Restart shovels on failure

scraper_service/requirements.txt

@@ -27,7 +27,6 @@ requests==2.32.3
 scalecodec==1.2.10
 six==1.16.0
 substrate-interface==1.7.10
-tenacity==9.0.0
 toolz==0.12.1
 tqdm==4.66.4
 typing_extensions==4.12.2

scraper_service/shared/exceptions.py

@@ -0,0 +1,11 @@
+class ShovelException(Exception):
+    """Base exception for all shovel-related errors"""
+    pass
+
+class ShovelProcessingError(ShovelException):
+    """Fatal error that should crash the process"""
+    pass
+
+class DatabaseConnectionError(ShovelException):
+    """Retryable error for database connection issues"""
+    pass

scraper_service/shared/shovel_base_class.py

@@ -1,21 +1,25 @@
 from shared.clickhouse.batch_insert import buffer_insert, flush_buffer, batch_insert_into_clickhouse_table
-from shared.substrate import get_substrate_client
+from shared.substrate import get_substrate_client, reconnect_substrate
 from time import sleep
 from shared.clickhouse.utils import (
     get_clickhouse_client,
     table_exists,
 )
+from shared.exceptions import DatabaseConnectionError, ShovelProcessingError
 from tqdm import tqdm
 import logging
 import threading
 from concurrent.futures import ThreadPoolExecutor
+import sys
 
 
 class ShovelBaseClass:
     checkpoint_block_number = 0
     last_buffer_flush_call_block_number = 0
     name = None
     skip_interval = 1
+    MAX_RETRIES = 3
+    RETRY_DELAY = 5
 
     def __init__(self, name, skip_interval=1):
         """
@@ -26,49 +30,80 @@ def __init__(self, name, skip_interval=1):
         self.starting_block = 0  # Default value, can be overridden by subclasses
 
     def start(self):
-        print("Initialising Substrate client")
-        substrate = get_substrate_client()
-
-        print("Fetching the finalized block")
-        finalized_block_hash = substrate.get_chain_finalised_head()
-        finalized_block_number = substrate.get_block_number(
-            finalized_block_hash)
-
-        # Start the clickhouse buffer
-        print("Starting Clickhouse buffer")
-        executor = ThreadPoolExecutor(max_workers=1)
-        threading.Thread(
-            target=flush_buffer,
-            args=(executor, self._buffer_flush_started, self._buffer_flush_done),
-        ).start()
-
-        last_scraped_block_number = self.get_checkpoint()
-        logging.info(f"Last scraped block is {last_scraped_block_number}")
-
-        # Create a list of block numbers to scrape
+        retry_count = 0
         while True:
-            block_numbers = tqdm(
-                range(last_scraped_block_number +
-                      1, finalized_block_number + 1, self.skip_interval)
-            )
-
-            if len(block_numbers) > 0:
-                logging.info(
-                    f"Catching up {len(block_numbers)} blocks")
-                for block_number in block_numbers:
-                    self.process_block(block_number)
-                    self.checkpoint_block_number = block_number
-            else:
-                logging.info(
-                    "Already up to latest finalized block, checking again in 12s...")
-
-            # Make sure to sleep so buffer with checkpoint update is flushed to Clickhouse
-            # before trying again
-            sleep(12)
-            last_scraped_block_number = self.get_checkpoint()
-            finalized_block_hash = substrate.get_chain_finalised_head()
-            finalized_block_number = substrate.get_block_number(
-                finalized_block_hash)
+            try:
+                print("Initialising Substrate client")
+                substrate = get_substrate_client()
+
+                print("Fetching the finalized block")
+                finalized_block_hash = substrate.get_chain_finalised_head()
+                finalized_block_number = substrate.get_block_number(finalized_block_hash)
+
+                # Start the clickhouse buffer
+                print("Starting Clickhouse buffer")
+                executor = ThreadPoolExecutor(max_workers=1)
+                buffer_thread = threading.Thread(
+                    target=flush_buffer,
+                    args=(executor, self._buffer_flush_started, self._buffer_flush_done),
+                    daemon=True  # Make it a daemon thread so it exits with the main thread
+                )
+                buffer_thread.start()
+
+                last_scraped_block_number = self.get_checkpoint()
+                logging.info(f"Last scraped block is {last_scraped_block_number}")
+
+                # Create a list of block numbers to scrape
+                while True:
+                    try:
+                        block_numbers = list(range(
+                            last_scraped_block_number + 1,
+                            finalized_block_number + 1,
+                            self.skip_interval
+                        ))
+
+                        if len(block_numbers) > 0:
+                            logging.info(f"Catching up {len(block_numbers)} blocks")
+                            for block_number in tqdm(block_numbers):
+                                try:
+                                    self.process_block(block_number)
+                                    self.checkpoint_block_number = block_number
+                                except DatabaseConnectionError as e:
+                                    logging.error(f"Database connection error while processing block {block_number}: {str(e)}")
+                                    raise  # Re-raise to be caught by outer try-except
+                                except Exception as e:
+                                    logging.error(f"Fatal error while processing block {block_number}: {str(e)}")
+                                    raise ShovelProcessingError(f"Failed to process block {block_number}: {str(e)}")
+                        else:
+                            logging.info("Already up to latest finalized block, checking again in 12s...")
+
+                        # Reset retry count on successful iteration
+                        retry_count = 0
+
+                        # Make sure to sleep so buffer with checkpoint update is flushed to Clickhouse
+                        sleep(12)
+                        last_scraped_block_number = self.get_checkpoint()
+                        finalized_block_hash = substrate.get_chain_finalised_head()
+                        finalized_block_number = substrate.get_block_number(finalized_block_hash)
+
+                    except DatabaseConnectionError as e:
+                        retry_count += 1
+                        if retry_count > self.MAX_RETRIES:
+                            logging.error(f"Max retries ({self.MAX_RETRIES}) exceeded for database connection. Exiting.")
+                            raise ShovelProcessingError("Max database connection retries exceeded")
+
+                        logging.warning(f"Database connection error (attempt {retry_count}/{self.MAX_RETRIES}): {str(e)}")
+                        logging.info(f"Retrying in {self.RETRY_DELAY} seconds...")
+                        sleep(self.RETRY_DELAY)
+                        reconnect_substrate()  # Try to reconnect to substrate
+                        continue
+
+            except ShovelProcessingError as e:
+                logging.error(f"Fatal shovel error: {str(e)}")
+                sys.exit(1)
+            except Exception as e:
+                logging.error(f"Unexpected error: {str(e)}")
+                sys.exit(1)
 
     def process_block(self, n):
         raise NotImplementedError(
@@ -106,7 +141,18 @@ def _buffer_flush_done(self, tables, rows):
 
     def get_checkpoint(self):
         if not table_exists("shovel_checkpoints"):
-            return self.starting_block - 1
+            return max(0, self.starting_block - 1)
+
+        # First check if our shovel has any entries
+        query = f"""
+            SELECT count(*)
+            FROM shovel_checkpoints
+            WHERE shovel_name = '{self.name}'
+        """
+        count = get_clickhouse_client().execute(query)[0][0]
+        if count == 0:
+            return max(0, self.starting_block - 1)
+
         query = f"""
             SELECT block_number
             FROM shovel_checkpoints
@@ -118,4 +164,4 @@ def get_checkpoint(self):
         if res:
             return res[0][0]
         else:
-            return self.starting_block - 1
+            return max(0, self.starting_block - 1)  # This case shouldn't happen due to count check above

scraper_service/shovel_block_timestamp/main.py

@@ -5,6 +5,7 @@
     get_clickhouse_client,
     table_exists,
 )
+from shared.exceptions import DatabaseConnectionError, ShovelProcessingError
 import logging
 
 
@@ -20,31 +21,50 @@ def process_block(self, n):
 
 
 def do_process_block(self, n):
-    substrate = get_substrate_client()
-
-    # Create table if it doesn't exist
-    if not table_exists(self.table_name):
-        query = f"""
-        CREATE TABLE IF NOT EXISTS {self.table_name} (
-            block_number UInt64 CODEC(Delta, ZSTD),
-            timestamp DateTime CODEC(Delta, ZSTD),
-        ) ENGINE = ReplacingMergeTree()
-        PARTITION BY toYYYYMM(timestamp)
-        ORDER BY block_number
-        """
-        get_clickhouse_client().execute(query)
-
-    block_hash = substrate.get_block_hash(n)
-    block_timestamp = int(
-        substrate.query(
-            "Timestamp",
-            "Now",
-            block_hash=block_hash,
-        ).serialize()
-        / 1000
-    )
-
-    buffer_insert(self.table_name, [n, block_timestamp])
+    try:
+        substrate = get_substrate_client()
+
+        try:
+            if not table_exists(self.table_name):
+                query = f"""
+                CREATE TABLE IF NOT EXISTS {self.table_name} (
+                    block_number UInt64 CODEC(Delta, ZSTD),
+                    timestamp DateTime CODEC(Delta, ZSTD),
+                ) ENGINE = ReplacingMergeTree()
+                PARTITION BY toYYYYMM(timestamp)
+                ORDER BY block_number
+                """
+                get_clickhouse_client().execute(query)
+        except Exception as e:
+            raise DatabaseConnectionError(f"Failed to create/check table: {str(e)}")
+
+        try:
+            block_hash = substrate.get_block_hash(n)
+            block_timestamp = int(
+                substrate.query(
+                    "Timestamp",
+                    "Now",
+                    block_hash=block_hash,
+                ).serialize()
+                / 1000
+            )
+        except Exception as e:
+            raise ShovelProcessingError(f"Failed to get block timestamp from substrate: {str(e)}")
+
+        if block_timestamp == 0 and n != 0:
+            raise ShovelProcessingError(f"Invalid block timestamp (0) for block {n}")
+
+        try:
+            buffer_insert(self.table_name, [n, block_timestamp])
+        except Exception as e:
+            raise DatabaseConnectionError(f"Failed to insert data into buffer: {str(e)}")
+
+    except (DatabaseConnectionError, ShovelProcessingError):
+        # Re-raise these exceptions to be handled by the base class
+        raise
+    except Exception as e:
+        # Convert unexpected exceptions to ShovelProcessingError
+        raise ShovelProcessingError(f"Unexpected error processing block {n}: {str(e)}")
 
 
 def main():