compliance: compliance-server: Fallback to chainalysis API if not cached

Cargo.toml

@@ -29,3 +29,6 @@ renegade-circuits = { package = "circuits", git = "https://github.com/renegade-f
 renegade-circuit-types = { package = "circuit-types", git = "https://github.com/renegade-fi/renegade.git" }
 renegade-crypto = { git = "https://github.com/renegade-fi/renegade.git" }
 renegade-util = { package = "util", git = "https://github.com/renegade-fi/renegade.git" }
+
+# === Misc Dependencies === #
+tracing = "0.1"

compliance/compliance-api/src/lib.rs

@@ -8,6 +8,9 @@
 
 use serde::{Deserialize, Serialize};
 
+/// The API endpoint for screening an address for compliance
+pub const WALLET_SCREEN_PATH: &str = "/v0/check-compliance";
+
 /// The response type for a compliance check
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct ComplianceCheckResponse {

compliance/compliance-server/Cargo.toml

@@ -17,4 +17,8 @@ renegade-util = { workspace = true }
 
 # === Misc === #
 clap = { version = "4.5", features = ["derive"] }
+reqwest = { version = "0.12", features = ["json"] }
+serde = { version = "1.0", features = ["derive"] }
+serde_json = "1.0"
 tokio = { version = "1.37", features = ["full"] }
+tracing = { workspace = true }

compliance/compliance-server/migrations/2024-06-28-231756_create_compliance_table/up.sql

@@ -2,6 +2,7 @@
 CREATE TABLE IF NOT EXISTS wallet_compliance (
     address TEXT PRIMARY KEY,
     is_compliant BOOLEAN NOT NULL,
+    risk_level TEXT NOT NULL,
     reason TEXT NOT NULL,
     created_at TIMESTAMP NOT NULL DEFAULT NOW(),
     expires_at TIMESTAMP NOT NULL DEFAULT NOW() + INTERVAL '1 year'

compliance/compliance-server/src/chainalysis_api.rs

@@ -0,0 +1,107 @@
+//! Helpers for interacting with the chainalysis API
+
+use serde::{Deserialize, Serialize};
+use tracing::warn;
+
+use crate::{db::ComplianceEntry, error::ComplianceServerError};
+
+// -------------
+// | API Types |
+// -------------
+
+/// The base URL for the chainalysis entities API
+const CHAINALYSIS_API_BASE: &str = "https://api.chainalysis.com/api/risk/v2/entities";
+/// The header name for the auth token
+const TOKEN_HEADER: &str = "Token";
+
+/// The register address request body
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct RegisterAddressRequest {
+    /// The address to register
+    pub address: String,
+}
+
+/// The response to a risk assessment query
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct RiskAssessmentResponse {
+    /// The address that the assessment is for
+    pub address: String,
+    /// The risk assessment status
+    pub risk: String,
+    /// The reason for the risk assessment
+    #[serde(rename = "riskReason")]
+    pub risk_reason: Option<String>,
+}
+
+impl RiskAssessmentResponse {
+    /// Get a compliance entry from the risk assessment
+    pub fn as_compliance_entry(self) -> ComplianceEntry {
+        // We allow low and medium risk entries, high and severe are marked
+        // non-compliant
+        let compliant = match self.risk.as_str() {
+            "Low" | "Medium" => true,
+            "High" | "Severe" => false,
+            x => {
+                // For now we don't block on an unknown assessment, this should be unreachable
+                warn!("Unexpected risk assessment: {x}");
+                true
+            },
+        };
+
+        let risk_reason = self.risk_reason.unwrap_or_default();
+        ComplianceEntry::new(self.address, compliant, self.risk, risk_reason)
+    }
+}
+
+// ---------------
+// | Client Impl |
+// ---------------
+
+/// Query chainalysis for the compliance status of a wallet
+pub async fn query_chainalysis(
+    wallet_address: &str,
+    chainalysis_api_key: &str,
+) -> Result<ComplianceEntry, ComplianceServerError> {
+    // 1. Register the wallet
+    register_addr(wallet_address, chainalysis_api_key).await?;
+
+    // 2. Query the risk assessment
+    let risk_assessment = query_risk_assessment(wallet_address, chainalysis_api_key).await?;
+    Ok(risk_assessment.as_compliance_entry())
+}
+
+/// Register a wallet with chainalysis
+async fn register_addr(
+    wallet_address: &str,
+    chainalysis_api_key: &str,
+) -> Result<(), ComplianceServerError> {
+    let body = RegisterAddressRequest { address: wallet_address.to_string() };
+    let client = reqwest::Client::new();
+    client
+        .post(CHAINALYSIS_API_BASE)
+        .header(TOKEN_HEADER, chainalysis_api_key)
+        .json(&body)
+        .send()
+        .await?
+        .error_for_status()?;
+
+    Ok(())
+}
+
+/// Query the risk assessment from chainalysis
+async fn query_risk_assessment(
+    wallet_address: &str,
+    chainalysis_api_key: &str,
+) -> Result<RiskAssessmentResponse, ComplianceServerError> {
+    let url = format!("{CHAINALYSIS_API_BASE}/{wallet_address}");
+    let client = reqwest::Client::new();
+    let resp = client
+        .get(url)
+        .header(TOKEN_HEADER, chainalysis_api_key)
+        .send()
+        .await?
+        .error_for_status()?;
+
+    let risk_assessment: RiskAssessmentResponse = resp.json().await?;
+    Ok(risk_assessment)
+}

compliance/compliance-server/src/db.rs

@@ -1,6 +1,6 @@
 //! Database helpers for the server
 
-use std::time::SystemTime;
+use std::time::{Duration, SystemTime};
 
 use compliance_api::ComplianceStatus;
 use diesel::{ExpressionMethods, Insertable, PgConnection, QueryDsl, Queryable, RunQueryDsl};
@@ -14,6 +14,9 @@ use crate::{
     },
 };
 
+/// The default expiration duration for a compliance entry
+const DEFAULT_EXPIRATION_DURATION: Duration = Duration::from_days(365);
+
 // ----------
 // | Models |
 // ----------
@@ -25,12 +28,20 @@ use crate::{
 pub struct ComplianceEntry {
     pub address: String,
     pub is_compliant: bool,
+    pub risk_level: String,
     pub reason: String,
     pub created_at: SystemTime,
     pub expires_at: SystemTime,
 }
 
 impl ComplianceEntry {
+    /// Create a new entry from a risk assessment
+    pub fn new(address: String, is_compliant: bool, risk_level: String, reason: String) -> Self {
+        let created_at = SystemTime::now();
+        let expires_at = created_at + DEFAULT_EXPIRATION_DURATION;
+        ComplianceEntry { address, is_compliant, risk_level, reason, created_at, expires_at }
+    }
+
     /// Get the compliance status for an entry
     pub fn compliance_status(&self) -> ComplianceStatus {
         if self.is_compliant {
@@ -57,3 +68,16 @@ pub fn get_compliance_entry(
 
     Ok(query.first().cloned())
 }
+
+/// Insert a compliance entry into the database
+pub fn insert_compliance_entry(
+    entry: ComplianceEntry,
+    conn: &mut PgConnection,
+) -> Result<(), ComplianceServerError> {
+    diesel::insert_into(compliance_table)
+        .values(entry)
+        .execute(conn)
+        .map_err(err_str!(ComplianceServerError::Db))?;
+
+    Ok(())
+}

compliance/compliance-server/src/error.rs

@@ -9,14 +9,23 @@ use warp::reject::Reject;
 pub enum ComplianceServerError {
     /// An error with a database query
     Db(String),
+    /// An error with the chainalysis API
+    Chainalysis(String),
 }
 
 impl Display for ComplianceServerError {
     fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
         match self {
             ComplianceServerError::Db(e) => write!(f, "Database error: {}", e),
+            ComplianceServerError::Chainalysis(e) => write!(f, "Chainalysis error: {}", e),
         }
     }
 }
 impl Error for ComplianceServerError {}
 impl Reject for ComplianceServerError {}
+
+impl From<reqwest::Error> for ComplianceServerError {
+    fn from(e: reqwest::Error) -> Self {
+        ComplianceServerError::Chainalysis(e.to_string())
+    }
+}

compliance/compliance-server/src/main.rs

@@ -5,20 +5,25 @@
 #![deny(unsafe_code)]
 #![deny(clippy::needless_pass_by_value)]
 #![deny(clippy::needless_pass_by_ref_mut)]
+#![feature(duration_constructors)]
 
 use std::sync::Arc;
 
+use chainalysis_api::query_chainalysis;
 use clap::Parser;
 use compliance_api::{ComplianceCheckResponse, ComplianceStatus};
+use db::insert_compliance_entry;
 use diesel::pg::PgConnection;
 use diesel::r2d2::{ConnectionManager, Pool};
 use error::ComplianceServerError;
 use renegade_util::err_str;
 use renegade_util::telemetry::{setup_system_logger, LevelFilter};
+use tracing::info;
 use warp::{reply::Json, Filter};
 
 use crate::db::get_compliance_entry;
 
+pub mod chainalysis_api;
 pub mod db;
 pub mod error;
 #[allow(missing_docs, clippy::missing_docs_in_private_items)]
@@ -56,7 +61,7 @@ async fn main() {
     let chainalysis_key = cli.chainalysis_api_key.clone();
     let compliance_check = warp::get()
         .and(warp::path("v0"))
-        .and(warp::path("compliance-check"))
+        .and(warp::path("check-compliance"))
         .and(warp::path::param::<String>()) // wallet_address
         .and_then(move |wallet_address| {
             let key = chainalysis_key.clone();
@@ -102,5 +107,10 @@ async fn check_wallet_compliance(
     }
 
     // 2. If not present, check the chainalysis API
-    Ok(ComplianceStatus::Compliant)
+    info!("address not cached in DB, querying Chainalysis");
+    let compliance_entry = query_chainalysis(&wallet_address, chainalysis_api_key).await?;
+
+    // 3. Cache in the DB
+    insert_compliance_entry(compliance_entry.clone(), &mut conn)?;
+    Ok(compliance_entry.compliance_status())
 }

compliance/compliance-server/src/schema.rs

@@ -4,6 +4,7 @@ diesel::table! {
     wallet_compliance (address) {
         address -> Text,
         is_compliant -> Bool,
+        risk_level -> Text,
         reason -> Text,
         created_at -> Timestamp,
         expires_at -> Timestamp,