Enable contract feature detection

Contracts updated to version 0.5.0.

contracts/IERC165.json

@@ -0,0 +1,30 @@
+{
+  "_format": "hh-sol-artifact-1",
+  "contractName": "IERC165",
+  "sourceName": "@openzeppelin/contracts/utils/introspection/IERC165.sol",
+  "abi": [
+    {
+      "inputs": [
+        {
+          "internalType": "bytes4",
+          "name": "interfaceId",
+          "type": "bytes4"
+        }
+      ],
+      "name": "supportsInterface",
+      "outputs": [
+        {
+          "internalType": "bool",
+          "name": "",
+          "type": "bool"
+        }
+      ],
+      "stateMutability": "view",
+      "type": "function"
+    }
+  ],
+  "bytecode": "0x",
+  "deployedBytecode": "0x",
+  "linkReferences": {},
+  "deployedLinkReferences": {}
+}

contracts/IGate.json

@@ -0,0 +1,30 @@
+{
+  "_format": "hh-sol-artifact-1",
+  "contractName": "IGate",
+  "sourceName": "contracts/interfaces/IGate.sol",
+  "abi": [
+    {
+      "inputs": [
+        {
+          "internalType": "address",
+          "name": "user",
+          "type": "address"
+        }
+      ],
+      "name": "isAllowedUser",
+      "outputs": [
+        {
+          "internalType": "bool",
+          "name": "",
+          "type": "bool"
+        }
+      ],
+      "stateMutability": "view",
+      "type": "function"
+    }
+  ],
+  "bytecode": "0x",
+  "deployedBytecode": "0x",
+  "linkReferences": {},
+  "deployedLinkReferences": {}
+}

contracts/IMinter.json

@@ -0,0 +1,57 @@
+{
+  "_format": "hh-sol-artifact-1",
+  "contractName": "IMinter",
+  "sourceName": "contracts/interfaces/IMinter.sol",
+  "abi": [
+    {
+      "inputs": [],
+      "name": "collectible",
+      "outputs": [
+        {
+          "internalType": "contract IERC721Metadata",
+          "name": "",
+          "type": "address"
+        }
+      ],
+      "stateMutability": "view",
+      "type": "function"
+    },
+    {
+      "inputs": [
+        {
+          "internalType": "address",
+          "name": "user",
+          "type": "address"
+        },
+        {
+          "internalType": "string",
+          "name": "tokenURI",
+          "type": "string"
+        },
+        {
+          "internalType": "uint8",
+          "name": "v",
+          "type": "uint8"
+        },
+        {
+          "internalType": "bytes32",
+          "name": "r",
+          "type": "bytes32"
+        },
+        {
+          "internalType": "bytes32",
+          "name": "s",
+          "type": "bytes32"
+        }
+      ],
+      "name": "mint",
+      "outputs": [],
+      "stateMutability": "nonpayable",
+      "type": "function"
+    }
+  ],
+  "bytecode": "0x",
+  "deployedBytecode": "0x",
+  "linkReferences": {},
+  "deployedLinkReferences": {}
+}

contracts/ISubscription.json

@@ -71,6 +71,13 @@
       "outputs": [],
       "stateMutability": "nonpayable",
       "type": "function"
+    },
+    {
+      "inputs": [],
+      "name": "withdrawReceivedAll",
+      "outputs": [],
+      "stateMutability": "nonpayable",
+      "type": "function"
     }
   ],
   "bytecode": "0x",

contracts/ISubscriptionAdapter.json

@@ -1,21 +1,8 @@
 {
   "_format": "hh-sol-artifact-1",
-  "contractName": "IAdapter",
+  "contractName": "ISubscriptionAdapter",
-  "sourceName": "contracts/interfaces/IAdapter.sol",
+  "sourceName": "contracts/interfaces/ISubscriptionAdapter.sol",
   "abi": [
-    {
-      "inputs": [],
-      "name": "collectible",
-      "outputs": [
-        {
-          "internalType": "contract IERC721Metadata",
-          "name": "",
-          "type": "address"
-        }
-      ],
-      "stateMutability": "view",
-      "type": "function"
-    },
     {
       "inputs": [
         {
@@ -97,25 +84,6 @@
       "stateMutability": "view",
       "type": "function"
     },
-    {
-      "inputs": [
-        {
-          "internalType": "address",
-          "name": "user",
-          "type": "address"
-        }
-      ],
-      "name": "isAllowedUser",
-      "outputs": [
-        {
-          "internalType": "bool",
-          "name": "",
-          "type": "bool"
-        }
-      ],
-      "stateMutability": "view",
-      "type": "function"
-    },
     {
       "inputs": [
         {
@@ -135,39 +103,6 @@
       "stateMutability": "view",
       "type": "function"
     },
-    {
-      "inputs": [
-        {
-          "internalType": "address",
-          "name": "user",
-          "type": "address"
-        },
-        {
-          "internalType": "string",
-          "name": "tokenURI",
-          "type": "string"
-        },
-        {
-          "internalType": "uint8",
-          "name": "v",
-          "type": "uint8"
-        },
-        {
-          "internalType": "bytes32",
-          "name": "r",
-          "type": "bytes32"
-        },
-        {
-          "internalType": "bytes32",
-          "name": "s",
-          "type": "bytes32"
-        }
-      ],
-      "name": "mint",
-      "outputs": [],
-      "stateMutability": "nonpayable",
-      "type": "function"
-    },
     {
       "inputs": [],
       "name": "subscription",

docs/openapi.yaml

@@ -782,6 +782,19 @@ components:
           description: Blockchain contract address.
           type: string
           nullable: true
+        blockchain_features:
+          description: Blockchain contract features.
+          type: object
+          nullable: true
+          properties:
+            minter:
+              description: Minter feature flag.
+              type: boolean
+              example: true
+            subscription:
+              description: Subscription feature flag.
+              type: boolean
+              example: true
         blockchain_info:
           description: Additional information about blockchain
           type: object

src/ethereum/contracts.rs

@@ -3,7 +3,7 @@ use std::path::Path;
 
 use web3::{
     api::Web3,
-    contract::{Contract, Options},
+    contract::{Contract, Error as ContractError, Options},
     ethabi,
     transports::Http,
 };
@@ -17,7 +17,10 @@ use super::sync::{
 };
 use super::utils::parse_address;
 
-const ADAPTER: &str = "IAdapter";
+const ERC165: &str = "IERC165";
+const GATE: &str = "IGate";
+const MINTER: &str = "IMinter";
+const SUBSCRIPTION_ADAPTER: &str = "ISubscriptionAdapter";
 const SUBSCRIPTION: &str = "ISubscription";
 const ERC721: &str = "IERC721Metadata";
 
@@ -51,13 +54,38 @@ fn load_abi(
     Ok(abi)
 }
 
+// https://eips.ethereum.org/EIPS/eip-165
+// Interface identifier is the XOR of all function selectors in the interface
+fn interface_signature(interface: &ethabi::Contract) -> [u8; 4] {
+    interface.functions()
+        .map(|func| func.short_signature())
+        .fold([0; 4], |mut acc, item| {
+            for i in 0..4 {
+                acc[i] ^= item[i];
+            };
+            acc
+        })
+}
+
+/// Returns true if contract supports interface (per ERC-165)
+async fn is_interface_supported(
+    contract: &Contract<Http>,
+    interface: &ethabi::Contract,
+) -> Result<bool, ContractError> {
+    let signature = interface_signature(interface);
+    contract.query(
+        "supportsInterface",
+        (signature,), None, Options::default(), None,
+    ).await
+}
+
 #[derive(Clone)]
 pub struct ContractSet {
     pub web3: Web3<Http>,
 
-    pub adapter: Contract<Http>,
+    pub gate: Option<Contract<Http>>,
-    pub collectible: Contract<Http>,
+    pub collectible: Option<Contract<Http>>,
-    pub subscription: Contract<Http>,
+    pub subscription: Option<Contract<Http>>,
 }
 
 #[derive(Clone)]
@@ -75,15 +103,40 @@ pub async fn get_contracts(
     if chain_id != config.ethereum_chain_id().into() {
         return Err(EthereumError::ImproperlyConfigured("incorrect chain ID"));
     };
-    let adapter_abi = load_abi(&config.contract_dir, ADAPTER)?;
+
     let adapter_address = parse_address(&config.contract_address)?;
-    let adapter = Contract::new(
+    let erc165_abi = load_abi(&config.contract_dir, ERC165)?;
+    let erc165 = Contract::new(
         web3.eth(),
         adapter_address,
-        adapter_abi,
+        erc165_abi,
     );
 
-    let collectible_address = adapter.query(
+    let mut maybe_gate = None;
+    let mut maybe_collectible = None;
+    let mut maybe_subscription = None;
+    let mut sync_targets = vec![];
+
+    let gate_abi = load_abi(&config.contract_dir, GATE)?;
+    if is_interface_supported(&erc165, &gate_abi).await? {
+        let gate = Contract::new(
+            web3.eth(),
+            adapter_address,
+            gate_abi,
+        );
+        maybe_gate = Some(gate);
+        log::info!("found gate interface");
+    };
+
+    let minter_abi = load_abi(&config.contract_dir, MINTER)?;
+    if is_interface_supported(&erc165, &minter_abi).await? {
+        let minter = Contract::new(
+            web3.eth(),
+            adapter_address,
+            minter_abi,
+        );
+        log::info!("found minter interface");
+        let collectible_address = minter.query(
             "collectible",
             (), None, Options::default(), None,
         ).await?;
@@ -94,8 +147,19 @@ pub async fn get_contracts(
             collectible_abi,
         );
         log::info!("collectible item contract address is {:?}", collectible.address());
+        sync_targets.push(collectible.address());
+        maybe_collectible = Some(collectible);
+    };
 
-    let subscription_address = adapter.query(
+    let subscription_adapter_abi = load_abi(&config.contract_dir, SUBSCRIPTION_ADAPTER)?;
+    if is_interface_supported(&erc165, &subscription_adapter_abi).await? {
+        let subscription_adapter = Contract::new(
+            web3.eth(),
+            adapter_address,
+            subscription_adapter_abi,
+        );
+        log::info!("found subscription interface");
+        let subscription_address = subscription_adapter.query(
             "subscription",
             (), None, Options::default(), None,
         ).await?;
@@ -106,20 +170,23 @@ pub async fn get_contracts(
             subscription_abi,
         );
         log::info!("subscription contract address is {:?}", subscription.address());
+        sync_targets.push(subscription.address());
+        maybe_subscription = Some(subscription);
+    };
 
     let current_block = get_current_block_number(&web3, storage_dir).await?;
     log::info!("current block is {}", current_block);
     let sync_state = SyncState::new(
         current_block,
-        vec![collectible.address(), subscription.address()],
+        sync_targets,
         storage_dir,
     );
 
     let contract_set = ContractSet {
         web3,
-        adapter,
+        gate: maybe_gate,
-        collectible,
+        collectible: maybe_collectible,
-        subscription,
+        subscription: maybe_subscription,
     };
     Ok(Blockchain { contract_set, sync_state })
 }

src/ethereum/gate.rs

@@ -8,8 +8,12 @@ pub async fn is_allowed_user(
     contract_set: &ContractSet,
     user_address: &str,
 ) -> Result<bool, EthereumError> {
+    let gate = match &contract_set.gate {
+        Some(contract) => contract,
+        None => return Ok(true), // no gate
+    };
     let user_address = parse_address(user_address)?;
-    let result: bool = contract_set.adapter.query(
+    let result: bool = gate.query(
         "isAllowedUser", (user_address,),
         None, Options::default(), None,
     ).await?;

src/mastodon_api/instance/types.rs

@@ -3,8 +3,15 @@ use std::collections::HashMap;
 use serde::Serialize;
 
 use crate::config::Config;
+use crate::ethereum::contracts::ContractSet;
 use crate::mastodon_api::MASTODON_API_VERSION;
 
+#[derive(Serialize)]
+struct BlockchainFeatures {
+    minter: bool,
+    subscription: bool,
+}
+
 #[derive(Serialize)]
 pub struct InstanceInfo {
     uri: String,
@@ -19,6 +26,7 @@ pub struct InstanceInfo {
     blockchain_id: Option<String>,
     blockchain_explorer_url: Option<String>,
     blockchain_contract_address: Option<String>,
+    blockchain_features: Option<BlockchainFeatures>,
     blockchain_info: Option<HashMap<String, String>>,
     ipfs_gateway_url: Option<String>,
 }
@@ -31,8 +39,14 @@ fn get_full_api_version(version: &str) -> String {
     )
 }
 
-impl From<&Config> for InstanceInfo {
+impl InstanceInfo {
-    fn from(config: &Config) -> Self {
+    pub fn create(config: &Config, maybe_blockchain: Option<&ContractSet>) -> Self {
+        let blockchain_features = maybe_blockchain.map(|contract_set| {
+            BlockchainFeatures {
+                minter: contract_set.collectible.is_some(),
+                subscription: contract_set.subscription.is_some(),
+            }
+        });
         Self {
             uri: config.instance().host(),
             title: config.instance_title.clone(),
@@ -48,6 +62,7 @@ impl From<&Config> for InstanceInfo {
                 .and_then(|val| val.explorer_url.clone()),
             blockchain_contract_address: config.blockchain.as_ref()
                 .map(|val| val.contract_address.clone()),
+            blockchain_features: blockchain_features,
             blockchain_info: config.blockchain.as_ref()
                 .and_then(|val| val.chain_info.clone()),
             ipfs_gateway_url: config.ipfs_gateway_url.clone(),

src/mastodon_api/instance/views.rs

@@ -2,13 +2,18 @@ use actix_web::{get, web, HttpResponse, Scope};
 
 use crate::config::Config;
 use crate::errors::HttpError;
+use crate::ethereum::contracts::ContractSet;
 use super::types::InstanceInfo;
 
 #[get("")]
 async fn instance_view(
     config: web::Data<Config>,
+    maybe_blockchain: web::Data<Option<ContractSet>>,
 ) -> Result<HttpResponse, HttpError> {
-    let instance = InstanceInfo::from(config.as_ref());
+    let instance = InstanceInfo::create(
+        config.as_ref(),
+        maybe_blockchain.as_ref().as_ref(),
+    );
     Ok(HttpResponse::Ok().json(instance))
 }
 

src/scheduler.rs

@@ -46,9 +46,13 @@ async fn nft_monitor_task(
         Some(blockchain) => blockchain,
         None => return Ok(()),
     };
+    let collectible = match &blockchain.contract_set.collectible {
+        Some(contract) => contract,
+        None => return Ok(()), // feature not enabled
+    };
     process_nft_events(
         &blockchain.contract_set.web3,
-        &blockchain.contract_set.collectible,
+        &collectible,
         &mut blockchain.sync_state,
         db_pool,
         token_waitlist_map,
@@ -64,9 +68,13 @@ async fn subscription_monitor_task(
         Some(blockchain) => blockchain,
         None => return Ok(()),
     };
+    let subscription = match &blockchain.contract_set.subscription {
+        Some(contract) => contract,
+        None => return Ok(()), // feature not enabled
+    };
     check_subscriptions(
         &blockchain.contract_set.web3,
-        &blockchain.contract_set.subscription,
+        &subscription,
         &mut blockchain.sync_state,
         db_pool,
     ).await.map_err(Error::from)