config: Add a timeout option for the ethereum client

Author: aliel

src/aleph/chains/ethereum.py

@@ -36,7 +36,7 @@
 
 
 def get_web3(config) -> Web3:
-    web3 = Web3(Web3.HTTPProvider(config.ethereum.api_url.value))
+    web3 = Web3(Web3.HTTPProvider(config.ethereum.api_url.value, request_kwargs={'timeout': config.ethereum.client_timeout}))
     if config.ethereum.chain_id.value == 4:  # rinkeby
         web3.middleware_onion.inject(geth_poa_middleware, layer=0)
     web3.middleware_onion.add(local_filter_middleware)

src/aleph/config.py

@@ -122,6 +122,8 @@ def get_defaults():
             "max_gas_price": 150000000000,
             # Authorized publishers for sync events.
             "authorized_emitters": ["0x23eC28598DCeB2f7082Cc3a9D670592DfEd6e0dC"],
+            # http client timeout, default 60s
+            "client_timeout": 60
         },
         "tezos": {
             # Whether to fetch transactions from Tezos.