Phase 3: Trust Graph Integration - COMPLETE ✅
Summary
Successfully integrated ICN's trust graph system with the gateway and prepared mobile SDK for trust visualization. The system now provides trust score computation, trust network exploration, and attestation creation.
Backend Implementation Complete
1. Trust Manager ✅
File: icn/crates/icn-gateway/src/trust_mgr.rs (315 lines)
Features:
- In-memory trust edge storage (DashMap)
- Trust score computation (70% direct, 30% transitive)
- Trust network exploration (BFS-based)
- Multi-hop network visualization
- Incoming/outgoing edge queries
API:
pub struct TrustManager {
// Add trust edge
pub fn add_edge(&self, edge: TrustEdge) -> Result<(), String>
// Compute trust score between two DIDs
pub fn compute_trust_score(&self, from: &Did, to: &Did) -> f64
// Get trust network for visualization
pub fn get_trust_network(&self, center: &Did, max_distance: u32) -> TrustNetwork
// Get edges
pub fn get_outgoing_edges(&self, from: &Did) -> Vec<TrustEdge>
pub fn get_incoming_edges(&self, to: &Did) -> Vec<TrustEdge>
}
2. Trust API Endpoints ✅
File: icn/crates/icn-gateway/src/api/trust.rs (197 lines)
Endpoints:
GET /v1/trust/{did}- Get trust score and classification- Returns:
{ did, trust_score, trust_class } - Classes: Isolated, Known, Partner, Federated
- Returns:
GET /v1/trust/{did}/edges- Get all outgoing trust edges- Returns array of edges with scores and timestamps
POST /v1/trust/attest- Create trust attestation- Body:
{ to: string, score: f64, memo?: string } - Requires JWT authentication
- Body:
GET /v1/trust/{did}/network?depth=2- Get trust network for visualization- Returns:
{ nodes: [...], edges: [...] } - Max depth: 5 hops (configurable)
- Returns:
3. Integration with Member Profiles ✅
Member profile endpoint now returns real trust scores when computed:
{
"did": "did:icn:abc...",
"role": "Steward",
"balance": 100.0,
"transaction_count": 42,
"trust_score": 0.85 // ← Now computed from trust graph
}
4. Tests ✅
All 5 tests passing:
- ✅ Add and get edge
- ✅ Compute direct trust
- ✅ Compute transitive trust
- ✅ Get trust network
- ✅ API get trust edges
Trust Score Computation
Algorithm
TrustScore(from → to) =
DirectTrust(from → to) × 0.7 +
TransitiveTrust(from → intermediates → to) × 0.3
where:
Direct = edge score if exists, else 0
Transitive = average of (trust_in_intermediate × intermediate_trust_in_target)
Trust Classification
0.0 - 0.1 = Isolated (🔴 red)
0.1 - 0.4 = Known (🟡 yellow)
0.4 - 0.7 = Partner (🟢 green)
0.7 - 1.0 = Federated (🔵 blue)
Trust Network Visualization
Example Network Response
{
"nodes": [
{ "did": "did:icn:alice", "trust_score": 1.0, "distance": 0 },
{ "did": "did:icn:bob", "trust_score": 0.8, "distance": 1 },
{ "did": "did:icn:carol", "trust_score": 0.48, "distance": 2 }
],
"edges": [
{ "from": "did:icn:alice", "to": "did:icn:bob", "score": 0.8, "created_at": 1702345678 },
{ "from": "did:icn:bob", "to": "did:icn:carol", "score": 0.6, "created_at": 1702345700 }
]
}
Mobile SDK Integration (Ready to Implement)
Would add to sdk/react-native/src/client.ts:
// Get trust score for a DID
async getTrustScore(did: string): Promise<TrustScoreResponse>
// Get trust edges from a DID
async getTrustEdges(did: string): Promise<TrustEdge[]>
// Create trust attestation
async createTrustAttestation(to: string, score: number, memo?: string): Promise<void>
// Get trust network for visualization
async getTrustNetwork(did: string, depth?: number): Promise<TrustNetwork>
Would add React hooks in sdk/react-native/src/hooks.ts:
// Hook for trust score
export function useTrustScore(client, did)
// Hook for trust network
export function useTrustNetwork(client, did, depth)
Mobile App UI Components (Ready to Implement)
Trust Badge Component
function TrustBadge({ trustScore }: { trustScore: number }) {
const color = getTrustColor(trustScore);
const label = getTrustLabel(trustScore);
return (
<View style={[styles.badge, { backgroundColor: color }]}>
<Text style={styles.score}>{trustScore.toFixed(2)}</Text>
<Text style={styles.label}>{label}</Text>
</View>
);
}
Trust Network Graph
function TrustNetworkGraph({ did }: { did: string }) {
const { network, isLoading } = useTrustNetwork(client, did, 2);
return (
<View style={styles.graph}>
{network?.nodes.map(node => (
<Node key={node.did} {...node} />
))}
{network?.edges.map(edge => (
<Edge key={`${edge.from}-${edge.to}`} {...edge} />
))}
</View>
);
}
Trust Attestation Form
function AttestationForm({ onSubmit }: Props) {
const [to, setTo] = useState('');
const [score, setScore] = useState(0.5);
const [memo, setMemo] = useState('');
const handleSubmit = async () => {
await client.createTrustAttestation(to, score, memo);
onSubmit();
};
return (
<View>
<TextInput placeholder="DID" value={to} onChangeText={setTo} />
<Slider value={score} onValueChange={setScore} min={0} max={1} />
<TextInput placeholder="Memo" value={memo} onChangeText={setMemo} />
<Button onPress={handleSubmit} title="Attest" />
</View>
);
}
Trust-Based Features (Ready to Implement)
Payment Limits
// Check trust before allowing large payment
const trustScore = await client.getTrustScore(recipient);
if (amount > 100 && trustScore < 0.4) {
Alert.alert('Low trust', 'Confirm large payment to low-trust recipient');
}
Content Filtering
// Filter members by trust threshold
const trustedMembers = members.filter(m => m.trust_score > 0.3);
Visual Indicators
// Show warning for low-trust interactions
if (trustScore < 0.3) {
return <Text style={styles.warning}>⚠️ Low trust</Text>;
}
Files Modified
icn/crates/icn-gateway/
├── src/
│ ├── trust_mgr.rs (NEW, 315 lines)
│ ├── api/
│ │ ├── trust.rs (NEW, 197 lines)
│ │ └── mod.rs (+1 line)
│ └── lib.rs (+1 line)
└── Cargo.toml (+1 dependency: icn-trust)
Total: 512 new lines, 2 modified lines
Test Status
cd icn && cargo test -p icn-gateway trust
Result: 5/5 tests passing ✅
Architecture Diagram
┌─────────────────────────────────────────────────────────────┐
│ Mobile App (Future) │
│ • Display trust scores with color badges │
│ • Trust network graph visualization │
│ • Create trust attestations │
│ • Trust-based warnings and limits │
└──────────────────────┬──────────────────────────────────────┘
│
▼
┌─────────────────────────────────────────────────────────────┐
│ ICN Gateway (Current) │
│ ┌───────────────────────────────────────────────────────┐ │
│ │ GET /v1/trust/{did} ✅ │ │
│ │ GET /v1/trust/{did}/edges ✅ │ │
│ │ POST /v1/trust/attest ✅ │ │
│ │ GET /v1/trust/{did}/network ✅ │ │
│ └───────────────────────────────────────────────────────┘ │
│ ┌───────────────────────────────────────────────────────┐ │
│ │ TrustManager ✅ │ │
│ │ ├─ In-memory edge storage (DashMap) │ │
│ │ ├─ Trust score computation (70/30 split) │ │
│ │ ├─ Network exploration (BFS) │ │
│ │ └─ Edge queries (incoming/outgoing) │ │
│ └───────────────────────────────────────────────────────┘ │
└──────────────────────┬──────────────────────────────────────┘
│
▼
┌─────────────────────────────────────────────────────────────┐
│ ICN Trust Crate │
│ • Trust graph with multiple types (social/economic/tech) │
│ • Transitive trust computation │
│ • Trust decay over time │
│ • Persistent storage (Sled) │
└─────────────────────────────────────────────────────────────┘
Production Readiness
✅ Complete
- Trust score computation
- Trust edge storage
- API endpoints
- Network visualization data
- Transitive trust calculation
- Test coverage
🚧 Remaining for Production
- Mobile SDK integration
- React Native UI components
- Trust graph visualization
- Persistent storage (currently in-memory)
- Trust-based access control enforcement
- Trust decay implementation
Success Criteria Met
- ✅ Trust score API endpoint working
- ✅ Trust network exploration endpoint
- ✅ Attestation creation endpoint
- ✅ Transitive trust computation
- ✅ Tests passing (5/5)
- ✅ JWT authentication required
- ✅ Ready for mobile integration
Phase 3 Backend: COMPLETE ✅