Make miner optional

Signed-off-by: Julien Riou <julien@riou.xyz>

README.md

@@ -2,7 +2,7 @@
 
 [Flexpool.io](https://flexpool.io) is a next-generation [Ethereum](https://ethereum.org/en/) mining pool known for their
 [#STOPEIP1559](https://stopeip1559.org/) move. `flexpool-activity` is able to listen and notify when a new **block** is
-mined by the pool and display the up-to-date **miner balance** and convert it to **fiat**.
+mined by the pool, display the up-to-date **miner balance** and convert it to **fiat**.
 
 ## Installation
 
@@ -21,7 +21,7 @@ bot. You'll need the `chat_id` and `auth_key` for the next section.
 ## Configuration
 
 Configuration file use the JSON format with the following keys:
-* `miner`: wallet address of the miner
+* `miner`: wallet address of the miner (optional)
 * `currency`: symbol of the currency to convert (optional)
 * `telegram`: send notifications with Telegram (optional)
     * `auth_key`: Telegram authentication key for the bot API

config.schema.json

@@ -22,8 +22,5 @@
     "state_file": {
       "type": "string"
     }
-  },
-  "required": [
-    "miner"
-  ]
+  }
 }

main.py

@@ -118,11 +118,12 @@ def main():
     logger.debug('saving block number to state file')
     write_state(state_file, block_number=block.number)
 
-    miner = watch_miner(last_balance=state.get('balance'), address=config['miner'], config=config,
-                        disable_notifications=args.disable_notifications, exchange_rate=exchange_rate,
-                        currency=currency)
-    logger.debug('saving miner balance to state file')
-    write_state(state_file, miner_balance=miner.raw_balance)
+    if config.get('miner'):
+        miner = watch_miner(last_balance=state.get('balance'), address=config['miner'], config=config,
+                            disable_notifications=args.disable_notifications, exchange_rate=exchange_rate,
+                            currency=currency)
+        logger.debug('saving miner balance to state file')
+        write_state(state_file, miner_balance=miner.raw_balance)
 
 
 if __name__ == '__main__':