Add handler to send log messages to specific Redis list

Class `RedisMessageListHandler` builds a log handler that pushes any
messages logged out to the redis list specified by its
`fullyqualifiedkey` argument.

1 files changed, 21 insertions, 0 deletions

diff --git a/scripts/redis_logger.py b/scripts/redis_logger.py
index 2ae682b..d3fde5f 100644
--- a/scripts/redis_logger.py
+++ b/scripts/redis_logger.py
@@ -1,5 +1,6 @@
 """Utilities to log to redis for our worker scripts."""
 import logging
+from typing import Optional
 
 from redis import Redis
 
@@ -26,6 +27,26 @@ class RedisLogger(logging.Handler):
         self.redisconnection.rpush(self.messageslistname, self.format(record))
         self.redisconnection.expire(self.messageslistname, self.expiry)
 
+class RedisMessageListHandler(logging.Handler):
+    """Send messages to specified redis list."""
+    def __init__(self,
+                 rconn: Redis,
+                 fullyqualifiedkey: str,
+                 loglevel: int = logging.NOTSET,
+                 expiry: Optional[int] = 86400):
+        super().__init__(loglevel)
+        self.redisconnection = rconn
+        self.fullyqualifiedkey = fullyqualifiedkey
+        self.expiry = expiry
+
+    def emit(self, record):
+        """Log out to specified `fullyqualifiedkey`."""
+        self.redisconnection.rpush(self.fullyqualifiedkey, self.format(record))
+        if bool(self.expiry):
+            self.redisconnection.expire(self.fullyqualifiedkey, self.expiry)
+        else:
+            self.redisconnection.persist(self.fullyqualifiedkey)
+
 def setup_redis_logger(rconn: Redis,
                        fullyqualifiedjobid: str,
                        job_messagelist: str,