Call manager contract to verify that user is allowed to sign up

README.md

@@ -5,6 +5,7 @@ Federated social network with smart contracts.
 - Built on [ActivityPub](https://activitypub.rocks/) protocol.
 - Lightweight.
 - Sign-in with Ethereum.
+- Proving membership with a token.
 - Converting posts into NFTs.
 - More crypto features in the future.
 

src/ethereum/gate.rs

@@ -0,0 +1,31 @@
+use web3::contract::{Contract, Options};
+
+use crate::config::Config;
+use super::api::connect;
+use super::nft::{MANAGER, load_abi, EthereumError};
+use super::utils::parse_address;
+
+pub async fn is_allowed_user(
+    config: &Config,
+    user_address: &str,
+) -> Result<bool, EthereumError> {
+    let json_rpc_url = config.ethereum_json_rpc_url.as_ref()
+        .ok_or(EthereumError::ImproperlyConfigured)?;
+    let web3 = connect(json_rpc_url)?;
+    let ethereum_config = config.ethereum_contract.as_ref()
+        .ok_or(EthereumError::ImproperlyConfigured)?;
+
+    let manager_abi = load_abi(&config.contract_dir, MANAGER)?;
+    let manager_address = parse_address(&ethereum_config.address)?;
+    let manager = Contract::from_json(
+        web3.eth(),
+        manager_address,
+        &manager_abi,
+    )?;
+    let user_address = parse_address(user_address)?;
+    let result: bool = manager.query(
+        "isAllowedUser", (user_address,),
+        None, Options::default(), None,
+    ).await?;
+    Ok(result)
+}

src/ethereum/mod.rs

@@ -1,3 +1,4 @@
 mod api;
+pub mod gate;
 pub mod nft;
 pub mod utils;

src/ethereum/nft.rs

@@ -71,7 +71,7 @@ pub enum EthereumError {
     SigError(#[from] SignatureError),
 }
 
-fn load_abi(
+pub fn load_abi(
     contract_dir: &PathBuf,
     contract_name: &str,
 ) -> Result<Vec<u8>, EthereumError> {

src/mastodon_api/users/views.rs

@@ -6,6 +6,7 @@ use actix_web::{
 use crate::config::Config;
 use crate::database::{Pool, get_database_client};
 use crate::errors::{HttpError, ValidationError};
+use crate::ethereum::gate::is_allowed_user;
 use crate::mastodon_api::accounts::types::{Account, AccountCreateData};
 use crate::models::users::queries::{
     is_valid_invite_code,
@@ -35,6 +36,13 @@ pub async fn create_user_view(
             Err(ValidationError("invalid invite code"))?;
         }
     }
+    if config.ethereum_contract.is_some() {
+        let is_allowed = is_allowed_user(&config, &user_data.wallet_address).await
+            .map_err(|_| HttpError::InternalError)?;
+        if !is_allowed {
+            Err(ValidationError("not allowed to sign up"))?;
+        }
+    }
     // Hash password and generate private key
     let password_hash = hash_password(&user_data.password)
         .map_err(|_| HttpError::InternalError)?;