadBase Data API.
3. Environment Variable Test: Verify Deno.env.get returns expected MadBase configuration.

Manual Verification

1. Attempt to deploy the invite-staff function from accountaflow directly to MadBase.
2. Verify cross-organization invitation logic works.