Allow multiple configurations in blockchains array

CHANGELOG.md

@@ -11,6 +11,7 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/).
 - Added emoji count check to profile data validator.
 - Check mention and link counts when creating post.
 - Disable transaction monitor tasks if blockchain integration is disabled.
+- Allow multiple configurations in `blockchains` array.
 
 ## [1.20.0] - 2023-03-07
 

contrib/mitra_config.yaml

@@ -57,7 +57,7 @@ retention:
 #blocked_instances: []
 
 # Blockchain integrations
-# Multiple configuration are currently not allowed.
+# Multi-chain setups are currently not supported.
 # Chain metadata for EVM chains can be found at https://github.com/ethereum-lists/chains
 # Signing key for ethereum integration can be generated with `mitractl generate-ethereum-address`
 #blockchains:

mitra-config/src/config.rs

@@ -1,3 +1,4 @@
+use std::collections::HashMap;
 use std::path::PathBuf;
 
 use log::{Level as LogLevel};
@@ -125,8 +126,21 @@ impl Config {
         if let Some(ref _blockchain_config) = self._blockchain {
             panic!("'blockchain' setting is not supported anymore, use 'blockchains' instead");
         } else {
-            if self.blockchains.len() > 1 {
-                panic!("multichain deployments are not supported");
+            let is_error = self.blockchains.iter()
+                .fold(HashMap::new(), |mut map, blockchain_config| {
+                    let key = match blockchain_config {
+                        BlockchainConfig::Ethereum(_) => 1,
+                        BlockchainConfig::Monero(_) => 2,
+                    };
+                    map.entry(key)
+                        .and_modify(|count| *count += 1)
+                        .or_insert(1);
+                    map
+                })
+                .into_values()
+                .any(|count| count > 1);
+            if is_error {
+                panic!("'blockchains' array contains more than one chain of the same kind");
             };
             &self.blockchains
         }

mitra-config/src/loader.rs

@@ -102,6 +102,9 @@ pub fn parse_config() -> (Config, Vec<&'static str>) {
     };
     check_directory_owner(&config.storage_dir);
     config.try_instance_url().expect("invalid instance URI");
+    if config.blockchains().len() > 1 {
+        warnings.push("multichain deployments are not recommended");
+    };
     if let Some(ethereum_config) = config.ethereum_config() {
         ethereum_config.try_ethereum_chain_id().unwrap();
         if !ethereum_config.contract_dir.exists() {