blob: 90c6016db1c9838f800f45d96249751c4f1d4080 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
|
# Braid Middleware Design
**Goal**: Implement HTTP Keep-Alive mechanism for Braid updates to support real-time streams.
## Current State
`Network/Wai/Middleware/Braid.hs` implements the Braid protocol headers but lacks a robust mechanism to keep the connection open and push updates.
## Design Requirements
1. **Connection Management**:
- Identify Braid subscriptions via headers.
- Keep the response body open (streaming response).
- Handle client disconnects gracefully.
2. **Update Channel**:
- Use a `TChan` or `BroadcastChan` to signal updates to the connection handler.
- When a resource changes, push a new Braid frame to the open stream.
3. **Frame Format**:
- Adhere to Braid spec for patch frames.
- `Content-Type: application/json` (or relevant type).
- `Merge-Type: braid`.
## Implementation Plan
1. Modify middleware to hijack response for Braid requests.
2. Spawn a lightweight thread to listen on an update channel.
3. Stream chunks to the client.
|
