a75cbcd224
Node flags (cmd/node/main.go):
--max-cpu / --max-ram-mb — Go runtime caps (GOMAXPROCS / GOMEMLIMIT)
--feed-disk-limit-mb — hard 507 refusal for new post bodies over quota
--chain-disk-limit-mb — advisory watcher (can't reject blocks without
breaking consensus; logs WARN every minute)
Client — Saved Messages (self-chat):
- Auto-created on sign-in, pinned top of chat list, blue bookmark avatar
- Send short-circuits the relay (no encrypt, no fee, no mailbox hop)
- Empty state rendered outside inverted FlatList — fixes the mirrored
"say hi…" on Android RTL-aware layout builds
- PostCard shows "You" for own posts instead of the self-contact alias
Client — user walls:
- New route /(app)/feed/author/[pub] with infinite-scroll via
`created_at` cursor and pull-to-refresh
- Profile screen gains "View posts" button (universal) next to
"Open chat" (contact-only)
Feed pipeline:
- Bump client JPEG quality 0.5 → 0.75 to match server scrubber (Q=75),
so a 60 KiB compose doesn't balloon past 256 KiB after server re-encode
- ErrPostTooLarge now wraps with the actual size vs cap, errors.Is
preserved in the HTTP layer
- FeedMailbox quota + DiskUsage surface — supports new CLI flag
README:
- Step-by-step "first node / joiner" section on the landing page,
full flag tables incl. the new resource-cap group, minimal
checklists for open/private/low-end deployments
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.