Write logs to file, split by database (#9)

mysql_ch_replicator/db_replicator.py

@@ -82,6 +82,7 @@ class Statistics:
     insert_records_count: int = 0
     erase_events_count: int = 0
     erase_records_count: int = 0
+    no_events_count: int = 0
 
 
 class DbReplicator:
@@ -124,6 +125,7 @@ def __init__(self, config: Settings, database: str, target_database: str = None,
         self.last_touch_time = 0
 
     def run(self):
+        logger.info('launched db_replicator')
         if self.state.status == Status.RUNNING_REALTIME_REPLICATION:
             self.run_realtime_replication()
             return
@@ -226,6 +228,9 @@ def perform_initial_replication_table(self, table_name):
         primary_key_index = field_names.index(primary_key)
         primary_key_type = field_types[primary_key_index]
 
+        stats_number_of_records = 0
+        last_stats_dump_time = time.time()
+
         while True:
 
             query_start_value = max_primary_key
@@ -258,6 +263,14 @@ def perform_initial_replication_table(self, table_name):
             self.save_state_if_required()
             self.prevent_binlog_removal()
 
+            stats_number_of_records += len(records)
+            curr_time = time.time()
+            if curr_time - last_stats_dump_time >= 60.0:
+                last_stats_dump_time = curr_time
+                logger.info(
+                    f'replicating {table_name}, replicated {stats_number_of_records}, primary key: {max_primary_key}',
+                )
+
     def run_realtime_replication(self):
         if self.initial_only:
             logger.info('skip running realtime replication, only initial replication was requested')
@@ -277,6 +290,8 @@ def run_realtime_replication(self):
             if event is None:
                 time.sleep(DbReplicator.READ_LOG_INTERVAL)
                 self.upload_records_if_required(table_name=None)
+                self.stats.no_events_count += 1
+                self.log_stats_if_required()
                 continue
             assert event.db_name == self.database
             if self.database != self.target_database:
@@ -402,7 +417,7 @@ def log_stats_if_required(self):
         if curr_time - self.last_dump_stats_time < DbReplicator.STATS_DUMP_INTERVAL:
             return
         self.last_dump_stats_time = curr_time
-        logger.info(f'statistics:\n{json.dumps(self.stats.__dict__, indent=3)}')
+        logger.info(f'statistics:\n{json.dumps(self.stats.__dict__)}')
         self.stats = Statistics()
 
     def upload_records_if_required(self, table_name):

mysql_ch_replicator/main.py

@@ -2,6 +2,9 @@
 
 import argparse
 import logging
+from logging.handlers import RotatingFileHandler
+import sys
+import os
 
 from .config import Settings
 from .db_replicator import DbReplicator
@@ -10,15 +13,38 @@
 from .runner import Runner
 
 
-def set_logging_config(tags):
+def set_logging_config(tags, log_file=None):
+
+    handlers = []
+    handlers.append(logging.StreamHandler(sys.stderr))
+    if log_file is not None:
+        handlers.append(
+            RotatingFileHandler(
+                filename=log_file,
+                maxBytes=50*1024*1024,  # 50 Mb
+                backupCount=3,
+                encoding='utf-8',
+                delay=False,
+            )
+        )
+
     logging.basicConfig(
         level=logging.INFO,
         format=f'[{tags} %(asctime)s %(levelname)8s] %(message)s',
+        handlers=handlers,
     )
 
 
 def run_binlog_replicator(args, config: Settings):
-    set_logging_config('binlogrepl')
+    if not os.path.exists(config.binlog_replicator.data_dir):
+        os.mkdir(config.binlog_replicator.data_dir)
+
+    log_file = os.path.join(
+        config.binlog_replicator.data_dir,
+        'binlog_replicator.log',
+    )
+
+    set_logging_config('binlogrepl', log_file=log_file)
     binlog_replicator = BinlogReplicator(
         settings=config,
     )
@@ -29,11 +55,29 @@ def run_db_replicator(args, config: Settings):
     if not args.db:
         raise Exception("need to pass --db argument")
 
-    set_logging_config(f'dbrepl {args.db}')
+    db_name = args.db
+
+    if not os.path.exists(config.binlog_replicator.data_dir):
+        os.mkdir(config.binlog_replicator.data_dir)
+
+    db_dir = os.path.join(
+        config.binlog_replicator.data_dir,
+        db_name,
+    )
+
+    if not os.path.exists(db_dir):
+        os.mkdir(db_dir)
+
+    log_file = os.path.join(
+        db_dir,
+        'db_replicator.log',
+    )
+
+    set_logging_config(f'dbrepl {args.db}', log_file=log_file)
 
     db_replicator = DbReplicator(
         config=config,
-        database=args.db,
+        database=db_name,
         target_database=getattr(args, 'target_db', None),
         initial_only=args.initial_only,
     )