6425b5cffb
Server pagination
- blockchain.PostsByAuthor signature extended with beforeTs int64;
passing 0 keeps the previous "everything, newest first" behaviour,
non-zero skips posts with CreatedAt >= beforeTs so clients can
paginate older results.
- node.FeedConfig.PostsByAuthor callback type updated; the two
/feed endpoints that use it (timeline + author) now accept
`?before=<unix_seconds>` and forward it through. /feed/author
limit default dropped from 50 to 30 to match the client's page
size.
- node/api_common.go: new queryInt64 helper for parsing the cursor
param safely (matches the queryInt pattern already used).
Client infinite scroll (Feed tab)
- lib/feed.ts: fetchTimeline / fetchAuthorPosts accept
`{limit?, before?}` options. Old signatures still work for other
callers (fetchForYou / fetchTrending / fetchHashtag) — those are
ranked feeds that don't have a stable cursor so they stay
single-shot.
- feed/index.tsx: tracks loadingMore / exhausted state. onEndReached
(threshold 0.6) fires loadMore() which fetches the next 20 posts
using the oldest currently-loaded post's created_at as `before`.
Deduplicates on post_id before appending. Stops when the server
returns < PAGE_SIZE items. ListFooterComponent shows a small
spinner during paginated fetches.
- FlatList lazy-render tuning on all feed lists (index + hashtag):
initialNumToRender:10, maxToRenderPerBatch:8, windowSize:7,
removeClippedSubviews — first paint stays quick even with 100+
posts loaded.
Chat lazy render
- chats/[id].tsx FlatList: initialNumToRender:25 (~1.5 screens),
maxToRenderPerBatch:12, windowSize:10, removeClippedSubviews.
Keeps initial chat open snappy on conversations with thousands
of messages; RN re-renders a small window around the viewport
and drops the rest.
Tests
- chain_test.go updated for new PostsByAuthor signature.
- All 7 Go packages green.
- tsc --noEmit clean.
Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>
DChain Messenger — React Native Client
E2E-encrypted mobile/desktop messenger built on the DChain blockchain stack.
Stack: React Native · Expo · NativeWind (Tailwind) · TweetNaCl · Zustand
Quick Start
cd client-app
npm install
npx expo start # opens Expo Dev Tools
# Press 'i' for iOS simulator, 'a' for Android, 'w' for web
Requirements
- Node.js 18+
- Expo Go on your phone (for Expo tunnel), or iOS/Android emulator
- A running DChain node (see root README for
docker compose up --build -d)
Project Structure
client-app/
├── app/
│ ├── _layout.tsx # Root layout — loads keys, sets up nav
│ ├── index.tsx # Welcome / onboarding
│ ├── (auth)/
│ │ ├── create.tsx # Generate new Ed25519 + X25519 keys
│ │ ├── created.tsx # Key created — export reminder
│ │ └── import.tsx # Import existing key.json
│ └── (app)/
│ ├── _layout.tsx # Tab bar — Chats · Wallet · Settings
│ ├── chats/
│ │ ├── index.tsx # Chat list with contacts
│ │ └── [id].tsx # Individual chat with E2E encryption
│ ├── requests.tsx # Incoming contact requests
│ ├── new-contact.tsx # Add contact by @username or address
│ ├── wallet.tsx # Balance + TX history + send
│ └── settings.tsx # Node URL, key export, profile
├── components/ui/ # shadcn-style components (Button, Card, Input…)
├── hooks/
│ ├── useMessages.ts # Poll relay inbox, decrypt messages
│ ├── useBalance.ts # Poll token balance
│ └── useContacts.ts # Load contacts + poll contact requests
└── lib/
├── api.ts # REST client for all DChain endpoints
├── crypto.ts # NaCl box encrypt/decrypt, Ed25519 sign
├── storage.ts # SecureStore (keys) + AsyncStorage (data)
├── store.ts # Zustand global state
├── types.ts # TypeScript interfaces
└── utils.ts # cn(), formatAmount(), relativeTime()
Cryptography
| Operation | Algorithm | Library |
|---|---|---|
| Transaction signing | Ed25519 | TweetNaCl sign |
| Key exchange | X25519 (Curve25519) | TweetNaCl box |
| Message encryption | NaCl box (XSalsa20-Poly1305) | TweetNaCl box |
| Key storage | Device secure enclave | expo-secure-store |
Messages are encrypted as:
Envelope {
sender_pub: <X25519 hex> // sender's public key
recipient_pub: <X25519 hex> // recipient's public key
nonce: <24-byte hex> // random per message
ciphertext: <hex> // NaCl box(plaintext, nonce, sender_priv, recipient_pub)
}
Connect to your node
- Start the DChain node:
docker compose up --build -d - Open the app → Settings → Node URL →
http://YOUR_IP:8081 - If using Expo Go on physical device: your PC and phone must be on the same network, or use
npx expo start --tunnel
Key File Format
The key.json exported/imported by the app:
{
"pub_key": "26018d40...", // Ed25519 public key (64 hex chars)
"priv_key": "...", // Ed25519 private key (128 hex chars)
"x25519_pub": "...", // X25519 public key (64 hex chars)
"x25519_priv": "..." // X25519 private key (64 hex chars)
}
This is the same format as the Go node's --key flag.